Inverter Tension Control Module with Integrated Velocity Loop
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tension control systems in industrial equipment, such as papermaking and textile manufacturing, often experience unbalanced tension due to inconsistent line speeds, leading to higher equipment costs and complexity in adjusting and controlling inverters with tension control functions, as they rely on tension or line speed sensors for feedback.
Innovation Solution
A built-in module for an inverter with integrated tension and velocity closed loops, utilizing arithmetic units and PID controllers to calculate and adjust torque and velocity differences, allowing for tension-balanced operation without the need for sensors, by receiving external tension and velocity commands and performing PID operations to maintain balanced tension and adjust velocity accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If tension or line speed sensors are used for feedback in conventional tension control systems, then measurement precision is improved, but device complexity and equipment costs increase
Solution Approach 1:
The system uses the motor's own encoder feedback and built-in arithmetic units to calculate tension indirectly through mathematical models, eliminating the need for external tension sensors. The motor controller performs self-diagnosis and self-regulation by computing tension from current and velocity data already available in the control system.
Solution Approach 2:
The patent replaces physical tension sensors and mechanical measurement devices with computational methods. Tension is calculated through mathematical models using electrical and motion parameters (current, velocity, acceleration) rather than direct mechanical measurement, substituting electronic computation for mechanical sensing.
2Ease of operation
If line speed control is used as the major control scheme, then ease of operation is improved, but tension balance deteriorates under speed-varying conditions
Solution Approach 1:
The system implements closed-loop feedback control where the calculated tension is continuously compared with the target tension, and the velocity command is adjusted based on the tension error. This feedback mechanism ensures tension balance is maintained even during speed variations, combining the simplicity of velocity control with the stability of tension control.
Solution Approach 2:
The control system dynamically adjusts the velocity command in real-time based on changing tension requirements. The arithmetic units continuously compute the optimal velocity adjustments to maintain tension balance during acceleration, deceleration, and steady-state operation, making the system adaptive to varying operating conditions.
3Manufacturing precision
If multiple inverters and motors are used for winding mechanism control, then manufacturing precision is improved, but device complexity increases
Solution Approach 1:
The patent combines the control functions of multiple inverters and motors into a unified control system with integrated arithmetic units. The tension control module coordinates all driving units through a common feedback loop, merging individual control functions into a coordinated system that maintains tension uniformity while reducing overall complexity.
Solution Approach 2:
The control system performs multiple functions using the same hardware resources. The arithmetic units and feedback mechanisms serve both velocity control and tension control functions, and the encoder feedback is utilized for both speed regulation and tension calculation, making the system multi-functional without requiring separate dedicated components for each function.
Data Source
AI summary
A built-in module for an inverter and having tension control with integrated tension and velocity closed loops, where required tension feedbacks can be obtained by internal calculations of the inverter or feedback signals of a tension sensor. The tension control module is applied to provide a tension control for a winding mechanism which is operated by driving at least one motor. The tension control module firstly builds a tension control to provide a balanced tension to the winding mechanism. Afterward, the tension control module builds a velocity control to provide an accelerated or decelerated adjustment for the winding mechanism. Accordingly, the winding mechanism can stably maintain a tension-balanced operation.