Oil Pressure Control Device with Load Variation Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor control systems for hydraulic pumps in machine tools face delays in response to sharp changes in load, resulting in longer-than-expected response times and high power consumption due to constant high-speed motor operation.
Innovation Solution
An oil pressure control device that includes an oil pressure sensor, a speed instruction unit, a torque instruction unit, and a current control unit, with a load variation compensation unit that adds a compensation speed to the speed instruction value based on the oil pressure determination value or a load operation pattern, to quickly adjust motor speed and flow rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If the motor is rotated at a constant high speed to maintain oil pressure, then the oil pressure can be maintained at a desirable level, but high power consumption and loud noise result
Solution Approach 1:
The motor speed is changed from constant to variable, dynamically adjusting speed based on actual load requirements and oil pressure conditions, allowing the motor to operate at lower speeds when full power is not needed, thus reducing power consumption while maintaining required oil pressure levels
Solution Approach 2:
A feedback control system using oil pressure sensors and motor position sensors continuously monitors system conditions and adjusts motor speed accordingly, enabling the motor to maintain oil pressure at desirable levels only when necessary, thereby reducing unnecessary power consumption and noise
2Stress or pressure
If the motor is rotated at a constant high speed to maintain oil pressure, then the oil pressure can be maintained at a desirable level, but a loud noise is emitted
Solution Approach 1:
The motor operates at variable speeds rather than constant high speed, dynamically adjusting rotational speed to match actual hydraulic system demands, which significantly reduces noise emission during low-demand operations while still maintaining required oil pressure when needed
3Use of energy by moving object
If proportional-integral control is used to control motor speed based on hydraulic deviation, then power consumption is reduced, but response time to sharp load changes increases
Solution Approach 1:
The system performs preliminary actions by predicting load changes based on motor position differentiation and preparing compensation in advance, allowing the control system to respond more quickly to sharp load changes without requiring high constant motor speed, thus reducing both response time and power consumption
Solution Approach 2:
A enhanced feedback control system incorporates motor position differentiation and load variation compensation to detect and respond to load changes more quickly than conventional proportional-integral control, reducing response time while maintaining the power consumption benefits of variable speed operation
Data Source
AI summary
An oil pressure control device for supplying oil pressure by rotating a hydraulic pump, by means of a motor, comprises an oil pressure sensor; a speed instruction operation unit for outputting a speed instruction value, based on a difference between an oil pressure determination value from the oil pressure sensor and an oil pressure instruction value; a torque instruction value operation unit for calculating a torque instruction value, based on a difference between a speed determination value and the speed instruction value; and a current control unit for controlling a current of the motor, based on the torque instruction value, and adds the load variation compensation speed outputted from the load variation compensation unit and the speed instruction value.