由于其高节能性，越来越多的变速可变输出高压交流设备单元继续安装；然而，由于这些功率转换器中使用的半导体器件固有的非线性，提供给电机的电压和电流波形不是纯正弦的，因此含有极高的谐波含量。由于仪表频率响应、范围、内部阻抗等方面的限制，许多可用仪器无法准确测量失真的电流、功率或能量。本研究的目的是获得一系列准确的相关数据，用于定义仪器类型、仪器规格，仪器使用mat将准确测量固态电源和变速电机系统（从1/2 hp到ISO hp）电机引线中的电压、电流、瓦特和瓦特。 该测量的精度应至少与模拟RMS功率型仪表相同，最好更好，满量程为0.2%，量程变化为2到1。

An increasing number of variable-speed variable-output HV AC equipment units continue being installed because of their high energy savings; however, because of the non-linearity inherent in the semiconductor devices used in these power converters, the voltage and current waveforms supplied to the motors are not purely sinusoidal and thus contain extremely high harmonic contents. Many available instruments do not measure mis distorted current, power or energy accurately due to limitations in the meter frequency response, range, internal impedance, etc.The objective of this research was to obtain a body of accurate and relative data which can be used to define the instrument type, instrument specifications, and instrument use mat will result in accurately measuring the volts, current, watts and watthours into the solid state power supply and into the motor leads of the variable speed motor systems ranging from 1/2 hp to ISO hp. The accuracy of this measurement should be at least as good and preferably better man traditionally available on analogue RMS power type meters, 0.2% full scale with 2 to 1 scale changes.