The Research And Realization Of Power Quality On-line Monitor Based On DSP

With the increasing usage of power electronic devices and sensitive loads in power systems, power quality has attracted the attention of power engineers over the past years. The interest in power quality has increased during the latest years. A power quality problem can be defined:problem due to frequency, voltage regulation, voltage dips, flicker, transients, harmonics, and power factor and 3 phase imbalance. With the rising of the power quality monitoring current demand, this paper presents a design and realization of power quality on-line monitoring device based on a single-chip DSP TMS320F2812. This system mainly uses TMS320F2812's multi-channel buffered serial port (McBSP) and multi-channel high-speed synchronous AD sampling chip AD73360 to realize the power parameters of the real-time acquisition. This design takes advantage of the DSP chip and network-chip W5100 to achieve the Ethernet communication. So the design realizes the real-time analysis, storage and remote reporting of various indicators of power quality. The system based on single-chip DSP in order to make it compact, easy to implement, cost reduction, and well adapted to the power quality monitoring requirements of power system.This paper focuses on the key parameters of power quality in the calculation methods, such as arguably the calculation of reactive power, harmonic power calculation, voltage fluctuations and flicker and so on. Compared and simulated several kinds of reactive power calculation methods, this paper gets a conclusion that the Hilbert filter method of non-sine wave reactive power can get a high accuracy. As for harmonic algorithm, after comparing a variety of methods, the paper realizes two harmonics algorithms base on DSP development environment, a general FFT and quasi-synchronous DFT. Finaly, it concludes that quasi-synchronous DFT method can correct synchronization error introduced by a small drift under the prerequisite of grid frequency and obtain a more satisfactory accuracy increase without the cost of hardware.Based on a large number of the references, this paper analyzes and compares the existing algorithms, with the consideration of accuracy and usefulness. The paper presents a complete hardware and software design implementation method to measure each indicator parameter of power quality monitoring, uses the Matlab software to simulate these algorithm to verify their correctness and reliability, andprograms by the C language, provides the foundation for power quality monitoring device. Finally, the paper summarizes the work of this paper and puts forward a number of issues needed to be further studied.