Power Supply Assembly Bypass Switch Short Circuit Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Detecting a short circuit in the bypass switch system of a power supply assembly during the converter supply mode is difficult due to the potential for exceeding maximum allowed voltage in the load supply converter system.

Innovation Solution

Generating a diagnostic voltage within the load supply converter system that differs from the primary alternating current supply voltage, causing a short-circuit current to flow through the bypass switch system, thereby indicating a short circuit, which can be detected by reprogramming the control system of the power supply assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If power is transferred through the load supply converter system during converter supply mode, then energy saving is achieved by bypassing the converter, but detecting a short circuit in the bypass switch system becomes difficult

Engineering Contradiction:
Improveenergy savingVSAvoidshort circuit detection difficulty
Core Design Contradiction:
Loss of energyVSDifficulty of detecting and measuring

Solution Approach 1:

The control system proactively generates a diagnostic voltage signal at a predetermined frequency before normal operation to test the bypass switch system. This preliminary diagnostic action allows detection of short circuits in the bypass switches while maintaining the energy-saving bypass configuration, resolving the contradiction between energy saving and detection capability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

A diagnostic voltage signal at a predetermined frequency serves as an intermediary test signal. This signal is injected into the power connection and allows the control system to detect short circuits in the bypass switch system without disrupting normal power transfer through the converter, enabling detection while maintaining energy efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If a diagnostic voltage is generated to detect short circuit, then short circuit detection capability is improved, but voltage stability in the power connection is affected

Engineering Contradiction:
Improveshort circuit detection capabilityVSAvoidvoltage stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The diagnostic voltage is generated as a periodic signal at a predetermined frequency that is distinct from the normal power frequency. This periodic diagnostic signal allows the control system to detect short circuits by analyzing current response at the diagnostic frequency, while the normal power transmission continues unaffected at its own frequency, maintaining voltage stability.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The diagnostic voltage signal uses a predetermined frequency parameter that is different from the normal power frequency. By changing the frequency parameter of the test signal, the system can detect short circuits without interfering with the stable voltage transmission of the normal power, resolving the contradiction between detection capability and voltage stability.

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

Enables quick detection of short circuits in the bypass switch system during the converter supply mode, ensuring operational safety and preventing voltage exceeding issues.

Implementation Method 1

generating a diagnostic voltage in a power connection of the load supply converter system connected to the load, wherein the diagnostic voltage is different from a voltage of the primary alternating current supply

Methodology Applied
Scientific EffectVoltage difference: Electric Field

Data Source

PatentEP3859937B1Power supply assembly
Publication Date: 2022.06.08 ABB (SCHWEIZ) AG
  • EP3859937B1 patent drawingFigure 1

AI summary

A power supply assembly comprising a load supply converter system (8) and energy saving transfer route (457) both connected electrically to a load connection (71). The energy saving transfer route (457) bypasses the load supply converter system (8), and comprises a bypass switch system (5) having a first bypass switch (51) and second bypass switch (52) connected in series. A control system (909) of the power supply assembly is adapted to provide a system diagnostic operation comprising providing a diagnostic state for the bypass switch system (5) by controlling the first bypass switch (51) into a non-conducting state, and controlling the second bypass switch (52) into a conducting state, generating a diagnostic voltage in an output of the load supply converter system (8), and detecting a short circuit incident if an electric current flowing through the bypass switch system (5) exceeds a predetermined short circuit threshold value.