考虑新型拓扑结构的统一潮流控制器五端功率注入模型

Five-terminal Power Injection Model of UPFC Considering Novel Topology Structure

南京西环网中统一潮流控制器(UPFC)装置的串联侧变压器接入220kV铁北—晓庄双回线路,并联侧连接在临近的35kV燕子矶母线,这种新型拓扑结构对UPFC的系统级建模提出了更高的要求,既要考虑UPFC控制双回线路的特点,还要体现UPFC对并联侧母线及后续线路的影响。为此,文中提出了一种适用于新型拓扑结构的UPFC五端功率注入模型,在考虑串联侧控制双回线路且并联侧节点可灵活的情况下,基于注入功率法推导了该模型的数学表达式,并给出了PSASP软件下UPFC五端模型的潮流计算原理和实现方法。在该模型的基础上,进一步实现了UPFC串联侧双线控制策略,并基于南京UPFC工程实际数据进行正常运行状态和串联线路N-1故障的仿真计算,结果验证了该模型的准确性、灵活性和全面性。

In Nanjing western power grid,the series side of unified power flow controller（UPFC）device is installed on the220 kV Tiebei-Xiaozhuang double-circuit transmission line,while the parallel side of UPFC is connected to the adjacent 35 kV Yanziji bus.The novel topology structure imposes higher demand for system-level modeling of UPFC：not only double-circuit line can be controlled by series converter,but also the impact of low voltage bus and neighboring lines should be analyzed.A UPFC five-terminal power injection model considering novel topology structure is proposed,in which series part can control the power flow of double-circuit line respectively and parallel node can be flexibly connected.Based on the power injection method,the mathematical expressions of this model are derived.The power flow calculation principle in PSASP and implementation method of this model are discussed.Based on this model,the double-circuit control strategy of UPFC is established.Finally,simulation is realized in Nanjing UPFC project both under normal steady state and N-1 contingency occurred on the line of UPFC series side.The control results reveal the validity,flexibility and comprehensiveness of this proposed model.