Zhenhua Jin

Design and implementation of a real-time power management strategy for a parallel hybrid electric bus

A real-time energy management strategy derived from an equivalent consumption minimization strategy for a parallel hybrid electric bus is introduced. Although an equivalent consumption minimization strategy is a near-optimal control strategy for the power management problems of hybrid electric vehicles, the computation cost and the driveability requirements are still barriers for it to be directly implemented on real-time controllers. This paper analyses the controller characteristics of the equivalent consumption minimization strategy based on the Willans line model for an internal-combustion engine and an electric motor. A two-step method is proposed to simplify and approximate the standard equivalent consumption minimization strategy controller. The strategy for the proposed controller, which is called the Willans line–equivalent consumption minimization strategy, can reduce the computation cost of optimization and can guarantee near-optimum fuel economy, while improving the vehicle driveability. The proposed controller is then validated by offline simulation and an onboard bench test. A backward simulation is conducted to test the fuel economy performance of the controller simplified from the two steps, together with dynamic programming and an equivalent consumption minimization strategy based on look-up tables. Then the controller is tuned by a high-fidelity forward simulation to explore the trade-off between the fuel economy and the driveability. Finally, a bench test with real powertrain components is presented to illustrate the effectiveness of the proposed methodology.

Development of HIL test platform based on veristand for hybrid powertrain controller

HIL test platform based on VeriStand is developed for hybrid powertrain controller test. The hardware is constructed with PXI, which is connected with Hybrid Control Unit (HCU) through I/O and CAN cards. The vehicle model and driver model are built in Matlab/Simulink. VeriStand is adopted to manage models and test flow. HIL test during driving cycle and fault mode is presented. Application of HIL test platform shows it can meet requirements of HCU test.

Design and application of parallel hybrid vehicle simulation platform

A parallel type hybrid-electric bus model is constructed to study hybrid powertrain and its sub-systems. The model is a forward-looking model based on LabVIEW simulation module. The engine, clutch and battery model were specially designed according to the target powertrain. Each part of the model is separately validated by test bench experiment. Part model behavior is compared with that of real target part on dynamic testbed and revised if it was inaccurate. First, offline simulation was adopted to validate rationality and accuracy of the part model. Then, the model was downloaded into a real-time target PC running LabVIEW real-time operation system to study the control strategy of hybrid control unit. Control strategy was studied under three different driving cycles: New York Bus Cycle, Manhattan Cycle, and China City Cycle. The simulation results show that the hybrid-electric bus with good control strategy can improve fuel economy and reduce exhaust emissions.

Development and application of fuel cell hybrid powertrain simulation platform

A forward looking simulation platform for fuel cell hybrid powertrain is developed in Matlab/Simulink environment in this paper. Components of fuel cell hybrid powertrain are tested and characteristic parameters are obtained to build models. The component models are verified by comparing with experiment data. Diver model is constructed for forward looking simulation method. Controller model including power distribution strategy and regenerative braking strategy is separated from component models. The simulation platform is validated with data from testbed experiments. Four configurations of fuel cell hybrid powertrain are studied and analyzed using this simulation platform. Application of the platform shows it is a powerful tool for development of fuel cell vehicle.