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書式設定,書式設定,第 2,第 3,第 4,第 5,*,使用变频器的电机控制技术,2013,年,6,月,29,日,中央空調事業部,上野佐千夫,电机控制的概要,压缩机的控制,傅立叶级数和应用例的介绍,矢量控制,、,电机参数的计算方法,1,电机控制,:,电机控制的概要,电机控制上所需的运动方程式,磁通和诱启电压的关系,3,相电机的转矩发生原理,转矩常数和诱启电压常数,极数和电机转矩,转矩脉动的影响和原因,齿槽转矩引起的转矩脉动,诱启电压失真引起的转矩脉动,电流失真引起的转矩脉动,10,诱启电压失真引起的转矩脉动的补偿,(1),11,诱启电压失真引起的转矩脉动的补偿,(2),12,速度反馈电路的增益最优化带来的转矩脉动补偿例,2,工作率,P,(power),P=d(W)/dt,w,转矩,Tr,(torque),Nm,位移,(,角度,),(angle),rad,or,角,速度,(angular velocity),rad/s,角加速度,(angular acceleration),ddt rad/s,2,力,F,(force),N=kg,m/sec,2,位移,(,距離,)s,(dispacement),m,速度,v,(velocity),m/sec,加速度,a,(acceleration),m/sec,2,工作,W,(work),W=F,s,J,P=d(F,s)/dt=F,d(s)/dt=,F,v,(,力,速度,),=(F,r),(,v,/r)=,Tr,v,(,转矩,角速度,),直线运动,回转运动,电机控制上所需要的运动方程式,M,F,&,Tr,r,速度,v,角转速,n,=2,n,重力加速度,g,質量,M:100kg,速度,v,:,2m/sec,半径,r,:,0.01m,P=Mg,v,=1009.812=1962W,Tr=F,r=Mg,r=100*9.81*0.01=9.81 Nm,=,v,/r=2/0.01=200 rad/sec,P=,v,Tr=9.81 200=1962 W,F=Mg,n,=/2=200/2=31.8 rps,转速,n,Tr=Fr=Mgr,角速度,v,=,v,/r,3,S,N,U,V,W,C,E=n,d()/dt,n,Eu,磁束,设,n,(t),=,sint,E,=n,=Ke,磁通和诱启电压,(E),的关系,永磁电机一回转,端子间发生诱启电压。,诱启电压和总交链磁通,(,磁通的大小,和匝数,n,的积,),与转速,(,),成比例变大,。,n,=,:,诱启电压常数,4,極,Motor,磁通,(t),10rps,(20Hz),20rps,(40Hz),诱启电压,E(t),20rps,(40Hz),10rps,(20Hz),4,長度,磁束密度,B,F=B,i,n,磁束,電流,I,電流,磁束,转矩,(,Torque),S,N,n,U,转矩,V,转矩,W,转矩,3,相合計转矩,相对,磁通,前进了,90,度,的,電流,外加到,1,相时的,转矩,各,3,相的转矩和,3,相合计转矩,Tr(,合計,)=3,i=1.5,rms,I,rms,=Kt,I,rms,Kt:,转矩常数,3,相,电机的转矩发生原理,转矩,n=,5,转矩常数,诱启电压常数,工作,P,用运动方程式和电气工学可表现,P,=,v,Tr=3,I,v,:角,转速,2N,Wf,:角,频率,f,=2f=P,o,f,N,:,转速,rps,N=2f/P,o,f,:,频率,Hz,f=N*P,o,/2,E,:,1,相,的诱启电压,(,有效值,),I,:,1,相,的电流,(,有效值,),:,磁通的大小,(,磁铁的磁通密度,B,磁,磁路横截面,S,),n,:,匝数,Po,:極数,B,:,磁铁的磁通密度,T,S,:,磁路的横截面,m,2,Tr=1.5,n,Po,B,S,I,Kt,:,转矩常数,匝数,n,極数,Po,磁铁的磁通密度,B,电机的磁路面积,S,N,N,S,S,N,S,N,N,N,S,S,S,4,極,转子,8,極,转子,E=n,d(),/,dt,=,n,=n,2f,=n2,N,P,o,/2,B,S,=n,P,o/2,B,S,2N,=0.5,n,Po,B,S,v,Ke,:,诱启电压常数,诱启电压常数,转矩常数相同性质,和下面的特性成比例。