Research And Design Of Vehicle Electrical System For Remote Control Excavator Of Decommissioning Nuclear Facilities

In the process of decommissioning of nuclear facilities,we need construction machinery for decommissioning operation.For this kind of problem,this paper designs the electric control system of the nuclear decommissioning remote control excavator based on the small excavator.The equipment is equipped with a manual and remote control mode.In the remote control mode,the operator can effectively realize the work of the radiation protection excavator in the safe area away from the nuclear radiation.In manual mode,the operator completes the job by controlling the steering mechanism in the radiation-proof cockpit.Nuclear Facility Decommissioning remote-controlled excavator protects the workers from radiation threat and improves the efficiency of the decommissioning and disposal of nuclear facilities.The contents of this study are as follows:(1)According to the overall structure and operation rule of the excavator,the overall design scheme of the vehicle electric system is put forward according to the function demand of Nuclear Facility Decommissioning remote-controlled excavator.(2)We focus on key issues and make full preparations for follow-up on-board electrical system design.1.According to the actual work situation,taking into account the defects of the traditional PID algorithm,we proposed digital PID algorithm with an incremental limit and dead zone,to achieve stable control of the engine throttle motor system.2.Study the influence of PWM drive technology on the electro-hydraulic proportional valve.According to the proportional valve coil circuit model,the duty cycle is linear with the average current of the coil within a certain range when the frequency is certain;The influence of the working temperature of the proportional valve coil on the control current is studied.In order to stabilize the control current,an incremental PID algorithm is used to adjust the duty cycle to offset the current change.(3)We designed the vehicle hardware and software control system.The vehicle electrical control system takes two controllers EPEC2024 as the core and realizes data communication through CAN bus.The controller receives control instructions.The control functions include:Realize the starting or extinguishing function of the engine;Adjust the power output of the engine;According to the control instructions of the remote control,the secondary output pressure of the electro-hydraulic proportional pressure reducing valve is controlled so as to change the direction and the opening area of the main reversing valve,then control the hydraulic device to complete the excavator operation;At the same time,the controller collects the water temperature of the water tank,engine speed,fuel quantity,pressure sensor and other sensor signals,and sends the system work data to the remote control device to display.The performance of hardware and software is tested on existing excavators.The test results show that the software and hardware design of the vehicle system meets the requirements.