Research On Intelligent High Voltage TSC Reaction Power Compensator

With the quick development of national economy and the rapid increase of power system load, all kinds of power load such as low power factor load, rectifier load, impact load access power network, bring so much power quality problems as low power factor, high-order harmonic pollution, waveform distortion of voltage and current. In order to solve the above problems of power quality, it is necessary to install the reactive power compensation devices in power system. Thyristor Switch Capacitor (TSC) is a widely used device and have high performance-cost ratio in many reactive power compensation devices. It plays an irreplaceable role in regulated voltage, improve electric power factor, ensure the quality of power supply and improve power quality, especially when the power network voltage is 6KV～35KV.Based on the study of TSC reactive power compensation device's working principle and capacitor switching without inrush current, a whole set of intelligent high-voltage TSC reactive power compensation device is designed in this thesis. In the terms of hardware circuit, Digital Signal Processor TMS320F2812 is used as core processor which produced by Texas Instruments Company. Anti-jamming signal sampling circuit, dynamic protects circuit and convenient human-machine interface circuit is also designed. Three-phase thyristor valves connection mode is given which is based on 10KV power transmission system. The key technology of thyristor series' drive system--photoelectric trigger system is analyzed emphatically. In this photoelectric trigger system, the isolation of trigger circuits between high voltage and low voltage are solved by high insulation of photoelectric converter circuit. The power supplies circuits of thyristor series'high voltage driver are also isolated from one another, and this design is original, simple and efficient. So the consistency of thyristor valve conduction can be realized reliably. In the terms of software, the structure diagram and capacitor switching control criterion is given. The voltage and reactive power compound control criterion is applied in the device, it use reactive power as main criterion and voltage as auxiliary criterion, switching oscillation can be avoided under light load. Considering the reactive power compensation environments of different capacitor voltage, corresponding switching control schemes are proposed. So the device can be applied to any environments which need frequent switching capacitor quickly.Finally, a real TSC reactive power compensation device is tested in low voltage power network and high voltage power network, the experimental results show that the device is effective and reliable, the capacitor can be frequent and fast switched without inrush current, and the device is also satisfied the requirement of electric power system.