,6,N,:,10rps,磁束,(t),4,極,(20Hz),8,極,(40Hz),诱启电压,E(t),8,極,(40Hz),4,極,(20Hz),N,N,S,S,4,極,转子,N,S,N,N,N,S,S,S,8,極,转子,定子相同,仅转子的极数变更了时,极数和电机转矩,磁滞损耗,=,h,f,B,m,2,过电流损耗,=,e,(t,f,B,m,),2,B,m,:,磁通密度的最大值,(,T,),e,=k,(,k:,定数),f,:,频率,(,Hz,),:,铁心的材质决定的常数,铁损,=,磁滞损耗,+,过电流损耗,转速低的用途,(,风机,),是增加极数,转速高的用途,(,压缩机,),是把磁通密度,B,设大,7,转矩脉动发生因素,空间磁场抢走的齿槽转矩发生,诱启电压失真,电流波形失真,负载转矩的失真,羽,风叶的片数和形状、同心度不良、主轴的扭力振动,电机设计,电机设计,变频器设计,整机、风叶等结构设计,因素的主要原因,转矩脉动的影响和原因,转矩的一般式,Tr=J,dw/dt,dw,r,/dt=,Tm-Tl,J,+,Tmr+Tlr,J,通常的负载和,加速減速,振动,(,外,干扰,),发生,马达发生的振动转矩,负载发生的振动转矩,F=M,dv/dt,Tr,=,P/,r,(E,1,+E,n,),(I,1,+I,n,),r,=,=,E,1,I,1,+(E,n,I,n,),r,仕事,振动,(,外干扰),成分,8,7,齿槽转矩引起的转矩脉动,齿槽转矩是在电流为零的时候,由电机槽的空间谐波、磁铁磁分布的谐波发生的转矩的脉动,1,转发生的齿槽转矩的数量由槽和极数的最小公倍数决定,N,S,N,N,N,S,S,S,和多极化组合带来的低减,9,8,诱启电压失真引起的转矩脉动,诱启电压失真率引起的振动,誘起電圧波形,Yuukidennatuhakei,诱启电压,電流,(,失真率,0%),转矩,(U,相,),转矩,(,3,相合計,),转矩,(,V,相,),转矩,(,W,相,),诱启电压的谐波,10,9,电流失真引起的转矩脉动,120,矩形波控制变频器,180,正弦波控制变频器,電流波形,次成分,11,10,诱启电压失真引起的转矩脉动的补偿,(1),诱启电压失真率引起的振动,诱启电压的谐波,转矩,(U,相,),转矩,(,3,相合計,),转矩,(,V,相,),转矩,(,W,相,),Motor,電流,的谐波,12,诱启电压失真率引起的振动,转矩,(U,相,),转矩,(,3,相合計,),转矩,(,V,相,),转矩,(,W,相,),诱启电压的谐波,Motor,电流的谐波,11,诱启电压失真引起的转矩脉动的补偿,(2),13,诱启电压失真引起的转矩脉动的补偿例总结,14,12,速度反馈电路的增益(,Gain),最优化带来的转矩脉动补偿例,電流,反馈,回路,速度,反馈电路,KpS,:,速度环比例增益,KxS,:速度,环积分增益,Kp(x)I,:,電流,环增益,速度,环增益的最优,化,带来的外干扰抑制,速度修正強度,频率,(,转速,),15,16,电机控制,2,:,压缩机的控制,从莫利尔线图(焓差图)计算电机转矩,能量,焓,莫利尔线图,R718(,水,),的莫利尔线图,R410A,的莫利尔线图,压缩的功,制冷量,电机的转矩计算,(,理论值,),电机的转矩计算,(,实测值,),10,变频器的效果,11.,冷媒的特性,17,能量是什么,完成事物的气力和活力,。,是作为活动的源泉保持在体内的力。,是物体能进行物理性工作的能力,。,持有某种潜在的系统,可对外部进行活动的做功的量,。,能量,资源,。,位置能量,运动能量,电能量,热能量,化学能量,光能量,音能量,原子核能量,国际单位系统里,能量的单位是,J,其它,卡路里,cal,、,瓦特时,Wh,电子伏特,eV,英国热量,Btu,等,18,焓,(enthalpy),焓:物质的发热、吸热的动作,与对外部的做功的量有关的值,向外部发热,焓下降,从外部吸热,焓上升,向外部做功,焓下降,从外部接收功,焓上升,H=U+PV,J,H:,焓,U,:,内部能量,P,:圧力,V,:,体积,19,比容,曲線,等比,熵曲线,等温曲線,等干燥度曲线,比焓的基准点,0,饱和液线,200,kJ/kg,饱和曲线,干燥饱和蒸气线,90%,80%,20%,10%,莫利尔线图,20,等温曲線,Mollier Diagram,h,(,比,焓,kJ/kg,),莫利尔线图,21,等比容曲线,Mollier Diagram,(,比,焓,kJ/kg,),莫利尔线图,22,等比熵曲线,Mollier Diagram,(,比,焓,kJ/kg,),莫利尔线图,23,饱和液线,、,干燥饱和蒸气线,Mollier