Research On Multi-Power Robust Coordinated Control Of Electro-Mechanical Transmission(EMT) System

Hybrid vehicles,with high efficiency and strong power output is superior to the advantages of traditional vehicles,as a result,it is widespread concerned by the domestic and international scientific research areas.The transmission system is one of its core components,and it can be called the electro-mechanical transmission(EMT)system.The system has the function features of series and parallel structure system,which can improve the performance of the system.This paper will focus on electro-mechanical transmission system to carry out research on the multi-power coordination control issues.Firstly,in order to ensure the normal operation of the system,and provide convenient environment to carry on the thorough research to the coordinated control strategy.The system control development platform is constructed.The integrated control strategy of the electro-mechanical transmission system is proposed,including the rule-based energy management strategy based on the expert PID control strategy.The rule-based energy management strategy is responsible for obtainning the optimal state point of the system;the coordinated control strategy is responsible for coordinating the operation of various components to track the optimal state point.Secondly,according to the robust control method used in the dynamic coordination control,the modeling requirements of the system model are clarified.The dynamic response of the model is improved by identifying the key components of the system(engine and motor).The model set is used to deal with the uncertainties in the modeling process,and the system model set is obtained.Standardizing the system model set with the fractional transformation method,and obtains a set of standard models with uncertainties that can be applied to the controller design.Thirdly,the characteristic of the system mathematical model is analyzed,and the dynamic coordination control problem is formulated as a servo control problem of multiple input multiple output(MIMO)system.The frequency and bandwidth of the system are calculated,and the frequency-weighted method is used to build the augmented system with constraints and performance requirements.The singular va lue of the structure with uncertain system is minimized and the D-K iterative method is used to solve the problem,then a robust coordination controller can be solved.The controller can resist the disturbance of uncertainties for the system model set.Then,according to the problem that the order of the model and the controller is too high,the Hankel singular value of the system equilibrium can be used to judge the dominant state number of the system.Based on this,the linear matrix inequality(LMI)method is used to reduce the order,and a low-order controller is obtained,which is validated by the simulation of the cycle condition.Finally,on the bench of the low power test bed,the simplified control loop condition is used to test the coordinated control strategy,and the effectiveness of the coordinated control strategy is verified.