准同步采样法在配电综合测控仪中的应用

Application of the quasi-synchronous sampling method in the measuring control instrument for electricity

通过研究准同步采样法,分析准同步采样法准确度与频率偏差的关系,提出通过减少频率偏差来提高准同步采样法准确度的两种方法,提出准确计算信号频率的公式。计算机仿真结果表明该方法能有效提高测量信号的有效值和谐波的准确度。最后把准同步采样法应用于配电综合测控仪中,进行硬件和软件设计,实现了仪器体积小,抗干扰能力强,而且测量速度快,测量精度高的目标。

This paper analyzes the relation between the accuracy of quasi-synchronous sampling method and frequency deviation through studying the quasi-synchronous sampling method. Two methods of improving the accuracy of the quasi-synchronous sampling method through reducing frequency deviation are presented. The formula for accurately calculating the frequency is given. The simulation results show this method can improve the RMS value of the measured signal and the accuracy of the harmonic. Finally, this method is applied in the measuring control instrument for electricity. The purposes of small volume, strong anti-jamming ability, high measuring speed and measuring accuracy of this instrument are achieved.