Resonant Capacitor Balancing Circuit for Stable Voltage Conversion
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Solution Overview
Problem
Conventional conversion circuits for AI chip power supplies suffer from voltage imbalance and lack of closed-loop control, making them difficult to implement slow startup and overcurrent protection.
Innovation Solution
A conversion circuit with a capacitor module, balancing module, and startup module, utilizing resonant circuits and switches to balance capacitor voltages and achieve different transformation ratios, incorporating a closed-loop mechanism for stable output voltage and slow startup.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional conversion circuit with capacitors in equivalent serial connection is used, then the circuit structure is simple, but voltage imbalance occurs after long-time operation
Solution Approach 1:
The capacitor module is divided into multiple independent capacitor units (first capacitor, second capacitor, third capacitor) that can be independently controlled and managed. Each capacitor can be individually balanced through the resonant circuit, preventing voltage imbalance across the entire module while maintaining structural simplicity.
Solution Approach 2:
The resonant circuit establishes a feedback mechanism that continuously monitors and adjusts capacitor voltages. By controlling the switches to enable resonant energy exchange between capacitors, the circuit automatically balances voltage distribution, ensuring long-term reliable operation without complex additional control circuits.
2Loss of energy
If a resonant switched capacitor solution is used, then power conversion efficiency is improved, but closed-loop control and slow startup are difficult to implement
Solution Approach 1:
The resonant circuit is integrated with a closed-loop control mechanism that monitors output voltage and adjusts switch conduction accordingly. This feedback system enables precise control of the resonant energy transfer, achieving both high efficiency and stable regulated output voltage with slow startup capability.
Solution Approach 2:
The resonant circuit acts as an intermediary energy transfer mechanism between input and output. By using the resonant oscillation as a controlled intermediate step, the circuit achieves smooth energy transfer with inherent soft-start characteristics, avoiding direct switching transients while maintaining efficiency.
3Reliability
If capacitor voltage balancing is implemented through resonant circuit, then voltage balance is achieved, but circuit complexity increases
Solution Approach 1:
The resonant circuit serves multiple functions simultaneously: it transfers energy between capacitors, balances voltages across capacitor units, provides closed-loop control capability, and enables slow startup. This multi-functionality achieves voltage balancing without adding separate dedicated circuits for each function.
Solution Approach 2:
The voltage balancing function is merged with the energy transfer function in a single resonant circuit structure. The same resonant oscillation that transfers energy also equalizes capacitor voltages, eliminating the need for separate balancing circuits and reducing overall system complexity.
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
The circuit effectively balances capacitor voltages, achieves stable output voltage, and enables slow startup while providing overcurrent protection, enhancing power conversion efficiency and reliability.
Implementation Method 1
the first capacitor may perform energy transmission with the second capacitor by using the first resonant circuit, thereby balancing voltages at both ends of capacitors
Data Source
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AI summary
A conversion circuit is used to balance voltages at both ends of capacitors, and implement different voltage transformation ratios. The method in embodiments of this application includes a capacitor module, a balancing module, and a startup module. The capacitor module includes at least a first capacitor and a second capacitor. The balancing module includes at least a first resonant circuit. The startup module includes a direct current-direct current converter and a target capacitor. The first resonant circuit includes at least two groups of switches connected in parallel to each other and a first resonant cavity connected between the two groups of switches. The first capacitor is connected in series to the second capacitor, and the first capacitor is connected in parallel to the target capacitor. The first resonant circuit is separately connected to both ends of the first capacitor and the second capacitor by using the startup module. The balancing module balances voltages at both ends of the first capacitor and the second capacitor by controlling the switches in the first resonant circuit in conjunction with influence of the first resonant cavity on a current. The startup module is configured to start the balancing module and the capacitor module.