In recent years, concerns about the environment have intensified, and a variety of improvements in fuel efficiency have been made in the automotive industry. Consequently, in order to respond to demands for control of complex systems, control of systems by means of electric motors has become an attractive proposition. However, because many accessories have been motorized, various aspects of vehicles (Battery, weight, etc.) have been subjected to increasing pressures, and it is difficult to reconcile such motorized systems with conflicting demands for compact design and high levels of electrical efficiency.
To achieve a higher degree of electrical power efficiency, which is a key issue, we have developed a new electric oil pump that utilizes a highly efficient design. The design optimizes the motor’s operating point by enhancing the efficiency of both the pump and the motor at the same time. Also, we have developed a new electrical power saving controller that maintains the minimum required output and eliminates ineffective output against ambient temperature change & motor load change. Together with specially developed thermal radiation technology, this has succeeded in reducing the controller’s operating temperature. These highly efficient design techniques allowed for the successful development of a controller integrated Pump & Motor Unit, which can be installed directly on the transmission.
As an example, we will introduce our developed technology for the electric oil pump, which is currently being used in the market in the CVT automatic engine start/shutoff system and the HEV-motor cooling system.