Diagram,莫利尔线图,24,200,kJ/kg,2875.8,kJ/kg,619.7,kJ/kg,h,=2875.8-619.7=,2256.1,kJ/kg,=539,cal/g,h,=619.7-200=,419.7,kJ/kg,=100,cal/g,R718(,水,),的莫利尔线图,3074.9,kJ/kg,h”,=3074.9-2875.8,=,199.2,kJ/kg,=47.6,cal/g,25,R410A,的莫利尔线图,A,B,C,D,隔热压缩,熵一定,凝縮,圧力一定,蒸発,圧力一定,膨胀,焓一定,26,A,点,T:18.3,P:0.9958MPa,h:437.41hJ/kg,V:0.028567m3/kg,S:1.8463kJ/(kg,),点,T:7.2,干燥饱和蒸气曲线,Mollier Diagram,R410A,的莫利尔线图,27,点,T:54.4,P,:,.3505MPa,B,点,T,:,87.153,P,:,3.3505MPa,h,:,473.102kJ/kg,S:1.8463kJ/(kg,),乾飽和蒸気曲線,Mollier Diagram,R410A,的莫利尔线图,28,C,点,p,:,3.3505MPa,T,:,46.1,h:283.539kJ/kg,点,T,:,46.1,h,:,283.539kJ/kg,飽和液曲線,Mollier Diagram,29,D,点,p:0.9958MPa,h:283.539kJ/kg,Mollier Diagram,R410A,的莫利尔线图,30,Mollier Diagram,5.R410A,ARI,条件,的归纳,A,B,C,D,焓,比容,熵,31,6.,圧縮,的功,ARI,条件,的时候,A,B,C,D,h,AB,A,点,和,B,点,的比焓,差:,h,AB,冷媒,1kg,的功,(J),473.092-437.402=,35.69kJ/kg,A,点,的冷媒的比容的,逆数,1/0.028565=35.008kg/m,3,冷媒,1m,3,的质量,kg,压缩质量,1m,3,的,冷媒,的功,=,(473.092-437.402)/0.028565,=1.2494MJ/m,3,或者,1.2494 J/cm,3,压缩体积,M,、,转速,N,时候的功,(,瓦特,),例:,30.6cm,3,、,60rps,1.2494*30.6*60=,2293W,功系数,焓,熵,比容,32,7.,制冷量,ARI,条件,的时候,A,B,C,D,h,AB,A,点,和,D,点,的比焓,差:,h,AD,冷媒,1kg,的制冷能量,(J),437.402-283.539=,153.863,kJ/kg,A,点,的,冷媒,的比容的,逆数,1/0.028565=35.008kg/m,3,冷媒,1m,3,的质量,质,量,1m3,的,制冷,能量,(J),=,(437.402-283.539)/0.028565,=5.3864MJ/m,3,或者是,5.3864 J/cm,3,圧縮体積,M,、回転数,N,的时候的,制冷,瓦特,例:,30.6cm,3,、,60rps,5.3864*30.6*60=,9889.5W,制冷,系,数,焓,熵,比容,33,8.,电机的转矩计算,ARI,条件,的时候,A,B,C,D,h,AB,圧縮体積,M,、回転数,N,的时候的功,(,瓦特,),例:,30.6cm,3,、,60rps,1.2494*30.6*60=,2293W,电机的功,(,瓦特,)=,角转速,转速,(T),2293/(2*60)=,6.085Nm,(hB-hA)/v*M*N=2*N*Torque,hA,hB:A,点、,B,点,的比焓,V,:,A,点,的比容,M,:圧縮機,的压缩体积,N,;圧縮機,的转速,Torque,(hB-hA)*M,v*2*,(473.092-437.402)*30.6/1000,(0.028565*2*),=6.085 Nm,焓,熵,比容,34,从压缩机的特性试验来,计算电机转矩的方法,测量条件,转速、冷凝温度、蒸发温度、过冷度、过热度,测量项目,制冷瓦特,、,压缩机输入瓦特,、,电机电流,、,电机电阻,电机的转矩计算,实际值,35,55.4,、,7.2,13.70Arms,Evaporating,Temperature,电机的转矩计算,实际值,36,55.4,、,7.2,3074W,55.4,、,7.2,9705.8W,Evaporating,Temperature,Evaporating,Temperature,电机的转矩计算,实际值,37,60rps,、,CondTemp54.4,、,EvapoTemp7.2,压缩机动 