Method to control a circulation pump, in particular a heating pump
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Solution Overview
Problem
Existing methods for controlling variable speed circulation pumps in heating systems, such as proportional pressure control and Dynamic Control, do not fully optimize energy efficiency by consistently returning to the original control curve, leading to potential undersupply issues and inefficiencies.
Innovation Solution
The method involves detecting a stationary operating point in the hydraulic system, reducing pump speed to achieve minimum system resistance, and adjusting the control curve based on resistance ratios to maintain efficient operation, ensuring the system operates with the lowest possible resistance and optimal energy use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the pump reverts to the originally set control curve, then supply reliability is maintained, but energy efficiency is reduced
Solution Approach 1:
The control curve is transformed from a static, fixed configuration to a dynamic, adaptive one. The control curve is continuously adjusted based on actual system resistance measurements, allowing the pump to optimize its operating point in real-time while maintaining supply reliability. This dynamic adaptation enables energy efficiency improvements without sacrificing reliability.
Solution Approach 2:
The system implements a feedback mechanism where the actual system resistance is continuously measured and used to adjust the control curve. The pump controller monitors the relationship between delivery head and flow rate, compares it with the current control curve, and iteratively optimizes the control curve parameters. This closed-loop feedback enables the system to maintain reliability while improving energy efficiency.
2Use of energy by moving object
If the pump reduces speed to minimize system resistance, then energy consumption decreases, but flow rate stability deteriorates
Solution Approach 1:
The system performs preliminary measurements of system resistance at different operating points before finalizing the control curve optimization. By pre-characterizing the system resistance behavior and using this information to predict optimal operating points, the pump can reduce speed for energy savings while maintaining flow rate stability through informed control decisions.
Solution Approach 2:
The optimization process systematically varies operating parameters (speed, delivery head, flow rate) to identify the optimal operating point that minimizes energy consumption while maintaining acceptable flow rate stability. The control curve parameters are adjusted based on measured system resistance characteristics, enabling the pump to operate at more efficient points without excessive flow fluctuations.
3Use of energy by moving object
If the control curve is frequently adjusted, then energy efficiency improves, but system complexity increases
Solution Approach 1:
The pump controller autonomously performs control curve optimization without requiring external intervention or complex external control systems. The system self-measures its operating parameters, self-calculates system resistance, and self-adjusts the control curve parameters. This self-service capability improves energy efficiency while avoiding the complexity of additional external control hardware or sophisticated user interfaces.
Solution Approach 2:
The system performs control curve optimization at selected intervals rather than continuously, applying partial optimization actions that are sufficient to maintain energy efficiency without requiring constant adjustment. This approach balances energy efficiency improvements with system complexity considerations, implementing just enough optimization to achieve energy savings without over-complicating the control system.
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 continuously optimizes the control curve, reducing energy consumption and preventing undersupply by iteratively adjusting the setpoint to achieve the optimal delivery head, ensuring efficient operation and maintaining system stability.
Implementation Method 1
the pump determines an initial system resistance... reducing the rotational speed... until a minimum system resistance is reached
Data Source
Figure 1
Figure 2a~2c
Figure 3~4
AI summary
The invention relates to a method for controlling a circulation pump having a variable speed in a hydraulic system. The method comprises controlling the speed of the circulation pump according to a stored control curve, recognising whether the hydraulic system is at a stationary operating point, and calculating the initial system resistance. At a stationary operating point, the pump speed is lowered until the minimum system curve is reached, and the minimum system resistance is calculated in order to adapt the control curve for controlling the speed of the circulation pump based on a comparison between the determined initial system resistance and the minimum system resistance.