Design Development And Application Research Of The Medium Voltage Min-Used Inverter

The shortage of power and energy has become one of the significant factors which restrict development of national economy, especially the main power consumers such as coal enterprises. It wasted the power resources seriously, and power consumption constituted a considerable proportion in its production costs. At present, the transformation for coal mine production devices with the frequency technology can achieve power saving, energy saving, and production efficiency improvement. Due to the use of 1140V special level voltage, the general 380V inverter can't be adopted in mining production; moreover, the relevant immaturity domestic market made it's significant to study on the medium voltage mine-used inverter and application research.According to 1140V special level voltage and the requirement for frequency control of motor speed based on special mine condition, the paper studied from the following aspects:1. Based on the prototype of 380V inverter, the research results, and the relevant references, the paper studied the control performance of the flux observer current model, voltage model, and voltage-current model, either at the low speed and high speed. These models were established to solve the problem of 380V inverter at the high speed. The results of simulation primary demonstrated that the hybrid model overcomes the shortcoming of single model, and it's better to control under voltage-current module both at the low and high speed.2. Considered the inverter was designed to drive conveyor belt, the viscoelasticity dynamic characteristics and starting characteristics of belt conveyor was studied; several ideal start curves were provided. The paper gave a model combined the model of motor driving by inverter with the dynamic model of conveyor belt. The simulation results of motor controlling by inverter with the load of normal constant torque and the special viscoelasticity load of conveyor belt were compared, the results showed that although the special load effect motor control, the variable frequency control effects of conveyor can be achieved.3. According to the debugging problems of the 380V inverter, the paper discussed the modification and improvement on design of hardware system, circuit and circuit board of 1140V inverter. Such measures can also enhance the robustness and anti-jamming performance of system.At last, based on the technology mentioned above, the prototype of medium voltage 1140V mine-used inverter was made. The experimental results of the inverter showed that the medium voltage frequency inverter could realize the function of motor variable frequency speed regulating.