特性数据,电机损失,W,loss=,銅損,+,鉄損,3 RaIa,2,1.5=,223.7,W,电机功,Wm=,电机输入,电机损失,=,3074.0,-223.7=,2850.3,W,电机转矩,Tm=,电机的功,/,角转速,=Wm/(2N)=2850.3/(260)=,7.561,Nm,电机的转矩计算,实际值,38,压缩机的特性结果,制冷効率,C,和从实际的制冷瓦特和冷冻系统计算出来的理论制冷瓦特的比,機械効率,C,和从实际的电机转矩和冷冻系统计算出来的理论转矩的比,电机效率,M,和从实际的压缩机输入功率和冷冻系统计算出来的功功率的比,圧縮機,综合,効率,total,和实际的制冷功率与实际的压缩机输入功率的比,压缩机综合效率,total,=,制冷効率,C,機械効率,C,电机,効率,M,能量消费效率,COP,total,实际的制冷功率,实际的压缩机输入功率,理,论,COP,从冷冻系统计算出来的、理论制冷功率,/,理论功功率,COP,total,=,理論,COP,圧縮機総合効率,total,电机的转矩计算,实际值,39,效率计算结果,电机输入,电机电流,电机电阻,电机损失,电机的功,测量的,电机效率,实际转矩,理论转矩,电机的转矩计算,实际值,40,98.1%,80.5%,92.7%,73.2%,99.4%,78.6%,95.2%,74.4%,91.8%,81.2%,68.9%,92.3%,电机的转矩计算,实际值,41,28.7rps,53.3rps,90rps,10,变频器的效果,11.8rps,让制冷量下降时,使用变频器让频率下降,效率(,COP,)会明显上升。,42,制冷量,100%,75%,50%,25%,制冷量,25%,50%,75%,100%,制冷量,100%,75%,50%,25%,制冷量,25%,50%,75%,100%,10,变频器的效果,43,凝縮温度,蒸発温度,過熱度,過冷却度,莫利尔线图,温度和冷冻系统的关系,变频的效果,冷媒的特性,44,44.615,kJ/kg,149.902,kJ/kg,158.254,kJ/kg,25.43,kJ/kg,冷凝,温度,50,過冷却度,5,蒸発温度,15,10,5,0,-5,比容,0.025,m,3,/kg,比,容,0.0415,m,3,/kg,过热度,10,蒸发温度和功,制冷系数的关系,45,44.615,kJ/kg,149.902,kJ/kg,158.254,kJ/kg,25.43,kJ/kg,冷凝,温度,50,蒸発温度,15,比,容,0.0225,m,3,/kg,比体積,0.0415,m,3,/kg,蒸発温度,-5,圧力,3.0333MPa,圧力,1.2489MPa,圧力,0.6803MPa,蒸发温度,15,的功系数,25.43/0.0225/1000=,1.130,J/cm,3,蒸发温度,-5,的功系数,44.615/0.0415/1000=,1.074,J/cm,3,蒸发温度,15,的制冷系数,158.254/0.0225/1000=,7.033,J/cm,3,蒸发温度,-5,的制冷系数,149.902/0.0415/1000=,3.608,J/cm,3,能量变化,功系数,:,1.130/1.074=,1.05,倍,制冷,系数,:,7.033/3.608=,1.95,倍,比,焓的变化,功,:,25.43/44.615=,0.57,倍,制冷量:,158.254/149.902=,1.06,倍,圧力:,1.2478/0.06803=,1.84,倍,圧力差:,(3.0333-1.2489)/(3.0333-0.6803),=0.76,倍,絶対温度,:,(273.15,+15,)/(273.15,-5,),=1.07,倍,温度差:,(50+5)/(50-15)=1.57,倍,比,容,:,0.0225/0.0415=,0.54,倍,逆数,0.0415/0.0225=,1.84,倍,蒸发温度和功,制冷系数的关系,46,对,蒸発温度,的温度系数,:,0.22%/,对冷凝,温度,的温度系数,:,2.06%/,蒸发温度和功系数的关系,47,对蒸发温度的温度系数,:,3.37,%/,对冷凝温度的温度系数,:,2.06%/,蒸发温度和功系数的关系,48,冷凝温度和功制冷系数的关系,過冷却度,5,凝縮温度,62,60,55,50,45,40,35,蒸発温度,5,過熱度,10,hA:,435.505,kJ/kg