TCR+FC Type Reactive Power Compensation Technology In Mine Hoist System

Mine hoist is a high-power and high energy consuming facility which is widely used in many mining companies. Mine hoist system broadly employs the rectifier made of power electronic devices in managing the power supply of its DC motor. The constant opening and closing of the hoist in the process of mining often causes reactive power shock and harmonic pollution, which greatly affects the safety and stability of the power supply for the grid and leads to more failures and shortens the life of the hoist system and related equipments. At the same time, lower power factor can’t make full use of power energy and a large amount of energy is wasted. This study is going to carry on a corresponding research in the regards of reactive power compensation and harmonic management technology according to the hoist system characteristics,It is of great significance in improving the power supply of the grid and ensuring the safety, stability and high-efficiency of the mine.Firstly, the subject of this thesis is focusing on the hoist system of one Chinese lead and zinc mine. Through the deep analysis of its characteristics of the power supply system and the related data of the power energy index, the thesis proposes a method combined with TCR(Thyristor Controlled Reactors) and FC(Fixed Capacitors) to deal with reactive power compensation and harmonic management towards the cases of reactive power, power factor and harmonics produced by the rectifier in the operation of the hoist. Secondly, this thesis makes proposals for the reactive power compensation device of the hoist system in terms of a new design of its circuit structure, its parameter calculation and its universal optimizing method. At last, focusing on the particularities and complexities of the mine hoist, this thesis comes up with a control calculating method based on the closed loop PI to realize controlling the reactive power device. By means of combining the power supply structure and its parameters with the reactive power compensation device and building a corresponding simulation circuit in MATLAB, the device will check the feasibility and reliability of this system according to the simulation results. And it will make some adjustments to its parameters which will reduce the adjustment task in later time.Via testing and analyzing the index of power factor, three-phase voltage and harmonic content of the mine hoist system when in the operation of reactive power compensation device, it is proven that the TCR+FC type reactive power compensation and harmonic management device has a noticeable effect in stabilizing the system voltage, improving power factor and reduce harmonic content as proposed by this thesis. Besides, this thesis has made some suggestions on improving the circuit structure design of the reactive power compensation device, control system design and the calculation and optimization of the parameter for the mine hoist system, which will offer some reference and guidance for the project research and design of the reactive power compensation device to some degree and will benefits the task of energy saving and emission reduction for the mining company. Figures(35), Tables(6), References(65).