Bidirectional DC-DC Converter Resonant Bypass for Stable Voltage Gain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bidirectional DC-DC converters, such as those described in PTL 1, exhibit non-linear changes in output voltage gain, limiting the range of output voltage and compromising control stability.
Innovation Solution
A bidirectional DC-DC converter is designed with a transformer, bridge circuits for DC-AC conversion, resonant circuits, bypass switches, and a control unit to manage the connection states of the resonant circuits, allowing for the formation of LC resonant circuits on either side of the transformer based on power flow direction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a resonant type DC-DC converter is used to reduce stress on devices and electromagnetic noise, then device stress and electromagnetic noise are reduced, but the output voltage range is limited and control stability is low due to non-linear gain changes
Solution Approach 1:
The patent applies dynamics by making the resonant circuit configuration changeable through bypass switches. The system can dynamically switch between different resonant circuit connection states (connected or disconnected) based on operating conditions, allowing the circuit to adapt to different power flow directions and load conditions. This dynamic reconfiguration enables linearization of the gain characteristics while maintaining the benefits of resonant operation, thereby improving control stability without sacrificing electromagnetic noise reduction.
2Strength
If a resonant type DC-DC converter is used to reduce stress on devices, then device stress is reduced, but the output voltage range is limited due to non-linear gain changes
Solution Approach 1:
The bypass switches enable dynamic reconfiguration of the resonant circuits based on power flow direction and operating conditions. By switching the connection state of resonant circuits, the system can adapt to different voltage requirements and expand the output voltage range while maintaining the low device stress benefits of resonant operation.
Solution Approach 2:
The patent changes the circuit configuration parameters by switching the resonant circuits in and out of the circuit. This parameter change allows the system to adjust its gain characteristics and expand the output voltage range while maintaining the beneficial low-stress operation of resonant converters.
3Reliability
If bypass switches are added to control resonant circuit connection states, then output voltage range and control stability are improved, but device complexity increases
Solution Approach 1:
The bypass switches serve multiple functions: they control the connection state of resonant circuits, enable bidirectional power flow, and provide gain linearization. This multi-functionality reduces the need for separate components and justifies the added complexity by delivering multiple benefits from a single control mechanism.
Solution Approach 2:
The bypass switches provide a simple binary control mechanism (connected/disconnected) that achieves complex control objectives. By changing the connection parameter of the resonant circuits, the system can achieve gain linearization and voltage range expansion without requiring complex control algorithms or additional active components.
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
This configuration enhances the range of output voltage and improves control stability, enabling a bidirectional DC-DC converter with high operational efficiency.
Implementation Method 1
a first resonant circuit connectable between the first bridge circuit and the primary side of the transformer; a second resonant circuit connectable between the second bridge circuit and the secondary side of the transformer
Data Source
AI summary
This bidirectional DC-DC converter comprises: a transformer; a first bridge circuit for converting DC power and AC power to each other which are input and output between a first DC power supply and the primary side of the transformer; a second bridge circuit for converting DC power and AC power to each other which are input and output between a second DC power supply and the secondary side of the transformer; a first resonant circuit connectable between the first bridge circuit and the primary side of the transformer; a second resonant circuit connectable between the second bridge circuit and the secondary side of the transformer; a first bypass switch for switching the connection state of the first resonant circuit between the first bridge circuit and the primary side of the transformer; a second bypass switch for switching the connection state of the second resonant circuit between the second bridge circuit and the secondary side of the transformer; and a control unit for controlling each of the first bypass switch and the second bypass switch.