,v:,0.0304,m,3,/kg,hB:,459.404,kJ/kg,hB:,476.794,kJ/kg,hD:,305.077,kJ/kg,hD:,250.670,kJ/kg,49,冷凝,温度,60,圧力,3.7908,MPa,冷凝,温度,35,圧力,2.1214,MPa,蒸発温度,5,圧力,0.932MPa,184.835,kJ/kg,130.428,kJ/kg,23.899,kJ/kg,41.289,kJ/kg,比体積,0.030362,m,3,/kg,冷凝,温度,60,的功系数,41.289/0.03036/1000=,1.360,J/cm,3,冷凝,温度,35,的功系数,23.899/0.03036/1000=,0.787,J/cm,3,冷凝,温度,60,制冷係数,130.428/0.03036/1000=,4.296,J/cm,3,冷凝,温度,35,制冷係数,184.835/0.03036/1000=,6.088,J/cm,3,能量变化,功系数,:,1.360/0.787=,1.73,倍,制冷,系数,:,4.296/6.088,=,0.706,倍,比,焓的变化,功,:,41.289/23.899=,1.73,倍,制冷量:,130.428/184.835=,0.706,倍,比,容,:,1,倍,圧力:,3.7908/2.1214=,1.79,倍,圧力差:,(3.7908-0.932)/(2.1214-0.932),=2.40,倍,絶対温度,:,(273.15+,60,)/(273.15,+,35,),=1.08,倍,温度差:,(60-5)/(35-5)=1.83,倍,冷凝温度和功,制冷系数的关系,50,对冷凝温度的温度系数,:,2.06,%/,对蒸发,温度,的温度系数,:,0.22%/,冷凝温度和功系数的关系,51,对冷凝温度的温度系数,:,-1.43%/,对冷凝温度的温度系数,:,3.37%/,冷凝温度和制冷系数的关系,52,冷凝,温度,50,蒸発温度,5,过冷却度,5,h,A:,431.065,kJ/kg,v:0.02954,m3/kg,h,A:,435.505,kJ/kg,v:0.03036,m3/kg,h,A:,439.952,kJ/kg,v:0.03117,m3/kg,h,A:,444.409,kJ/kg,v:0.03197,m3/kg,h,B:,464.611,kJ/kg,h,B:,480.97,kJ/kg,h,B:,470.077,kJ/kg,h,B:,475.528,kJ/kg,h,D:,281.091,kJ/kg,过热度和功,制冷系数的关系,53,过热度和功,制冷,系数的关系,圧力:,1,倍,圧力差:,1,倍,絶対温度,:,(273.15+,25,)/(273.15,+,10,),=1.05,倍,温度差:,(90.227-25)/(76.153-10),=0.99,倍,h,B:,480.97,kJ/kg,T:90.227,h,B:,464.611,kJ/kg,T:76.153,冷凝温度,50,蒸発温度,5,h,A:,444.409,kJ/kg,v:0.03197,m3/kg,T:25,h,D:,281.091,kJ/kg,h,A:,431.065,kJ/kg,v:0.02954,m3/kg,T:10,能量变化,功系数,:,1.144/1.136,=,1.01,倍,制冷,系,数:,4.296/6.088,=,1.01,倍,比,焓的变化,功,:,36.561/33.546=,1.09,倍,制冷量:,163.32/149.97=,1.09,倍,比,容,:,0.03197/0.02954,=1.08,倍,54,过热度和功系数的关系,对过热度的温度系数,:,0.05%/,对冷凝温度的温度系数,:,2.06%/,55,过热度和制冷系数的关系,对过热度的温度系数,:,0.04%/,对冷凝温度的温度系数,:,-1.43%/,56,过冷却度和功,制冷,系数的关系,h,D:,250.067,kJ/kg,h,D,260.277,kJ/kg,h,D:,270.376,kJ/kg,h,D:,281.091,kJ/kg,冷凝温度,50,蒸発温度,5,過冷却度,5,過冷却度,10,過冷却度,15,過冷却度,20,h,A:,435.505,kJ/kg,v:0.0304,m3/kg,h,B:,470.077,kJ/kg,57,過冷却度,和功,制冷,系,数,的关系,h,D:,250.067,kJ/kg,h,D,260.277,kJ/kg,