BLDC原理与驱动.ppt

,BLDC MOTOR 原理与驱动2007.11.16,一、MOTOR的种类二、BLDCM的构造三、直流变频的种类四、BLDC120度驱动原理五、BLDCM在空调中的应用,CONTENT,CONTENT,Category of BLDC Motor,#note 1.PMSM:Permanent Magnet Synchronous Motor 2.BLDC:Brushless DC 3.BLAC:Brushless AC 4.SRM:Switched Reluctance Motor 5.SynRm:Synchronous Reluctance Motor,Motor,AC Motor,DC Motor,InductionMotor,SynchronousMotor,UniversalMotor,PMMotor,Single PhaseThree Phase,PMSM(BLDC,BLAC)SRM SynRm,Rotate,Linear,Category of DC Motor,Inner Rotor Type,Outer Rotor Type,Rotor,Stator,Magnet,Shaft,Coil,Structure of BLDC Motor 1,Structure of BLDC Motor 1,Structure of BLDC Motor 2,Winding 绕制,Structure of BLDC Motor 2,Structure of BLDC Motor 3,Magnet 分布,IPM 构造,日立/Sharp,松下/LG/SS,Ferrite(4EA),Ferrite(6EA),Daikin,三洋,Nd(4EA),Nd(8EA),東芝,三菱/松下,Ferrite(4EA),Ferrite(8EA),Structure of BLDC Motor 3,直流变频的种类-特点,120度：方波/矩形波/梯形波180度：正弦波/矢量控制,Rectangular(120deg),Sinusoidal(180deg),Currentwaveforms,Low,High(12%),Efficiency,High,Low(23dB(A),Noise,Easy to implement-Back EMF(open phase voltages)-Low resolution of rotor position:60deg,Complex to implement-Estimator(voltages&currents)-High resolution of rotor position:3 32deg,Positiondetectingalgorithm,Low(8090Hz)-Small flux weakening-Maximum current lead angle:1015deg-Voltage control,High(120130Hz)-Large flux weakening-Current lead angle:not limited-Current control(torque control),Maximumspeed,Motor voltage(open phase),Motor current-3 current sensor(Shunt resistor)-Single current sensor(DC Link),Sensing,Micom(16bit),DSP/Micom(DSP function),Processor,Rectangular(120deg)/Sinusoidal Currents(180deg),直流变频的种类-波形与力矩,180sinusoidal drive control,120rectangule drive control,【正弦波驱动优点】损失降低，噪音降低过负载提升(位置Sensorless驱动时）电流位相调整容易（Vector控制）Torque/电流比最大控制 电压饱和时控制,MOTOR控制需要用正弦波！,直流变频的种类-驱动方式比较,BASIC BLOCK of INVERTER,BLDCM驱动原理-Basic Block,A,六个开关管交替导通,任一时刻,只有两相导通,BLDCM 120度驱动原理-导通顺序,以此类推,BLDCM驱动原理-启动方法,五步启动法：占空比与时间值存入EEPROM,反电势=位置信号=30度时间=换向,反电势,反电势,BLDCM驱动原理-换向,换向,120度通电:对其中两相通电，第三相会产生反电势；,+I,-I,N每相绕组的圈数;l转子的长度;r转子的半径;B 转子的磁通密度；电机的角速度,关系式：,特征：在任一相的反电势过零点，都有反电势Ea+Eb+Ec=0;在同一通电周期内，每相有两个反电势过零点；位置检出信号对基准位相（线间电压0)为30度领先）；,BEMF 的产生及特征,BLDCM驱动原理-BEMF检测,A,B,C,原理：认为每相的R、L和开关管的压降都相同，星行连接点的电压VDC/2,反电势过零点被偏置为VDC/2，相电压与VDC/2比较,回路构成：,BLDCM驱动原理-BEMF检测,Motor Speed Vm(=DCV PWM duty)通过控制 PWM DUTY 来控制 Motor 转速.,BLDCM驱动原理-速度控制,Block Diagram of Outdoor Unit Inverter Controller,INVERTER part,CONVERTER part,BLDCM在空调中的应用-Block Diagram,93%Typical(120度 通电方式)(Loss 7%),Ex.4KW input controller loss=4000W x 7%=280W,2%80W,2.5%100W,1.25%50W,1%40W,0.25%10W,Heatsink 4.75%=190W,heatsink,heatsink,heatsink,BLDCM在空调中的应用-Thermol Design,