关键词: 功率变换器, 谐波畸变, 恒功率负载, 功率因数, 电力系统

Abstract:

According to the operational principle of a closed-loop regulated high power factor(HPF) pulse width modulation (PWM) rectifier, a simulation model of alternating current (AC) constant power load (CPL) is proposed. This model is implemented in MATLAB software. The input current of this model is made to follow the input voltage and the consistence in their waveforms is achieved. Whether the harmonics contained in the input voltage are considered or neglected, this model can calculate the root mean square (RMS) of the input current and then generate an appropriate current waveform. Therefore the input power of the model is kept constant and the influence of harmonics is reflected in the waveform of the input current. Compared with the experimental results of a practical PWM rectifier behaving as a constant power load, the simulation results in MATLAB software verify the covalidity of this model.

Key words: power converters, harmonic distortion, constant power load, electric power factor, electric power systems