h,D:,270.376,kJ/kg,h,D:,281.091,kJ/kg,凝縮温度,50,蒸発温度,5,過冷却度,5,10,15,20,h,A:,435.505,kJ/kg,v:0.0304,m3/kg,h,B:,470.077,kJ/kg,功系数不受过冷却度影响,制冷系数受过冷却度影响很大,58,对过冷却度的温度系数,:,1.31%/,对蒸发温度的温度系数,:,3.37%/,過冷却度,和,制冷,系数的关系,59,对过冷却度的温度系数,:,1.31%/,对冷凝温度的温度系数,:,-1.43%/,过冷却度和制冷系数的关系,60,温度和冷冻系统的归纳,凝縮温度,蒸発温度,過熱度,過冷却度,制冷,系,数:,-1.43,%/,功系数,:,0.22,%/,制冷,系,数:,3.37,%/,功系数,:,2.06,%/,功系,数:,0.04,%/,制冷,系,数:,0.03%/,制冷,系,数:,1.31,%/,功系,数:,0,%/,61,90,rps,60,rps,30,rps,莫利尔线图,变频的效果,62,莫利尔线图,冷媒的特性,R134a,R22,R410,R600a,R717,R718,R744,63,R410A,臭氧层破坏系数 零,地球,温室化系数 高,功系数,:,1.249J/cm3,制冷,系,数:,5.386J/cm3,COP,:,4.3,圧力:,3.4MPa,ODP:0,GWP:2090,冷媒的特性,64,R134a,冷媒,的,特性,功系数,:,0.4991J/cm3,制冷,系数,:,2.4933J/cm3,COP,:,5.0,圧力:,1.4MPa,ODP:0,GWP:1430,COP,高,地球温暖化係数 高,制冷,系,数,小,65,R22,功系数,:,0.819J/cm3,制冷,系数,:,3.952J/cm3,COP,:,4.8,圧力:,2.1MPa,ODP:0.055,GWP:1810,冷媒,的特性,臭氧层破坏系数,高,地球温暖化,系,数 高,66,R600a:CH(CH,3,),3,Iso-Butane,仕事,系,数:,0.276J/cm3,制冷,系,数:,1.406J/cm3,COP,:,5.1,圧力:,0.77MPa,ODP:0,GWP:3,COP,高,有爆发的危险性,制冷,系数小,冷媒,的,特性,67,R717:NH,3,Ammonia,仕事,系,数:,0.919J/cm3,制冷,系,数:,4.553J/cm3,COP,:,5.0,圧力:,2.3MPa,ODP:0,GWP:0,对环境好,COP,高,毒性気体,冷媒,的,特性,68,R718:H,2,O,水,仕事,系,数:,3.9,m,J/cm3,制冷,系,数:,17.7,m,J/cm3,COP,:,4.5,圧力:,0.017MPa,ODP,:,0,GWP,:,0,最安全的冷媒,压力太低了,(0.02MPa),需要,圧縮体積,or,转数,300,倍,冷媒,的,特性,69,R744:CO,2,二氧化碳,仕事,系数,:,3.6J/cm3,制冷,系,数:,8.6J/cm3,COP,:,2.4,圧力:,9MPa,ODP:0,GWP:1,安全,的冷媒,制冷,系,数,大,圧力 高,(9MPa),冷媒,的特性,70,冷媒,的,比較表,冷媒,的特性,71,72,傅里叶级数及应用例介绍,傅里叶级数,傅里叶级数的应用例介绍,73,y(t),=,b,0,+,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,b,0,=,1,T,0,T,y(t),d,t,b,n,=,2,T,0,T,y(t),cos,n,t,a,n,=,2,T,0,T,y(t),sin,n,t,傅里叶级数,所有的,周期函数,都可用,sin,和,cos,的谐波的和来表现。,周期函数,是指在变量,t,的函数,y(t),上满足下式的函数。