Semiconductor Protection Circuit for Voltage Source Converters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Voltage source converters in power converting apparatuses are vulnerable to damage from fault currents generated by DC side short circuits, leading to ineffective power conversion and potential circuit damage.
Innovation Solution
Incorporating a semiconductor protection circuit with semiconductor switches and diodes in a half-bridge configuration, connected in parallel to converter arms, to divert and manage overcurrents during short circuits, thereby protecting the converter arms and preventing damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If voltage source converters are connected in series for high voltage and high current power conversion, then power conversion capability is improved, but vulnerability to fault current damage increases
Solution Approach 1:
A semiconductor protection circuit is introduced as an intermediary component between the converter arm and the DC circuit. This protection circuit includes semiconductor switches that can be controlled to divert fault current away from the converter arm when a short circuit occurs on the DC side, thereby protecting the converter while maintaining the series connection configuration for high power conversion capability
2Productivity
If converter arms are used for power conversion between AC and DC, then power conversion efficiency is improved, but circuit damage risk increases during DC side short circuits
Solution Approach 1:
The semiconductor protection circuit is configured in parallel with the converter arm and includes semiconductor switches that can be activated in advance or immediately upon detection of a DC side short circuit. This preliminary protective measure creates an alternative current path before the fault current can damage the converter circuit, allowing the converter to maintain high efficiency operation during normal conditions while being protected during fault conditions
Data Source
Figure 1
Figure 2(a)~2(b)
Figure 3(a)~3(b)
AI summary
Disclosed is a power converting apparatus capable of protecting a voltage source converter in the event of a short circuit in a power converting apparatus using a plurality of voltage source converters. The power converting apparatus comprises a semiconductor protection circuit connected in parallel to a converter arm unit including a plurality of voltage source converters, thus enabling overcurrent generated in the event of a short circuit to flow through the semiconductor protection circuit.