Research On Automatic Control Strategy And Technology Of The Electric Chassis Of The HV Switchgear

Economic development,electric power first.High voltage switchgear is part of the key devices to achieve the goal of building strong smart substations.It plays a major role in power system,such as interrupting line and relay protection.Its operational state has a direct impact on the reliability of the power system.As a main breaker of the high voltage switchgear,the circuit breaker chassis vehicle often appears motor block and even the chassis car is out of control and damages the contact of the circuit breaker when moving from the test position to the working position.With the rapid development of microelectronic technology,sensor technology and automatic control technology,the automatic control technology of electric chassis vehicle in high voltage switchgear is studied.A set of control device of high voltage switches cabinet electric chassis car is designed.First,the paper introduces the basic structure of electric chassis vehicle,and emphatically analyzes the mathematical model and equivalent circuit model of permanent magnet DC motor,so as to lay a theoretical foundation for the electric chassis vehicle control device to achieve the functions of electric control and locked rotor protection.In the MATLAB/Simulink simulation platform to verify the basis,determine the control device to form double loop control scheme with variable universe Fuzzy-PID control strategy based on control algorithm,response speed and stability of permanent magnet DC motor to maximize,minimize the interference of overshoot,shock and electromagnetic environment.Then,a motor control circuit based on PWM and IGBT module is designed.It can adjust speed according to the preset speed of entry and exit,and position signal of chassis,avoiding bad contact and contact overshoot of circuit breaker contacts.In order to solve the problem of motor starting and running card locked rotor,according to the permanent magnet DC motor stall fault conditions in overload and temperature rise model established by the relationship between the protection threshold of 6~9 times the running current setting range,and through the hall current sensor to collect motor current value to realize locked rotor protection.In the stall current data processing,this paper using Daubechies6 wavelet denoting algorithm based on the current signal decomposition,fast feature extraction in strong noise background by wavelet packet reconstruction,and locked rotor the immediate execution of protection operation when it is greater than the threshold to protect and prevent the motor running in strong noise the harsh electromagnetic environment.In addition,this paper uses 5 inch resistive touch LCD screen DGUS and RS-485 communication interface and remote control device on the spot,and display a circuit diagram,the running state of the equipment and the feedback parameter,intelligent integrated display provides monitoring information more intuitive and convenient for the staff.Finally,this paper sets up an experimental platform to test the functions of electric chassis control device,such as electric control,locked rotor protection,communication and human-computer interaction.The experimental data show that the reliability of the control device is superior,the response of the plug protection is rapid,and the expected design target has been reached.