Patent ID: 9543859
Date: 2017-01-10
CPC Classifications: H02J,H02M,Y02E

Claim:
1. A control system for controlling a power inverter, the system comprising: an active power subcontroller, said active power subcontroller receiving a difference between a reference P value and an estimated P value, an output of said active power subcontroller being used to determine voltage and current outputs of said power inverter; a reactive power subcontroller, said reactive power subcontroller receiving a difference between a reference Q value and an estimated Q value, an output of said reactive power subcontroller being used to determine voltage and current outputs of said power inverter; an active/reactive power estimator for estimating said estimated P value and said estimated Q value based on outputs of said power inverter, said estimator receiving voltage and current outputs of said power inverter; wherein said estimated P value is an estimate of a P value and said reference P value is a reference for said P value, said P value being a DC offset of an instantaneous power of a power grid to which said power inverter is connected and said estimated Q value is an estimate of a Q value and said reference Q value is a reference for said Q value, said Q value being a coefficient of a sine component of said instantaneous power of said power grid; and wherein said estimator estimates said estimated P value and said estimated Q value by implementing: where p {circumflex over (P)} is an estimated value for said P value; {circumflex over (Q)} is an estimated value for said Q value; {tilde over (P)} {circumflex over (θ)} is an estimated value for an unknown variable θ; {dot over ({circumflex over (P)})} is a derivative of said estimated value for said P value; γ {dot over ({circumflex over (Q)})} is a derivative of said estimated value for said Q value.