基于高速采集卡有载分接开关交流测试系统的设计

Design of AC Test System for On-load Tap Changer Based on High Speed Data Acquisition Card

为了提高电网运行的稳定和可靠性,需要对变压器调压的核心部件有载分接开关实施动态监测,传统的直流监测系统在波形分析检测上存在一些缺陷,文中介绍的测试系统采用交流测试方法,弥补了直流测试中的一些不足。对于测试过程中信号的数据采集部分,传统的采集方式使用A/D转换器将信号转换为模拟数字量送入到单片机,而对于需要多路信号同时采集解决的办法是采用采样保持电路与多路选择开关的配合来完成数据同时采集。文中采用研华公司的高速数据采集卡,与上位机相连,对于需要采集的信号可以高速快捷的送入上位机中,不仅省去了传统电路的繁冗,且操作简便,方便实现多路信号同时采集。在上位机使用Delphi开发测试软件,配合数据采集卡完成了有载分接开关的动态监测,最后验证了测试系统的正确性。

To improve the reliability and stability of a power grid, real-time monitoring of the core component in a transformer-on-load tap-changer （OLTC） is necessary. However, the conventional DC real-time monitoring system is deficient. As a result, an AC real-time monitoring method is introduced in this paper to make up the shortcomings of the DC monitoring system. In conventional data acquisition process, A/D converter is adopted, and the combination of sample-and-hold circuit and analog switch is employed to accomplish multi-channel data acquisition at same time. The authors use a high-speed data acquisition card, which is simple in both circuit structure and operation, for the multi-channel data acquisition. The real-time monitoring of OLTC is completed by developing a test software with Delphi. This test system is verified experimentally.