Power factor correction
in [Design]
|
From: JosephKK on 3 Jan 2010 14:51 On Tue, 29 Dec 2009 13:44:36 GMT, Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >On a sunny day (Tue, 29 Dec 2009 07:17:31 -0600) it happened "Tim Williams" ><tmoranwms(a)charter.net> wrote in <Yhn_m.18015$wC3.5829(a)newsfe07.iad>: > >>PFC is a flyback thing. But flybacks suck over 100W, where forward looks >>better. But forward sucks over wide duty cycle ranges. What do they do, >>just bigger flybacks? Nothing at all? >> >>Tim >> >>-- >>Deep Friar: a very philosophical monk. >>Website: http://webpages.charter.net/dawill/tmoranwms > >For much higher power 3 phase rectifiers are used. >That leaves only a small ripple. >I am not sure if you need PFC in such a case. I am playing around with modeling 3-phase rectifiers. I think PFC would be a real good thing for 3-phase rectifiers. May be more than a tad interesting to implement though. I am getting some interesting results. I would really like to build some and measure them. Version 4 SHEET 1 880 680 WIRE 16 -368 -112 -368 WIRE 112 -368 16 -368 WIRE 304 -368 112 -368 WIRE 336 -368 304 -368 WIRE 544 -368 336 -368 WIRE -112 -288 -112 -368 WIRE 16 -288 16 -368 WIRE 112 -288 112 -368 WIRE 336 -192 336 -368 WIRE -384 -176 -768 -176 WIRE -768 -144 -768 -176 WIRE -384 -144 -384 -176 WIRE -192 -144 -288 -144 WIRE -112 -144 -112 -224 WIRE -112 -144 -192 -144 WIRE -768 -64 -832 -64 WIRE -384 -64 -480 -64 WIRE -192 -64 -288 -64 WIRE -384 0 -768 0 WIRE -768 32 -768 0 WIRE -384 32 -384 0 WIRE -144 32 -288 32 WIRE 16 32 16 -224 WIRE 16 32 -144 32 WIRE 544 32 544 -368 WIRE -192 64 -192 -64 WIRE 336 64 336 -128 WIRE 336 64 -192 64 WIRE 352 64 336 64 WIRE -832 112 -832 -64 WIRE -768 112 -832 112 WIRE -480 112 -480 -64 WIRE -384 112 -480 112 WIRE -192 112 -192 64 WIRE -192 112 -288 112 WIRE -384 176 -768 176 WIRE -768 192 -768 176 WIRE -384 208 -384 176 WIRE -144 208 -288 208 WIRE 112 208 112 -224 WIRE 112 208 -144 208 WIRE 352 240 352 64 WIRE -240 288 -288 288 WIRE -192 288 -192 112 WIRE -192 288 -240 288 WIRE -832 320 -832 112 WIRE -768 320 -768 272 WIRE -768 320 -832 320 WIRE -736 320 -768 320 WIRE -480 320 -480 112 WIRE -480 320 -736 320 WIRE -384 320 -384 288 WIRE -384 320 -480 320 WIRE -192 368 -192 288 WIRE -112 368 -112 -144 WIRE 16 368 16 32 WIRE 112 368 112 208 WIRE -736 528 -736 320 WIRE -560 528 -736 528 WIRE -240 528 -240 288 WIRE -240 528 -480 528 WIRE -112 528 -112 432 WIRE 16 528 16 432 WIRE 16 528 -112 528 WIRE 112 528 112 432 WIRE 112 528 16 528 WIRE 320 528 112 528 WIRE 352 528 352 304 WIRE 352 528 320 528 WIRE 544 528 544 112 WIRE 544 528 352 528 FLAG -192 368 0 FLAG -192 -144 A FLAG -144 32 B FLAG -144 208 C FLAG 304 -368 V- FLAG 320 528 V+ SYMBOL ind2 -400 -160 R0 SYMATTR InstName L1 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 -48 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L2 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -400 16 R0 SYMATTR InstName L3 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 128 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L4 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -400 192 R0 SYMATTR InstName L5 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 304 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L6 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL diode -128 -288 R0 SYMATTR InstName D1 SYMATTR Value MUR460 SYMBOL diode 0 -288 R0 SYMATTR InstName D2 SYMATTR Value MUR460 SYMBOL diode 96 -288 R0 SYMATTR InstName D3 SYMATTR