Research On Following Control Of Motor Current In EPS Based On Auto Code Generation

Compared with Hydraulic Power Steering,EPS has smaller space and Lower fuelconsumption.besides, EPS can reduce steering torque in low speed situation, preservesteering feels in high speed situation.In order to better use the function of EPS,the controllogic and Compensation should be better designed.For the reason of efficiency, Auto Code Generation is used. Some device driver modelsthat are compliant with the MC9S12XDP512chip which is used are created. The change ofcontrol logic can be achieved by adding、modifing、deleting module in EPS model,Code canbe generated automatically from EPS model.this method can save development time. Controlprocess is clear at a glance.The fixed PID control can’t meet better following controlof Motor current.When thetarget current is changing fast, Proportion should be high, Integral value should be zero.When the target current is changing fast, Proportion value should be low, Integral valueshould be high.We use control strategy of fuzzy self-adaptive PID to get the curve ofPID.According look-up table to implement the Variable PID control.In this way, Motorcurrent can follow target current better.The inertia of Steering system have major side effects on EPS system. Whendriver suddenly turns the steering wheel,they can feel the frustrated force.This feel is causedby the inertia of Steering system. The moment of steering system inertia is connect withangle acceleration,We can add compensation of angle acceleration to overcome theside effects of inertia. However,the signal of angle acceleration has noise.Test indicates,torque differentiation has correlation with the signal of angle acceleration. we usecompensate of torque differentiation to replace compensation of angle acceleration. Testindicates that this method can effectively overcome side effects of inertia.