LLC计算书作者:汪永洪一、输入规格Vin_min370V:=Vin_nom400V:=Vin_max420V:=Vo12V:=Io20A:=η92%:=j1-:=fo100KHz:=二、变压器计算(独立漏感)1、变压器匝比Vf0.2V:=nVin_nom2VoVf+()×16.393=:=n_fact17:=Vin_o2n_fact×VoVf+()×414.8V=:=对应谐振时的输入电压所以前级PFC调整额定输出电压为414.8V2、电压增益Gmin2n_fact×VoVf+()×Vin_max0.988=:=Gmax2n_fact×VoVf+()×Vin_min1.121=:=3、等效负载PoVoIo×240W=:=Rac8n_fact2×π2Vo2Po×140.553Ω=:=4、谐振网络计算对最大增益留15%的裕量Gpk1.15Gmax×1.289=:=m05:=Q00.5:=Cr12π×Q0×fo×Rac×22.647nF×=:=Lr12π×fo×()2Cr×111.848μH×=:=------------------------------------------------------Cr_fact22nF:=Lr_fact12π×fo×()2Cr_fact×115.138μH×=:=Q0_fact2π×fo×Lr_fact×Rac0.515=:=Lpm0Lr_fact×575.689μH×=:=fp12π×LpCr_fact××44.721KHz×=:=ωfs()2π×fs×:=ωo2π×fo×:=ωp2π×fp×:=计算并校正Cr,Lr,QG0ω()ω2ωo2m01-()×ω2ωp21-æççèö÷÷øjωωo×ω2ωo21-æççèö÷÷ø×m01-()×Q0_fact×+:=----------------------------------------------------m16:=Lp1m1Lr_fact×690.826μH×=:=fp112π×Lp1Cr_fact××40.825KHz×=:=ωp12π×fp1×:=G1ω()ω2ωo2m11-()×ω2ωp121-æççèö÷÷øjωωo×ω2ωo21-æççèö÷÷ø×m11-()×Q0×+:=变m值----------------------------------------------------Q20.4:=Cr212π×Q2×fo×Rac×28.309nF×=:=Lr212π×fo×()2Cr2×89.479μH×=:=Lp2m0Lr2×447.393μH×=:=fp212π×Lp2Cr2××44.721KHz×=:=ωp22π×fp2×:=G2ω()ω2ωo2m01-()×ω2ωp221-æççèö÷÷øjωωo×ω2ωo21-æççèö÷÷ø×m01-()×Q2×+:=变Q值m36:=Q30.7:=Cr312π×Q3×fo×Rac×16.176nF×=:=Lr312π×fo×()2Cr3×156.588μH×=:=Lp3m3Lr3×939.526μH×=:=fp312π×Lp3Cr3××40.825KHz×=:=ωp32π×fp3×:=变Q,m值G3ω()ω2ωo2m31-()×ω2ωp321-æççèö÷÷øjωωo×ω2ωo21-æççèö÷÷ø×m31-()×Q3×+:=----------------------------------------------------4104´6104´8104´1105´1.2105´1.4105´1.6105´1.8105´0.40.5750.750.9251.11.2751.451.6251.80.9881.121G02π×fs×()G12π×fs×()G22π×fs×()G32π×fs×()103KHz80KHzfs最终选择m=5,Q=0.5fs0100KHz:=G02π×fs0×()1=fsmin80KHz:=G02π×fsmin×()1.124=最小开关频率,在最大增益处fsmax103KHz:=G02π×fsmax×()0.985=最大开关频率,在最小增益处从上图可知,对于m=5,Q=0.5,频率变化范围和参数取值可行5、核算ImIp先假定:MOS输出电容谐振腔电容死区时间Coss200pF:=Cstray100pF:=Td0.3μs:=ImVin_max2Lp14fsmax××0.885A=:=IpVin_maxTd2Coss×Cstray+()×0.7A=:=6、设计变压器fsmin80KHz×=ΔB0.35T:=Icr_rms1ηπIo×22×n_fact×æçèö÷ø2n_factVoVf+()×42×fo×LpLr-()×éêëùúû2+×1.66A=:=谐振腔电流有效值Io_rmsπIo×22×12×11.107A=:=副边线圈有效值J5Amm2:=Sp_wireIcr_rmsJ0.332mm2×=:=Ss_wireIo_rmsJ2.221mm2×=:=Rp_wireSp_wireπ0.325mm×=:=Rs_wireSs_wireπ0.841mm×=:=Dp_wire2Rp_wire×0.65mm×=:=Ds_wire2Rs_wire×1.682mm×=:=Dp_wire_fact0.15mm:=Ds_wire_fact0.2mm:=npSp_wireπDp_wire_fact2æçèö÷ø2×18.787=:=nsSs_wireπDs_wire_fact2æçèö÷ø2×70.711=:=先给定Ae80mm2:=Np_minn_factVoVf+()×2fsmin×ΔB×Ae×46.295=:=选择Ns使得NpNp_minNs3:=NpNsn_fact×51=:=窗口面积:辅助线圈和窗口并饶因素,窗口系数设置为0.3Kw0.3:=AwNpSp_wire×2NsSs_wire×+Kw100.869mm2×=:=所需APAeAw×0.807cm4×=:=-----------------------------------------------------选择PQ2625Ae1118mm2:=Aw184.5mm2:=AP1AeAw×0.807cm4×=:=Np_min1n_factVoVf+()×2fsmin×ΔB×Ae1×31.386=:=选择Ns使得Np1Np_min1Ns12:=Np1Ns1n_fact×34=:=此时填充系数Kw1Np1Sp_wire×2Ns1Ss_wire×+Aw10.239=:=选择PC44材质AL15.25μHN2:=LAL1Np12×N2×6.069103´μH×=:=而LmLpLr_fact-460.551μH×=:=磁芯感值足够,需要磨气隙三、漏感变压器选择Lr_fact115.138μH×=Iocp1.2Icr_rms×2×2.817A=:=选择RM10PC40材质Ae298mm2:=Aw269mm2:=AL236.3μHN2:=N_LrLr_factAL21.781N=:=N_Lr_fact50:=S_Lr_wireSp_wire0.332mm2×=:=Aw2_factN_Lr_factS_Lr_wire×16.6mm2×=:=V_Lr_pkVin_max2Iocp2×π×fo×Lr_fact×+413.798V=:=V_Lr_rmsV_Lr_pk2292.6V=:=ΔB_LrV_Lr_rms2fo×N_Lr_fact×Ae2×0.299T×=:=经验证RM10PC40OK四、谐振电容选择Vcr_pkVin_max2Iocp12π×fo×Cr_fact××+413.798V=:=实际上等于V_Lr_pk选择低ESR薄膜电容630V