Bidirectional DC-DC Converter Voltage Clamp Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bidirectional DC-DC converters face inefficiencies due to circulating current losses and surge voltages, requiring increased breakdown voltage and apparatus size to maintain performance.
Innovation Solution
An isolated bidirectional DC-DC converter design incorporating a voltage clamp circuit with a series unit of a switching device and reverse parallel diode, along with a current doubler synchronous rectifier circuit and a transformer with a center tap, to reduce circulating currents and prevent surge voltages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a conventional bidirectional DC-DC converter is used, then power conversion between high and low voltage DC sources is achieved, but circulating current losses occur and efficiency is reduced
Solution Approach 1:
The patent extracts and eliminates the circulating current path from the converter circuit by using a center-tapped transformer configuration and synchronized rectification, where the secondary side rectifier switches are turned on at the same time as the primary side switches, preventing the formation of circulating current loops that cause energy losses
Solution Approach 2:
The patent applies preliminary action by pre-synchronizing the rectifier switch timing with the inverter switch timing before power conversion occurs, ensuring that rectifier switches are already in the correct state to prevent circulating current when the inverter switches are activated
2Power
If buck mode operation is implemented, then power transfer from high voltage to low voltage is achieved, but surge voltage is generated on the low voltage side
Solution Approach 1:
The patent applies beforehand cushioning by using the center-tapped transformer configuration and synchronized rectification to preemptively suppress voltage surges before they occur, where the center tap provides a reference potential that stabilizes the low voltage side during buck mode operation
Solution Approach 2:
The center tap of the transformer acts as an intermediary element that mediates the voltage transfer between high and low voltage sides, providing a stable reference point that prevents surge voltage generation during power conversion
3Object-affected harmful factors
If breakdown voltage of switching devices is increased to handle surge voltage, then surge resistance is improved, but apparatus size is enlarged
Solution Approach 1:
The patent converts the potential harmful surge voltage into a beneficial controlled voltage transition by using synchronized rectification, where the rectifier switches are turned on at the same time as inverter switches, transforming what would be a damaging voltage spike into a controlled power transfer mechanism
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 solution effectively minimizes losses and surge voltages, enabling efficient and compact power conversion between high and low voltage DC power sources.
Implementation Method 1
a transformer for transferring power between DC power sources at different voltages
Implementation Method 2
a voltage clamp circuit including a series unit of a switching device with a reverse parallel diode and a capacitor
Data Source
AI summary
The DC-DC converter connects a first and a second switching circuit for converting power mutually between direct current and alternating current respectively to a first DC power source and a second DC power source and has a transformer between the AC terminals thereof. Here, between the AC terminals of the second switching circuit and the negative pole terminal of the DC power source, a voltage clamp circuit composed of a series unit of switching devices with a reverse parallel diode and a clamp condenser is connected.An isolated bidirectional DC-DC converter which prevents a reduction in a circulating current at time of buck and an occurrence of a surge voltage at time of voltage boost and realizes highly efficiency, low noise, and miniaturization is provided.