Engine Water Pump Cycling for Warm-Up Overheat Control

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Solution Overview

Problem

Existing thermal management systems for vehicle engines do not effectively balance power consumption and prevent local overheating during the warm-up process, particularly at high power and low vehicle speed conditions.

Innovation Solution

A method that controls the water pump to periodically switch between start and stop states, along with adjusting the radiator fan and thermostat, based on engine temperature, power, and speed thresholds, to maintain minimum power consumption and prevent overheating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the water pump operates continuously during engine warm-up, then the engine is prevented from local overheat, but the power consumption of the thermal management system increases

Engineering Contradiction:
Improveprevention of local overheatVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The water pump is controlled to operate periodically rather than continuously during engine warm-up. The control device activates the water pump for a predetermined period after engine start, then stops it, and reactivates it when the engine temperature approaches the upper threshold of the warm-up range. This periodic operation prevents local overheat while reducing overall power consumption compared to continuous operation.

Inventive Principle:
Principle #19Periodic action

2Temperature

If the water pump operates at high speed during warm-up, then heat dissipation is improved, but the power consumption increases

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

Solution Approach 1:

The water pump's operating speed is dynamically adjusted based on engine temperature conditions during warm-up. The control device sets the water pump to a first rotating speed when the engine temperature is below a first threshold, and switches to a second rotating speed when the temperature approaches the upper threshold. This dynamic speed adjustment optimizes heat dissipation while minimizing power consumption.

Inventive Principle:
Principle #15Dynamics

3Stability of the object's composition

If the thermal management system operates continuously, then the engine temperature is maintained, but the power consumption cannot be minimized

Engineering Contradiction:
Improveengine temperature maintenanceVSAvoidpower consumption
Core Design Contradiction:
Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The control device enters a warm-up control mode after a predetermined period following engine start, before the engine reaches normal operating temperature. During this preliminary warm-up phase, the system actively manages temperature by controlling the water pump and radiator fan, then transitions to a power-saving mode when the engine temperature reaches the upper threshold, thereby maintaining temperature stability while minimizing overall power consumption.

Inventive Principle:
Principle #10Preliminary 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

The method effectively prevents engine overheating while minimizing power consumption by optimizing the thermal management system's operation during engine warm-up, especially at high power and low speed conditions.

Implementation Method 1

a water pump (121), an air-cooling radiator (122), a thermostat (123) and a thermal management control device (124)... the engine (110) and the water pump (121) are connected to form a first cooling circulation

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

an air-cooling radiator (122)... controlling a water pump to periodically switch between a start state and a stop state

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP4296482B1Vehicle and thermal management control method and device therefor, and storage medium
Publication Date: 2026.03.11 BYD CO LTD
  • EP4296482B1 patent drawingFigure 1~2
  • EP4296482B1 patent drawingFigure 3

AI summary

A vehicle and a thermal management control method and device therefor, and a storage medium are provided. The vehicle includes an engine and a thermal management system. The thermal management system includes a water pump. The engine and the water pump are connected to form a first cooling circulation. The thermal management control method includes: when a current temperature of the engine is less than or equal to a preset temperature threshold, a total engine power is greater than or equal to a preset power threshold, and a current vehicle speed is less than or equal to a preset vehicle speed threshold, controlling the water pump to periodically switch between a start state and a stop state. In the thermal management control method provided in the the present disclosure, when the engine is in a warm-up mode of high power and low vehicle speed, by controlling the water pump to periodically switch between a start state and a stop state, the local overheat of the engine is avoided and the thermal management system is allowed to be in a minimum power consumption state.