Enterprise Supply System Active Power Filter Technology Research And Engineering Applications

The involved project is funded by National Science-Tech Tackle Key Project, "Research on Active Power Filter for Power Harmonic Eliminating" (NO.2002BA218C) and Hunan Power Corp. Science-Tech Tackle Key Project, "Research on Engineering Application of Power Harmonic Eliminating" (No. [2001]772). Taking the harmonic attenuation of the 10KV power distribution network at the 110KV substation in a smeltery as object of study, this dissertation aims to do research on the control strategies and its industrial application technologies for eliminating harmonic in medium and high voltage power network. The production of the project is listed as one of the new important products in China[2003ED770013].Firstly, after the comparison of the existing active filters, a Novel Series Connected APF and PF is analyzed deeply here to meet the given situation of substation harmoinc elimination. Then harmonic detection method using ip,iq algorithm, which is based on the instantaneous power theory proposed by H.Akagi, is introduced briefly and is extended to detect positive or negative sequence of arbitrary order harmonic in single-phase system, three-phase three-wire system or three-phase four-wire system.. Because there is the time delay in the digital controller inAPF system. Based on extended ip,iq algorithm, a new algorithm adding the compensatory angle for random harmonic current detection of active power filter is proposed. This algorithm can overcome the infection of the digital controller's delay time to harmonic compensation and realize the real time compensation. Analyses and simulation prove the correctness of the algorithm.The analysis of state of arts of acive filter control is performed in this dissertation from the point of view of classic control theory. Generalized integrator based iterative control algorithm is proposed. Period information of system is added to the control strategy to realize none steady error, ensuring the excellent performance of NSCAP. Past control variable information is fully used in generalized integrator based iterative control algorithm which simplifies the calculation. This controller is easy to realize and provides excellent performance with fast responds. In additon, ripple components at high frequency in power source currentare small enough to neglect because the switching harmonics are easy to eliminate under the discrete ternary variable-structure controller proposed here. Simulation and experimental results confirm its effectivity.In the end, industrial application technology was researched. Parameter designing rules of the main components were discussed in detail. In the last part of the dissertation, the typical experimental results were presented. This system helps to the improvement of power quality and the management of power system harmonic.