Team MotorBoard Efficient Motor Control and Power Conversion System Critical Design Review 24 February 2009 Nicholas Barr, Daniel Fargano, Kyle Simmons, Marshall Worth Overview Purpose & Specifications System Description Controller Circuit Power Converter Other parts and purchases Updated Labor Distribution Updated detailed schedule Questions/Suggestions and Comments Purpose and Specifications Provide a general purpose motor power system and controller More specifically will be used in the IEEE Future Energy Challenge ‘09 30 N-m Cold Torque 3000 Rpm 3-5 seconds 1 KW Power NEMA Frame 56 Motor Requirements Torque Characteristics System Description Control System • Arm7 Microcontroller • Built in PWM • Gate Drivers for IGBTs Power System • Bi-Directional BuckBoost Converter, more efficient by isolating the buck and boost sections • 3-Phase Voltage Inverter System Diagram Control System NXP LPC2148FBD64-S LPC-P2148 Olimex devo board Crossworks-ARM • Program Memory Size: 512KB • RAM Size: 40KB • Package / Case: 64-LQFP • Speed: 60MHz • Core Processor: ARM7 • Data Converters: A/D 14; D/A 1 • Core Size: 16/32-Bit • Interface: I²C, SPI, SSP, UART, USB Control Algorithm The objective of the controls algorithm is to sense a set of The objective of the inputs from the controls algorithm is to motor and sense a set of inputs from the motor and control board control board and and produce a produce a corresponding 3-phase output voltage. corresponding 3-phase output voltage. First we sample the current and voltage at phase A,B and C of the motor as well as First sample the theweDC-DC current in phase A,B and output C as well as voltage. the position and speed of the rotor Additionally we shaft sample the position and speed of the rotor shaft. Second we determine the motor Second we determine operating the motor operating mode, motoring mode and or generating, and the the desired desired speed of operation. speed of operation. From these Finally the controller quantities will determine the the desired appropriate duty cycle Finallyon the the controller DC-DC to emit IGBT will determine the converter gate drivers’ input appropriate duty cycle toin emit on the IGBT gate From these quantities order to produce the output driver input in order to the desired DC-DC produce the desired voltage converterand output voltagedesired voltage at both voltage at both the and phase phase A,BA,B and C the output DCoutput of of the the DC-DC voltages are calculated. converter as well as the and C DC converter as well as phase A,B and C voltages voltages the phase A,B and C produced by the inverter. are voltages produced by calculated. the inverter. Vector Controller Clark Transform isa isb isc 0 _ is k (isa aisb a 2isc ) 2 3 a e j 2 / 3 , a 2 e j 4 / 3 k _ is is jis 1 1 is k (isa isb isc ) 2 2 3 is k (isb isc ) 2 Park Transform d sd s sq dt d u sq Rs isq sq s sd dt d urd 0 Rr ird rd ( s ) rq dt d urq 0 Rr irq rq ( s ) rd dt sd Ls isd Lmird u sd Rs isd sq Ls isq Lmirq rd Lr ird Lmisd rq Lr irq Lmisq te 3 p p ( sd isq sqisd ) 2 PWM CrossWorks Code written for Development board using CrossWorks Power System 195VDC line to supply from variable AC source Large DC supply line capacitor Bidirectional Buck-Boost Converter Bidirectional DC 3phase AC inverter Power System - Overview Power System – Cascaded B/B Power System - 3φ Inverter Power System – Switches Power MOSFET high-frequency operation low-voltage drop (low power losses) saturation temperature sensitivity IGBT low drive current fast switching time higher voltage drop (higher conduction losses) IGBT w/Diode Co-pack Voltage - Collector Emitter Breakdown (Max):600V Current - Collector (Ic) (Max):85A Power System – Driver Configuration:High and Low Side, Independent Bootstrap circuit designed to prevent gate voltage from dropping below minimum gate threshold voltage Power System – Driver DC-DC Bi-Directional Buck-Boost Simulated 3 Phase Waveforms Simulated 3 Phase Waveforms Sensors 3 Hall-effect current sensors for a,b,c line detection • After attending APEC Dan needs to call his contact at GMW or TEG to get free Hall Effect Sensors Quadrature encoder (fancy shaft encoder) • Most likely optical • Prefer absolute position sensor • Old team lists having this and could possibly find and use theirs DC line voltage sensor • APEC -> Call TEG for possible free sample • Resistor Divider Network (Power Loss) Optional (safety): • Temperature sensor Parts List – Mass Production Item Part # Quantity Unit Price Total Price Mass Production Cost Caps 495-3502-ND 4 9.35 $37.4 $8.35 Inductors M8380-ND 1 9.56 $9.56 $1.39 IGBTs IRG4PSC71U 10 DPBF 10.68 $106.80 $18.70 Drivers IR21132PBF-ND 5 5.57 $27.85 $5.96 Bootstraps XXX 5 1.19 $5.95 $1.49 MPU 568-1765-ND 1 11.20 $11.20 $2.80 Controls XXX 1 31.76 $31.76 $7.94 Motor Baldor 1 326.90 $326.90 $50 Package XXX 1 18.20 $18.20 $3.64 $574.54 $100.00 Total Division Of Labor Converter • Nick • Marshall PCB Design • Dan • Marshall Custom Footprints • Kyle • Dan • Marshall Inverter • Dan • Kyle Testing • All Software • Nick • Marshall Documentation • All Presentation • All Project Milestones Milestone I Milestone II • Power Electronics hardware working on perf-board • Controls driven by Dev Board (no feed back loops) • First revision of controls PCB completed and sent out. • Power electronics PCB designed and sent out for fabrication • Controls PCB built and populated • Full controls algorithm with working feed-back loops. EXPO • Final debug finished • Packaging designed done and project packaged • Documentation done Questions?