锯齿波电流有效值(均方根).doc
锯齿波电流有效值:
22TDT2iRTKtdRdtKtdRdt,,,,,,,,,,,,,,rms12,,120TD
-----(式1)
IIIII,,;其中:是平均值,是交流电流; DCACPKDCAC
2,IACdII,,K,;; 1DCAC1TD,
D,12,IdII,,,AC2DCACK,,;; 2TD,,11,D,,
先计算式1中第一个积分:
TD222,,,,RKtKdtddt2,,1111,0
TD23,,Kt221,,,,RKdtdt111,,3,,0
2,,2III,,,4I2ACDCAC3322AC,,,,RTDTDIITD,,,,DCAC223TDTD,,
2,,4I222AC,,,,,,RTDIITDITDITDIITDITD222ACDCACDCACDCAC,,3,,
2,,,,4I222AC,,,,RIITDITD2,,,,ACACDC3,,,,
2,,I2AC,,RTDIDC,,3,,
再计算式1中第二个积分:
T222,,,,RKtKdtddt2,,2222,TD
T23,,Kt222,,,,RKdtdt222,,3,,TD
,,,1D,,2III,2ACDCAC2,,,,4I1,D1,D,,,,3322AC,,,,,,,,,RTDTDIITD1(1)(1),,DCAC,,2211TDD,,,,,,,,31TD,,,
,,,,
22,,42III(1,D)22ACACDC(1)(1)2,,,,,DDDIAC,,221,D(1),D,,31,D,,,,,,RTD(1),,22II(1),D22ACDC,,,,,,IDI(1)DCAC2,,1,D(1),D,,,,
22,,,,4(1)(1),,,DDD22,,,,,,,,RTDII(1)ACDC22,,(1),D,,31,D,,,,,,
22,,444363,,,,,DDDD22,,,RTDII(1)(),,ACDC231,D,,,,,,
2DD,,2122,,,RTDII(1)[()]AC2DC31,D,,
122(1)[],,,RTDIIACDC3
所以:
222,,,,II12222ACACiRT,,, + =; RTDII,,RTDI,RTI,,,(1)[]ACDCDCDCrms,,,,333,,,,
I22AC()iI,,RMSDC. 3