Cooling system for power electronic device, and distributed power generation system

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional air cooling methods for power electronic devices are inefficient, leading to poor cooling effects, large equipment sizes, noise, dust accumulation, high energy consumption, and increased environmental temperatures, necessitating additional air conditioning systems.

Innovation Solution

A power electronic device cooling system utilizing a water-cooled air conditioning unit with a coolant pump, bypass throttling elements, and multiple cooling branches, including a cooler that exchanges heat with the device, and a second condenser to enhance cooling efficiency and reliability, allowing the system to operate in a sealed environment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If air cooling is adopted for power electronic device, then cooling can be achieved, but cooling effect is poor and cooling speed is low

Engineering Contradiction:
Improvecooling effectVSAvoidcooling speed
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent transitions from air cooling to liquid cooling by introducing a coolant circulation system with coolant pump, cooler, and condenser. The liquid coolant directly contacts the power electronic device through the cooler, enabling more efficient heat transfer and faster cooling compared to air cooling methods.

Inventive Principle:
Principle #29Pneumatics and hydraulics

Solution Approach 2:

The patent utilizes phase transition of the coolant between liquid and vapor states in the condenser and evaporator to enhance cooling efficiency. The coolant absorbs heat from the power electronic device and releases heat through phase change in the condenser, improving overall cooling performance.

Inventive Principle:
Principle #36Phase transitions

2Reliability

If blower is mounted for air cooling, then cooling function is provided, but equipment size increases

Engineering Contradiction:
Improvecooling functionVSAvoidequipment size
Core Design Contradiction:
ReliabilityVSVolume of moving object

Solution Approach 1:

The patent replaces the blower-based air cooling system with a liquid coolant circulation system. The coolant pump and closed-loop circulation system occupy less space than a blower while providing more effective cooling, thus reducing overall equipment size.

Inventive Principle:
Principle #29Pneumatics and hydraulics

3Temperature

If large air volume blower is used for cooling, then cooling capacity is increased, but noise level increases

Engineering Contradiction:
Improvecooling capacityVSAvoidnoise
Core Design Contradiction:
TemperatureVSObject-generated harmful factors

Solution Approach 1:

The patent replaces the noisy blower with a liquid cooling system using a coolant pump. The liquid coolant circulates through tubes and coolers to transfer heat, eliminating the need for high-velocity air movement and significantly reducing noise generation while maintaining cooling capacity.

Inventive Principle:
Principle #29Pneumatics and hydraulics

4Temperature

If air cooling is used, then cooling is provided, but dust accumulates on components affecting reliability

Engineering Contradiction:
ImprovecoolingVSAvoidcomponent reliability
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent implements a closed-loop liquid cooling system where the coolant circulates through sealed tubes and coolers. This enclosed system prevents dust and contaminants from contacting the power electronic device components, eliminating dust accumulation issues associated with air cooling while providing effective heat removal.

Inventive Principle:
Principle #29Pneumatics and hydraulics

5Speed

If blower exhaust is discharged, then cooling air is moved, but mounting environment temperature increases requiring air conditioning

Engineering Contradiction:
Improveair flowVSAvoidenvironmental temperature
Core Design Contradiction:
SpeedVSTemperature

Solution Approach 1:

The patent uses a closed-loop liquid cooling system with a coolant pump that circulates coolant through the power electronic device and back to the condenser. This system removes heat directly from the device without discharging hot air into the environment, eliminating the need for additional air conditioning in the mounting space.

Inventive Principle:
Principle #29Pneumatics and hydraulics

6Temperature

If conventional air cooling system is used, then cooling is achieved, but energy consumption is high

Engineering Contradiction:
ImprovecoolingVSAvoidenergy consumption
Core Design Contradiction:
TemperatureVSUse of energy by moving object

Solution Approach 1:

The patent implements a liquid cooling system with a coolant pump that operates at lower energy consumption compared to high-power blowers. The liquid coolant efficiently transfers heat from the power electronic device through conduction and convection, requiring less mechanical energy to achieve the same cooling effect.

Inventive Principle:
Principle #29Pneumatics and hydraulics

Solution Approach 2:

The patent utilizes phase change heat transfer in the condenser and evaporator, which provides high heat transfer coefficients and efficient heat removal. This phase transition mechanism enables effective cooling with lower energy input compared to forced air convection systems.

Inventive Principle:
Principle #36Phase transitions

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

The solution provides a high cooling efficiency, reduces equipment size and noise, prevents dust ingress, and ensures continuous operation with improved reliability and extended lifespan by utilizing a coolant circulation system that is independent of air conditioning unit startup and shutdown.

Implementation Method 1

a cooler, and the cooler exchanges heat with a power electronic device to cool the power electronic device

Methodology Applied
Scientific EffectHeat transfer: Heat Exchanger

Implementation Method 2

an evaporative cooling cycle where heat exchange takes place between the heating object 230 and refrigerant flowing out from a radiator 120 and entering into a pressure reducing unit 140

Methodology Applied
Scientific EffectEvaporative cooling: Evaporation

Implementation Method 3

heat exchange takes place between the heating object 230 and refrigerant flowing out from a radiator 120 and entering into a pressure reducing unit 140

Methodology Applied
Scientific EffectCondensation: Condensation

Data Source

PatentEP3051226B1Cooling system for power electronic device, and distributed power generation system
Publication Date: 2019.10.02 GREE ELECTRIC APPLIANCE INC OF ZHUHAI
  • EP3051226B1 patent drawingFigure 1~2
  • EP3051226B1 patent drawingFigure 3

AI summary

The invention discloses a power electronic device cooling system, which includes an air conditioning unit, a coolant pump (31), a bypass throttling element (32) and a cooler. The coolant pump (31) takes liquid from a first condenser (13) of the air conditioning unit, a liquid coolant enters the cooler after being throttled by the bypass throttling element (32), the low-temperature coolant cools a power electronic device at the cooler, and the coolant enters an evaporator (11) of the air conditioning unit to finish a cooling cycle after flowing out of the cooler. The power electronic device cooling system has a good cooling effect, and is high in cooling efficiency, small in equipment size and low in noise, and moreover, the power electronic device may be located in a sealed environment and prevented from influence of dust, and is internally clean and long in operation life.