https://www.switchcraft.org/home daily 0.75 2016-12-15 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1537559353125-B9BMNB11VVW5A8101ZB0/IMG_0168.jpg Home https://www.switchcraft.org/project-blog daily 0.75 2018-10-11 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489458865411-WR3TMXCNPVK4N1PMA78R/Current_sensor.png Project Blog https://www.switchcraft.org/project-blog/2018/9/9/update-on-the-inverter-card-now-with-front-end-included monthly 0.5 2018-09-09 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536503264537-FR0N8Z03ABYHJ4NVUNR5/InverterCard2.png Project Blog - Update on the inverter card (now with front-end included) - Inverter Only PCB with inverter only https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536503272966-WADUV3BK5FID4U3I81JS/TopView3D.png Project Blog - Update on the inverter card (now with front-end included) - Inverter + Rectifier PCB with added rectifier https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536509780605-06TFKZPJ273DDJYEG5ER/Screen+Shot+2018-09-09+at+18.12.17.png Project Blog - Update on the inverter card (now with front-end included) For those who are downloading the schematic from GitHub, all the non-trivial components has part number used by Element14 (also known as Newark and Farnell in different regions). This is referred to as "Farnell_ID" in the lists of fields in the component properties dialog. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536499654855-B4WP9IPSAM03F4YW815N/TopView3D.png Project Blog - Update on the inverter card (now with front-end included) Top view 3D-render. The rectangle to the left is the rectifier with a current sensor above and below. The two red office-building-like components are snubber capacitors. The black boxes on the bottom side are main DC-link capacitors while the square, white box with a copper roof at the right is the SiC transistor module with three current sensors sitting next to it. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536499899906-AMM9FMDDXDGLMY5NBTQK/BottomView3D.png Project Blog - Update on the inverter card (now with front-end included) The bottom side of the PCB contains most of the components used for the current- and voltage sensing. Also, of course, the DC-link capacitors. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536500780926-OSXCABJR6F5C89NZKOKV/TopView3D_Silkscreen.png Project Blog - Update on the inverter card (now with front-end included) Top view in 3D showing only the board with silkscreen (the white drawings and letters etc), the soldermask (the blue stuff) and the topside copper (the other stuff you can see shining trough the blue stuff, right?) Below are images shown without ray tracing for better clarity - also the bottom side is shown. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536515081538-AXG841D8KEFXCF4Z1EUV/TopSideSilk.png Project Blog - Update on the inverter card (now with front-end included) - Top Side https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536515080874-5F7B5M2312SGOSPN07K8/BottomSideSilk.png Project Blog - Update on the inverter card (now with front-end included) - Bottom Side https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536515143068-HF01P1E1O2AKHH8KUJ8G/PCB+Layout+All+Layers.png Project Blog - Update on the inverter card (now with front-end included) The PCB layout, showing all layers. Green are electrical connections (routes) located at the bottom side of the board while red are connections on the top side. The yellow circles all around are mounting holes with electrical connections to components with pins. One notable exception is the filled, yellow circle near the center of the board - this is a mounting hole for the transistor module. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536500201738-SN7YAQJN1THP7Q14POBT/PCB+Layout+Top+Layer.png Project Blog - Update on the inverter card (now with front-end included) This view highlights all the electrical connections on the top side. Here, the zones are very visible, the two largest ones are DC+ and DC- zones, while the three to the right are motor output zones to the motor terminal connector. The two small zones to the left are also DC+/-, but before the current sensor. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536515187757-MFEQCP0A686S9VTLJNQQ/image-asset.png Project Blog - Update on the inverter card (now with front-end included) This view highlight the connections on the bottom side. Mostly control circuitry, but the thick ones in the upper left corner belongs to the main AC supply into the rectifier. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536500341683-2KFLCQW55NY2AZXJCGC2/Schematic.png Project Blog - Update on the inverter card (now with front-end included) The circuit schematic for the whole board. Use to blue comments on the drawing to get an idea about what's what. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536510846364-EUIZMRDDT4GCFTJYJHLH/P1016436.jpg Project Blog - Update on the inverter card (now with front-end included) - Four existing cards Clockwise from back left: Inverter card, current sensing card, rectifier card and voltage sensing card https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536511166174-OGRRVN9JIHE2TF3RDAHD/P1016440.jpg Project Blog - Update on the inverter card (now with front-end included) - Something like this The new board drawn out at scale on my notebook, shown with the DC link capacitors, rectifier and transistor module. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1536511210854-GWOJDC2V7NAG9S32O9PB/P1016442.jpg Project Blog - Update on the inverter card (now with front-end included) - Strike a pose The main components https://www.switchcraft.org/project-blog/2018/9/2/inverter-card-rev-2 monthly 0.5 2018-09-02 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535883573615-7C4YVOV0JXKUW2FKWGGK/Schematic.png Project Blog - Inverter Card rev 2 The inverter card schematic: Power electronics on the top, transistor on the lower left, current sensors in the middle and 5V power supply in the lower right corner. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535882505866-UWF6WLL0KBIQHZ6XFI7S/RatsNet_PCB.png Project Blog - Inverter Card rev 2 Purple-framed components are on one side of the PCB while the green-framed components are on the reverse side. The white lines are where there should be electrical connections (routes). The component placement is not final. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535921224960-Q7J64P9724Q4A9RM2J6Y/Screen+Shot+2018-09-02+at+22.32.34.png Project Blog - Inverter Card rev 2 - PCB Layout Still early in design phase. Routes are sketches to see if this will work or not. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535921151542-JQEMZDZIBR386V8214RB/invertercard_bottom_beta.png Project Blog - Inverter Card rev 2 - PCB Bottom Components on the bottom side of the PCB. The DC-link capacitors are the large, black boxes. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535921152054-QDIK0I9KF3HA9I8DQB8A/invertercard_top_beta.png Project Blog - Inverter Card rev 2 - PCB Top view The top side of the PCB. 3 current sensors and the SiC transistor module is shown along with some other components https://www.switchcraft.org/project-blog/2017/9/1/designing-interface-pcbs-for-rectifier-and-inverter-modules monthly 0.5 2017-09-02 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504300562962-8JMAPPFSK8HZOTN5URGT/SEMIKRON_sk-95-dgl-126-24914310_picture.jpg Project Blog - Designing and producing interface PCBs for rectifier and inverter modules SEMIKRON SK 95 DGL 126 rectifier module in a SEMITOP 3 package https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504300618442-XQE5A770OI43P6OB3HRT/SEMIKRON_skiip-13acm12v18-25238280_picture.jpg Project Blog - Designing and producing interface PCBs for rectifier and inverter modules SEMIKRON SKiiP 13ACM12V18 three phase inverter module in a MiniSKiiP 1 package https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504302221012-ENRU20BJW6WCTDYRIXHB/SK_95_DGL_126_cad Project Blog - Designing and producing interface PCBs for rectifier and inverter modules CAD drawing of the SEMITOP3 diode rectifier module as per SEMIKRON datasheet https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504302296196-8ASOJ7D9OYCXMEEFU1NV/13ACM12V18_CAD Project Blog - Designing and producing interface PCBs for rectifier and inverter modules CAD drawing of the MiniSKiiP1 inverter module as per SEMIKRON datasheet https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504302632286-7IK3EJMKYA6CPZT6CDK9/SK_95_DGL_126_footprint Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The SEMITOP3 rectifier module's footprint as designed in KiCad footprint editor. Notice that the pins are mirrored horizontally as it is a through-hole component and thus should be connected at the reverse side of the PCB. The yellow circle in the center is for the mounting screw while the four solid yellow circles in the corner are for mounting pins. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504302661136-GCCUWR8YLIBB0UMANGL4/13ACM12V18_footprint Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The MiniSKiiP1 inverter module's footprint as designed in KiCad's footprint editor. This footprint is not mirrored as it is surface mounted with springs (red pads) instead of through-hole pins. The yellow circles are mounting hole (big) and for the alignement pin (small). https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504303346908-DOXGQRYFWHWFCEJ77IQT/SK_95_DGL_126_symbol Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Schematic symbol for the diode module. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504303370318-4YRGS5KH8N7NU485357Z/13ACM12V18_symbol Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Schematic symbol of the inverter module https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504305856387-J5HTP7MIDF4NNBSE5V8L/SK_95_DGL_126_3d_model Project Blog - Designing and producing interface PCBs for rectifier and inverter modules 3D model placement and scaling in FreeCAD using StepUp tools (right toolbox). The component 3D-file is having more pins than our actual rectifier module - hence the mismatch between pins and holes. This is because the package SEMITOP3 comes in various configurations for differently rated devices. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504305651667-NNHQVQHDKF2VSZXX6L41/13ASC12V18_3d_model Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Inverter module 3D-model: Nice and easy now; the component has been scaled and rotated, and now only needs to be lowered down on the footprint pads (notice that the springs are not visible as this component 3d model is only for the standardized MiniSKiiP package, but this is more than sufficient). https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504306050524-68961G5PIR4UH00X8F2E/rectifier_card_layout Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Trace and component layout of the rectifier module as designed in KiCad. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504308709329-C1DF0U2E9DG7ZHPF94ZH/rectifier_pcb_3d_model Project Blog - Designing and producing interface PCBs for rectifier and inverter modules When 3D-models are used, one gets a pretty good idea how the board would actually look when produced. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504308781893-K8YZJP7YWS5RIGLT95AH/rectifier_module_pcb_reverse Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Great success. The pins and holes are so perfectly matched that they could be considered watertight. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504309029793-G5C766QYNUEFIJWM7IHH/rectifier_pcb_front Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Rectifier module interface PCB - front side https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504308563881-UBLUME8IV5OZJ7KJCD6J/rectifier_module_pcb_as_manufactured Project Blog - Designing and producing interface PCBs for rectifier and inverter modules WYSIWYG: Test placement of components to check footprint accuracy. Connectors not shown. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504309065887-4K39IWIYYZHZ19DP6M5Z/rectifier_pcb_back Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Rectifier module interface PCB - back side https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504309618135-33NL46EFNT0AAWTEJU46/inverter_interface_schematic Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The inverter PCB interface schematic, showing connectors for DC-input (optional), motor output, gate driver connection, DC-link direct connection with discharge resistor and snubber circuit. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504309807495-MYXUDL3IANTSVKEWG049/inverter_interface_pcb Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The PCB layout of the inverter interface. Red tracks are on the PCB top side, while the green tracks are on the reverse side. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310200227-FM00DCRMXE3GRINO0BIS/inverter_pcb_3d_model Project Blog - Designing and producing interface PCBs for rectifier and inverter modules We thought this looked quite cool https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310264445-1C4BISLX28DPVRE4TL10/inverter_pcb_3d_model_backside Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The DC-link discharge resistor and the snubber components are through-hole components and thus has to be placed on the opposite side as the inverter module. The thermocouple connector is also placed here. The connecting rods between the PCB and capacitors might be too inductive, so that solution is not final. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310552201-Z08URI25J6NM3Y3DWXNL/inverter_card_pcb_manufactured_test Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The inverter module fitted perfectly. Let's hope the tracks are correctly routed... https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310586014-O08Y6OVZE9PDRF0HKDUX/inverter_card_pcb_cap_test Project Blog - Designing and producing interface PCBs for rectifier and inverter modules The tolerances for the capacitor terminals fits, but not perfectly. I forgot to take into account that they are not perfectly cylindrical when I designed the capacitor 3D-model. It was therefore no splendid idea to place them all the way next to each other with no space between. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310801148-BSCXNNZA5BF9OGDNFNQC/inverter_interface_pcb_front Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Inverter module interface PCB - front https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1504310778860-DD7B869HDQLC52ELXYJF/inverter_interface_pcb_back Project Blog - Designing and producing interface PCBs for rectifier and inverter modules Inverter module interface PCB - back https://www.switchcraft.org/project-blog/2016/12/20/design-of-a-current-sensing-pcb monthly 0.5 2016-12-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482260302440-TE53GVXEBTV9LUQPRYLL/image-asset.jpeg Project Blog - Design of a current sensing PCB The LEM LTS 25-NP current sensor. The measured current can either pass in a wire through the center hole, or connect to the main legs via circuit board paths. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482267525372-X4WRFUS4B2SVPREU2LAJ/Current_sensor_Full_schematics.png Project Blog - Design of a current sensing PCB The complete schematics for the current sensor card https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482275967039-6QEKP2FD23DBT0JLIA38/image-asset.png Project Blog - Design of a current sensing PCB The layout of the current sensing PCB. All tracks are routed on the bottom layer. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482274450499-X5CFLDDPLL0FE4ZHPVPL/Current_sensor_3d_top_view.png Project Blog - Design of a current sensing PCB https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482274450840-5KAQN0MF69U65CXTHCZQ/Current_sensor_3d_top_view2.png Project Blog - Design of a current sensing PCB https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482274449177-OI1LQR6QKVV68Z51KLNT/Current_sensor_3d_bottom_view2.png Project Blog - Design of a current sensing PCB https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1482274447658-5RF7S6M6AWE4NOI3S1TV/Current_sensor_3d_bottom_view.png Project Blog - Design of a current sensing PCB https://www.switchcraft.org/project-blog/2016/12/11/designing-a-voltage-sensing-pcb monthly 0.5 2016-12-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481629125753-8LF80BQ4RUEY792CBF8R/Jumper_settings_photo.png Project Blog - Step-by-step design of a voltage sensing PCB - Jumper settings Red Pitaya STEMboard 125-14: The two fast analog inputs with their SMA-connectors and jumper settings. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481629124195-942PIH9C3RU2Z127V5JJ/Extension_connector.png Project Blog - Step-by-step design of a voltage sensing PCB - Extension connectors Red Pitaya STEMboard 125-14, overview of extension connectors. Analog inputs and outputs shown on E2. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481629213977-JSN4NBF3FZ4JZW2HNEOI/ResistorNetwork.png Project Blog - Step-by-step design of a voltage sensing PCB - Resistor network According to the hardware schematics, this resistor network exist between the E2 analog inputs and the FGPA input. It rescales the voltage range from 0-3.5 V to +- 0.5 V which is the FGPA default input range. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481630860641-0K606694HTXSQXF1D0FU/image-asset.jpeg Project Blog - Step-by-step design of a voltage sensing PCB The selected ADC in the package "6 SOT23" https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481459282389-3TF4TFGKOYFQZIB6I0EX/image-asset.jpeg Project Blog - Step-by-step design of a voltage sensing PCB Front and back of the LEM LV-25 P voltage sensor https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481459341049-ZWV9OK4VMI1IP7EKNSG2/image-asset.png Project Blog - Step-by-step design of a voltage sensing PCB Internal circuit diagram of the voltage sensor https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481645666831-9JTHH4OYXAWAF8J595PE/Signal_schematic.png Project Blog - Step-by-step design of a voltage sensing PCB The signal path from left to right: Main voltage connection, step-down resistors, voltage sensor (U1), measurement resistor, opamp with potmeter for bias and scaling. The last plug is the output to ADC. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481656604986-M3YX9PHCCECN9PE0KHLJ/image-asset.png Project Blog - Step-by-step design of a voltage sensing PCB The PCBs voltage supply with filter capacitors. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481711669078-GLYBXOV2HMECO42N7022/image-asset.png Project Blog - Step-by-step design of a voltage sensing PCB Full schematic of the voltage sensing card. The opamp in the lower left corner is the second opamp in the opamp chip which is not in use. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481741503651-ZTNRISGV3M62LQQENKJM/VoltageSensingCard_Bottom_3D.png Project Blog - Step-by-step design of a voltage sensing PCB https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481741503371-PGPB8LZXH6LDRBPUBNW8/VoltageSensingCard_Top_3D.png Project Blog - Step-by-step design of a voltage sensing PCB https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481741516450-BBF937130EO1U0YAG7T6/VoltageSensingCard_Top2_3D.png Project Blog - Step-by-step design of a voltage sensing PCB https://www.switchcraft.org/project-blog/2016/12/9/main-component-overview monthly 0.5 2016-12-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481311398705-R75J0R90H0PAOYDVYJBV/Semikron_sk95dgl126_rectifier_bridge Project Blog - Main component overview The chosen rectifier bridge; Semikron SEMITOP® 3 SK 95 DGL 126 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481311444250-4N779U0YF93T675TYDI7/Semikron_sk95dgl126_rectifier_bridge_diagram Project Blog - Main component overview The diagram showing 6 rectifier diodes to the left and a brake chopper IGBT-transistor with blocking diode to the right. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481312042639-YPBGT6GLTICZ45UNRZPD/Semikron+SEMITOP%C2%AE+3+SK+95+DGL+126 Project Blog - Main component overview Two pieces of a 95A rectifier bridge. Might need some forced cooling to dissipate heat from such amounts of current. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481312177950-3R8TB6PYJABHWC5SB123/semikron_miniskiip_skiip_13acm12v18 Project Blog - Main component overview The chosen transistor bridge; Full SiC, MOSFET-based SKiiP 13ACM12V18 from Semikron https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481312223795-RPW8HEFU7HD0AJ4Z9OII/semikron_miniskiip_skiip_13acm12v18_diagram Project Blog - Main component overview The diagram for the inverter bridge, with the three phased output to the right. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481312301740-GVWASUZ9NWKH3673AU9U/semikron_miniskiip_skiip_13acm12v18_arrived Project Blog - Main component overview Two pieces of transistor bridges. One for Yngve and one for Eirik. Sharing is caring, but to share a transistor bridge is not very funny. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481312727850-9MFCHUI7B7TMK8BRLQPZ/two_500V_18000uF_capacitors Project Blog - Main component overview These are huge. In both rating and physical size. https://www.switchcraft.org/project-blog/2016/12/8/stemboard-hello-world monthly 0.5 2017-03-14 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481233734013-PMMQL039GXSVKN1HOO8X/image-asset.gif Project Blog - STEMboard "Hello World" LED lights, Night Rider style https://www.switchcraft.org/project-blog/2016/12/8/red-pitaya-quick-start-guide monthly 0.5 2016-12-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481201524095-M5OALI5CJQ0K8PQIJGS2/RedPitayaQuickStartGuide Project Blog - Red Pitaya STEMboard Quick Start Guide The attached quick start guide which didn't contain all the necessary parts of information after all. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481203621616-3HZFCW9Q0MPZ3HIAJT5B/RedPitayaPowerConnector Project Blog - Red Pitaya STEMboard Quick Start Guide There are two micro USB-ports, one for data and one for power supply. This is indicated by the text CON and PWR respectively on the cards backside. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481201750481-B82NDXOSVDG7AWUPIRJX/RedPitayaGreenLight Project Blog - Red Pitaya STEMboard Quick Start Guide A single green light should indicate that everything is all right, right ? https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481201878024-UOOINLZUU4S7MUYJHVMX/RedPitaya.com404 Project Blog - Red Pitaya STEMboard Quick Start Guide whoops. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481202222537-D6I73EZBW9Z08YCNTU9F/RedPitayaWithSDcard Project Blog - Red Pitaya STEMboard Quick Start Guide Note to self: Insert SD card prior to booting the STEMboard. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481202473457-RLZOU7WWOT8W1GZPU7ZQ/RedPitayaGreenAndBlueLight Project Blog - Red Pitaya STEMboard Quick Start Guide More lights = more success. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481203409387-B2Q7P9PSL2X56EK1ARTC/RedPitayaLocalPage Project Blog - Red Pitaya STEMboard Quick Start Guide The STEMboard's web page which features a bunch of possibilities for measurements etc. https://www.switchcraft.org/project-blog/2016/12/7/red-pitaya-controller-arrived monthly 0.5 2016-12-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481120184464-FYQNUEKNOZDRXLB6G0V4/RedPitayaBoard Project Blog - Red Pitaya Controller arrived the Red Pitaya STEM-board It is *really* tiny. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481120246024-5UH6FA6HAS0HAGB9OY4I/RedPitayaKit Project Blog - Red Pitaya Controller arrived The diagnostics kit contains two measurement probes (60 Mhz), a 4 GB memory card and two adapters (SMA to BNC). https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481140999375-POKSH3ODXBVPE4DL6800/RedPitayaOverview Project Blog - Red Pitaya Controller arrived Overview of the main features of the STEMlab 125-14 https://www.switchcraft.org/project-blog/2016/12/7/motor-drive-project monthly 0.5 2016-12-20 https://www.switchcraft.org/project-blog/2016/12/6/genesis monthly 0.5 2016-12-20 https://www.switchcraft.org/project-blog/category/Motor+Drive+Project monthly 0.5 https://www.switchcraft.org/learning daily 0.75 2019-07-05 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481741173193-BL7PKQWIU4ACUCFO9VUH/Learning-banner.png Learning https://www.switchcraft.org/learning/2016/12/9/gate-drivers monthly 0.5 2017-07-26 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481636866851-N265HH8ANTLYEZDR70LJ/image-asset.png Learning - Gate drivers Simplified schematic of a typical gate driver output stage https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481634462844-I234AJIFAYRC92ZI6X8O/image-asset.png Learning - Gate drivers Overvoltage protection by clamping the gate to the supply with a Schottky diode. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1501013897951-Z0WIHHUMO0VED8PA52G9/image-asset.jpeg Learning - Gate drivers https://www.switchcraft.org/learning/2017/6/26/pwm-challenges-part-2-bearing-currents monthly 0.5 2017-06-26 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498471238118-PQ64YCC1QB458BOR37V0/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Figure 1: Bearing currents with ground return in an electrical machine [2]. \( C_g \) corresponds to the capacitance across the bearing while \( C_{ws} \) and \( C_{wr} \) corresponds to the per unit length parasitic capacitance from the winding to the stator and rotor respectively. \( Z_{inv} \) is the (mainly) capacitive coupling from the inverter to ground. \( \label{fig:bearing_current} \) https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498473450698-MGB5IX5W9TA2FKREA6RI/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Figure 2a: Stray capacitances between winding and stator iron which cause capacitive ground currents and subsequent non-uniform current density. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498473496273-NM66C7H81EY0LHL6WD5H/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Figure 2c: Cross-sectional view of the machine where the net flux path of the enclosing magnetic field is show in red. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498473475080-KKL0FJ050506YOUKPSDY/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Figure 2b: Current density as function of winding length from terminal.   https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498473517251-D7KMCTRFLNI8O0FU0H16/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Figure 2d: Side view of the machine where the circulating bearing current is shown in red. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1498474350416-MDU7RUOX4J9WLAAEYF0X/image-asset.png Learning - PWM Challenges Part 2 - Bearing Currents Zero sequence voltage (\( V_0 = _{ph_gnd}\) ) in PWM inverter drives [3] https://www.switchcraft.org/learning/2017/3/15/space-vector-pwm-intro monthly 0.5 2021-01-28 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1537207349252-DQR4QNU0ZOSWADVRR1VR/3ph_fixed_animate.gif Learning - Space Vector PWM Intro An ordinary three phased system, here shown in both vector form and in sinusoidal form. The black vector is the resultant space vector; a vector sum obtained by adding the three vectors. As can be seen, the space vector's magnitude is always constant. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1495979634191-IJUTF9ERVVJDQNI2VXAB/image-asset.png Learning - Space Vector PWM Intro The schematics of a two-level inverter with passive diode front-end, DC-link capacitor and a motor equivalent connected. Snubbers and anti-parallel diodes are not shown. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493076837720-B4YIZ3RWDPSW1SUARDWI/image-asset.png Learning - Space Vector PWM Intro The simplified version of a two level inverter. The DC-link is now assumed constant so that the diode rectifier is omitted. Further, it is assumed that each inverter leg has one of two transistors closed at any given time. In this example, Leg W has the upper transistor closed while Leg V and U has the lower transistor closed. The arrows indicate current direction. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493079710127-7UYIAWGDH3QMYN47G517/Basic-Vectors.png Learning - Space Vector PWM Intro The eight basic vectors with their magnitude and direction. The zero vectors \(v_0\) and \(v_7\) are shown at origo. The U-phase is normally basis for all angles. The origin of the angles are the windings physical location inside the stator; installed around the circumference at 120° apart. Because each winding can have positive and negative voltage, it occupies two angles at 180° separation. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080041150-CVHGO3PM2A6X2C5D6RWD/PowerElectronics-000.png Learning - Space Vector PWM Intro - v0 - 000 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080041661-9SIL74GRWU4ESQY6LK1U/PowerElectronics-001.png Learning - Space Vector PWM Intro - v1 - 001 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080042255-9GSX6Z47J6M9OLRVA38P/PowerElectronics-010.png Learning - Space Vector PWM Intro - v2 - 010 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080041040-ED9A5RZCQ8K5M5CAQ1C5/PowerElectronics-011.png Learning - Space Vector PWM Intro - v3 - 011 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080042698-PPR4A6PGLY1HKIVJKH9G/PowerElectronics-100.png Learning - Space Vector PWM Intro - v4 - 100 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080041558-TBY3F0C7QSKCXQ4GRHTS/PowerElectronics-101.png Learning - Space Vector PWM Intro - v5 - 101 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080042795-LEB2GC9KA7KPTQK06XN5/PowerElectronics-110.png Learning - Space Vector PWM Intro - v6 - 110 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493080042151-4SWVFT93QRVK9Q2EMQMS/PowerElectronics-111.png Learning - Space Vector PWM Intro - v7 - 111 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493083848914-OUPPOIAC5N3DK0B2IN7M/Basic-Vectors-with-reference.png Learning - Space Vector PWM Intro A voltage reference between the basic vectors 1 and 3. Rapid alternations between these to vectors along with the zero vectors can emulate the reference voltage. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084456915-RDN7O3Z8G6W0Y35T31P3/SVPWM-1.png Learning - Space Vector PWM Intro - Sector 1 - 18° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084456541-BN3S65DZJ8N4GD717KFM/SVPWM-2.png Learning - Space Vector PWM Intro - Sector 2 - 95° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084455047-OU07LBQJMGATHTRBEVCX/SVPWM-3.png Learning - Space Vector PWM Intro - Sector 3 - 150° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084455616-FECKYZYTOTJVF8WGFHXJ/SVPWM-4.png Learning - Space Vector PWM Intro - Sector 4 - 189° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084456140-RLOKTO61DTIPE5LC6U7D/SVPWM-5.png Learning - Space Vector PWM Intro - Sector 5 - 285° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493084457375-F597Q58SXQY8X5ORHHTL/SVPWM-6.png Learning - Space Vector PWM Intro - Sector 6 - 347° https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1494290418343-YQC46SITF6ALZ3JR886X/image-asset.png Learning - Space Vector PWM Intro Part 1 - The input which shows the desired output voltage and a trig wave used to determine the vectors used and their on-time. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1494290473114-CUDL6PRUEX2LNOGKTIQF/image-asset.png Learning - Space Vector PWM Intro Part 2 - The trig wave and how it visually translates into three binary digits. Here, 000-001-011-111 in the four different sections of the halv period. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1494290533415-VGS4AKIRYSKEGWWNF8Z3/image-asset.png Learning - Space Vector PWM Intro https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1494290617133-J5QN9K3DTTPIJF8XVCFQ/image-asset.png Learning - Space Vector PWM Intro https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493085514196-SJ9AGSE5JSO8YKNGOMGG/image-asset.gif Learning - Space Vector PWM Intro https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493597286746-P65QZHJPMA9YIHYIGRRM/image-asset.png Learning - Space Vector PWM Intro The famous space vector hexagon showing each of the basic vectors and their magnitudes along with a reference vector at 30° which has a maximum linear magnitude. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493600222348-XIK3DBFLUOGXJPHAJ05Y/image-asset.png Learning - Space Vector PWM Intro A standard two-level inverter shown with its maximum output voltage waveform in red. The dashed curve represent the desired voltage, i.e. same amplitude as the input rms voltage. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493601127246-RZ1D8MHXLRUJAST8MX98/image-asset.png Learning - Space Vector PWM Intro Third harmonic injection; hidden inside the blue waveform is a fundamental sine wave with amplitude above the DC-link voltage. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493601813334-CPTACFADJRNX7BTVKVXF/image-asset.png Learning - Space Vector PWM Intro The third and fundamental harmonic exposed, revealing the increased amplitude. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493602734320-64W5XS8F54VD032L281U/ThirdHarmonics.png Learning - Space Vector PWM Intro Three phases with their first and third harmonics. Note that the third harmonic (black) is common to all three phases. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493604197177-TJHAIRL7V3FF1BCBDLVL/image-asset.png Learning - Space Vector PWM Intro A volt-meter connected to the phase-neutral points of a motor. This will reveal the motor winding voltage and if the third harmonics will have any effect on them. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1493611848540-BEFVDBFEPMC6L9TLBFPX/image-asset.gif Learning - Space Vector PWM Intro The voltages as function of modulation index m. A smooth sine wave can be synthesized with 0 < m < 1.154 by use of third harmonic injection. https://www.switchcraft.org/learning/2017/3/29/three-phase-ac-system-basics monthly 0.5 2017-10-20 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496951009340-JNC8L7XHXQ1APVPAZDWP/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496951039125-T7B8WWHDWDRY7QOA6RC9/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496924044846-4SJTBRTQHBPNY3ULKD56/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952092195-HSRTBUMX7CCVIK0UCC2M/voltage-current-0-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952079087-XJU8XXQ3FOB2TEY0AXUT/power-0-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952128781-SVT2FZJI3B3X00CVL9S2/voltage-current-90-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952160890-MV7QW464PBVRRJ75UEDE/power-90-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952199209-LOGDZHJ0Q59BQO77GE96/voltage-current-120-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496952206636-8PCXLLUET6YKIW5V1VDL/power-120-deg.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496924172965-YTV5JD66GHCA4SUXEOUT/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496924203598-CWPSSL2FJ8ZHNF6FC8YB/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496925540269-NMOALGD2BPZ0XKTWMCBW/image-asset.png Learning - AC system basics https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1496928704078-0VKV8VW1M6P22RT0N4C3/image-asset.png Learning - AC system basics https://www.switchcraft.org/learning/2016/12/16/vector-control-for-dummies monthly 0.5 2018-09-23 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483099894144-NR00P1MHEL02Z4NNWHW4/image-asset.png Learning - Vector control for dummies The Clarke transform creates two orthogonal currents from a three phased measurement. The two new currents represent torque producing and magnetic field producing currents. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483099919308-34FFKA3UXU25X7ACFMCT/image-asset.png Learning - Vector control for dummies The Park transformation takes the step from a stationary reference frame where the currents seem sinusoidal to a rotating reference frame. The rotating movement is taken into account to compensate the sinusoidal currents and hence transform them to DC values. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489537741306-NATZ2E1P9UUWVLU2B574/image-asset.png Learning - Vector control for dummies The basic workflow of vector control. Note that the voltage output is based on SV-PWM with third harmonic injection which is causing the non-sinusoidal shape. This technique will be explained in a separate article. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483101071316-KBVLAK06CBE1V76MBB3E/ClarkePark_Animation Learning - Vector control for dummies The animation above illustrates the Clarke-Park-Transformation with a rotating vector arrow, decomposed three- and two-phased vectors and a scope view of the corresponding sine waves. https://www.switchcraft.org/learning/2017/1/5/teardown-of-a-commercial-motor-drive monthly 0.5 2017-01-06 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483646136108-RB28GFEPKGTIV2RMWBW2/image-asset.jpeg Learning - Teardown of a commercial motor drive The circuit board is clearly damaged by the heat from some kind of component failure. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483647212095-6SINORUQBGL2U55YDD9W/image-asset.png Learning - Teardown of a commercial motor drive Redrawn diagram of the main power circuit. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483646293896-H1PCBCRHVJ6UJ0EUMEUT/image-asset.jpeg Learning - Teardown of a commercial motor drive Inverter power circuit board. The large capacitor to the right is the main reservoir capacitor, while the inrush limiting NTC is the black body just above the capacitor. The rectifier and inverter modules are visible at the top left and right respectively. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483660917256-3Z0DPW4U4RIXUXU0HBVQ/main-circuit-board-top-view.jpg Learning - Teardown of a commercial motor drive The IDC connector at the top is used to interface with the controller board. The PLCC chip located below the connector is the gate driver to the IGBT module. The relay next to the reservoir capacitor is used to bypass the inrush limiting resistor. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483660929821-RZSG8T24S63R5BQAFW1B/inverter_power-components.jpg Learning - Teardown of a commercial motor drive Viewed from a different angle, the attachment of the power modules to the heat-sink is visible. The wire attaced to the heat sink just above the modules is a temperature sensor. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483646813828-13HUNNWBA8Y8KN2BWQHY/image-asset.jpeg Learning - Teardown of a commercial motor drive Input filter to the rectifier. The two yellow bodies contains the common mode input chokes. The blue component to the left is a metal oxide varistor to protect the input from overvoltage. The other blue components are various sizes of capacitors. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483646690987-B1631VBYM5X2G7X181AI/image-asset.jpeg Learning - Teardown of a commercial motor drive Filter choke consisting of two separate inductors wound on the same magnetic core. The black plastic piece in the middle separates the two inductors. Two wires are used in parallel, in order to increase the current carrying capability. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483661269419-IIEWIUFN998CAD9H5CCK/dc-dc-converter-top.jpg Learning - Teardown of a commercial motor drive https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483661275367-GQODBUSB3LPZ3B7BIM56/dc-dc-converter-bottom.jpg Learning - Teardown of a commercial motor drive https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483660162566-KOFN2OYYT723T5TG2RFJ/controller-board.jpg Learning - Teardown of a commercial motor drive Controller board. The TQFP packaged chip is the controller. The screw terminals at the top are available for connection of external I/O. The blue component to the top right is a relay used for digital output. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483660527526-BEPO7BWULOSKCSLJAIOR/controller-board-bottom.jpg Learning - Teardown of a commercial motor drive Bottom view of the controller circuit board. The SOIC(Gull-Wing) packaged chips are opto-couplers most likely used for the digital I/O. https://www.switchcraft.org/learning/2016/12/30/circuit-simulation-with-qucs monthly 0.5 2016-12-30 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483100530829-986PL0380LKODEWLHNIU/image-asset.png Learning - Circuit simulation with QUCS DC-simulation of a simple voltage divider. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483100807111-ZVVZD0S7OFNLOB4DQ4V8/image-asset.png Learning - Circuit simulation with QUCS DC simulation including annontation of the currents https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483104296142-BVKWRMXDDJRYTA0TJRLW/image-asset.png Learning - Circuit simulation with QUCS The output characteristics of the transistor obtained by using a dual parameter sweep. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1483105227704-5S0L8OVD2SZMOU8H8DKW/image-asset.png Learning - Circuit simulation with QUCS Output characteristics of low-pass filter obtained by AC frequency sweep. https://www.switchcraft.org/learning/2016/12/9/challenges-using-pwm-in-motor-drive-applications monthly 0.5 2017-06-22 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481800613228-9Y7184CMKULEII5GYN00/image-asset.png Learning - PWM Challenges - Part 1: Voltage reflections A so-called line equivalent showing a cable or conductor's parasitic elements per unit length, \( \partial x \): DC resistance \( \partial R\), inductance \( \partial L \), capacitance to ground \( \partial C \) and conductivity to ground \( \partial G \) https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481715025425-VKZ9AN5IV46JZKADQZ33/image-asset.png Learning - PWM Challenges - Part 1: Voltage reflections Figure 1: Lattice diagram explaining voltage reflection theory https://www.switchcraft.org/learning/2016/12/10/transformer-and-inductor-design monthly 0.5 2018-04-07 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481736238383-A5YDUBT2JUGL4IXDRXHW/transformer-ch.png Learning - Transformer and inductor design Schematic symbol for a simple transformer. The vertical lines indicate a solid iron core. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481814406701-2NGX6K9E8DBLMTXG3DC4/image-asset.png Learning - Transformer and inductor design Transformer equivalent circuit https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481754759048-NK1RLOHRBJVBL9OGWB2U/image-asset.jpeg Learning - Transformer and inductor design Transformers: More than Meets the Eye. https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481568849268-UTB3DBV9ID5GIPZCK1OD/transformer-example.jpg Learning - Transformer and inductor design The transformer core used in the example. https://www.switchcraft.org/learning/2016/12/9/si-vs-sic-devices monthly 0.5 2016-12-09 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481287097355-6PZXSI24X1RTJ3K3145D/image-asset.png Learning - Si vs SiC devices Si diode turn-on https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481287116646-ETRQDK35JDHMBF2H4ZLM/image-asset.png Learning - Si vs SiC devices SiC SBD turn-on https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481287644991-7KL06UDULYAEUAKO9JS9/Si_turnoff.png Learning - Si vs SiC devices Si diode turn-off https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481287596065-F0S1RO5YG02O6LY7E50L/SiC_turnoff.png Learning - Si vs SiC devices SiC diode turn-off https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481288508031-QPOJ3Z5VK1VMZFVZXRA2/image-asset.png Learning - Si vs SiC devices Figure 3: An exploded IGBT power module showing the bottom circuitry with transistors (squares with black edges) and anti-parallel diodes (gray squares). https://www.switchcraft.org/learning/2016/12/8/isolated-current-measurement monthly 0.5 2017-07-14 https://www.switchcraft.org/learning/category/Semiconductors monthly 0.5 https://www.switchcraft.org/purpose daily 0.75 2017-03-14 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1481308878273-XN68KDTNEE4KN9QMW6BA/Singapore_storm_Asbj%C3%B8rn.jpg Purpose https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489454116000-9TLFSIL1LT394HPH7D9Y/Eirik.jpg Purpose - Eirik https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1518286968532-V6J21Z57WYGOPHKXKX7M/Yngve_sh+5.JPG Purpose - Yngve https://www.switchcraft.org/about-us daily 0.75 2017-05-10 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489457030380-6IA1ZKKZ0FIDUSVKVEQI/P2061439.JPG Authors https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489455799000-BA066NIOKVZ1Z0OF5BRO/Eirik_ntnu Authors Eirik and some of our classmates from the university https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1489456962708-8XN34HJNR8O6A3CCYKY8/Yngve_something Authors Yngve, minutes after submitting his master's thesis. https://www.switchcraft.org/project-description daily 0.75 2016-12-09 https://www.switchcraft.org/tip-jar daily 0.75 2018-09-02 https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535888605517-W52G5OYRWTITSNT6RS77/Knowledge-sharing.jpg Tip Jar https://images.squarespace-cdn.com/content/v1/584729023e00bebf8abd6ba0/1535886955087-O39MVUKTD716OZB5RKTV/tipjar Tip Jar