Research On Design And Optinization Of Control Strategy For Integrated Starter And Generator System Of Motorcycle

Currently,the motorcycle starter system in China consists of a starter motor and mechanical transmission mechanism,lacking a motor controller to achieve intelligent start-stop function.In addition,the power generation system is composed of a generator and rectifier,separated from the starting system,requiring more components and higher costs.With the promotion of the future National V emission standard,motorcycles must have intelligent start-stop function to further reduce emissions.Therefore,replacing traditional starter motors and generators with Integrated Starter and Generator(ISG)has become an inevitable trend in the motorcycle industry.The thesis aims to design and optimize the control strategy of the motorcycle integrated starter and generator system,and apply it to the motorcycle ISG to achieve fast starting and precise power generation voltage control functions.At the same time,by communicating via CAN between the ISG controller and the motorcycle ECU,the motorcycle can have intelligent start-stop function to meet the National V emission standard.The main research contents of this thesis are as follows:Firstly,this thesis studies the traditional overall control strategy of motorcycles,combines with the requirements of motorcycle manufacturer,designs the overall control strategy of the ISG system using state machine model,and optimizes the state transition conditions and abnormal protection function,improving the robustness and safety of the control strategy.Secondly,to meet the motorcycle manufacturer’s requirements for motorcycle starting performance,this thesis redesigns the motorcycle starting process,combining the engine reverse positioning process with the shutdown process,so that the engine is already in the optimal position before the next start,greatly reducing the starting time.At the same time,based on the motorcycle starting process,a ramp voltage soft start current limiting strategy based on speed design is proposed to reduce the impact of starting large current on the back-end circuit;for the motorcycle shutdown process,a motorcycle engine reverse positioning strategy based on Hall sensor is proposed,which makes the engine quickly and accurately stop at the easiest start-up position after each shutdown,so that the motorcycle starting success rate reaches 99.7%,and the starting time is less than 0.5seconds.Then,this thesis studies the power generation control strategy of the motorcycle integrated starter and generator system,improves the six-step voltage vector phase-shift control strategy,and combines with PID control algorithm to achieve voltage stabilization and current limiting output during power generation,improving the stability of the generated voltage.Finally,based on the above control strategies,this thesis designs the complete control program of the motorcycle Integrated Starter and Generator system,and conducts experimental verification and optimization on the motorcycle test platform.The experimental results show that the designed and optimized control strategies in this article meet the motorcycle manufacturer’s requirements for starting speed,starting success rate,power generation stability,reliability,robustness,and safety,and have passed the motorcycle manufacturer’s functional testing and durability testing.These test results have important significance for the development and application of motorcycle integrated starter and generator technology.