互感器二次压降及二次负荷模拟测试系统研究

互感器二次压降及二次负荷直接关系到电能计量的误差,是电力系统必须定期检定的项目。本文研制了一套用于电力技术人员培训用的模拟测试系统,采用三相电压电流源来模拟互感器的二次侧输出,用电阻、电抗序列模拟互感器的二次负荷及压降,接线方式包括三相三线制和三相四线制两种。以数字信号处理器(TMS320F206)为核心控制器,来控制各个模拟设备的参数,并通过A/D转换和运算放大等电路来采集电压、电流、功率因数等参数,整个系统由上位机软件进行控制,采用RS485串口通讯协议。实践表明该系统具有较好的稳定性和可靠性,模拟测试的各项指标符合现场测试的技术要求。

Research on the Simulation Test System of Instrument Transformer Secondary Voltage Drop and Secondary Load

Instrument transformer secondary voltage drop and secondary load,which directly related to the energy measurement error,are items that must be periodically tested by the power system.This paper has explored a simulation test system which can imitate the field environment of training for the power technical staff.In this system,the voltage and current instrument transformer secondary output are simulated by three-phase voltage and current source,the secondary voltage drop and secondary load are simulated by resistance and reactance sequence.The wiring mode contains the three-phase three-wire system and three-phase four-wire system.The digital signal processor(TMS320F206) is adopted as the core controller to control the parameters of the various analog devices,while the A/D conversion and operational amplifier analog circuits is employed to collect voltage,current value,power factor,transformer secondary load value,etc.The entire system is controlled by the host computer software,using RS485 serial communication protocol.Experiments show that this system has high stability and reliability,and the simulated testing indicators meet the technical requirements of field-testing.