Regulating Valve Calibration Using Pressure-Based Encoder Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing regulating valves in vacuum technology often have encoder values that do not accurately represent the minimum throughflow position, leading to incorrect positioning of the shut-off element and subsequent fluid flow issues.
Innovation Solution
A method is proposed to determine a correction value by measuring pressure values at different positions of the shut-off element using a pressure sensor, identifying the minimum throughflow position as the point of maximum pressure, and calculating the correction value from the corresponding encoder value.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the encoder value is used directly to determine the shut-off element position, then the control system is simple, but the positioning accuracy is poor because the encoder does not output zero at the minimum throughflow position
Solution Approach 1:
The patent applies preliminary action by performing a calibration procedure during system initialization or setup. The method measures pressure values at different encoder positions, identifies the minimum throughflow position (maximum pressure), and calculates a correction value before normal operation begins. This pre-calibration eliminates positioning errors without adding complexity to the ongoing control system.
Solution Approach 2:
The patent changes the parameter representation by introducing a correction value that offsets the encoder's non-zero starting position. Instead of modifying the encoder hardware, the system transforms the encoder output by applying a calculated correction factor, allowing accurate position determination despite the encoder not outputting zero at the minimum throughflow position.
2Reliability
If the shut-off element position is not accurately determined, then the regulating valve can be operated simply, but the fluid flow control becomes inaccurate
Solution Approach 1:
The patent introduces pressure measurement as an intermediary indicator to detect the minimum throughflow position. Instead of directly measuring the shut-off element position, the system uses pressure values as a mediator - the position at which maximum pressure occurs corresponds to the minimum throughflow position, enabling accurate detection without complex position sensing.
Solution Approach 2:
The patent implements feedback by continuously monitoring pressure values at different encoder positions and using this information to determine the correct minimum throughflow position. The system feeds back the relationship between encoder values and pressure measurements to establish a correction value, ensuring accurate fluid flow control based on actual system behavior rather than assumed positions.
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 method allows for accurate determination of the minimum throughflow position and correction value, ensuring precise control of fluid flow through the regulating valve, thereby addressing the inaccuracies in existing systems.
Implementation Method 1
a pressure value, in particular which is representative of the fluid in the chamber, is measured with a pressure sensor in mutually different positions of the shut-off element
Data Source
AI summary
A method for determining a correction value for a regulating device for a regulating valve. The regulating valve regulates a fluid flow through a chamber, and a shut-off element of the regulating valve is placed by the regulating device by an actuator of the regulating valve in mutually different positions relative to a throughflow opening for the fluid flow. An encoder is provided and each position of the shut-off element corresponds to an encoder value. A pressure value, in particular which is representative of the fluid in the chamber, is measured with a pressure sensor in mutually different positions of the shut-off element. The position of the shut-off element at which a maximum of the pressure values is measured is identified by the regulating device as the minimum throughflow position of the shut-off element. The correction is determined from the encoder value at which the minimum throughflow position is identified.