| Advanced Static Var Generator (ASVG) is an advanced dynamic var compensation equipment and an important device of the Flexible AC Transmission Systems (FACTS). It can control reactive power dynamically and flexibly to improve the reliability and enhance transmission ability of the power system. In the thesis, the principle and the control method, as well as the prototype of ASVG are proposed in detail which is supported by Hunan Science and Technology Projects.Firstly, the dynamic compensation principle of reactive power and the structure of ASVG are analyzed in the thesis. Then controlling and running characters of ASVG are researched. Compared with traditional var compensation equipments, ASVG has higher respond speed and wider regulation range, as well as other superior characters. Furthermore, the equivalent circuit and dynamic model of its main structure are built, with dynamic characteristics analyzing on a-b-c coordinate andαβcoordinate respectively. Above researches found a basis for control and realization.Secondly, the i d ? iq algorithm is adopted to detect the referenced currents, which is based on the instantaneous reactive power theory. Fuzzy-PI control method of ASVG is also put forward to improve the dynamic performance as well. Combining dynamic characteristics of Fuzzy-Control with respond speed of PI-Control, ASVG system not only has fast response, but also has satisfied control precision. Then methods can be realized easily by digital control and is verified by digital simulation. However, some harmonic voltages will be added because of dead-time effect in the pulse width modulation (PWM), so a better dead-time compensation method is applied after comparing.Finally, the prototype of±100KVar ASVG is proposed, including its inverter, snubber circuit and control system. The experimental results show good compensation effect of ASVG with proposed control system, such as reactive power balance and systematic power stability.
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