Single-Phase Bridge Switching Control via Dynamic Lockout

Solution Overview

Problem

Existing power converter control systems require excessive lockout times to prevent switching element overlap, leading to increased harmonics and delays in the output waveform due to the need to accommodate extreme operating conditions, which results in inefficient operation.

Innovation Solution

A system and method for controlling switching elements in a single-phase bridge circuit by monitoring parameters such as collector-emitter voltage, gate voltage, and current direction to minimize lockout times, allowing for active detection of switching element states and synchronized activation/deactivation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a predetermined lockout time is programmed into the controller to accommodate extreme operating conditions, then switching element damage is prevented, but additional harmonics are introduced and control delay increases

Engineering Contradiction:

Improveswitching element protectionVSAvoidharmonics in output waveform

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies dynamics by transitioning from a static, predetermined lockout time to a dynamic, real-time lockout time. The controller continuously monitors the actual turn-off times of switching elements and adjusts the lockout time accordingly. This allows the lockout time to adapt to varying operating conditions, ensuring sufficient protection while minimizing harmonics and control delay when extreme conditions do not exist.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements feedback by having the controller monitor the actual turn-off times of switching elements and use this information to adjust the lockout time. The controller receives feedback about the real switching behavior and modifies the lockout time to match actual operating conditions, thereby optimizing both protection and waveform quality.

Inventive Principle:

Principle #23Feedback

2Reliability

If a predetermined lockout time is programmed into the controller to accommodate extreme operating conditions, then switching element damage is prevented, but unnecessary delay in switching element control occurs

Engineering Contradiction:

Improveswitching element protectionVSAvoidcontrol delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies dynamics by transitioning from a static, predetermined lockout time to a dynamic, real-time lockout time. The controller continuously monitors the actual turn-off times of switching elements and adjusts the lockout time accordingly. This allows the lockout time to adapt to varying operating conditions, ensuring sufficient protection while minimizing harmonics and control delay when extreme conditions do not exist.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements feedback by having the controller monitor the actual turn-off times of switching elements and use this information to adjust the lockout time. The controller receives feedback about the real switching behavior and modifies the lockout time to match actual operating conditions, thereby optimizing both protection and waveform quality.

Inventive Principle:

Principle #23Feedback

3Ease of manufacture

If the switching elements are controlled with fixed lockout time, then implementation is simple, but the system cannot adapt to varying operating conditions

Engineering Contradiction:

Improvecontrol system implementationVSAvoidadaptation to operating conditions

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent applies dynamics by transitioning from a static, predetermined lockout time to a dynamic, real-time lockout time. The controller continuously monitors the actual turn-off times of switching elements and adjusts the lockout time accordingly. This allows the lockout time to adapt to varying operating conditions, ensuring sufficient protection while minimizing harmonics and control delay when extreme conditions do not exist.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements feedback by having the controller monitor the actual turn-off times of switching elements and use this information to adjust the lockout time. The controller receives feedback about the real switching behavior and modifies the lockout time to match actual operating conditions, thereby optimizing both protection and waveform quality.

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP2854276B1System and method for controlling switching elements within a single-phase bridge circuit

Publication Date: 2021.02.24 GENERAL ELECTRIC CO

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AI summary

A method 600 for controlling the operation of switching elements contained within a single-phase bridge circuit of a power convertor is disclosed that may include monitoring 602 gate voltages of a first switching element and a second switching element of the single-phase bridge circuit and controlling the first and second switching elements so that each switching element is alternated between an activated state and a deactivated state. In addition, the method may include transmitting 608 a gating command signal to adjust the first switching element from the deactivated state to the activated state when: a first gate drive command is received that is associated with switching the first switching element to the activated state; a second gate drive command is received that is associated with switching the second switching element to the deactivated state; and the gate voltage of the second switching element is less than a predetermined voltage threshold.