BLDC原理与驱动.ppt

,bldcmotor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,categoryofbldcmotor,#note1.pmsm:permanentmagnetsynchronousmotor2.bldc:brushlessdc3.blac:brushlessac4.srm:switchedreluctancemotor5.synrm:synchronousreluctancemotor,motor,acmotor,dcmotor,inductionmotor,synchronousmotor,universalmotor,pmmotor,singlephasethreephase,pmsm(bldc,blac)srmsynrm,rotate,linear,categoryofdcmotor,innerrotortype,outerrotortype,rotor,stator,magnet,shaft,coil,structureofbldcmotor1,structureofbldcmotor1,structureofbldcmotor2,winding绕制,structureofbldcmotor2,structureofbldcmotor3,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),structureofbldcmotor3,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,easytoimplement-backemf(openphasevoltages)-lowresolutionofrotorposition:60deg,complextoimplement-estimator(voltagesl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,motorspeedvm(=dcvpwmduty)通过控制pwmduty来控制motor转速.,bldcm驱动原理-速度控制,blockdiagramofoutdoorunitinvertercontroller,inverterpart,converterpart,bldcm在空调中的应用-blockdiagram,93%typical(120度通电方式)(loss7%),ex.4kwinputcontrollerloss=4000wx7%=280w,2%80w,2.5%100w,1.25%50w,1%40w,0.25