Value MUR460 SYMBOL diode -128 368 R0 SYMATTR InstName D4 SYMATTR Value MUR460 SYMBOL diode 0 368 R0 SYMATTR InstName D5 SYMATTR Value MUR460 SYMBOL diode 96 368 R0 SYMATTR InstName D6 SYMATTR Value MUR460 SYMBOL res 528 16 R0 SYMATTR InstName R1 SYMATTR Value 100 SYMBOL voltage -768 -160 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value SINE(0 120 60 0 0 0) SYMBOL voltage -768 16 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 120 60 0 0 120) SYMBOL voltage -768 176 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value SINE(0 120 60 0 0 240) SYMBOL res -464 512 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R3 SYMATTR Value 1G SYMBOL cap 320 -192 R0 SYMATTR InstName C1 SYMATTR Value 1000? SYMATTR SpiceLine V=250 Irms=20 Rser=.5 Lser=20u SYMBOL cap 336 240 R0 SYMATTR InstName C2 SYMATTR Value 1000? SYMATTR SpiceLine V=250 Irms=20 Rser=.5 Lser=20u TEXT -552 -128 Left 0 !k12 L1 L2 .98 TEXT -560 72 Left 0 !k34 L3 L4 .98 TEXT -552 232 Left 0 !K56 L5 L6 .98 TEXT -640 416 Left 0 !.tran 0 300m 0 10u And Version 4 SHEET 1 880 680 WIRE 16 -368 -112 -368 WIRE 112 -368 16 -368 WIRE 176 -368 112 -368 WIRE 304 -368 256 -368 WIRE 336 -368 304 -368 WIRE 464 -368 336 -368 WIRE 544 -368 464 -368 WIRE -112 -288 -112 -368 WIRE 16 -288 16 -368 WIRE 112 -288 112 -368 WIRE 336 -192 336 -368 WIRE -384 -176 -768 -176 WIRE 464 -176 464 -368 WIRE -768 -144 -768 -176 WIRE -384 -144 -384 -176 WIRE -192 -144 -288 -144 WIRE -112 -144 -112 -224 WIRE -112 -144 -192 -144 WIRE -112 -128 -112 -144 WIRE 160 -128 -112 -128 WIRE 272 -128 240 -128 WIRE -768 -64 -832 -64 WIRE -384 -64 -480 -64 WIRE -192 -64 -288 -64 WIRE -384 0 -768 0 WIRE 272 0 272 -128 WIRE 464 0 464 -96 WIRE 464 0 272 0 WIRE -768 32 -768 0 WIRE -384 32 -384 0 WIRE -192 32 -192 -64 WIRE -192 32 -288 32 WIRE -144 32 -192 32 WIRE 16 32 16 -224 WIRE 16 32 -144 32 WIRE 160 32 16 32 WIRE 272 32 272 0 WIRE 272 32 240 32 WIRE 544 32 544 -368 WIRE 464 48 464 0 WIRE 464 48 416 48 WIRE 336 64 336 -128 WIRE 352 64 336 64 WIRE -832 112 -832 -64 WIRE -768 112 -832 112 WIRE -480 112 -480 -64 WIRE -384 112 -480 112 WIRE -192 112 -288 112 WIRE 464 160 464 48 WIRE -384 176 -768 176 WIRE -768 192 -768 176 WIRE -384 208 -384 176 WIRE -192 208 -192 112 WIRE -192 208 -288 208 WIRE -144 208 -192 208 WIRE 112 208 112 -224 WIRE 112 208 -144 208 WIRE 160 208 112 208 WIRE 272 208 272 32 WIRE 272 208 240 208 WIRE 352 240 352 64 WIRE -112 288 -112 -128 WIRE -112 288 -288 288 WIRE -832 320 -832 112 WIRE -768 320 -768 272 WIRE -768 320 -832 320 WIRE -736 320 -768 320 WIRE -480 320 -480 112 WIRE -480 320 -736 320 WIRE -384 320 -384 288 WIRE -384 320 -480 320 WIRE -112 368 -112 288 WIRE 16 368 16 32 WIRE 112 368 112 208 WIRE -736 528 -736 320 WIRE -560 528 -736 528 WIRE -336 528 -480 528 WIRE -240 528 -336 528 WIRE -112 528 -112 432 WIRE 16 528 16 432 WIRE 16 528 -112 528 WIRE 112 528 112 432 WIRE 112 528 16 528 WIRE 192 528 112 528 WIRE 320 528 272 528 WIRE 352 528 352 304 WIRE 352 528 320 528 WIRE 464 528 464 240 WIRE 464 528 352 528 WIRE 544 528 544 112 WIRE 544 528 464 528 WIRE -336 576 -336 528 WIRE -240 592 -240 528 WIRE 416 592 416 48 WIRE 416 592 -240 592 FLAG -192 -144 A FLAG -144 32 B FLAG -144 208 C FLAG 304 -368 V- FLAG 320 528 V+ FLAG -336 576 0 SYMBOL ind2 -400 -160 R0 SYMATTR InstName L1 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 -48 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L2 SYMATTR Value 40m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -400 16 R0 SYMATTR InstName L3 