冲击负荷接入电网的电能质量分析与治理方案研究

Research of the power quality problem and treatment scheme for impact loads connected into Chongqing power system

随着冲击性负荷的日益增多,迫切需要对大量冲击性负荷接入电网时所引发的电能质量问题进行有效的分析。结合重庆电网,提出了分析大量冲击性负荷接入系统时的电能质量评估方法并给出了综合的治理方案。首先基于电流的实测数据建立了冲击负荷的新型拟合模型,并结合ward等值理论和戴维南定理多电势转化方法搭建了重庆地区的等值电网,将冲击负荷模型接入等值电网中,以此为平台研究了多个冲击性负荷接入对重庆电网电能质量的综合影响。针对电能质量超标的情况,分析了提高冲击负荷接入的电压等级、加装滤波器或SVC等治理措施,并结合重庆电网冲击负荷实测电能质量数据提出了治理方案。在PSCAD中搭建了仿真模型,验证了分析结果的有效性和准确度,为冲击负荷接入重庆电网的综合治理提供了理论参考。

As the number of impact loads increases, there is an urgent need to develop a valid method to analyze the power quality problems caused by these multiple impact loads. Taking the Chongqing electric power system as an example, the paper presents an evaluation method for the power quality problem when multiple impact loads are connected into the system, and proposes a comprehensive treatment scheme. A new impact load model is constructed based on the fitting measured data, while the regional equivalent grid is established based on the Ward equivalent and multi-potential equivalent in Thevenin Theorem, then the combined effects on the power quality of Chongqing Grid are studied when multiple impact load models access the equivalent grid. For the case of excessive power quality, several control measures are analyzed, such as increasing access voltage level, installing filter or SVC, and treatment schemes are proposed based on the measured power quality data of impact loads in Chongqing Grid. The validity and accuracy of analysis results are verified by building simulation model in PSCAD, and theoretical reference for the comprehensive treatment when impact loads access Chongqing Grid is provided.