Hydronic Air Conditioning Control for Minimum Pump and Heat Source Power

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing air conditioning systems face high costs and complex calculations to minimize total power consumption by the heat source unit and pump, requiring extensive test operation data to determine optimal supply water temperatures for efficient operation.

Innovation Solution

An air conditioning system with a heat source unit, indoor unit, water circuit, flow rate adjusting valve, and adjustable pump, along with sensors and controllers to adjust the supply water temperature based on the temperature difference between return and supply water, allowing for a simple calculation to determine the target supply water temperature.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by stationary object

If the supply water temperature is lowered to reduce pump power consumption, then the pump power consumption decreases, but the heat source unit power consumption increases due to decreased COP

Engineering Contradiction:
Improvepump power consumptionVSAvoidheat source unit power consumption
Core Design Contradiction:
Use of energy by stationary objectVSUse of energy by moving object

Solution Approach 1:

The system dynamically adjusts the supply water temperature as a variable parameter to optimize the balance between heat source unit COP and pump power consumption. By changing the temperature parameter based on operating conditions, the system achieves minimum total power consumption without requiring complex correlations.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The system uses feedback from temperature sensors and power consumption measurements to continuously adjust the supply water temperature. This closed-loop control enables the system to adapt to changing conditions and maintain optimal efficiency without pre-determined correlation data.

Inventive Principle:
Principle #23Feedback

2Loss of energy

If extensive test operation data is collected and complex calculations are performed to determine optimal supply water temperature, then the power consumption optimization is achieved, but the system cost increases

Engineering Contradiction:
Improvetotal power consumptionVSAvoidsystem cost
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The invention extracts only the essential parameter (supply water temperature) needed for optimization, eliminating the need for extensive test data collection and complex correlation calculations. This simplification reduces system cost while maintaining optimization capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The system uses simple, easily obtainable operational parameters (temperature readings and power consumption data) instead of expensive, complex correlation models. This approach achieves optimization using low-cost measurements rather than high-cost pre-determined relationships.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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 system minimizes total power consumption by the heat source unit and pump through a straightforward calculation process, reducing system costs and optimizing energy efficiency.

Implementation Method 1

a heat source unit capable of adjusting a cooling capacity or a heating capacity for generating cold or hot water

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

an indoor unit configured to exchange heat between sucked air and the cold or hot water and blow out the air

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 3

a pump provided in the water circuit, of which rotation speed is adjustable

Methodology Applied
Scientific EffectPumping: Pump

Data Source

PatentEP3882524B1Air conditioning system
Publication Date: 2023.11.08 MITSUBISHI ELECTRIC CORP
  • EP3882524B1 patent drawingFigure 1~2
  • EP3882524B1 patent drawingFigure 3~4
  • EP3882524B1 patent drawingFigure 5~6

AI summary

An air conditioning system includes: a heat source unit; an indoor unit; a water circuit configured by connecting a supply pipe and a return pipe so that the cold or hot water circulates to the heat source unit and the indoor unit; a flow rate adjusting valve provided in the water circuit and capable of adjusting a flow rate of the cold or hot water; a supply air temperature control unit configured to adjust a flow rate of the flow rate adjusting valve; a pump provided in the water circuit and capable of adjusting a rotation speed; a pump controller configured to control the rotation speed of the pump; a return water temperature sensor configured to detect a temperature of the cold or hot water flowing through the return pipe; a supply water temperature sensor configured to detect a temperature of the cold or hot water flowing through the supply pipe; a supply water temperature control unit configured to adjust the cooling capacity or the heating capacity of the heat source unit so that the supply water temperature detected by the supply water temperature sensor becomes a target supply water temperature; and a target supply water temperature updating unit configured to change the target supply water temperature based on a temperature difference between the return water temperature detected by the return water temperature sensor and the supply water temperature.