应用LPC2131开发PLC调速器测频单元

Frequency measurement unit exploitation of PLC hydro-turbine governor based on LPC2131

针对PLC调速器频率测量部分存在的不足,开发出一种基于LPC2131微控制器的频率测量单元。利用其捕获功能模块对整形后频率信号捕获、计算得到信号周期计数值,再将该周期计数值通过UART通信口发送至PLC,在PLC中完成信号频率值计算。测试结果表明,由于采用信号上升沿及下降沿同时捕获以及高速串行通信,不但提高了频率信号的响应速度,而且很好地解决了并行通信存在的数据传输不同步的问题。

For the deficiency in the frequency measurement unit of PLC hydro-turbine governor, another frequency measure- ment unit which was based on LPC2131 was exploitation. By using its function of capture to capture the frequency of the signal after shaping we can get the value of the signal cycle, and then send the value of the cycle to the PLC through the UART interface communication. The frequency of the signal value is calculated in the PLC . Test results showed that it is not only improved the speed of the frequency response signal but also gave a very good solution to the problem of the parallel data communication does not synchronization by using adopting the capture both rising edge and falling edge and serial communication.