Design And Analysis Of Dry-type Magnetic-valve Controllable Reactor

In power system, reactive compensation and reactive balance is essential for increasing the economic efficiency of the whole power network and improving the quality of power supply. Therefore, the development and application of novel reactive compensation device has obviously become an important research topic in power system.In recent years, the novel reactive compensation device develops rapidly, and its type is also increasing. The existing novel reactive compensation devices in the power network mainly include synchronous condenser, thyristor switched capacitor(TSC), thyristor controlled reactor(TCR), STATCOM, etc. Synchronous condenser has been rarely used because of its slow response speed, difficulty of maintenance and many other shortcomings. TSC can not realize the continuously reactive power regulation. TCR has advantages of fast response and flexible control, but due to the limitation of its thyristor voltage level, the application in high voltage-high power situation is limited. And in the process of the work, TCR will produce a lot of harmonic current, so we need to install the filter device. STATCOM has advantages of fast response, flexible control and small footprint, but it has not been widely used in the ultra high-voltage grid because of its high price and difficulty of maintenance.As a novel reactive compensation device, Magnetic-valve Controllable Reactor (MCR) could adjust its reactive capacity smoothly with the changing of the saturated degree of the core by regulating the DC excitation. This kind of controllable reactor has a lot of advantages, such as wide voltage range, fast respond speed, low harmonic content. For improving the transmission capacity of power network, regulating the power network voltage, compensating the reactive power, limiting the operating over-voltage, it has a unique application potential.Firstly, this paper outlines the development history, research situation and application prospect of MCR, then briefly describes the basic structure, working principle and mathematical model of MCR. Meanwhile, it points out many unique advantages of MCR.Secondly, this paper provides the design calculation formulas of MCR, and derives the analytical expression of the operating current in different saturation level, then analyzes the impact of magnetic valve parameter on the operating current total harmonics distortion by using Matlab program.Thirdly, this paper builds a 2D finite element model of the lOkV MCR by using Ansoft, and analyzes the AC winding current harmonic content under different working conditions, this current harmonic content is identical with the calculation results in analytical method.Finally, this paper develops a MCR design software based on Matlab GUI. This design software combines parameter setting, calculation and simulation together as a whole, its software interface is friendly. What’s more, it can realize the analysis of the operating current harmonics, and its design accuracy can meet the engineering requirements.This paper will provide a solid foundation for the design of MCR.