Power management solutions for hybrid electric vehicles

This paper describes three control strategies for a hybrid electric vehicle, in order to reduce the fuel consumption, and to maintain a reasonable state of charge (SOC) of the battery at the end of the drive cycles. The main goal is to split the requested power from the driver between the internal combustion engine (ICE), and the electric motor (EM), such way to decrease the fuel consumption, and to maintain the dynamic performances. The algorithms were tested using Matlab Simulink and ADVISOR interface. All three strategies are applied to a parallel hybrid power train. The first solution is an original rule-based strategy with the electric motor as a primary power source. The second one is a distributed control strategy for a hybrid electric vehicle. The vehicle is built from control nodes, every one of them having the same priority. The control laws are based on the dc-bus signaling. Every source of power (control node) is entering or leaving the network (dc-bus) depending on the voltage thresholds. The last one is a control strategy for hybrid electric vehicles based on the dynamic programming. Using the fuel converter (FC) fuel map, and SOC of the battery pack, it was designed an algorithm that will choose at each moment the required torque and speed from the first and second source of power.