Variable Inductance Boost Circuit for Wide Input Voltage Range
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing boost circuits face impractical switching losses and limited operational range due to excessive switching frequency at high input voltages, requiring specific design for each voltage range and impractical MOSFET usage.
Innovation Solution
A boost circuit with a variable inductance that changes as a function of input voltage, allowing control over switching frequency by selectively using different inductance values through a controller and mode selection circuit, preventing excessive switching frequency at high input voltages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the boost circuit operates at high input voltage (e.g., 380V) with fixed inductance, then the circuit can handle high voltage input, but the switching frequency becomes excessively high (up to 400 kHz) causing excessive switching loss
Solution Approach 1:
The patent applies dynamics by making the inductance value adjustable based on operating conditions. The boost circuit switches between two inductance values (L1 and L2) depending on the input voltage level. At high input voltages, a larger inductance value is used to reduce the switching frequency and minimize switching losses. At lower input voltages, a smaller inductance value is used to maintain efficient operation. This dynamic adjustment of inductance allows the circuit to adapt to different voltage conditions optimally.
Solution Approach 2:
The patent changes the inductance parameter based on input voltage conditions. By switching between two discrete inductance values, the circuit optimizes its performance across different operating ranges. The controller monitors the input voltage and selects the appropriate inductance value to maintain efficient operation, thereby reducing switching losses at high voltages while preserving adaptability across a wide voltage range.
2Adaptability or versatility
If the boost circuit uses a single fixed inductance value, then the circuit design is simple, but it cannot efficiently operate over a wide range of input voltages due to excessive switching frequency at high voltages
Solution Approach 1:
The patent segments the inductance function into two distinct inductance values (L1 and L2) that can be selectively activated. Instead of using a single fixed inductance or a continuously variable inductance, the circuit divides the operating range and uses appropriate inductance segments for different voltage conditions. This segmentation approach maintains relative simplicity while achieving wide voltage range adaptability.
Solution Approach 2:
The patent implements multi-functionality by making the inductance element capable of serving different functions at different operating conditions. The same inductance circuit structure performs both low-voltage and high-voltage optimization functions by switching between two inductance values. The controller integrates multiple functions: voltage monitoring, inductance selection, and switching control, thereby managing complexity through functional integration.
3Speed
If the boost circuit uses high-frequency MOSFET switching to maintain operation at high input voltages, then the circuit can operate at high voltage, but switching losses become excessive and practical implementation becomes difficult
Solution Approach 1:
The patent applies dynamics by making the inductance value adjustable based on operating conditions. The boost circuit switches between two inductance values (L1 and L2) depending on the input voltage level. At high input voltages, a larger inductance value is used to reduce the switching frequency and minimize switching losses. At lower input voltages, a smaller inductance value is used to maintain efficient operation. This dynamic adjustment of inductance allows the circuit to adapt to different voltage conditions optimally.
Solution Approach 2:
The patent changes the inductance parameter based on input voltage conditions. By switching between two discrete inductance values, the circuit optimizes its performance across different operating ranges. The controller monitors the input voltage and selects the appropriate inductance value to maintain efficient operation, thereby reducing switching losses at high voltages while preserving adaptability across a wide voltage range.
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
Enables efficient operation over a wide range of input voltages by adjusting effective inductance, reducing switching losses and allowing the circuit to operate without the need for high-frequency MOSFET switching, thus extending the operational range of the boost circuit.
Implementation Method 1
a first inductor L1 (having a first inductance) and a second inductor L2 (having a second inductance)
Data Source
AI summary
A boost circuit is used for power factor correction (PFC). In a low power application, transition mode control is utilized. However, switching frequency varies with different input voltages, and over a wide input voltage range, the switching frequency can become too high to be practical. To address this issue, a boost circuit is provided whose effective inductance changes as a function of input voltage. By changing the inductance, control is exercised over switching frequency.