Electric Pump Frequency Control for Quieter Battery Heating

Solution Overview

Problem

The noise generated by the pump when raising the battery temperature in vehicles with liquid-cooling-type thermal management systems, known as pump noise, can detract from the marketability of the vehicle despite the benefits of faster charging and improved performance.

Innovation Solution

A controller adjusts the drive frequency of the electric pump outside the resonance band and suppresses pump noise when background noise is minimal, using pulse width modulation to balance temperature raising and noise suppression.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the pump drives at high frequency to raise battery temperature quickly, then the heating efficiency is improved, but the pump noise increases

Engineering Contradiction:

Improveheating efficiencyVSAvoidpump noise

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The pump drive frequency is dynamically adjusted based on real-time background noise levels. When background noise is large, the pump operates at higher frequency for efficient heating; when background noise is small, the frequency is reduced to minimize pump noise, thus adapting the heating performance to environmental conditions

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The control strategy changes the pump drive frequency parameter according to background noise conditions. By monitoring background noise and adjusting the frequency parameter accordingly, the system achieves optimal balance between heating efficiency and noise suppression

Inventive Principle:

Principle #35Parameter changes

2Object-generated harmful factors

If the pump drive frequency is set outside resonance band to suppress noise, then the pump noise is reduced, but the heating efficiency decreases

Engineering Contradiction:

Improvepump noiseVSAvoidheating efficiency

Core Design Contradiction:

Object-generated harmful factorsVSProductivity

Solution Approach 1:

The pump drive frequency is dynamically adjusted based on real-time background noise levels. When background noise is large, the pump operates at higher frequency for efficient heating; when background noise is small, the frequency is reduced to minimize pump noise, thus adapting the heating performance to environmental conditions

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The control system periodically monitors background noise levels and adjusts pump frequency in response. This periodic measurement and adjustment allows the system to maintain optimal performance while suppressing noise when conditions permit

Inventive Principle:

Principle #19Periodic action

3Reliability

If the pump operates continuously for battery thermal management, then the temperature control is maintained, but the pump noise persists

Engineering Contradiction:

Improvetemperature controlVSAvoidpump noise

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The pump drive frequency is dynamically adjusted based on real-time background noise levels. When background noise is large, the pump operates at higher frequency for efficient heating; when background noise is small, the frequency is reduced to minimize pump noise, thus adapting the heating performance to environmental conditions

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The control strategy changes the pump drive frequency parameter according to background noise conditions. By monitoring background noise and adjusting the frequency parameter accordingly, the system achieves optimal balance between heating efficiency and noise suppression

Inventive Principle:

Principle #35Parameter changes

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 effectively reduces pump noise while maintaining efficient battery temperature management, enhancing vehicle marketability by balancing heating requirements with noise reduction.

Implementation Method 1

a heat medium that exchanges heat with the battery

Methodology Applied

Scientific EffectHeat conduction: Conduction (thermal)

Implementation Method 2

a pump that circulates a heat medium

Methodology Applied

Scientific EffectConvection: Convection

Implementation Method 3

using pulse width modulation to balance temperature raising and noise suppression

Methodology Applied

Scientific EffectPulse width modulation:

Implementation Method 4

sets the drive frequency to be outside the resonance band when the prescribed condition is satisfied

Methodology Applied

Scientific EffectResonance: Resonance

Data Source

PatentUS20250303870A1Vehicle, controller of vehicle, and control method for vehicle

Publication Date: 2025.10.02 TOYOTA JIDOSHA KK

AI summary

A vehicle includes: a battery; a thermal management system; and an ECU. The thermal management system includes an electric pump that circulates a heat medium that exchanges heat with the battery. The thermal management system performs thermal management in the vehicle. When a temperature of the battery is raised using the thermal management system, ECU controls the electric pump such that a noise caused by driving of the electric pump is suppressed when there is no background noise as compared with when there is a background noise, the background noise being a noise caused by a device other than the electric pump.