DC-DC Converter with Segmented Mode Switching for Transient Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional DC-DC converters, such as the KY converter, have limitations including inability to function as both step-up and step-down converters, poor transient load response due to right-hand zero in transfer functions, and inability to decouple input and output voltages when switches are off.
Innovation Solution
The proposed converter design includes switches S1, S2, and S3 with an inductor L1 and capacitors C1 and C2, allowing for adjustable output voltage between 0 and 2*VIN by controlling switch operations and duty cycles, enabling both step-up and step-down functionality and improved transient load response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a boost circuit is used in the converter, then output voltage ripple and noise are reduced, but transient load response performance deteriorates due to right-hand zero in transfer function
Solution Approach 1:
The converter is divided into two distinct operational modes (first mode and second mode) with different circuit configurations. In the first mode, the circuit operates as a boost converter for step-up conversion. In the second mode, the circuit reconfigures for buck conversion. This segmentation allows the system to achieve low ripple and noise in each mode while providing fast transient response through mode switching.
Solution Approach 2:
The converter employs dynamic reconfiguration of circuit elements through controlled switching of switches between first and second modes. The duty cycle is dynamically adjusted based on whether step-up or step-down conversion is required. This dynamic operation eliminates the fixed right-hand zero characteristic of conventional boost circuits and enables fast transient load response.
2Object-affected harmful factors
If the KY converter topology is used, then output voltage ripple is reduced and load response is improved, but the converter can only function as step-up and not step-down
Solution Approach 1:
The converter is designed with universal functionality to operate in both step-up (boost) and step-down (buck) modes. By controlling the switching sequence and duty cycle of the switches, the same circuit topology can achieve voltage conversion in both directions. The first mode provides boost conversion when output voltage exceeds input voltage, while the second mode provides buck conversion when output voltage is less than input voltage.
Solution Approach 2:
The converter dynamically switches between two operational modes to achieve both step-up and step-down functionality. The control circuit adjusts the duty cycle and switching sequence based on the required conversion direction. This dynamic reconfiguration enables a single converter design to replace what would traditionally require separate boost and buck converters.
3Loss of energy
If switches are turned off in the KY converter, then switching losses are reduced, but input and output voltages cannot be decoupled
Solution Approach 1:
The converter separates the input and output voltage paths through distinct circuit configurations in different modes. In the first mode, the input voltage is coupled to the output through the boost configuration. In the second mode, the circuit reconfigures to provide buck conversion with different coupling paths. This segmentation allows for better isolation and decoupling of input and output voltages when switches are in off states, improving reliability.
4Device complexity
If the output voltage range is limited to VIN to 2*VIN in KY converter, then circuit complexity is reduced, but adaptability for different voltage requirements is limited
Solution Approach 1:
The converter achieves universal voltage conversion capability with output voltage ranging from 0 to 2*VIN using the same circuit topology. By controlling the duty cycle and switching mode, the converter can provide buck conversion (0 to VIN) and boost conversion (VIN to 2*VIN). This eliminates the need for different circuit topologies for different voltage ranges while maintaining adaptability to various voltage requirements.
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 provides enhanced transient load response and voltage control, allowing the converter to function as both step-up and step-down converter, with faster inductor current rise rates compared to conventional buck converters, effectively addressing the limitations of existing designs.
Implementation Method 1
a third switch S3 electrically coupled to the input port 101 at one terminal and coupled to the output port 102 via an inductor L1 at the other terminal; the inductor L1 electrically coupled between the other terminal of the third switch S3 and the output port 102
Implementation Method 2
a first capacitor C1 electrically coupled between the first switch S1 and the third switch S3; an output capacitor C2 electrically coupled between the output terminal and ground
Data Source
AI summary
Power converters and associated methods of operation are disclosed herein. In one embodiment, a power converter includes a first switch and a second switch electrically coupled to the first switch in series. The first switch is electrically coupled to a first node and to a second node via the second switch. The power converter further includes a capacitor and a third switch electrically coupled to the first node and to the second node via the capacitor and the second switch. The third switch has a linear-active region of operation.