一种基于Hilbert数字滤波的无功功率测量方法  

A METHOD OF REACTIVE POWER MEASUREMENT BASED ON HILBERT DIGITAL FILTERING

作　　者：俎云霄[1] 庞浩[1] 李东霞[1] 王赞基[1] 

机构地区：[1]清华大学电机系,北京市100084

出　　处：《电力系统自动化》2003年第16期50-52,70,共4页Automation of Electric Power Systems

摘　　要：提出了一种基于Hilbert数字移相滤波的无功功率测量方法。该方法不仅能测量正弦电路中的无功功率 ,而且在给定的定义下 ,也适合于测量含有谐波的非正弦电路中的无功功率。由于该方法是在对电压、电流信号采样后 ,通过直接进行移相滤波和简单的数值计算测量出无功功率 ,避免了现有方法中通过测量电压、电流有效值和有功功率计算无功功率所带来的误差。此外 ,由于所设计的Hilbert数字移相滤波器具有优越的频率响应特性 ,即使对于相当高次谐波无功功率的测量 ,也能获得很高的测量准确度。所测无功功率的正负值还可以直接用于判断负载的性质。该方法在将模拟电压、电流信号转化为数字采样信号之后所进行的处理工作都是数字化的 ,设计简单、便于实现。A Hilbert digital filtering technique for reactive power measurement is proposed. The method is not only valid in the sinusoidal condition, but also in the non-sinusoidal conditions under certain definition. The reactive power is measured by firstly sampling the voltage and current signals, and then by directly implementing Hilbert digital filtering technique and some simple calculations. The errors introduced by the measurements of the active power and the root-mean-square values of voltage and current in the existing methods can be avoided. In addition, because of the excellent frequency response of the designed Hilbert filter, the high accuracy of the measurement for high harmonics can be guaranteed. Meanwhile, the positive or negative value of the measured reactive power also indicates the load characteristics. Except for A/D conversion from voltage and current signals, all procedures of the algorithm are digitally performed. Hence, the proposed method is simple and easy to be realized. The method has been used in the design of a multi-functional power instrument.

关 键 词：无功功率测量 谐波 Hilbert滤波 数字滤波 

分 类 号：TM764[电气工程—电力系统及自动化]