Online learning method for optimal operating line (OOL) of engine of series-parallel hybrid vehicle

Abstract

The invention discloses an online learning method for an optimal operating line (OOL) of an engine of a series-parallel hybrid vehicle, belongs to the technical field of energy efficiency optimizationof hybrid vehicles, and aims to provide the online learning method which is used for the OOL of the engine of the series-parallel hybrid vehicle, uses the measurable engine rotation speed in a hybridpower system as the correcting value, takes fuel consumption minimization as the target, performs updating and optimization on the engine rotation speed during continuous smooth output of the engineby the aid of the gradient descent algorithm and searches the optimal working point of the engine under the current power demand in real time so as to improve the fuel economy of the whole vehicle. The method includes the steps of an information acquisition module, an engine fuel consumption gradient estimation module, the online learning process for the OOL of the engine fuel consumption gradientand a motor torque control module of the series-parallel hybrid vehicle. By the aid of the method, the online learning efficiency for the optimal operating working curve of the vehicle is improved effectively. The relatively accurate OOL can still be provided for an energy management system by the engine in real time under the influence caused by factors such as environmental migration, aging andthe like, so that the optimal fuel economy of the whole vehicle can be guaranteed.

Description

technical field [0001] The invention belongs to the technical field of hybrid electric vehicle energy efficiency optimization. Background technique [0002] The Optimal Operating Line (OOL) of the engine is a curve formed by connecting the operating points corresponding to the minimum fuel consumption rate under the same output power of the engine. In a hybrid vehicle, the vehicle distributes the power of the engine and the drive motor through energy optimization management according to the driving energy demand of the driver, so that the engine always runs near the economic operating point, thereby achieving the purpose of reducing the fuel consumption of the vehicle. Therefore, accurately obtaining the engine OOL is a prerequisite for implementing an efficient energy management strategy. Considering the influence of factors such as external environment changes and vehicle aging, the precise calibration of engine OOL has become a difficult problem in practical engineering....

AI Technical Summary

Problems solved by technology

Under the influence of external environment (temperature, air pressure) and engine aging and other factors, the actual OOL of the engine will drift to a certain extent near the original curve, and it is difficult to ensure the optimal fuel economy of the vehicle under the same energy management strategy

On the one hand, correcting the drifted OOL by off-line secondary calibration is a huge workload and difficult to realize; The design of the correction method brings great difficulties

Images