hardware in the loop simulation

This paper presents a method for maintaining the battery safe operating voltage region in a hybrid electric vehicle. Using the instantaneous value for the battery voltage in the proposed method, the traction motor maximum torque is limited through an interaction between the BMS and vehicle control unit. Unlike the methods based on battery State of Power (SoP) estimation in which the battery safe operation cannot be guaranteed because of the model-based nature, performance of the proposed method does not rely on the precision of battery modelling and can be used in different life conditions for the battery. In addition, due to low computational costs, the proposed algorithm can be easily implemented on the BMS. Performance of the designed algorithm has been evaluated in a Hardware-in-the-Loop (HiL) test bench for a series hybrid electric bus and compared with the results of SoP estimation based methods. Results indicate the improvement towards maintaining the safe operating voltage region in various life conditions for the battery.

Appropriate control of the vehicle longitudinal dynamic requires accurate and real-time knowledge of the parameters affecting the dynamics of the vehicle. The main contribution of this paper is in developing an estimator called short-time linear quadratic form (STLQF) which is a new parameter estimation technique to simultaneously estimate the time-varying parameters that affect on vehicle longitudinal dynamics with a low latency. These parameters are the vehicle mass, time varying road slope angle and overall aerodynamic drag coefficient of the vehicle in real time. Next, the efficiency of STLQF algorithm is shown by comparing the results of STLQF technique in an experimental test against the recursive least squares (RLS) parameter estimation method. The results of implementing STLQF parameter estimation algorithm, showes the better performance of STLQF estimator compared with RLS algorithm. In the end, the STLQF estimator is simulated in hardware in the loop configuration using an AVR microcontroller in order to rapid prototype of the STLQF method by minimum cost and high accuracy in the least possible time.