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 128 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L4 SYMATTR Value 40m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -400 192 R0 SYMATTR InstName L5 SYMATTR Value 20m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL ind2 -272 304 R180 WINDOW 0 36 80 Left 0 WINDOW 3 36 40 Left 0 SYMATTR InstName L6 SYMATTR Value 40m SYMATTR Type ind SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL diode -128 -288 R0 SYMATTR InstName D1 SYMATTR Value MUR460 SYMBOL diode 0 -288 R0 SYMATTR InstName D2 SYMATTR Value MUR460 SYMBOL diode 96 -288 R0 SYMATTR InstName D3 SYMATTR Value MUR460 SYMBOL diode -128 368 R0 SYMATTR InstName D4 SYMATTR Value MUR460 SYMBOL diode 0 368 R0 SYMATTR InstName D5 SYMATTR Value MUR460 SYMBOL diode 96 368 R0 SYMATTR InstName D6 SYMATTR Value MUR460 SYMBOL res 528 16 R0 SYMATTR InstName R1 SYMATTR Value 100 SYMBOL voltage -768 -160 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value SINE(0 120 60 0 0 0) SYMBOL voltage -768 16 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 120 60 0 0 120) SYMBOL voltage -768 176 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value SINE(0 120 60 0 0 240) SYMBOL res -464 512 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R3 SYMATTR Value 1G SYMBOL cap 320 -192 R0 SYMATTR InstName C1 SYMATTR Value 1000? SYMATTR SpiceLine V=250 Irms=20 Rser=.5 Lser=20u SYMBOL cap 336 240 R0 SYMATTR InstName C2 SYMATTR Value 1000? SYMATTR SpiceLine V=250 Irms=20 Rser=.5 Lser=20u SYMBOL ind 160 -352 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 5 56 VBottom 0 SYMATTR InstName L7 SYMATTR Value 200n SYMATTR SpiceLine Ipk=10 Rser=,5 SYMBOL res 448 -192 R0 SYMATTR InstName R2 SYMATTR Value 1000 SYMBOL res 448 144 R0 SYMATTR InstName R4 SYMATTR Value 1000 SYMBOL ind 176 544 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 5 56 VBottom 0 SYMATTR InstName L8 SYMATTR Value 200n SYMATTR SpiceLine Ipk=10 Rser=.5 SYMBOL res 256 -144 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R5 SYMATTR Value 2k SYMBOL res 256 16 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R6 SYMATTR Value 2k SYMBOL res 256 192 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R7 SYMATTR Value 2k TEXT -552 -128 Left 0 !k12 L1 L2 .98 TEXT -560 72 Left 0 !k34 L3 L4 .98 TEXT -552 232 Left 0 !K56 L5 L6 .98 TEXT -640 416 Left 0 !.tran 0 200m 0 10u
From: JosephKK on 3 Jan 2010 15:12 On Tue, 29 Dec 2009 06:41:13 -0800 (PST), MooseFET <kensmith(a)rahul.net> wrote: >On Dec 29, 5:17 am, "Tim Williams" <tmoran...(a)charter.net> wrote: >> PFC is a flyback thing. But flybacks suck over 100W, where forward looks >> better. But forward sucks over wide duty cycle ranges. What do they do, >> just bigger flybacks? Nothing at all? > >At modestly larger that 100W the flyback booster method still works >ok. The bulk of the power is transfered by the booster when its boost >ratio is small. To handle the very wide duty cycle dropping the >frequency as the mains nears its peak works. > >Multiple boosters running out of phase will let you go up to higher >power levels and the ripple tends to cancel. > >Other designs do use various sorts of forward converters. No matter >what you do, you need to have a core somewhere that has a significant >energy storage. To make the forward converter method work, the output >side inductor has to do the storing. Going up in frequency, keeps the >inductor's mechanical size smallish. Not only that, i tripped over an alternate reading.