,y(t),=,y(,t,+n,T,),T,是周期,,n,是任意的整数,n,=1,:基波,n2,:,谐波,74,y(t)=A1,sin(,t,+)=,A1,(sin,t,cos+cos,t,sin),a,1,=,2,T,0,T,y(t),sin,1,t,=,2,T,0,T,(,A1,sin,t,cos,+A1,costsin),sin,t,d,t,=,2,T,0,T,A1,cos,sin,2,t,dt,=,2,T,0,T,A1,cos,d,t,1-cos(2,t,),2,=,A1,cos,A1,sin,sin,t,cos,t,d,t,2,T,0,T,+,A1,cos,=,2,T,0,T,d,t,2,(1-cos(2,t,),+,2,T,0,T,A1,sin,d,t,sin(2,t,),2,A1,sin,+,2,T,0,T,d,t,2,(sin(2,t,),0,T,=,A1,cos,sin,t,+,A1,sin,cos,t,公式证明,理論,0,75,y(t)=A1,sin(,t,+)=,A1,(sin,t,cos+cos,t,sin),b,1,=,2,T,0,T,y(t),sin,1,t,=,2,T,0,T,(,A1,sin,t,cos,+A1,costsin),cos,t,d,t,=,2,T,0,T,A1,sin,cos,2,t,dt,=,2,T,0,T,A1,sin,d,t,1+cos(2,t,),2,=,A1,sin,A1,cos,sin,t,cos,t,d,t,2,T,0,T,+,A1,sin,=,2,T,0,T,d,t,2,(1+cos(2,t,),+,2,T,0,T,A1,cos,d,t,sin(2,t,),2,A1,cos,+,2,T,0,T,d,t,2,(sin(2,t,),=,A1,cos,sin,t,+,A1,sin,cos,t,公式证明,理論,0,0,T,76,对称函数,y,(,t,+,)=-,y,(,t,),T,2,T,2,T,0,奇函数,y,(,t,)=-,y,(-,t,),T,2,T,0,偶函数,y,(,t,)=,y,(-,t,),T,2,T,0,y(t),=,b,0,+(,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,理論,77,y,(,t,+,)=-,y,(,t,),T,2,T,2,T,0,y,(,t,)=-,y,(-,t,),T,2,T,0,y,(,t,)=,y,(-,t,),T,2,T,0,y(t),=,b,0,+(,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,b,0,=0,a,n,b,n,n,奇数,b,0,=0,b,n,=0,a,n,=0,a,n,=,4,T,0,T/2,y(t),sin,n,t,d,t,b,n,=,4,T,0,T/2,y(t),cos,n,t,d,t,a,n,=,4,T,0,T/2,y(t),sin,n,t,d,t,b,n,=,4,T,0,T/2,y(t),cos,n,t,d,t,b,0,=,2,T,0,T/2,y(t),d,t,理論,对称函数,奇函数,偶函数,78,1,次,sin+2,次,sin,1,次,sin+2,次,cos,1,次,sin+3,次,sin,1,次,sin+3,次,cos,对,称,函数,对,称,函数,奇函数,奇,函数,非对称函数,总电流,基波电流,2,次,谐波电流,理論,79,矩形波,y(t),=,b,0,+(,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,=,a,n,sin(,n,t),n,=2m+1,a,n,=,4,T,0,T/2,y(t),sin,n,t,d,t,=,4,T,0,T/2,A,sin,n,t,d,t,=,4A,n,y(t),=,(sint+,sin3t+sin5t+sin7t+sin9t,),4A,1,3,1,5,1,7,1,9,对称函数 且是,奇函数,因此只存在,An,的项,,n,是奇数,0,T,2,T,A,1.273A,理論,80,n,:1,3,n,:1,9,n,:1,41,n,:1,99,理論,谐波次数和矩形波波形,81,0,T,A,T,2,16.83,度,理論,矩形波的谐波分析,82,梯形波,对称函数,且是,奇函数,因此只存在,An,的项,,n,是奇数,0,T,2,T,A,y(t),=,b,0,+(,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,=,a,n,sin(,n,t),n,=2m+1,=,4Asin(2,n,+1),(2,n,+1),2,A,2n+1,=,4,T,0,T/2,y(t),sin,n,t,d,t,=,8,T,0,sin(2,n+1),t,d,t,A,t,+,8,T,T/4,A,sin(2,n+1),t,d,t,y(t),=,(,sin,sint,+,sin3,sin3t,+,sin3,sin5t,+,),4A,1,3,2,1,5,2,理論,83,0,T,2,T,A,理論,梯形波的谐波分析,84,三,角,波,y(