Electric Drive Oil Pump Speed Control for Churning Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric drive assemblies in new energy vehicles suffer from inefficiencies due to high assembly losses, particularly oil churning losses and oil pump power consumption, as current lubrication and cooling methods do not effectively adjust lubricating oil levels to optimize efficiency across varying conditions.
Innovation Solution
A control method that adjusts the rotational speed of the oil pump based on the motor's rotational speed, oil pump speed, and lubricating oil temperature to actively manage lubricating oil levels, minimizing losses and optimizing efficiency by controlling the liquid level and power consumption of the oil pump.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the electronic oil pump is used to cool and lubricate the motor and reducer, then the cooling and lubrication function is ensured, but the assembly loss increases and assembly efficiency decreases
Solution Approach 1:
The patent applies dynamics by making the oil pump rotational speed adjustable rather than fixed. The control device dynamically adjusts the oil pump speed based on real-time monitoring of motor speed, oil temperature, and other parameters, allowing the system to adapt to varying operating conditions and minimize energy loss while ensuring adequate cooling and lubrication.
Solution Approach 2:
The patent changes the parameter of oil pump rotational speed from a fixed value to a variable parameter that can be adjusted according to operating conditions. By modifying this key parameter based on motor speed and temperature feedback, the system optimizes the balance between cooling/lubrication effectiveness and energy consumption.
2Reliability
If the oil pump rotational speed is increased to improve cooling and lubrication, then the lubrication effect improves, but the oil pump power consumption increases
Solution Approach 1:
The patent implements feedback control by continuously monitoring oil temperature, motor speed, and oil pump speed, then using this information to adjust the oil pump rotational speed. The control device receives feedback from sensors and dynamically adjusts the pump speed to maintain optimal lubrication while minimizing power consumption, avoiding both over-pumping and under-pumping conditions.
Solution Approach 2:
The system transitions from a static oil pump speed to a dynamic adjustable speed that responds to real-time operating conditions. This allows the oil pump to operate at optimal speeds varying with load and temperature, reducing unnecessary energy consumption while maintaining adequate lubrication effect.
3Use of energy by moving object
If the oil pump rotational speed is decreased to reduce power consumption, then the power consumption decreases, but the cooling and lubrication effect deteriorates
Solution Approach 1:
The feedback mechanism ensures that oil pump speed is not reduced below the level required for adequate cooling and lubrication. Temperature sensors monitor the thermal state of the motor and reducer, and the control device adjusts the pump speed upward when temperature rises, preventing deterioration of the cooling and lubrication effect while minimizing power consumption during normal operation.
Solution Approach 2:
The system performs self-adjustment based on its own operational state. The control device automatically monitors temperature, motor speed, and pump speed, and adjusts the pump speed without external intervention to maintain optimal cooling and lubrication, ensuring the system serves its own lubrication needs efficiently.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances assembly efficiency by reducing oil churning losses and power consumption, thereby improving the endurance mileage of the vehicle.
Implementation Method 1
The electronic oil pump is used to pump lubricating oil to each friction part of the motor, so that the lubricating oil is circulated in a lubrication loop
Implementation Method 2
an electronic oil pump is usually used to cool and actively lubricate a motor and a reducer
Implementation Method 3
The electronic oil pump is used to pump lubricating oil to each friction part of the motor, so that the lubricating oil is circulated in a lubrication loop to ensure good cooling and lubrication of the motor
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Embodiments of this application relate to the control field, and provide a control method and apparatus. The control method and apparatus may be applied to an electric drive system. The electric drive system includes an oil pump, a motor, a reducer, and a housing, the motor and the reducer are disposed in the housing, lubricating oil is stored in the housing, and the oil pump is configured to pump the lubricating oil. The method includes: obtaining a first rotational speed of the motor, a second rotational speed of the oil pump, and a temperature of the lubricating oil in the housing; and controlling a rotational speed of the oil pump to be a third rotational speed based on the first rotational speed, the second rotational speed, and the temperature. In this way, the rotational speed of the oil pump can be adjusted to change liquid levels of the lubricating oil in a cavity and oil pump power at different rotational speeds of the oil pump, so that assembly efficiency is effectively improved.