摘要
直流电压互感器(direct circuit voltage transformers,DCVTs)的低压输出模拟信号采用电缆传输时既无电气隔离同时易受电磁干扰,因此提出了采用光纤高线性度传输模拟信号的方案。利用双光源-光电探测器分别构成传输通道和闭环负反馈通道,负反馈通道的光电探测器变换电流反馈至输入端对电光-光电传输系数非线性进行抑制,通过控制系统模型分析了非线性抑制控制策略和非线性抑制效果,分析了模拟信号光纤传输系统的电路设计关键要素。对模拟信号光纤传输系统进行开环传输和闭环反馈传输非线性特性对比测试,结果表明,通过闭环负反馈的传输方案将模拟信号光纤传输非线性误差从百分之几提高到了±0.05%以内。最后将模拟信号光纤传输系统应用到DCVT中进行了线性度测试,试验结果表明:模拟信号光纤传输系统能很好地适用于直流配电网中模拟信号电气隔离和消除电磁干扰的应用需求。
The low-voltage output analog signals of direct circuit voltage transformers(DCVTs)are transmitted through cables without electrical isolation and are susceptible to electromagnetic interference.A scheme for transmitting analog signals with high linearity using optical fibers is designed.Using dual light sources and photodetectors to form a transmission channel and a closedloop negative feedback channel,the photodetector in the negative feedback channel converts the current and feeds it back to the input end to suppress the nonlinearity of the electro-optical transmission coefficient.The nonlinear suppression control strategy and effect are analyzed through a control system model,and the key elements of the circuit design of the analog signal fiber optic transmission system are analyzed.A comparative test is conducted on the nonlinear characteristics of open-loop transmission and closed-loop feedback transmission of analog signal fiber optic transmission systems.The results show that the nonlinear error of analog signal fiber optic transmission is reduced from a few percent to within±0.05%through the closed-loop negative feedback transmission scheme.Finally,the analog signal fiber optic transmission system is applied to DCVT for linearity testing.The experimental results show that the analog signal fiber optic transmission system can be well applied to the application requirements of electrical isolation and elimination of electromagnetic interference of analog signals in DC distribution networks.
作者
宋宏天
胡珊珊
王保帅
王宗义
肖霞
SONG Hongtian;HU Shanshan;WANG Baoshuai;WANG Zongyi;XIAO Xia(Electric Power Research Institute,CSG,Guangzhou 510663,China;Guangdong Provincial Key Laboratory of Intelligent Measurement and Advanced Metering of Power Grid,Guangzhou 510663,China;Huazhong University of Science and Technology,Wuhan 430000,China)
出处
《南方电网技术》
北大核心
2025年第7期112-118,共7页
Southern Power System Technology
基金
广东省科技计划项目(2021B1212050014)
中国南方电网有限责任公司科技项目(KYKJXM20222007)。
关键词
高线性度
模拟信号光纤传输
直流电压互感器
闭环负反馈
high linearity
analog signal fiber optic transmission
direct circuit voltage transformer(DCVT)
closed loop negative feedback
