Selection of battery parameters for a M₁ category hybrid vehicle

BACKGROUND: To optimize the operation of a hybrid vehicle power plant, it is necessary to select the parameters of its traction battery correctly, which significantly affect the control algorithm and charge-discharge balance. The presence of a method that helps to make a reasonable choice depending on the characteristics of the target vehicle, the conditions and modes of its operation will make it possible to increase energy efficiency indicators. AIM: Development of the method for calculating the parameters of a hybrid vehicle traction battery using the energy charge-discharge balance of its power plant. METHODS: A mathematical model of the charge-discharge energy balance has been proposed. Using this model, it is possible to make appropriate calculations on the amount of energy expended by the power plant when a vehicle moving through the stages of the European urban cycle, and to analyze various algorithms for controlling the power plant to achieve maximal energy efficiency, as well as to select capacity and power of a traction battery. The basis for the calculations was the cycle described in the UN Regulation No. 83. RESULTS: The process of energy accumulation in a traction battery is considered, and criteria for choosing an algorithm for the operation of the vehicle’s power plant are indicated. The energy of vehicle motion in the urban cycle was determined, taking into account the operating time of the units, and the charge-discharge energy balance was calculated, which, in turn, made it possible to find the proper battery capacity. It has been found that the battery charge value at the end of the cycle should be equal to the initial value, which allows the use of a lower capacity battery and ensures maximal energy efficiency of the power plant. Also, based on the calculation results, recommendations were made regarding the optimization of the specific energy and weight-size parameters of the battery. CONCLUSION: The proposed method is helpful to make a reasonable choice of а hybrid vehicle power plant parameters to ensure its energy efficiency.