Electrical Parameters Of Dsp-based Test System To Study

With the development of power electronics technology during the last two decades, its application in engineering practice has become wider and wider. But, the harmonic pollution problem brought by the device of power electronics not only block the development of power electronics technology, but also cause severe harm in electric power system. In order to eliminate the harm brought by the wave aberrance of voltage and current, it is necessary to control the harmonic wave and compensate the reactive power. So it is very important to test the electric parameters. In this paper, the research of electric parameters test based on DSP TMS320F2812 has been done.The parameters needed to be calculated in this paper are: the average value of volts d.c. and current d.c, the virtual value of volts a.c. and current a.c, alternating frequency, power factor and harmonic wave content. In the paper, mathematics model of electric parameters test based instantaneous reactive power is proposed, the content of harmonic wave is analyzed using DFT, and the sampling frequency is confirmed using sine signal sample theory.Secondly, the hardware circuit of this paper can be divided into data sampling module, peripheral equipment interface circuit and frequency test circuit. The data sampling module includes signal consecution circuit and A/D conversion circuit. Peripheral equipment interface circuit includes peripheral RAM extend circuit, USB data communication circuit, LCD interface circuit, minitype printer interface circuit and CAN bus interface circuit. The frequency test circuit is used to measure the frequency of alternating signal. This paper also does the research of Electromagnetic Compatibility (EMC) based on the above hardware circuit.Thirdly, this paper programs the electric parameters calculation software and hardware driver software. Electric parameters calculation software includes data pretreatment software, data sampling software, data test software, alternating signal frequency field analyzing software, alternating signal frequency test software and least square method data correcting software. The driver software includes peripheral RAM extend circuit software, USB data communication circuit software, LCD interface circuit software, minitype printer interface circuit software and CAN bus interface circuit software.Finally, an airplane power supply system is tested, and the test results show its efficient and accuracy.