Patent ID: 11862982
Assignee: NANJING UNIVERSITY OF POSTS AND TELECOMMUNICATIONS
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G  Y | IPC G  H

Claim 2:
3. The method according to claim 1, wherein the determining, according to the primary frequency regulation predictive values, optimal control sequences of inverters of the power generation units at different times based on a pre-established inverter active power model, comprises:
when primary frequency regulation is started under a condition where a system frequency is lower than a rated frequency, determining, based on the inverter active power model, the optimal control sequences of the inverters of the power generation units at different times by means of an objective function for predictive control, wherein the objective function for predictive control is expressed as:, min
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wherein, Np is a predictive domain length, N is the number of the power generation units of the new energy power station, λi(k) is a weight coefficient of an ith power generation unit, Φi(k)=−biΔPi(k),bi={0,1} is a cost function of the ith power generation unit, and ΔPi(k) is a power variation of the ith power generation unit at the time k with respect to a time k−1; Φi(k+j|k) represents a Φi value at a time k+j predicted at the time k;
constraints of the objective function are:, λ
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x(k+1)=Ax(k)+Bu(k)

wherein, Ci(k) is a confidence of the ith power generation unit at the time k, and an initial value of Ci(k) is 1; ΔPimax and ΔPimin are an upper limit and a lower limit of the primary frequency regulation predictive values respectively, ΔP is total power required for the new energy power station to participate in primary frequency regulation, ΔPtotal is a total predictive value for the new energy power station to participate in primary frequency regulation, Pi(k) is active power of the ith power generation unit at the time k, Δf is a system frequency deviation, and K is a primary frequency regulation coefficient of the new energy power station; x(k+1)=Ax(k)+Bu(k) is the active power model of the inverters in the discrete time;
the optimal control sequences are:

u*(k)=[ΔPref*(k|k),ΔPref*(k+1|k), . . . ,ΔPref*(k+Nc|k)]

wherein, u*(k) is the optimal control sequence at the time k, Nc is a control domain length, ΔPref*(k+i|k),i=1, 2, . . . Nc is a control quantity at a time k+i of the inverters predicted at the time k, and ΔPref*(k|k) is a control quantity at the time k of the inverters.