EVT Hybrid Powertrain Control System And Experimentaltest Bench Research

Compared to conventional vehicle, hybrid electric vehicle(HEV) significanlyimprove fuel economy and realize energy saving and emission reduction. Meanwhile,HEV which bring an internal combustion engine and less batteries also extend thedriving range compared to electric vehicle. Since a HEV is equiped with more thanone power machine, a special energy converter is needed in its powertrain. Electricvariable transmission(EVT), as a new kind of energy converter which has dualmechanical ports and dual electric ports and can realize multiple-directiion energyflow, seems to be an execllent choice for HEV powertrain.This thesis is focus on the EVT based HEV powertrain control system.A relative angular position/speed sensor is put forward to solve the angularpostion/speed measuring problem for dual-rotor-machine. For implementing vectorcontrol especially torque control on the key component of EVT, dual-rotor-machine,it is necessary to acquire the relative angular position/speed signal. So a mesurementwhich can detect angular difference between two different shaft is designed based onall-digital-resolve-to-digital algorithm. The mesurment is proved to be feasible andcorrect by simulaiton and experiment.Pointed at the multiple-direction energy flow, the control problem of EVTbased HEV powertrain is analyzed. Firstly the control way of EVT power machinesis decided, then the operating modes of EVT powertrain is analyzed. Secondly,based on the power following control strategy, aiming at following the powertraindemanded torque, the EVT based HEV powertrain control strategy is designed, andthe dynamic control is realized.For emulating the real driving condition on test bench to evaluate theperformance of EVT powertrain and making it convenient to design complicatecontrol strategy, dynamic load emulation platform should be built for EVTpowertrain. According to the driving resistance, a vehicle load emulation system isdesigned. Combined with the strategy put forward before, EVT dynamic experimentis finished.