CAJ | 학술논문

以光伏并网逆变器在电网不对称故障下的控制策略为研究对象，建立了并网逆变器在电网发生不对称故障时的数学模型，并对功率特性进行了分析，进而提出了电网不对称故障下基于模型预测电流控制的光伏并网逆变器控制策略，并在 PSCAD/EMTDC 平台上分别进行了以抑制有功功率波动为目标和抑制负序分量电流为目标的仿真实验。研究结果表明，模型预测电流控制方法能够使逆变器的输出电流迅速地跟随参考电流指令，具有良好的动稳态特性。在电网不对称故障下，不需要电网电流进行相序分解便可以实现对各序电流的有效控制，能够抑制三相电网电压不对称所引起的有功功率波动和负序电流，该方法控制算法简单，数字信号处理实现容易，在光伏逆变器的控制中具有工程价值。
이광복병망역변기재전망불대칭고장하적공제책략위연구대상，건립료병망역변기재전망발생불대칭고장시적수학모형，병대공솔특성진행료분석，진이제출료전망불대칭고장하기우모형예측전류공제적광복병망역변기공제책략，병재 PSCAD/EMTDC 평태상분별진행료이억제유공공솔파동위목표화억제부서분량전류위목표적방진실험。연구결과표명，모형예측전류공제방법능구사역변기적수출전류신속지근수삼고전류지령，구유량호적동은태특성。재전망불대칭고장하，불수요전망전류진행상서분해편가이실현대각서전류적유효공제，능구억제삼상전망전압불대칭소인기적유공공솔파동화부서전류，해방법공제산법간단，수자신호처리실현용역，재광복역변기적공제중구유공정개치。
The control strategy for the photovoltaic inverter under unsymmetrical fault in power grid is focused on. A mathematical model of the grid-connection inverter when unsymmetrical fault occurs in the grid is built and an analysis of power characteristic is made.Then the photovoltaic inverter control strategy based on model prediction current is put forward. Simulation verifications and analysis of damping active power fluctuation and negative sequence component current are made on a PSCAD/EMTDC platform.The results show that the model prediction current control method is able to make the output current of the inverter quickly follow the reference current with good dynamic and static characteristics. Under the unsymmetrical fault in the grid,it effectively realizes the control of each sequence current without decomposing the grid current phase sequence,thus restraining active power fluctuation and negative sequence current caused by the unsymmetrical fault. Simple and easily processed digitally,this method is of great engineering value in photovoltaic inverter control. This work is supported by Fundamental Research Funds for the Central Universities(No.12MS33).