Research On The Safe Operation Controller Of High Power Asynchronous Motor

There are a big impact current and torque when asynchronous motor of hydraulic station starts directly.It would bring great impact on a power system,and cause a water hammer effect,when it stop,there also exist the water hammer effect.When the high power runs,it would bring make diagnosis of faults such as overload,over-voltage,under-voltage.In order to overcome these problems,a safe operation controller is designed for the high power aschronous motor.It can decrease the starting current and restrain the water hammer effect in starting and stopping,diagnosis the faults of the high power aschronous motor itself,it also provide the excellent anti-disturbing ability and stability in the strong electromagnetic interference.The main research contents as follows:First,a new soft start control strategy of variable universe fuzzy control adaptive fuzzy control for the high power asynchronous motor is proposed.For the system of soft start control of high power asynchronous motor is a time-varying and nonlinear high level system,mathematical model of high power asynchronous motor is analyzed.The defects of conventional fuzzy logic control and variable universe fuzzy control based on function model applications in engineering is analyzed,and a new variable universe adaptive fuzzy control method is applied to high power asynchronous motor.The simulation model of soft start in Matlab/Simulink is established,the simulation result of the new adaptive fuzzy controller based on variable universe is provided and it compares to the methods of traditional PID control and conventional fuzzy logic control.The simulation result shows that application of this method to soft start is effective,it brings advantages such as no need for exact models,fast response,and high precision and strong robustness,and it is superior to other two.Second,the soft stop control strategy is established.As the load of the high power asynchronous motor,hydranlic pump always bring the water hammer effect.The traditional soft stop based on voltage ramp control cannot solve the water hammer effect completely,and the surges still exists.The soft stop based on power closed-loop control can solve the water hammer effect more effectively,and eliminate the surges and noise of the hydraulic system.Third,the running states of the high power asynchronous motor are monitored and its common faults are diagnosed.Fourth,the hardware system based on DSP of the safe operation controller is designed.The working conditions of the electromagnetic interference are considered. And the anti-disturbing ability is improved by taking use of good anti-disturbing measures.Fifth,the software system of the safe operation controller is designed,and the embedded operation system UC/OS-â…¡is transplanted to the safety controller.The UC/OS-â…±can manage effetely the software and hardware,therefore the safety and the stability are improved.