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Large capacity based on repetitive control Shunt Active Power Filter several key technologies

Author: WangZhiQiang
Tutor: ChenGuoZhu
School: Zhejiang University
Course: Power Electronics and Power Drives
Keywords: Shunt Active Power Filter Plane bus LCL filter Repetitive Control PI control
CLC: TN713.8
Type: Master's thesis
Year: 2010
Downloads: 319
Quote: 5
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Abstract

Large-capacity industrial applications shunt active power filter is controlled normally controlled harmonic current sources, ideal for compensating large power system harmonic current-source, so its main circuit design and control methods of research has important theoretical and practical engineering significance. In this paper, based on repetitive control 260kVA three-phase three-wire shunt active power filter industrial prototype of its several key technical problems were investigated. Power inverter main circuit switch distributed inductance for the safe and efficient work is essential. This paper analyzes the reduction equivalent distributed inductance laminated bus plane, based on the design of a large-capacity inverter for non-inductive planar busbar structure, greatly reducing power device switching voltage spikes and EMI problems. LCL filter its better filtering performance gradually be applied to a large-capacity shunt active filter device, but because it contains a number of parameters and difficult to design. This drop in the key consideration filter inductor, filter capacitor reactive power, high-frequency shunt effect, the resonant frequency factors based on the parameters of an LCL filter design methods. The method is simple, clear physical meaning, has a certain value in engineering applications. Thermal structure directly related to the large-capacity power electronic devices are long-term reliable operation. However, with multiple heating elements and the heat-sensitive device, the thermal design becomes complicated. This paper proposes a cooling duct isolated structure, which through independent and compact power modules ensure duct cooling effect, while the harmonization of the main cooling circuit passive components, which greatly reduces the number and size of the device fan . Large-capacity shunt active power filter compensation accuracy depends on the current loop design. Since the current loop reference and feedback current harmonic superposition of many traditional PI regulator steady state tracking performance is poor. This paper presents a PI inner ring, outer ring consisting of repetitive control bicyclic compound control strategy is used to improve the output current waveform, and gives a detailed design approach. The controller on the odd, even harmonic currents and unbalanced load conditions negative sequence harmonic currents are compensated with high steady-state accuracy, while ensuring that the system dynamic response speed, and easy to implement. Start, and switching network and load the dynamic process, the DC bus voltage will generate significant overshoot or drop, a serious threat to the safety switching device, so the dynamic process of the DC bus voltage control is necessary. This paper presents a soft start and grid impact suppression techniques to solve during startup and the DC voltage grid volatility issue. Then the AC side and DC side power balance equations, derived voltage loop of the small signal model. Finally, based on this model, a high dynamic performance of the DC voltage regulator.

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CLC: > Industrial Technology > Radio electronics, telecommunications technology > Basic electronic circuits > Filtering techniques,the filter > Active filter
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