Dual-Function Coolant Tank for Hybrid Power Systems

Solution Overview

Problem

Vehicular hybrid power systems face challenges in optimizing manufacturing costs, maintenance costs, and space requirements due to the need for effective cooling of components like the generator engine and inverter assembly, which are not adequately addressed by existing cooling systems.

Innovation Solution

A dual-function coolant tank system that acts as both a generator engine coolant overflow reservoir and an expansion and pressure head tank for the inverter assembly cooling circuit, combined with a liquid coolant pumping system and heat exchanger, utilizing engine-driven cooling air to efficiently transfer cooling liquid between the generator and inverter assemblies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate coolant systems are used for generator engine and inverter assembly, then each component can be cooled independently, but space requirements and manufacturing costs increase

Engineering Contradiction:

Improvecooling effectivenessVSAvoidspace requirements

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent combines the generator engine coolant overflow reservoir and inverter assembly expansion/pressure head tank into a single dual-function coolant tank. This merging of previously separate cooling system components reduces the overall space required while maintaining independent cooling capability for both the generator engine and inverter assembly through shared coolant circulation.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The coolant tank is designed to perform multiple functions simultaneously: it serves as the overflow reservoir for the generator engine cooling system and as the expansion and pressure head tank for the inverter assembly cooling circuit. This multi-functionality eliminates the need for separate dedicated tanks for each cooling system, thereby reducing space requirements and manufacturing costs.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If separate coolant systems are used for generator engine and inverter assembly, then each component can be cooled independently, but manufacturing costs increase

Engineering Contradiction:

Improvecooling effectivenessVSAvoidmanufacturing costs

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines the generator engine coolant overflow reservoir and inverter assembly expansion/pressure head tank into a single dual-function coolant tank. This merging of previously separate cooling system components reduces the overall space required while maintaining independent cooling capability for both the generator engine and inverter assembly through shared coolant circulation.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The coolant tank is designed to perform multiple functions simultaneously: it serves as the overflow reservoir for the generator engine cooling system and as the expansion and pressure head tank for the inverter assembly cooling circuit. This multi-functionality eliminates the need for separate dedicated tanks for each cooling system, thereby reducing space requirements and manufacturing costs.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Temperature

If the liquid coolant pumping system is always on, then the inverter assembly is continuously cooled, but parasitic load on user electrical power increases

Engineering Contradiction:

Improveinverter assembly coolingVSAvoidparasitic load

Core Design Contradiction:

TemperatureVSUse of energy by moving object

Solution Approach 1:

The liquid coolant pumping system is designed with dynamic control capability, allowing it to be turned on and off based on the cooling requirements of the inverter assembly. The system activates the pump only when predetermined temperature thresholds are reached, rather than operating continuously, thereby reducing parasitic electrical load while maintaining effective cooling when needed.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The coolant pumping system operates periodically rather than continuously, activating only when temperature sensors detect that the inverter assembly has reached predetermined temperature threshold values. This periodic operation reduces energy consumption and parasitic load on the electrical power system while ensuring cooling is provided when thermally required.

Inventive Principle:

Principle #19Periodic action

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 solution reduces space and manufacturing costs, provides efficient cooling, and simplifies maintenance by using a single coolant tank for both systems, ensuring reliable operation and reducing parasitic loads on user electrical power.

Implementation Method 1

access to cooling air provided by the engine driven electrical power generator with a heat exchanger

Methodology Applied

Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

acts as an expansion and pressure head tank for an inverter assembly cooling circuit

Methodology Applied

Scientific EffectPressure head: Pressure Gradient

Data Source

PatentUS7343884B1Coolant system for hybrid power system

Publication Date: 2008.03.18 CUMMINS POWER GENERATION INC

AI summary

A cooling system for a hybrid power system that includes an engine such as a generator engine, and a power converter such as an inverter, includes an engine cooling circuit, a power converter cooling circuit and a common coolant tank operatively coupled to both the engine and the power converter via the engine cooling circuit and the power converter cooling circuit respectively.