Bridge Circuit Charge Recycler Reduces Switching Losses

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing bridge circuits and rectifiers face challenges in reducing power consumption during switching operations due to high conduction and switching losses, particularly when using large switching devices that increase parasitic capacitance and on-resistance.

Innovation Solution

The implementation of a bridge circuit with charge recyclers and a controller that transfers charges accumulated in switching devices to their gates before turning them on, using charge transfer switching devices and capacitors to reduce switching losses and power consumption, and controlling the switching devices based on current flow to optimize their operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If large switching devices are used in bridge circuits, then power handling capability is improved, but parasitic capacitance and on-resistance increase causing higher power consumption

Engineering Contradiction:

Improvepower handling capabilityVSAvoidpower consumption

Core Design Contradiction:

PowerVSUse of energy by moving object

Solution Approach 1:

The patent converts the harmful parasitic capacitance and stored charge in switching devices into a beneficial resource by recycling these charges to assist in turning on subsequent switching devices. The charge recycler captures charge from switching devices being turned off and uses it to reduce the gate drive power needed for switching devices being turned on, thereby converting what was previously wasted energy into useful energy that reduces overall power consumption.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent changes the electrical parameters (charge and voltage) of the switching devices by introducing a charge recycler circuit. This circuit actively modifies the charge state of switching devices by transferring charge between them, thereby changing their electrical characteristics to reduce power consumption while maintaining their power handling capability.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If switching devices are turned on frequently, then rectification efficiency is improved, but switching losses increase power consumption

Engineering Contradiction:

Improverectification efficiencyVSAvoidswitching losses

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The patent converts the energy loss occurring during switching operations into a beneficial resource. By capturing the charge that would normally be lost when switching devices turn off and recycling it to assist in turning on subsequent devices, the system converts switching losses into useful energy that reduces overall power consumption while maintaining high rectification efficiency.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The charge recycler maintains continuous operation by constantly recycling charge between switching devices. This continuous charge transfer ensures that energy is consistently reused across multiple switching cycles, reducing switching losses continuously while maintaining high rectification efficiency without interruption.

Inventive Principle:

Principle #20Continuity of useful action

3Use of energy by moving object

If charge is transferred between switching devices, then power consumption is reduced, but circuit complexity increases

Engineering Contradiction:

Improvepower consumptionVSAvoidcircuit complexity

Core Design Contradiction:

Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The charge recycler circuit performs multiple functions: it captures charge from switching devices, stores the captured charge, and transfers it to assist in turning on subsequent switching devices. This multi-functionality allows a single circuit block to handle charge recycling operations, reducing the need for separate circuits and thereby limiting the increase in overall system complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The charge recycler acts as an intermediary circuit between switching devices, mediating the charge transfer process. This intermediary structure simplifies the overall system architecture by providing a dedicated charge management interface, making the charge recycling function modular and easier to integrate without proportionally increasing overall circuit complexity.

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 approach reduces switching losses by reusing energy stored in parasitic capacitors, minimizing the power required to turn on switching devices and lowering overall power consumption, while maintaining efficient operation.

Implementation Method 1

a capacitor connected between the third node and the ground

Methodology Applied

Scientific EffectCapacitance: Capacitance

Data Source

PatentUS10547249B2Bridge circuit and rectifier including the same

Publication Date: 2020.01.28 SAMSUNG ELECTRO MECHANICS CO LTD

AI summary

A bridge circuit includes: a first leg including a first switching device and a second switching device connected between a first node and a ground; a second leg including a third switching device and a fourth switching device connected between the first node and the ground; and a first charge recycler connected between a gate of the first switching device and a gate of the third switching device, and configured to transfer charges accumulated in the first switching device to the gate of the third switching device prior to turning on the third switching device.