Nevertheless, the conventional method becomes complex in determining the reference signal if the system's ac main voltage varied. Thus, this paper proposes a ...
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−
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+
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_
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C2
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Vref =
V peak Vdc
(vac + ωLiac )
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V peak V dc
[v
ac
]
+ (ω L ) i ac − ωL v ac i ac VLQ (θ i − θ v )
ª v VLQ θ v + iac ωL FRVθ i º ∠θ ref = WDQ − « ac » «¬ vac FRVθ v − iac ωL VLQ θ i »¼
B. Proposed Simplified Equation 8QIRUWXQDWHO\ WKH FRQYHQWLRQDO HTXDWLRQ EHFRPHV FRPSOLFDWHGZKHQWKHDFPDLQYROWDJHvacDWQRPLQDOVWDQGDUG JULG YROWDJH IOXFWXDWHG ,W PHDQV WKH UHIHUHQFH VLJQDO Vref DOZD\VKDYHWREHUHFDOFXODWHGRQFHWKHDFPDLQYROWDJHvacLV YDULHG 7KHUHIRUH WKH VLPSOLILHG HTXDWLRQ LV FDSDEOH WR WDFNOH WKH YDULDWLRQ RI WKH DF PDLQ YROWDJH vac 6LPLODU WR WKH FRQYHQWLRQDO HTXDWLRQ WKH VLPSOLILHG HTXDWLRQ LV XVHG WR GHWHUPLQHWKHPDJQLWXGHDQGWKHSKDVHDQJOHRIWKHUHIHUHQFH VLJQDO Vref. 7KURXJK WKLV PHWKRG WKH FRPSOH[LW\ RI WKH UHIHUHQFHVLJQDOVrefLVUHGXFHGDQGWKHFRPSXWDWLRQDOEXUGHQLV GHFUHDVHGFRQFXUUHQWO\ 7KHPDLQSXUSRVHRIWKHSURSRVHGPHWKRGLVWRUHGXFHWKH FRPSOH[LW\RIWKHHTXDWLRQ,WLQLWLDWHVDWWKHQHZYDOXHRIWKH DF PDLQ YROWDJH vac,new %HDU LQ PLQG WKLV PHWKRG RSHUDWHV XQGHU WKH VDPH GHPDQG RXWSXW SRZHU 7KHUHIRUH WKH QHZ DF PDLQ FXUUHQW iac,new KDYH WR EH UHPDLQHG LGHQWLFDOO\ ZLWK WKH GHVLUHGRXWSXWFXUUHQWiac7KHH[SUHVVLRQVIRUWKHQHZDFPDLQ YROWDJH vac,new WKH QHZ DF PDLQ FXUUHQW iac,new DQG WKH QHZ DSSDUHQWSRZHU6QHZDUHLQGLFDWHGEHORZ
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vac new = vac + Δvac
iac new = iac + Δiac
S new = vac new iac new
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Vref new
º V peak ª v ac new + (ωL ) iav new « » = Vdc «− ωL v ac new iac new VLQ (θ i − θ v )» ¬ ¼
ª v ac new ∠θ ref new = WDQ − « «¬ v ac new
VLQ θ v + i ac new ωL FRV θ i º » FRV θ v − i ac new ωL VLQ θ i »¼
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Vref new = Vref + ΔVref
ΔVref
§ V peak = ¨¨ © Vdc
· ¸¸ ¹
(
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7$%/(,, ѐvac (%)
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k · ¸ ¸© + k ¹ ¹
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ª º ωLP ∠θ ref new = WDQ − « » + v n ω LQ ac ¬ ¼
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Unit
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9
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9
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9
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_Vref,new¶_ 9
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סșref,new¶ UDGV
Equation
63(&,),&$7,212)7+(6,1*/(3+$6(+$/)%5,'*( ,19(57(5 Value
-5
ѐvac (%)
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Parameters
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