Sensorless BLDC Control with Back-EMF Filtering Using a ...

1 2008 Microchip Technology - 1AN1160 dsPIC (DSC) BLDC ( DC) (BEMF) 3 6 dsPIC ADC (Analog-to-Digital Converter) BEMF BEMF BLDC dsPIC DSC BEMF dsPIC DSC ADC BLDC BLDC BLDC BLDC 1 (BEMF)

2 BEMF BEMF BEMF :Daniel TorresMicrochip Technology Inc. BLDC AN1160DS01160A_JP - 2 2008 Microchip Technology ( ) 6 (120 ) 1 6 ( ) 60 6 360 1 1:6 6 6 ( ) 6 1 1- - - 2- - - 3- - - 4- - - 5- - - 6- - - ( ) 2 1 1 6 1 (RPMElec) 1 (RPSElec) (RPMElec) (RPMMech) 3 1: RPM 2.

3 RPM RGB15462360 123456 Blue WindingGreen WindingRed WindingSector+VBUS-VBUS+VBUS-VBUS-VBUS+V BUSRPMMech2 RPMElec ---------------------------------------- --=RPMElecRPMMech 2--------------------------------------- -----------------------------------= 2008 Microchip Technology - 3AN1160 3:RPS RPM BEMF BLDC BEMF ( ) BEMF BEMF 3 ( ) BEMF 4 4: (BEMF) 4 BEMF BEMF BEMF BEMF ( ) BEMF BEMF - ( DC )

4 -Y - 4 3 - - BEMF BEMF BEMF BEMF BEMF dsPIC DSC 1 BEMF Y 3 3 1 BEMF 1 2 2 BEMF ( 2 ) 2: RPSElecRPMElec60------------------------ -=BEMFNlrB = N = l = r = B = = 501234501 SECTOR000= BEMF Zero Crossing30 AN1160DS01160A_JP - 4 2008 Microchip Technology Inc.

5 1 6 60 1 ( ) BEMF 30 2 BEMF BEMF 3 BEMF BEMF BEMF 2 BEMF DC 2 1 BEMF VDC/2 BEMF DC 2 1 3 3:BEMF DC 2 1 1 1 A +VBUS C -VBUS B B BEMF 2 +VDC B 2 +VDC B +VDC A C -VDC A BEMF 3 -VDC B A VDC/2 3 BEMF VDC VDC/2 BEMF 3 4 4.

6 BEMF ACBDC+DC-DC/2+_Back-EMFTo IC2 ACBDC-Virtual Neutral+_Back-EMFTo IC2 2008 Microchip Technology - 5AN1160 BEMF 5 5: BEMF BEMF BEMF 5 ADC BEMF ADC PWM BEMF 6 BEMF 7 BEMF BEMF dsPIC DSC BEMF 5:dsPIC DSC ADC BEMF VnBEMF ABEMF BBEMF C++3------------------------------------ ---------------------------------------- = Vn BEMF A A BEMF BEMF B B BEMF BEMF C C BEMF 3-PhaseInverterPWM3 HPWM3 LPWM2 HPWM2 LPWM1 HPWM1 LFLTAF aultBLDCdsPIC30F2010AN3AN4AN5AN2 DemandPhase Terminal Voltage FeedbackR49R41R34R36R44R52AN1160DS01160A _JP - 6 2008 Microchip Technology Inc.

7 6:PWM 100% BEMF 7:PWM 100% BEMF APHASE BPHASE APHASE BPHASE CRECONS 2008 Microchip Technology - 7AN1160 BLDC dsPIC30F PICDEM MCLV ( 8 ) Hurst DMB0224C10002 CL B 6403 24V BLDC 24 V 8:PICDEM MCLV AN1160DS01160A_JP - 8 2008 Microchip Technology dsPIC33FJ12MC202 PIM Explorer 16 PICtail 3 dsPICDEM MC1L Hurst DMB0224C10002 CL B 6403 24V BLDC 24 V 9:dsPIC33F We b 2008 Microchip Technology - 9AN1160 5 5 MCLV 1 1.

8 MCLV MCLV Pot R14 dsPIC DSC ADC AN4 BEMF R34/R36/R35 R41/R44/R42 R49/R52/R50 BEMF A B C ADC AN3 AN4 AN5 BEMF BEMF C17 C19 C21 Fault (U7D) (R26) pot R60 5 dsPIC33FJ12MC202 dsPIC33FJ12MC202 PIM 2 2:PIM Explorer 16 3 3:EXPLORER 16 PICtail 4 4: PICtail JumperSettingJ8 OpenJ10 OpenJ12 OpenJ14 OpenJ19 OpenJ7 Short in position 2 - 3J11 Short in position 2 - 3J13 Short in position 2 - 3J15 Short in position 2 - 3J16 ShortJ17 ShortResistorSettingR29, R30, R8, R6, R20, R31, R27, R25, R9, R7, R5 Not populatedR15, R16, R17, R18, R19, R32, R33, R14, R10, R23, R22, R21, R28, R26, R24, R13, R11, R12 PopulatedHardware modificationSettingJumper JP2 ShortJumper J7 Short in position PIC24 Switch S2 Short in postion PIMR esistors R50, R51, R52 Not populatedJumperSettingJ12, J11, J10 OpenJ1, J4 OpenJ14, J15, J16 OpenJ17 ShortJ6, J7, J8 OpenJ13 OpenAN1160DS01160A_JP - 10 2008 Microchip Technology dsPICDEM MC1L 37W_DTYPE_PLUG LK 5 5.

9 3 dsPICDEM MC1L ( ) BEMF n 3 2 ( ) 2 (3 ) 66% (> 50%) 6 3 6:3 2 6 AND ( ) OR ( ) 6: BEMF BEMF dsPIC DSC BEMF BEMF dsPIC DSC ADC PWM BEMF dsPIC DSC ADC 20 kHz ADC PWM dsPIC DSC ADC PWM ON PWM ON dsPIC DSC PWM ON 50%( )

10 BEMF PWM PWM 100% PWM ON 75% 10 11 BEMF A B C BEMF BEMF : PCB 5 3 dsPICDEM MC1L Section Accessingthe System LK 51 resistorsSettingLK22, LK24, LK25, LK26, LK30 PopulatedLK19, LK20, LK21, LK23, LK27, LK28, LK29, LK31, LK32 Not populatedABCM ajority11111101101110000111010000100000 AB ()AC ()BC () = 2008 Microchip Technology - 11AN1160 BEMF 20 kHz BEMF BEMF 10: 80% BEMF PWM SignalBEMF SignalBEMF Sampling PointAN1160DS01160A_JP - 12 2008 Microchip Technology Inc.