Configurable DC-DC Converter Topology for Bipolar Step-Up/Step-Down Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern embedded control systems, particularly in aerospace, require DC-to-DC converters that can provide multiple voltage levels and both positive and negative outputs, with the ability to step up or down voltage as needed, which existing technologies struggle to achieve efficiently.
Innovation Solution
A DC-to-DC converter design incorporating five switches, coupled inductors, and a bypass capacitor, operating in both inverting and non-inverting modes, where the controller selectively controls the switches to adjust the duty cycle and achieve voltage stepping up or down based on the desired output voltage, with specific relationships between input and output voltages defined by the duty cycle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a DC-to-DC converter is designed to provide multiple voltage levels and both positive and negative outputs, then the versatility and adaptability of the converter is improved, but the device complexity increases
Solution Approach 1:
The patent implements a single DC-to-DC converter circuit that can operate in multiple modes (buck, boost, inverting) and provide both positive and negative voltage outputs. The converter uses a unified topology with five switches, two coupled inductors, and capacitors that can be controlled to achieve different voltage conversion functions, eliminating the need for separate converters for each voltage level and polarity.
Solution Approach 2:
The converter employs dynamic control of five switches (S1-S5) with adjustable duty cycles to transition between different operating modes. The controller dynamically adjusts the switching patterns and duty cycle ratios to achieve buck operation (D<0.5), boost operation (D>0.5), or inverting mode, allowing the same hardware to adapt to different voltage requirements without physical reconfiguration.
2Adaptability or versatility
If the converter operates in both inverting and non-inverting modes with adjustable duty cycle, then the adaptability to different voltage requirements is improved, but the control complexity increases
Solution Approach 1:
The converter operates using periodic switching of the five switches at a fixed switching frequency. The controller applies periodic square-wave control signals with adjustable duty cycles to switches S1-S5, enabling the converter to achieve different voltage conversion ratios through the duty cycle parameter while maintaining a simple periodic control structure rather than complex continuous control.
Solution Approach 2:
The converter achieves different voltage outputs by changing the duty cycle parameter (D) of the switch control signals. When D<0.5, the converter operates in buck mode with Vout<Vin; when D>0.5, it operates in boost mode with Vout>Vin; and by configuring specific switches in inverting mode, it can also produce negative voltages. This single parameter change controls the entire voltage conversion behavior.
3Adaptability or versatility
If the converter uses five switches and two coupled inductors to achieve voltage stepping up or down, then the voltage conversion capability is improved, but the device complexity and component count increases
Solution Approach 1:
The patent merges the functions of multiple separate voltage conversion circuits into a single unified converter topology. The two coupled inductors share magnetic flux and energy storage, and the five switches work together in coordinated patterns to achieve both buck and boost functions, as well as inverting operation, within one integrated circuit rather than requiring separate converters for each function.
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 converter effectively provides both positive and negative voltage outputs, efficiently stepping up or down the input voltage in both inverting and non-inverting modes, improving electromagnetic interference (EMI) performance and meeting the diverse voltage requirements of modern control systems.
Implementation Method 1
two coupled inductors. The two coupled inductors including a first inductor that has a first end connected to the input and a second end connected to the first end of the bypass capacitor at the first node, the two coupled inductors also including a second inductor that has a first end connected to the second end of the bypass capacitor at the second node and a second end connected to a third node
Implementation Method 2
a bypass capacitor having first end connected to a first node and a second end connected to a second node
Data Source
AI summary
A DC-to-DC converter includes an input configured to receive a DC input voltage, an output having a positive rail and a negative rail, wherein the negative rail is configured for connection to a negative terminal of the DC input voltage source, a bypass capacitor having first end connected to a first node and a second end connected to a second node and two coupled inductors, the two coupled inductors including a first inductor that has a first end connected to the input and a second end connected to the first end of the bypass capacitor at the first node, the two coupled inductors also including a second inductor that has a first end connected to the second end of the bypass capacitor at the second node and a second end connected to a third node. The converter includes switches that allow control of the polarity and magnitude of the output.