Design Of Dynamic Reactive Power Compensation Device For Building Distribution

Nowadays,electric power technology develops rapidly.On the one hand,the existing equipment has more stringent requirements on accuracy and sensitivity.Meanwhile,clients require high grade and stable power supply.On the other hand,unbalanced and capricious load used by users will also reduce the power factor of the power network.As a result,the use of reactive power compensation devices to improve power quality and grid factors becomes more significant.The traditional reactive power compensation device has the problems of slow response speed and large power loss.In this paper,a static var generator that can realize accurate and fast compensation is selected as the research object,and a dynamic reactive power compensation device which can quickly reduce the phase difference between voltage and current is designed.This paper mainly studies reactive current detection as well as tracking compensation and DC side voltage control,then design a three-phase three-wire SVG system.This article mainly study the four matters as below:First of all,analyzes the current situation of the development of SVG device and its control strategy,with single phase equivalent circuit of the detailed analysis of the basic working principle of SVG,select voltage diode bridge type circuit design clamping type three level topology as SVG main topology structure,then design the reactive current based on instantaneous reactive power theory test as current test system.Secondly,design the overall system.The SVG system mainly includes sampling unit,conditioning unit,main control unit,SVG power module and peripheral circuit.Among them,the signal conditioning unit is used as the power data acquisition unit to obtain the power data information of the power grid.The main control unit adopts the ARM core architecture and is designed based on the STM32F407 IG chip.It analyzes the electricity data information obtained by the signal conditioning unit,and then sends a command to the current regulator(PWM)to control its pulse width modulation signal.The module mainly includes reactor,IGBT and current regulator,which is used for forward or reverse compensation of reactive power of the system.Then the system simulation model is built based on the power distribution load of the second laboratory building of the school in MATLAB/ Simulink.Through theanalysis of the simulation model,it can be seen that the voltage and current are basically synchronized,there is no phase difference,and the power factor has been significantly improved,and through changing the load type to verify the applicability of the system after switching SVG stable operation.Finally,the paper summarizes the work done,analyzes the limitations of the designed device and puts forward improvement strategies.In addition,the development prospect of the designed device is also prospected.