Switching Power Converter Charge Pump Drive Circuit Leakage Inductance Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional switching power converters face significant power loss due to leakage inductance, especially in small transformers with high switching frequencies, leading to inefficiency and potential stress on transistors from surge voltages.
Innovation Solution
The implementation of a specific circuit configuration involving multiple transistors, diodes, and a charge pump circuit, along with a switching control circuit that generates tailored switching signals to manage energy transfer and minimize leakage inductance power loss through soft switching techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the switching frequency is increased to improve productivity, then the power loss from leakage inductance increases significantly
Solution Approach 1:
The patent captures the energy that would normally be lost as heat in the leakage inductance and redirects it through a recovery circuit. The leakage inductance energy is transferred to a recovery capacitor and then reused to supply the drive circuit, converting what was harmful power loss into a useful energy source for driving the switching transistor.
Solution Approach 2:
Instead of dissipating the leakage inductance energy through a snubber circuit (which wastes the energy as heat), the patent recovers this energy by directing it through a diode to a recovery capacitor. This recovered energy is then reused to power the drive circuit, effectively recovering what would otherwise be discarded energy.
2Volume of moving object
If a small transformer is used to reduce device size, then the leakage inductance increases leading to higher power loss
Solution Approach 1:
The patent converts the harmful effect of high leakage inductance (which is inevitable in small transformers) into a beneficial resource. The leakage energy that would normally be lost is captured and reused to drive the switching transistor, allowing small transformers to operate efficiently without the power loss penalty.
Solution Approach 2:
The system becomes self-sufficient by using its own leakage inductance energy to power the drive circuit. The recovered energy from the transformer's leakage inductance directly supplies the drive circuit, creating a self-service mechanism that eliminates the need for additional power supply components.
3Reliability
If a traditional snubber circuit is used to handle leakage inductance energy, then power is consumed without recovery
Solution Approach 1:
The patent replaces the traditional snubber circuit that discards energy as heat with a recovery circuit that captures and stores the leakage inductance energy in a capacitor. This recovered energy is then reused to power the drive circuit, transforming a energy-wasting protection mechanism into an energy-recovering system.
Solution Approach 2:
The circuit component that handles leakage inductance energy serves dual functions: it protects the transistor from voltage spikes (traditional snubber function) and simultaneously recovers energy to power the drive circuit. This multi-functionality eliminates the need for separate protection and power supply circuits.
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 significantly reduces power loss associated with leakage inductance, enhancing efficiency and reducing stress on components, particularly in high-frequency switching power converters with small transformers.
Implementation Method 1
A charge pump circuit is connected to the drive circuit to provide a power source to the drive circuit
Implementation Method 2
A transistor 5 is connected to the primary winding NP of a transformer 40 for switching the transformer 40. The secondary winding NS of the transformer 40 thus generates a power source
Implementation Method 3
The secondary winding NS of the transformer 40 thus generates a power source coupled to the output of the switching power converter through a rectifier-and-filter 50
Data Source
AI summary
A switching power converter having a first and a second transistor are connected in series with the transformer to provide higher switching efficiency. A charge pump circuit is coupled to a drive circuit to provide a power source for driving the first transistor. A third transistor is connected between the transformer and the ground to help the switching of the transformer and the charge of the charge pump circuit. A switching control circuit is coupled to the output of the switching power converter to generate a first switching signal and a second switching signal for regulating the switching power converter. The first switching signal is coupled to drive the first transistor and the second transistor. The second switching signal is coupled to drive the third transistor.