Rectifier Drive Voltage Control for Variable-Frequency Power Loss
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Solution Overview
Problem
In synchronous rectification circuits, the dynamic power consumption change amplitude of the drive circuit for rectifier transistors is increased when operating at variable frequencies, leading to higher design complexity and difficulty in power supply circuit design due to the high conducted power consumption of rectifier diodes and the transition from wave-off to complementary wave transmission modes.
Innovation Solution
A drive circuit system comprising a processing unit to determine the current wave transmission mode of the rectifier transistor and send a signal to a control unit, which determines an output voltage to supply power to a drive unit, thereby reducing dynamic power consumption change amplitude by adjusting voltage values based on the wave transmission mode, such as between complementary and rectification slow-spread wave transmission modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the rectifier transistor operates in rectification slow-spread wave transmission mode with twice the frequency of complementary wave transmission mode, then the output voltage stability is improved during soft start phase, but the dynamic power consumption of the drive circuit doubles
Solution Approach 1:
The patent applies dynamics by making the drive circuit's power supply voltage adjustable based on the operating mode. The control unit dynamically changes the power supply voltage to the drive unit according to whether the rectifier transistor is in complementary wave transmission mode or rectification slow-spread wave transmission mode, thereby adapting the power consumption to the actual operational requirements and reducing unnecessary energy waste.
Solution Approach 2:
The patent changes the parameter of power supply voltage to the drive circuit based on the wave transmission mode. By adjusting the voltage level according to the operating mode (full bridge or half bridge), the system optimizes the balance between output stability and power consumption, reducing the dynamic power consumption while maintaining the required output voltage stability during soft start phase.
2Adaptability or versatility
If the drive circuit supports variable frequency operation for the rectifier transistor, then the adaptability of the power supply circuit is improved, but the design complexity and difficulty of the power supply circuit increases
Solution Approach 1:
The patent achieves universality by designing a power supply circuit that can operate in multiple wave transmission modes (complementary wave and rectification slow-spread wave modes) with different frequencies. The control unit universally handles both full bridge and half bridge modes, providing a multi-functional solution that reduces design complexity while maintaining adaptability to variable frequency operations.
Solution Approach 2:
The patent applies dynamics by enabling the power supply circuit to dynamically adapt to different operating modes and frequency requirements. The control unit adjusts the power supply voltage in real-time based on the detected wave transmission mode, allowing the circuit to handle variable frequency operations without requiring separate dedicated circuits for each mode, thereby reducing overall design complexity.
3Loss of energy
If synchronous rectification technology is used to replace rectifier diode with transistor, then the power efficiency is improved, but the drive circuit power consumption becomes more sensitive to frequency changes
Solution Approach 1:
The patent changes the parameter of drive circuit power supply voltage based on the operating mode to compensate for the increased sensitivity to frequency changes. By adjusting the voltage level according to whether the system is in complementary wave or rectification slow-spread wave mode, the patent optimizes the drive circuit's power consumption characteristics while maintaining the low conducted power consumption advantage of synchronous rectification.
Solution Approach 2:
The patent implements feedback by having the control unit detect the current wave transmission mode and adjust the power supply voltage accordingly. This closed-loop approach allows the system to respond to frequency changes and mode transitions, optimizing the drive circuit power consumption while maintaining the efficiency benefits of synchronous rectification technology.
Data Source
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AI summary
Embodiments of this application provide a drive circuit system, including a processing unit, a control unit, and a drive unit. The processing unit is configured to determine a current wave transmission mode of a rectifier transistor, and send a first signal based on the current wave transmission mode of the rectifier transistor. The control unit is configured to receive the first signal, and determine a first output voltage based on the first signal, where the first output voltage is used to supply power to the drive unit. The drive unit is configured to drive the rectifier transistor. Based on the foregoing technical solution, when the rectifier transistor works in a variable frequency state, dynamic power consumption change amplitude of a drive circuit of the rectifier transistor can be reduced. This can reduce design difficulty and complexity of a power supply circuit of the drive circuit of the rectifier transistor.