WAMS中PMU的完整周期抗混迭同步采样方法

基于全球定位系统（GPS）的同步相量测量装置（PMU）是广域测量系统（WAMS）的重要组成部分。提出一种基于GPS同步时钟和数字信号处理器（DSP）以及高速AVR单片机的双CPU同步相量测量装置；利用DSP的一个输入捕获单元捕获GPS秒脉冲并同步到32位高精度定时器，控制每个周期采样的起始时刻，利用另一个输入捕获单元捕获频率并把相应的采样周期传送给16位定时器的周期寄存器控制该完整周期的采样间隔，从而建立了完整周期抗混迭同步采样方法，避免了因频率变化而引起的采样混迭现象；利用DSP的高精度时钟配合同步信号源以提高同步时钟的可靠性。

Full Cycle Anti-aliasing Synchronized Sampling Algorithm of Phasor Measurement Units in WAMS

GPS-based synchronized phasor measurement units (PMUs) are important components in wide area measurement systems (WAMS). A new PMU design scheme and sampling algorithm with digital signal processor (DSP) and high speed AVR MCU are presented. The 1 PPS (pulse per second) of GPS is measured by one input capture unit of the DSP, and the 32-bit Timer of the DSP is synchronized by the 1 PPS to control the first sampling of a wave cycle. The frequency of the wave is measured by another input capture unit of the DSP, and the period register of 16-bit Timer of the DSP is loaded with the sampling period derived from the frequency. The measurement precision and the sampling synchronization are improved by using the full cycle anti-aliasing synchronized sampling method. The high-precision clock of DSP is incorporated with the GPS clock to improve the reliability of synchronous clock.