Totem-Pole Circuit Control for AC/DC Source Detection and Mode Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power converters struggle to efficiently switch between DC and AC while ensuring system stability and reliability, complicating the design and selection of converter products in AC/DC hybrid systems.
Innovation Solution
A totem-pole circuit with specific control logic that adjusts its working mode based on input/output configuration and node connection state, enabling compatibility with both AC and DC power supplies by operating in power factor correction mode for AC and multiple DC input modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional power converters are used in AC/DC hybrid systems, then the system can operate with mature infrastructure, but the converter cannot efficiently switch between DC and AC modes, increasing device complexity
Solution Approach 1:
The totem-pole circuit is designed to perform multiple functions by detecting input voltage characteristics and automatically switching between power factor correction mode (for AC input) and DC input modes (for DC input). This single circuit structure replaces what would traditionally require separate AC and DC converters, achieving multi-functionality without proportionally increasing complexity
Solution Approach 2:
The circuit employs dynamic operation by continuously monitoring input voltage characteristics and adjusting its working mode accordingly. The controller dynamically switches between different operating states (PFC mode for AC, various DC modes for DC input) based on real-time voltage detection, enabling the system to adapt to changing power supply conditions without manual intervention
2Reliability
If separate AC and DC converters are used to ensure reliable switching between power sources, then system stability is improved, but the number of components and design complexity increase
Solution Approach 1:
The patent merges the functionality of separate AC and DC converters into a single totem-pole circuit structure. By combining multiple operating modes (PFC mode for AC, multiple DC input modes) into one unified circuit, the design eliminates the need for separate converter units while maintaining reliable operation during power source transitions
Solution Approach 2:
The circuit incorporates feedback mechanisms through voltage detection that continuously monitors input characteristics and provides information to the controller. This feedback loop enables automatic mode selection and switching, ensuring stable operation during transitions between AC and DC power sources without requiring complex external control systems or multiple independent converters
Data Source
Figure 1A~1B
Figure 2~3
Figure 4~6
AI summary
A totem-pole circuit includes switching devices Q1, Q2, Q3, Q4 and an inductor. A fifth node between Q1 and Q2 is coupled to a third node. A sixth node between Q3 and Q4 is coupled to a fourth node, at least one of the fifth and sixth nodes being coupled to a respective node of the third and fourth nodes via the inductor. An input voltage between the third and fourth nodes is obtained in a forward input configuration of the totem-pole circuit. Based on the input voltage, whether the third and fourth nodes are connected to AC or DC power supply is determined. The totem-pole circuit operates in a PFC mode upon being connected to the AC power supply. A working mode of the totem-pole circuit is selected from a plurality of DC input modes upon being connected to the DC power supply.