t),=,b,0,+(,b,n,cos(,n,t)+,a,n,sin(,n,t),n,=1,=,a,n,sin(,n,t),n,=2m+1,a,n,=,4,T,0,T/2,y(t),sin,n,t,d,t,=,4,T,0,T/2,A,sin,n,t,d,t,=,8A,2,(2n+1),2,y(t),=,(sint-,sin3t+sin5t-sin7t+sin9t,),8A,2,1,3,2,1,5,2,1,7,2,1,9,2,对称函数,且是,奇函数,因此只存在,An,的项,,n,是奇数,0,T,2,T,A,(-1),n,0.811A,理論,85,n,:1,3,n,:1,9,n,:1,41,n,:1,99,理論,谐波次数和三角波波形,86,特殊三角波的谐波分析,理論,三角波的电流谐波成分,87,含,3,次谐波的电流波形,仅基波波形的功率,基波电流,3,次,谐波电流,总电流,W,W,W,电流谐波和功率,(W,),功率只由电压和基波电流决定(,谐波电流和功率无关,),电压,电压,电压,电压,W=,v(t),i(t),dt,0,T,基波电流,3,次,谐波电流,总电流,理論,88,Sin,电流,Cos,电流,总电流,Cos,电流,总电流,W,W,W,电流功率因数和功率(,W),功率由和电压同相的电流和电压的积决定,W=,v(t),i(t),dt,0,T,电压,电压,电压,电压,Sin,电流,理論,89,傅里叶级数的应用例介绍,电机的诱启电压分析,:,振动噪音对策,PFC,电源谐波分析,90,测量波形,谐波分析,2,27,次,谐波相加,(2,27,次,谐波,)3,相加,応用,750W Motor 8,极诱启电压分析,91,1,27,次谐波相加,5,次,10,谐波相加,7,次,10,谐波相加,11,次,10,谐波相加,応用,750W Motor 8,极诱启电压分析,92,测量波形,2,27,次,谐波相加,谐波分析,(2,27,次,谐波,)3,相加,応用,170W Motor 10,极诱启电压分析,93,1,27,次,谐波相加,11,次,10,谐波相加,4,次,10,谐波相加,6,次,10,谐波相加,応用,170W 10,极,Motor,诱启电压分析,94,8,极,vs 10,极,输出,W,Torque,输出,W,Torque,Torque,扩大,8,极,750W,10,极,170W,95,圧縮機,Motor,誘起電圧,96,圧縮機,Motor,誘起電圧,97,PFC(,功率因数校正,),的思维方式,最大限度提高电源效率,=,最大限度地提高了功率因数,功率因数的定义,功率因数,=,电压和电流的积,(,视在功率,:,apparent,power),实际消耗的功率,(,有,功功率,:,active power),电流的功率因数,=,和电压同相的基波电流的有效值,全部次数的有效值电流的平方和的平方根,和电压同相的基波电流有效值,基波电流有效值,基波电流有效值,=,=,基波电流的功率因数,电流失真的功率因数,全部次数的有效值电流的平方和的平方根,IEC61000-3-2/12,有规定,现在没有规定,1,h,応用,PFC,的谐波分析,98,谐波电流,:,2.74,Apeak,电源电流,:,6.67,Apeak,谐波电流,:,0.65,Apeak,电源电流,:,5.44,Apeak,谐波电流,:,6.81,Apeak,电源电流,:,9.43,Apeak,90,三角波,60,三角波,30,三角波,90,三角波的功率,220,V,rms,3.82,A,rms,=,841,W,60,三角波的功率,220,V,rms,4.30,A,rms,=,946,W,30,三角波的功率,220,V,rms,4.61,A,rms,=,1014,W,5.40,A,peak,応用,三角波电流的谐波(同相),99,谐波电压,:,2.74,Apeak,电源电流,:,6.67,Apeak,谐波电流,:,2.74,Apeak,电源电流,:,6.67,Apeak,60,三角波,(,和电压同相,),60,三角波(比电压滞后,30,),和电压同相的三角波电流的功率,220,V,rms,4.30,A,rms,=,946,W,比电压滞后,30,三有波电流的功率,220,V,rms,3.72,A,rms,=,819,W,応用,三角波电流的谐波,(,滞后,30,度,),100,Vdc,L,C,負荷,I,
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