Research On Loading Robust Performance Optimization Of PWM Rectifier In Oil Well And Development Of Measurement And Control System

Oil well mutual feed-through and energy saving structure has been applied more and more widely in oil exploitation industry.Because the oil well group control system is a typical stray system,the interaction between the large range fluctuation of load up and down strokes and the common direct current bus is discrete.On the one hand,using traditional based on proportional integral(PI)controller general rectifying device in rectifier,hard to avoid due to the improper operation of group control Wells renewable electricity cannot be fully absorbed,or the group control of some oil Wells in oil Wells lightening downtime caused by the load fluctuation,the dc bus voltage fluctuation or rising phenomenon occurs,resulting in protection misoperation or equipment damage.On the other hand,from oil well environment,it is susceptible to various disturbances and system uncertainties.For example,the input voltage fluctuation and circuit parameter perturbation will reduce the working efficiency and output voltage quality of the rectifier device,so that the performance of the oil well PWM rectifier device is severely tested.Therefore,this paper focuses on the research of the optimal control method and technology of the load robustness of PWM rectifying device,and develops the research results and applies them to the embedded rectifying measurement and control system.Firstly,the working principle of PWM rectifier is analyzed,and its mathematical model is deduced.The structure and algorithm of the linear active disturbance rejection controller are analyzed.Because the load disturbance has a great influence on the voltage outer loop,the linear active disturbance rejection control strategy based on the reduced order extended state observer is adopted in the voltage outer loop of the PWM rectifier device.The controlled quantity and the disturbance quantity are estimated by the observer,the disturbance quantity is compensated by the feedforward channel,and the proportional controller is designed to control the controlled quantity,so as to improve the tracking speed when the controlled quantity changes.Secondly,the outer voltage loop active disturbance rejection control and the inner current loop traditional PI control are adopted in MATLAB /Simulink.The spatial voltage vector modulation(SVPWM)technology is selected to establish the mathematical model of the three-phase voltage type PWM rectifier device.The operation conditions under load step change,load wide range change and power grid fluctuation were simulated respectively.The control effects of proportional integral control and ADRC control rectifier devices under rectification and inverter conditions were studied.The load robustness of the two rectifier devices was compared and analyzed.At last,this paper develops the rectifier device for the oil well energy mutual feed and energy saving production system with TMS320F28335 as the controller core.Based on the immunity control voltage outer loop,and nonlinear decoupling direct current double closed loop control strategy of the inner ring,designed a data acquisition and processing,DSP control system and hardware circuit such as signal driver finished the DSP control program and the underlying driver program are developed,and the simulation load test and performance analysis are carried out under the oil well condition.The results show that,the DC bus voltage of the rectifier device in this paper is more stable under load fluctuation and disturbance,and the load robustness is effectively improved,which provides technical guidance for the implementation of energy saving production in oil fields.