From: Paul Keinanen on 4 Jan 2010 00:53 On Tue, 29 Dec 2009 13:44:36 GMT, Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >On a sunny day (Tue, 29 Dec 2009 07:17:31 -0600) it happened "Tim Williams" ><tmoranwms(a)charter.net> wrote in <Yhn_m.18015$wC3.5829(a)newsfe07.iad>: > >>PFC is a flyback thing. But flybacks suck over 100W, where forward looks >>better. But forward sucks over wide duty cycle ranges. What do they do, >>just bigger flybacks? Nothing at all? >> >>Tim >> >>-- >>Deep Friar: a very philosophical monk. >>Website: http://webpages.charter.net/dawill/tmoranwms > >For much higher power 3 phase rectifiers are used. >That leaves only a small ripple. >I am not sure if you need PFC in such a case. The ordinary 3 phase 6 pulse rectifier is a quite nasty polluter of the mains. To reduce the harmonics, 12 pulse rectifiers have been used, with one set of rectifiers connected to the wye windings and the other set from separate delta windings. For high power systems, you still are going to need a medium/low voltage transformer on site, so it is not a big deal having separate wye and delta secondary windings on that transformer. If you want to get away with the heavy 50 Hz transformer, there seems to be various more or less patented 3 phase systems using flyback etc. systems to reduce the PFC, but these seems to be hugely complex and have special floating requirements for the DC side. If floating output or voltages other than those obtainable by simple rectifiers are required, it might be easier to simply get three single phase SMPS with PFC at the input and connect the DC outputs in parallel. If the input voltage ratings permit, instead of wye, connect the inputs into delta to avoid any mains neutral polluting and also allow higher voltage and hence higher power (1.7x) for a specific semiconductor amperage.
From: Fred Bartoli on 4 Jan 2010 04:30 Paul Keinanen a �crit : > On Tue, 29 Dec 2009 13:44:36 GMT, Jan Panteltje > <pNaonStpealmtje(a)yahoo.com> wrote: > >> On a sunny day (Tue, 29 Dec 2009 07:17:31 -0600) it happened "Tim Williams" >> <tmoranwms(a)charter.net> wrote in <Yhn_m.18015$wC3.5829(a)newsfe07.iad>: >> >>> PFC is a flyback thing. But flybacks suck over 100W, where forward looks >>> better. But forward sucks over wide duty cycle ranges. What do they do, >>> just bigger flybacks? Nothing at all? >>> >>> Tim >>> >>> -- >>> Deep Friar: a very philosophical monk. >>> Website: http://webpages.charter.net/dawill/tmoranwms >> For much higher power 3 phase rectifiers are used. >> That leaves only a small ripple. >> I am not sure if you need PFC in such a case. > > The ordinary 3 phase 6 pulse rectifier is a quite nasty polluter of > the mains. > > To reduce the harmonics, 12 pulse rectifiers have been used, with one > set of rectifiers connected to the wye windings and the other set from > separate delta windings. For high power systems, you still are going > to need a medium/low voltage transformer on site, so it is not a big > deal having separate wye and delta secondary windings on that > transformer. > > If you want to get away with the heavy 50 Hz transformer, there seems > to be various more or less patented 3 phase systems using flyback etc. > systems to reduce the PFC, but these seems to be hugely complex and > have special floating requirements for the DC side. > > If floating output or voltages other than those obtainable by simple > rectifiers are required, it might be easier to simply get three single > phase SMPS with PFC at the input and connect the DC outputs in > parallel. > > If the input voltage ratings permit, instead of wye, connect the > inputs into delta to avoid any mains neutral polluting and also allow > higher voltage and hence higher power (1.7x) for a specific > semiconductor amperage. > For Tim, which I suspect is asking this for his induction heater, it might be easier to use his bridge so as to draw sine current. The output power will be sine squared but who cares? And that'll put more requirement on some components for the same average output power, but it'll avoid a full PFC stage which won't do good on efficiency, and this might have a higher overall efficiency. -- Thanks, Fred.
From: Tim Williams on 4 Jan 2010 06:37
"Fred Bartoli" <" "> wrote in message news:4b41b520$0$30367$426a74cc(a)news.free.fr... > For Tim, which I suspect is asking this for his induction heater, it might > be easier to use his bridge so as to draw sine current. Yup. But it's also a good general question. > The output power will be sine squared but who cares? And that'll put more > requirement on some components for the same average output power, but > it'll avoid a full PFC stage which won't do good on efficiency, and this > might have a higher overall efficiency. I may do this, and it even makes the coil hum with a pleasing growl. The downside is it puts 120Hz into all my loop, and makes scoping the inverter fairly useless. Constant current mode would have to be slower than 120Hz, and I'm not sure how 120Hz will affect the PLL. Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms |