Development Of A 100kvar Parallel Hybrid Active Power Filter

With the development of modern technology, there are more and more nonlinear loads used in power system, that causes too much harmonic pollution, and the power quality becomes worse sharply. It is imperative to deal with harmonics under the situation.The Active Power Filter (APF) and conventional Passive Power Filter (PPF) both have disadvantages. But the Parallel Hybrid Active Power Filter (PHAPF) composed of them can have their advantages and eliminate their disadvantages. At the same time it possesses the characteristics of low price of PPF and good performance of APF. It can make harmonic compensation system reach the best performance at a lower cost, APF is being applied more and more extensively in home market. So it is practical to develop the PHAPF for deal with harmonics and reach the best performance at a lower cost.In allusion to the harmonic issue and the idea of harmonic restraint along with the development and actuality of PHAPF, this paper gives the system design scheme and frame of the swatch based on the basic work principle of PHAPF and various actual questions.At design the PPF, in view of practicality, a deep study was developed in these two fields: the distributing rule of industry load harmonic frequency compose and the proximity effect which have effect on the winding's AC loss . According to the study, we got a baseline of design for the capability distribution of passive network and reducing the winding's AC loss.The result offers a design gist for the capability distribution of passive network and a guide line on design which for reduce the winding's AC loss ultimately. At design the APF, emphasis on the convertor. And then the control circuits, including the main control circuit and logic circuit.In order to solve the problem of compensation equipment power balance, the study placed the emphasis on analyzing and desiging the DC voltage bus balance adjust system. At first, based on the DC bus balance adjust system of the swatch, mathematic control model was set up, which was used to analyze central parameters' select range of the steady system and fix on the select of PI adjustor. Then, the design of low pass filter in harmonic check tache was researched. Finally, a selection for capacitance capability of DC bus was decided according to the analysis of the DC bus balance model based on instantaneous reactive power theory combined with the practical system.In allusion to the stability problem of conventional closed loop control strategy, a mathematic model was set up in this study, which was used to analyse the stability of hybrid system. In order to solve the problem of overload under the voltage control strategy, a patent technology was introduced in this paper, with a analysis of the stability of system under the new method.Finally, experiments on the manufacture of PHAPF were developed. We got favorable effects on the sieve harmonics and transient according to the experiment. The DC bus voltage can maintain invariableness and the experiment can restrain overload.