Reconfigurable On-Board Charger Circuit for High-Power Single-Phase Input
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing single/three-phase compatible on-board chargers have low charging power during single-phase input, failing to meet the increasing demand for high-power charging.
Innovation Solution
An on-board charger design featuring a power supply terminal with a switching circuit and bridge arms, controlled by a circuit that adjusts operation based on single-phase or three-phase power supply, reducing the number of bus capacitors during single-phase input to enhance charging power and reduce volume and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single/three-phase compatible on-board charger is designed with conventional circuit topology, then the charger can support both single-phase and three-phase inputs, but the charging power is limited to 6.6 KW during single-phase input
Solution Approach 1:
The patent applies dynamics by making the circuit topology reconfigurable through switching elements. The charger dynamically changes its internal connection structure based on whether single-phase or three-phase input is detected, allowing it to optimize the power conversion path for each mode. This dynamic reconfiguration enables the system to achieve 6.6KW in single-phase mode and higher power in three-phase mode, resolving the contradiction between compatibility and power output.
Solution Approach 2:
The patent changes the electrical parameters of the circuit by using switchable bridge arm configurations. By altering the connection topology through controlled switching, the system changes effective impedance, voltage utilization, and current paths. This parameter change allows the same hardware to deliver different power levels depending on the input phase configuration, thereby increasing charging power during single-phase input while maintaining compatibility.
2Power
If the charging power is increased to meet high-power requirements, then the charging speed and user satisfaction improve, but the volume and cost of the charger increase
Solution Approach 1:
The patent implements multi-functionality by designing a single charger unit that can operate in multiple power modes (single-phase 6.6KW and three-phase high power). The same physical hardware performs different functions depending on the input configuration, eliminating the need for separate chargers for different power requirements. This universal design increases charging power capability without proportionally increasing volume, as the system adapts its power output based on the detected input type.
Solution Approach 2:
The dynamic reconfiguration capability allows the charger to achieve high power output only when needed (three-phase input), while maintaining a compact form factor for single-phase operation. The switching mechanism enables the system to dynamically adjust its power handling capacity, ensuring high charging power is available on demand without permanently increasing the charger's volume to accommodate the maximum possible power rating.
3Power
If more bus capacitors are used to support high-power operation, then the power delivery capability improves, but the volume and cost of the charger increase
Solution Approach 1:
The patent uses dynamic switching to activate different bridge arm configurations based on the input phase type. During single-phase operation, only the necessary subset of bridge arms and associated capacitors are activated, reducing the effective number of capacitors in the circuit. This dynamic activation allows the system to maintain high power delivery capability when needed while minimizing the actual capacitor count in use, thereby reducing volume and cost compared to a design that always provisions for maximum power.
Solution Approach 2:
The system changes the operational parameters of the capacitor network by selectively engaging different capacitor sets based on input configuration. Instead of always using all capacitors, the system adjusts the effective capacitance in the circuit to match the power requirements of the current operating mode. This parameter adjustment allows adequate power delivery for each mode without requiring the full complement of capacitors to be physically present and occupied in the design.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The present disclosure provides an on-board charger including a power supply terminal, a switching circuit, a first bridge arm, a second bridge arm, a third bridge arm, a fourth bridge arm, a first bus capacitor, a second bus capacitor, a first switch and a control circuit. The present disclosure can realize a compatibility of a single-phase power supply input or a three-phase power supply input through the cooperation of the switching circuit with the control circuit. Meanwhile, the number of bus capacitors is reduced in the operating state of the single-phase power supply input, accordingly not only the volume and cost of the on-board charger can be reduced, but also the charging power of the on-board charger can be increased, which has an advantage of strong applicability.