A Study On Measurement Of Power System Frequency Based On DSP

Firstly, this paper explains the general situation of development about the theory of digital signal, introduces the characteristics and the current situation development of the digital signal processor, and discusses the application of digital signal processing in the electric measurement.Secondary, this paper expatiates on the harmonic generation, harmonic harm, harmonic analysis and the hardware for measuring harmonics, analyzes and discusses the method applied to measure harmonics. In the paper, the problem of spectrum leakage appearing when adopting Fourier progression in harmonic analysis is analyzed and discussed, and three main methods to solve spectrum leakage are described. Through discussing the samples of AC signal, the basic method to solve spectrum leakage is pointed out, which is to guarantee the same pace between signal frequency and sampling frequency. Because the fundamental frequency of power system is not invariable, it needs to be tracked and measured. Thirdly, power system frequency as weighing the quality of electric energy needs to be monitored; on the other hand, as the important feedback state for implementing the security and steady controls, it requires being real-time constructed again. Therefore, the paper mainly discusses the pluses and minuses of the multifarious frequency estimation algorithms, and develops an adaptive method of evaluation on DFT for power system frequency, which is based on the equal-angle sampling principle. According to different applications, the corresponding algorithm procedures are provided. Some simulation results arelisted to test that this algorithm can satisfy the demands of frequency measurement for real-time, fast and accuracy, and establish a solid foundation for suppressing spectrum leakage and detecting harmony.Lastly, in order to verify the feasibility of the algorithm, a fast data collecting and detecting system is designed based on TMS320VC5402 DSP, which is used to analyze and measure the harmonics and some parameters of the triphase distorted electrical signal. This system realizes fast data collecting through connecting the McBSP of DSP with AD, and adopts SCM as the host computer, which communicates the data with TMS320VC5402 through the HPI of DSP. The realization process of Bootloader is described and some experimental results are listed in this paper.