Research On The Switching Device In Independent Operation For Bus Of Coal Mine Power Grid

At present, Coal mine35KV/6KV substations Bus Operation using the power supply mode respectively. When the power into the line or transformer in maintenance, the6KV Bus Operation mode will be change from independent operation to parallel operation by switching operation. This kind of transformation process of bus operation mode can lead to power transfer lines appearing long time power outages. To such a special power supply system in the coal mine, this long time power outage question will be serious influence power coal mine production efficiency. Therefore, this paper presents a device that can directly operate with charged between two bus independent——the controller of switching device(TCSD).Because of the directly switching with charged between the two independently bus will inevitably cause circulation problems, so the main purpose of the controller of switching device is to suppress or eliminate the circulation. And the circulation size is relevant to the parameters of the two bus (on both sides of the voltage value, on both sides of the phase angle, on both sides of the system voltage frequency). And Flexible Alternating Current Transmission Systems (FACTS) can solve this problem. Therefore, this paper first studied the three typical FACTS control device. There are Static Synchronous Compensator (STATCOM), Static Synchronous series compensator (SSSC) and Unified Power Flow Controller (UPFC). Through the analysis of the topology of the SSSC device and control mode, it was proved to be similar with this paper put forward the controller of switching device. And it as a reference, this paper puts forward the topological structure and research the output voltage vector of the topological structure. Here, the main task of controller device is to output a voltage vector, and the voltage vector is the difference between the voltage vectors. So, the outputs of switching device should be divided into output amplitude of control and phase angle of control. Space voltage vector pulse width modulation (SVPWM) technology is used in motor speed on the magnetic chain algorithm of trajectory tracking. The algorithm has high efficiency DC voltage, low harmonic output characteristics, which are used as the control device of the PWM control algorithm. Finally in order to verify the control device can solve the problem of directly charged turn off the switch between the two bus independent operations, in MATLAB simulation tool SIMULINK environment, the topology of the entire system was simulated. Through the simulation analysis and proved that this paper puts forward the topological structure of switching device is correct and feasible. The last, this paper also has a hardware implementation for the testing part to the whole switching device. The ATmage128microcontroller as a main control chip, and on both sides of the bus parameters were measured. In order to facilitate observation, record and control related parameters, this paper also developed a liquid crystal display (LCD) touch screen, and we can direct observe or record or set the related parameters on the screen and so on. It has a good human-machine interface.