Output control of an auxiliary power unit of series hybrid electric vehicle

It is discussed that power is controlled from the auxiliary power unit (APU) and the traction battery package (TBP) in the series hybrid electric vehicle. The three methods of voltage, current, and power control of the APU are analyzed on the equivalent circuit in this paper. And a speed-level power follower algorithm is presented. All these are done on the dSPACE prototype controller. Both the diesel engine speed and the excitation current of the brushless AC synchronous generator are regulated. Experiment results validate the three algorithms right. It is most diffcult to hybrid power from the APU and TBP for the voltage control. Both the engine speed and generator torque are decoupled by the speed-level power follower, which makes the load powered freely by the APU, the TBP, and both of them respectively.