Active Voltage Sensing for Bidirectional Switch Dead Time Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing switching converters are bulky, inefficient in energy use, and generate excessive heat, limiting their compactness and reliability, especially in high-power applications.

Innovation Solution

The design incorporates bidirectional switches with high electron mobility transistors (HEMTs) and an advanced control circuit that employs active voltage sensors and a logic circuit to implement zero-voltage switching (ZVS) and optimized dead time management, reducing energy losses and heat generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If conventional switching converters are used, then they can provide voltage conversion, but they are bulky and have large footprint

Engineering Contradiction:
Improveconverter sizeVSAvoidcompactness
Core Design Contradiction:
Volume of moving objectVSReliability

Solution Approach 1:

The patent applies parameter changes by transitioning from conventional MOSFETs to HEMT switches, which fundamentally change the electrical parameters (electron mobility, on-resistance, switching speed) of the switching element. This enables smaller magnetic components and reduced overall converter size while maintaining or improving reliability in compact designs

Inventive Principle:
Principle #35Parameter changes

2Use of energy by moving object

If conventional switching converters are used, then they can perform power conversion, but they are inefficient in energy use

Engineering Contradiction:
Improveenergy efficiencyVSAvoidenergy losses
Core Design Contradiction:
Use of energy by moving objectVSLoss of energy

Solution Approach 1:

The patent implements feedback through active voltage sensing that continuously monitors the voltage across switches and provides real-time information to the control logic. This enables precise zero-voltage switching detection and adjustment, minimizing switching losses and improving overall energy efficiency by adapting switching timing based on actual voltage conditions

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The transition to HEMT switches changes the electrical parameters of the switching device, providing lower on-resistance and faster switching speeds. This reduces both conduction losses and switching losses, significantly improving energy efficiency and reducing total energy losses in the converter

Inventive Principle:
Principle #35Parameter changes

3Temperature

If conventional switching converters are used, then they can provide voltage conversion, but they generate excessive heat

Engineering Contradiction:
Improveheat productionVSAvoidreliability
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent changes the thermal parameters by using HEMT switches with lower on-resistance compared to conventional MOSFETs. This reduction in resistance directly decreases I²R losses during conduction, generating less heat and improving reliability in high-power applications where thermal management is critical

Inventive Principle:
Principle #35Parameter changes

4Loss of energy

If zero-voltage switching control is implemented, then energy efficiency is improved, but device complexity increases

Engineering Contradiction:
Improveswitching lossesVSAvoidcontrol circuit complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The patent applies self-service by using the converter's own voltage conditions to generate the control signals needed for zero-voltage switching. The active voltage sensors detect the natural voltage zero-crossings of the circuit, and the control logic automatically adjusts switching timing based on these detected conditions, eliminating the need for external complex control circuits or additional timing components

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3836374B1Electronic device for the control of a bidirectional switch
Publication Date: 2024.11.13 COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
  • EP3836374B1 patent drawingFigure 1~2
  • EP3836374B1 patent drawingFigure 3
  • EP3836374B1 patent drawingFigure 4

AI summary

This description relates to a control circuit (302) for two electrically series connected switches (210-1, 210-2), comprising voltage sensors (310-1, 310-2) across the switches and a signal comparison circuit (320) for signals supplied by said sensors, at least one of said sensors being an active circuit.