| APF(Active Power Filter) has excellent performance in itself such as dynamic tracking compensation, comprehensive solving power quality problems etc, however, the much larger installation capacity for APF and much stricter demands of components, and thus the much lower efficiency for pure APF in large capacity and load changes suddenly situations for compensating harmonic and reactive power simultaneously. In addition, its relatively high cost and quite complicated design limit its wider application. Power quality problems must be resolved urgently but the reality is all cases are limited in our country, and so generalized reactive power compensation device whose topology is APF in parallel with TSC (Thyristor Switched Capacitor) can fully play the advantages of APF in harmonic restraining effectively and TSC in large capacity having the advantages of low cost invest, small capacity of APF and with a comprehensive solution to complex or mixed power quality problems and so on.Facing with the existing problems and technical conundrums existed in generalized reactive power compensation device, the article takes "key technologies of generalized reactive power compensation device" as its basic research objects focusing on key technologies such as harmonic and reactive current detecting methods, control schemes, and algorithm realization based on simulation model, and the design of control system based on theoretical and simulation studies, and so conclusions are educed preliminarily. Mainly research works are as follows:Firstly, this article focuses on detection methods for harmonics and reactive current of the device. In view of the existing problems such as complexity of realization, large amount of computation, and cannot detect fundamental reactive current transiently under any load conditions, optimized dq0 algorithm is proposed embarked from dq0 transformation. Application of the algorithm can obtain active and reactive current through a transformation, which can reduce the calculation and improve real-time response capabilities; transient fundamental reactive current detection algorithm is proposed for any load condition based on optimized dq0 algorithm, having the advantages of small amount of calculation, easy to be implemented, and cannot requiring phase information of fundamental voltage; Respective-order filtering detection on the basis of above theories is studied to bring forward a novel way making device multi-functions. Finally, simulation analyses on the above studies are carried out to validate its accuracy and real-time response.Secondly, this article analyses control schemes of generalized reactive power compensation device in-depth. Optimized control scheme on sine-triangle compare control method and reactive power control strategy compositing by voltage and reactive power based on the study of the principles and characteristics of control algorithms. System voltage and DC voltage are introduced into optimized control algorithm as the feedback input signal to eliminate its disturbance on compensation effect to greatly improving compensation effect, anti-interference ability and stability of the device; finally simulation experiments are carried out to analyze and validate above contents.Thirdly, circuit design of each module of generalized reactive power compensation device is carried out. Configuration methods of all parameters of each module are introduced through theoretical analysis, and thus simulation model is designed to verify its effectiveness and overall performance of the optimized algorithm.Finally, control system is designed preliminarily to realize the functions of generalized reactive power compensation device. Integrated and multi-functional terminal is designed based on OMAP platform through theoretical study and simulation experiment, and the principles of hardware circuit are given to realize its primary functions and flow charts of key partial functions building a solid foundation for next applications of the device.
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