Optimal Control of a Hybrid Vehicle's Powertrain Minimizing Pollutant Emissions and Fuel Consumption

The paper gives a short description of the University's developments in the field of hybrid electric powertrains and vehicles as well as a survey of theoretical instruments utilized in these works for elaboration of powertrains control strategies. At the present, two units fitted with hybrid powertrains are in operation. These are the four-wheel-drive SUV and the powertrain test rig. Both allow to test different powertrain configurations. Prior to implementing a certain configuration in the rig, a theoretical research of powertrain is conducted to reveal its properties and find a way to control it optimally. The basic tool adopted for that purpose is R.Bellman's dynamic programming (DP). The paper gives an example of applying DP to explore a potential of decreasing fuel consumption and pollutant emissions of a light commercial vehicle by converting its powertrain into hybrid one. During this study, a contradiction has emerged between minimizing fuel consumption and emissions of NO_x. An example shows the way to resolve this contradiction by tuning the cost function. Resulting consumption and emission as well as some control parameters are presented in the remainder of the paper.