Research On Position Sensorless Control Systems For Switched Reluctance Motor

Switched reluctance motor has many advantages, such as simple and strong structure, high efficiency and reliability, so it has been used in many industrial systems. When switched reluctance motor works, the logical switch of each switch devices are decided by the position of rotor. In order to detect the position signal of rotor, we need to install the mechanical position sensor in the non-output side. Due to the limitations of the position sensor working under the harsh conditions, the detected position signal is inaccurate. What’s more, the position sensor increases the costs and the volume of switched reluctance motor. Therefore, the technology of position sensorless control for switched reluctance motor becomes one of the focused problems in electrical drive field.First of all, this thesis introduces the development history and advantages of switched reluctance motor, then it narrates the operation principle of motor. According to the flux characteristics of switched reluctance motor, the flux linkage, current and rotor position angle have the nonlinear mapping relationship between them, so a kind of rotor position detection technology based on the echo state network is proposed. This method takes voltage, current, and flux linkage as the inputs of network, meanwhile it takes the corresponding rotor position as the output of network. Then the trained echo state network is used to replace the mechanical position sensor to realize the position detection of rotor.In order to demonstrate the validity and reliability of the proposed method, the author takes a5kW three-phase12/8pole motor as the research object, and takes TMS320F28335as the control chip, then designs a digital control system of switched reluctance motor which includes the control circuits, the current sample circuits and the power drive circuits, etc. Then this thesis expounds in detail on the digital implementation algorithm for the data sample, the network training, the PI regulator and the calculation for the speed. After that, the logic switch is designed in light of the operation principle of motor, and this systems realize online operation for rotor position detection.The experimental results indicate that the control system can better meet the design requirements, and the position detection technology based on echo state network can detect the rotor position accurately, and realize the position sensorless control for switched reluctance motor.