Electric Pump PWM Sleep Control for Low Quiescent Current

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Solution Overview

Problem

The microcontroller in electric pump control systems continues to consume power even when the electric pump is stationary, leading to increased quiescent current and power consumption due to failure to enter sleep mode effectively.

Innovation Solution

A mode control method and system that utilizes pulse-width modulation (PWM) signals to determine the target rotational speed of the electric pump, entering sleep mode when the speed remains zero for a set duration and working mode otherwise, thereby reducing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the microcontroller continues to run in working mode when the electric pump is stationary, then the control system can respond quickly to any changes, but the quiescent current and power consumption of the microcontroller increase significantly

Engineering Contradiction:
Improveresponse readinessVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The microcontroller dynamically switches between working mode and sleep mode based on the operational state of the electric pump. When the pump is running, the microcontroller operates in working mode for full functionality. When the pump is stationary for a predetermined time, the microcontroller transitions to sleep mode to reduce power consumption, and can wake up when needed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The microcontroller changes its operational parameters by switching between different operating modes (working mode and sleep mode). This parameter change allows the system to optimize between power consumption and responsiveness based on real-time conditions, specifically when the electric pump remains stationary for a predetermined duration.

Inventive Principle:
Principle #35Parameter changes

2Use of energy by moving object

If the microcontroller enters sleep mode to reduce power consumption, then the quiescent current decreases, but the system may experience delayed response to control commands

Engineering Contradiction:
Improvepower consumptionVSAvoidresponse time
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The microcontroller enters sleep mode only after detecting that the electric pump has been stationary for a predetermined time period. This preliminary condition ensures that the microcontroller does not enter sleep mode during transient stop periods, maintaining system responsiveness when actually needed while still achieving power savings during extended idle periods.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If the microcontroller continuously monitors the electric pump status, then the system can accurately determine when to enter sleep mode, but additional power is consumed during monitoring

Engineering Contradiction:
Improvespeed detection accuracyVSAvoidmonitoring power
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The microcontroller continuously monitors the electric pump status by reading the PWM signal duty cycle, which is essential for accurate determination of when to enter sleep mode. This continuous monitoring ensures precise speed detection (including zero speed) while the microcontroller remains in working mode, enabling accurate control decisions.

Inventive Principle:
Principle #20Continuity of useful action

Data Source

PatentEP3806321B1Mode control method and system, and electronic apparatus and storage medium
Publication Date: 2023.12.27 ZHEJIANG SANHUA INTELLIGENT CONTROLS CO LTD
  • EP3806321B1 patent drawingFigure 1
  • EP3806321B1 patent drawingFigure 2~3
  • EP3806321B1 patent drawingFigure 4

AI summary

Provided is a mode control method that includes obtaining a PWM signal; obtaining a duty cycle of the PWM signal; obtaining a target rotational speed of an electric pump based on the duty cycle of the PWM signal; in response to determining that the target rotational speed of the electric pump is equal to 0 and the target rotational speed of the electric pump remains equal to 0 for the set duration, entering the sleep mode by the microcontroller; and in response to determining that the target rotational speed of the electric pump is not equal to 0 or the target rotational speed of the electric pump does not remain equal to 0 for the set duration, entering the working mode by the microcontroller. Further provided are a mode control system, an electronic device and a storage medium.