Design and application of electric oil pump in automatic transmission for efficiency improvement and start–stop function

For the purpose of improving efficiency and realizing start–stop function, an electric oil pump(EOP) is integrated into an 8-speed automatic transmission(AT). A mathematical model is built to calculate the transmission power loss and the hydraulic system leakage. Based on this model, a flow-based control strategy is developed for EOP to satisfy the system flow requirement. This control strategy is verified through the forward driving simulation. The results indicate that there is a best combination for the size of mechanical oil pump(MOP) and EOP in terms of minimum energy consumption. In order to get a quick and smooth starting process, control strategies of the EOP and the on-coming clutch are proposed. The test environment on a prototype vehicle is built to verify the feasibility of the integrated EOP and its control strategies. The results show that the selected EOP can satisfy the flow requirement and a quick and smooth starting performance is achieved in the start–stop function. This research has a high value for the forward design of EOP in automatic transmissions with respect to efficiency improvement and start–stop function.

Review of research on intelligent diagnosis of oil transfer pump malfunction

Oil transfer pump is the key dynamic equipment in the process of oil and gas gathering and transportation,and its working reliability directly affects the safety of oil and gas storage and transportation.Intelligent diagnosis is a key technical method to reduce failure rate of oil transfer pump,ensure the safety of gathering and transportation process,and avoid major safety accidents caused by oil transfer pump failure.Various oil transfer pumps have been emerged in recent decades,and the common fault types and characteristics of oil transfer pump have been brought out in the review.This article highlights on the research of the fault signal and processing methods of oil transfer pump.Firstly,the fault signal of the oil transfer pump is discussed and the advantages and disadvantages of different signal extraction are analyzed.Secondly,the intelligent diagnosis method of oil transfer pump and the shortcomings of the existing methods are pointed out.Finally,the conclusions are given and the future development perspectives of oil transfer pumps are suggested.The main contribution of this review is to give a syn-thetic understanding on oil transfer pumps.