High Voltage Current Protection Circuit with Inversion Detection

Solution Overview

Problem

Conventional over-current protection systems for high-voltage systems fail to protect the system when load failures occur, as the current does not flow through the detection component on the low voltage side, leading to potential component damage and unsafe system failures.

Innovation Solution

A current protection circuit that monitors and amplifies the current flowing through the high voltage bus, using NPN or PNP type bipolar junction transistors to control the power supply and load, disconnecting or limiting current when thresholds are exceeded, thereby preventing damage and ensuring system stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If current protection is implemented on the low voltage side, then the detection component can monitor current, but the protection fails when load failure occurs and current does not flow through the detection component

Engineering Contradiction:

Improveprotection reliabilityVSAvoidprotection coverage

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent inverts the conventional protection approach by moving the current detection from the low voltage side to the high voltage side. The detection component is now connected in series with the high voltage bus, allowing it to monitor current flow directly at the power supply output. This inversion ensures that all current, including fault current, must pass through the detection component, eliminating the protection blind spots of the conventional low-voltage-side approach.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent introduces a high voltage switch tube as an intermediary component between the power supply and the load. This switch tube is controlled by the control module based on detection signals from the detection component. When overcurrent is detected, the control module adjusts the duty cycle of the high voltage switch tube to limit or cut off current flow, providing active protection mediation that responds dynamically to fault conditions.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If current protection is implemented on the low voltage side, then the system structure is simpler, but the protection scope is limited and cannot detect all fault conditions

Engineering Contradiction:

Improvesystem structure complexityVSAvoidprotection effectiveness

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent inverts the conventional protection approach by moving the current detection from the low voltage side to the high voltage side. The detection component is now connected in series with the high voltage bus, allowing it to monitor current flow directly at the power supply output. This inversion ensures that all current, including fault current, must pass through the detection component, eliminating the protection blind spots of the conventional low-voltage-side approach.

Inventive Principle:

Principle #13The other way round (Inversion)

3Ease of manufacture

If conventional low voltage side protection is used, then cost is reduced, but system stability and safety are compromised

Engineering Contradiction:

Improvecost effectivenessVSAvoidcomponent damage risk

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent implements preliminary protection action by detecting current abnormalities at the high voltage side before they can cause damage to components. The detection component continuously monitors the current flowing through the high voltage bus, and when overcurrent conditions are detected, the control module immediately adjusts the high voltage switch tube duty cycle to limit current flow, preventing component damage before it occurs.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces a high voltage switch tube as an intermediary component between the power supply and the load. This switch tube is controlled by the control module based on detection signals from the detection component. When overcurrent is detected, the control module adjusts the duty cycle of the high voltage switch tube to limit or cut off current flow, providing active protection mediation that responds dynamically to fault conditions.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 provides wider protection scope and improved reliability for high-voltage systems, preventing component damage and ensuring system stability by monitoring and controlling current on the high voltage side, thus enhancing cost-effectiveness and reliability compared to conventional low-voltage side protection methods.

Implementation Method 1

the value of the amplified current signal is greater than a preset threshold value, the control module receives a determined digital level signal

Methodology Applied

Scientific EffectBipolar junction transistor amplification:

Data Source

PatentUS11418023B2Current protection circuit and method for high voltage system

Publication Date: 2022.08.16 FUTRONICS NA CORP

AI summary

A current protection circuit for a high voltage system includes: a power supply module to supply power to a load through a high voltage bus and a low voltage bus; a detection module connected to the high voltage bus and used to detect a value of current flowing through the high voltage bus; a signal processing module electrically connected to the detection module and used to amplify the current flowing through the high voltage bus; and a control module electrically connected to the signal processing module, the power supply module, and the load, and used to disconnect the load from the power supply module or perform current limiting for the load when the value of the amplified current exceeds a preset threshold.