Charging Station Relay Sticking Detection Via Auxiliary Circuit

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Solution Overview

Problem

Conventional relay sticking detection in neutral wire circuits of charging stations suffers from low accuracy due to reliance on small voltages between neutral and ground wires, making it difficult to determine relay status accurately.

Innovation Solution

A system and method that includes a live wire circuit, neutral wire circuit, ground wire circuit, and a detection voltage acquisition module, with a preset auxiliary detection circuit using a resistor greater than a threshold, to form a short circuit connection between the neutral and live wire circuits, allowing for high-accuracy relay sticking detection based on charging state and calculated sticking values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional detection method using small voltage between neutral and ground wires is used, then the detection circuit is simple, but the detection accuracy is low

Engineering Contradiction:
Improverelay sticking detection accuracyVSAvoiddetection circuit complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces an auxiliary detection circuit as an intermediary component between the neutral wire circuit and live wire circuit. This auxiliary circuit includes an auxiliary resistor and auxiliary switch that mediate the detection process, enabling accurate measurement of relay sticking status by creating a controllable detection path that doesn't directly interfere with normal circuit operation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the detection parameter from small voltage between neutral and ground wires to voltage between neutral wire and live wire through the auxiliary detection circuit. By utilizing the larger voltage difference and controlled resistance values in the auxiliary circuit, the detection accuracy is significantly improved while maintaining circuit safety.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If auxiliary detection circuit with high resistance is introduced, then detection accuracy is improved, but circuit complexity increases

Engineering Contradiction:
Improvesticking detection value accuracyVSAvoidauxiliary detection circuit components
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The auxiliary detection circuit is designed to serve multiple functions: it enables sticking detection, provides circuit isolation, and allows for safe measurement. The auxiliary resistor and switch are integrated into the existing charging pile control circuitry, allowing the same components to serve both normal operation and detection purposes, thereby reducing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The auxiliary switch is configured to be closed only during the detection phase, establishing the detection circuit path in advance before measurement occurs. This preliminary configuration ensures that the high-resistance auxiliary circuit is only activated when needed, minimizing its impact on normal circuit operation and reducing perceived complexity.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If voltage acquisition is performed during charging state, then detection is performed under actual working conditions, but voltage fluctuations may affect measurement stability

Engineering Contradiction:
Improvedetection under actual charging conditionsVSAvoidvoltage measurement stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The detection system incorporates feedback mechanisms where the control circuit monitors the charging state and dynamically adjusts the detection process. The auxiliary switch is controlled based on feedback about the charging status, ensuring detection occurs at appropriate moments when voltage conditions are favorable, thereby maintaining both reliability and stability.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The detection system is designed to be dynamic, adapting to different charging states. The auxiliary detection circuit is activated and deactivated based on real-time charging conditions, and detection parameters are adjusted dynamically to maintain measurement stability despite voltage fluctuations during different charging phases.

Inventive Principle:
Principle #15Dynamics

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

Improves the accuracy of relay sticking detection in neutral wire circuits by ensuring high resistance and voltage levels, enabling precise determination of relay states under varying charging conditions.

Implementation Method 1

The preset auxiliary detection circuit includes a preset auxiliary resistor, and a resistance of the preset auxiliary resistor is greater than or equal to a preset threshold

Methodology Applied
Scientific EffectElectrical Resistance: Electrical Resistance

Data Source

PatentEP4641226A1System and method for detecting sticking of relay, electronic apparatus, and medium
Publication Date: 2025.10.29 SUNGROW CHARGING TECH CO LTD
  • EP4641226A1 patent drawingFigure 1
  • EP4641226A1 patent drawingFigure 2
  • EP4641226A1 patent drawingFigure 3

AI summary

A system and a method for detecting sticking of a relay, an electronic apparatus, and a medium are provided. In the system, a preset auxiliary detection circuit is provided between a neutral wire circuit and a live wire circuit of a charging station, and a resistance of a preset auxiliary resistor is greater than or equal to a preset threshold, so that a short circuit connection can be formed between the neutral wire circuit and the live wire circuit. In combination with the preset auxiliary resistor in the detection circuit, the accuracy of a current between the neutral wire circuit and the live wire circuit in the charging station is improved. In a case that relay sticking detection is performed based on a voltage between the neutral wire circuit and a ground wire circuit, the relay sticking detection of the neutral wire circuit can be performed based on a calculated sticking detection value with high accuracy. Since the charging station is in different circuit conduction conditions under different charging states, the relay sticking detection of the neutral wire circuit is performed based on an actual charging state of the charging station and the sticking detection value. The accuracy of the relay sticking detection of the neutral wire circuit is improved.