An optimal separation factor solving method based on a planetary hydraulic drive hybrid vehicle

Abstract

The invention discloses an optimal separation factor solving method based on a planetary hydraulic drive hybrid power vehicle, belongs to the field of new energy vehicles, and is an important controlvariable in a hybrid power vehicle system by taking a separation factor as a proportion index of power output to a mechanical path by an engine to the total output power of the engine. The method provided by the invention starts from the required power of the vehicle; the rotating speed of an engine is calculated according to the vehicle speed, in combination with the influence of the efficiency of two hydraulic pump motors in the system, the working point of the engine enabling the whole hybrid power system to have the optimal efficiency is obtained through reverse iteration, and three timesof iteration correction exist and include separation factor iteration, torque iteration and efficiency iteration. According to solving of the optimal separation factor described by the method, the efficiency of the hydraulic pump is considered, so that the value of the optimal separation factor is more accurate, energy distribution is better optimized and controlled, and the economical efficiencyof the whole vehicle is better.

Description

technical field [0001] The invention belongs to the technical field of hybrid electric vehicles, and in particular relates to a method for calculating an optimal separation factor of a hybrid electric vehicle based on a planetary liquid drive. Background technique [0002] With the increasingly prominent energy crisis, the development of energy saving and new energy vehicles has been paid more and more attention by people. As the main force of new energy vehicles, hybrid electric vehicles are relatively less constrained by battery technology than pure electric vehicles, and are more mature and reliable than fuel cell vehicles. The economic performance is unanimously favored by the market. However, in recent years, both series and parallel configurations of hybrid vehicles have been unable to fully exert their energy-saving effects due to the limitations of their power structures, while hybrid vehicles based on planetary rows combine both series and parallel configurations. ...

AI Technical Summary

Problems solved by technology

[0003] In the patent "A Power Control Method for Parallel Type Hybrid Vehicle" (the authorized announcement number is CN102815295B), an energy management control method for judging the working mode of the vehicle based on the speed of the vehicle and the power demand of the whole vehicle is announced. When working, it is controlled on the optimal working curve, but this method only considers the efficiency of one power component of the engine and does not consider the efficiency difference of other power components under different working conditions, it is difficult to guarantee at every moment The system is working under the condition of optimal economy

[0004] In the patent "A Layered Optimal Control Method for Planetary Hybrid Power System" (publication number CN108545075A), a method of using the instantaneous optimal control strategy to achieve the optimal control of the bottom layer, and adding a global optimization control strategy to achieve the top layer Optimum control achieves better energy saving effect, but does not describe in detail the calculation method of the key parameter separation factor in the instantaneous control strategy

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