Automotive electronic water pump
and a mechanical water pump
The water pump is a crucial component of the automotive engine's cooling system. Its main function is to drive the coolant circulation, absorb excess engine heat, and transfer it to the outside air through the heat dissipation device, thereby preventing the engine temperature from becoming too high.
There are currently two types of automotive water pumps on the market-traditional mechanical water pumps and electronic water pumps.
Mechanical water pump
Most cars currently use mechanical water pumps, which are composed of impellers, water seals, housings, bearings, pulleys and other parts.
Traditional engines generally use mechanical water pumps, which drive the water pump bearings and impellers to rotate through pulleys. The coolant in the water pump is driven by the impeller to rotate together. Under the action of centrifugal force, it is used at the edge of the water pump housing, and a certain pressure is generated at the same time, and then flows out from the outlet or water pipe. The pressure at the center of the impeller is reduced because the coolant is thrown out. The coolant in the radiator is sucked into the water pump through the water pipe under the pressure difference between the water pump inlet and the center of the impeller, realizing the reciprocating circulation of the coolant.
As the name implies, an electronic water pump is an electrically driven water pump. It has a centrifugal impeller at the front end and a motor at the rear end (a brushless DC motor is used).
In addition, there is a circuit board inside it, which is the controller of the water pump, which communicates with the engine control module (ECM).
The ECM adjusts the duty cycle through pulse width modulation (PWM) based on feedback signals such as water temperature and transmits the signal to the controller inside the electronic water pump. The controller controls the motor to rotate according to the duty cycle, thereby driving the impeller to rotate to achieve coolant circulation.
The electronic coolant pump is an electrically driven centrifugal pump.
The motor power is electronically controlled by the electronic module (EWPU)
The electronic module (EWPU) is connected to the engine control unit (DME) via a bit serial data interface.
The engine control unit (DME) determines the required cooling power based on the engine load, operating mode, and temperature sensor data, and sends the relevant information to the electronic module (EWPU) of the electronic coolant pump to control it;
The engine control unit (DME) sets a specific operating mode according to the corresponding driving conditions, so that fuel consumption and power can be affected through the cooling system.
