Power Semiconductor Gate Driving With Dynamic Off-Resistance

Solution Overview

Problem

Conventional gate driving apparatuses for power semiconductor devices have high off-resistor capacity, leading to slow switching and increased turn-off loss due to excessive resistance when turning off the device, which reduces overall efficiency.

Innovation Solution

A gate driving apparatus with a first and second off-resistor, an electric current detector, and a controller that determines the connection state of the second off-switch based on the gate driving signal and detected current magnitude, allowing an additional off-resistor to be connected in parallel with the first off-resistor to reduce total off-resistance and facilitate faster switching.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a large capacity off-resistor is used to ensure safe operation across a wide range of currents, then reliability is improved, but switching speed deteriorates and turn-off loss increases

Engineering Contradiction:

Improvesafe operationVSAvoidswitching speed

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The off-resistor function is segmented into two separate resistors: a first off-resistor with large capacity for safe operation and a second off-resistor with small capacity for fast switching. These are selectively connected to the gate through switches, allowing the system to divide the single resistor function into multiple specialized components that can be activated based on operational requirements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The off-resistor configuration is made dynamic by using switches to selectively connect either the first off-resistor, the second off-resistor, or both in parallel. This dynamic reconfiguration allows the system to adapt the total off-resistor capacity based on the required operation mode, transitioning from a static single-resistor design to a dynamic multi-resistor system.

Inventive Principle:

Principle #15Dynamics

2Reliability

If a large capacity off-resistor is used, then safe operation is ensured, but turn-off loss increases due to excessive resistance

Engineering Contradiction:

Improvesafe operationVSAvoidturn-off loss

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The off-resistor function is segmented into two separate resistors: a first off-resistor with large capacity for safe operation and a second off-resistor with small capacity for fast switching. These are selectively connected to the gate through switches, allowing the system to divide the single resistor function into multiple specialized components that can be activated based on operational requirements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The total off-resistor capacity parameter is changed dynamically by selectively connecting resistors with different capacities. When the second off-resistor is connected in parallel with the first, the total capacity decreases, enabling faster discharge of gate charge and reducing turn-off loss while maintaining safe operation when needed.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If a single off-resistor with large capacity is used, then device complexity is reduced, but switching performance deteriorates

Engineering Contradiction:

Improvecircuit simplicityVSAvoidswitching performance

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The off-resistor function is segmented into two separate resistors: a first off-resistor with large capacity for safe operation and a second off-resistor with small capacity for fast switching. These are selectively connected to the gate through switches, allowing the system to divide the single resistor function into multiple specialized components that can be activated based on operational requirements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The off-resistor circuit is given multi-functionality by enabling it to operate in multiple modes: using only the first off-resistor for safe operation, using only the second off-resistor for fast switching, or using both in parallel for balanced performance. This universal design allows a single circuit configuration to handle diverse operational requirements.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS10756718B2Gate driving apparatus for power semiconductor device

Publication Date: 2020.08.25 HYUNDAI MOTOR CO LTD

AI summary

A gate driving apparatus for a power semiconductor device may include: a first off-resistor and a second off-resistor each having a first end connected to a gate of the power semiconductor device; a first off-switch configured to determine a connection state between a second end of the first off-resistor and a ground based on a gate driving signal for determining an on/off state of the power semiconductor device; a second off-switch configured to determine a connection state between a second end of the second off-resistor and the ground; an electric current detector configured to detect an electric current flowing from a collector (drain) of the power semiconductor device to an emitter (source) of the power semiconductor device; and a controller configured to determine an open/closed state of the second off-switch based on the gate driving signal and a magnitude of the electric current detected by the electric current detector.