AC-DC Extraction Converter With Peak Detection and Low Dissipation
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Solution Overview
Problem
Existing AC to DC converter technologies face inefficiencies and bulkiness, making them unsuitable for integration in miniature devices and modern electronics, especially for low voltage applications, and they struggle to achieve high efficiency and compactness required for 'smart' devices and power management systems.
Innovation Solution
The proposed AC to DC power conversion system uses a 'peak detector' circuit with a comparator and series switch to reduce the input voltage to the series regulator, allowing a smaller capacitor to store energy and minimizing power dissipation, thereby increasing efficiency and enabling integration in silicon-based devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a transformer is used in the power conversion circuit, then voltage regulation and isolation are achieved, but the size and weight of the magnetic structure increase significantly
Solution Approach 1:
The patent extracts and eliminates the transformer component from the power conversion circuit, replacing it with a direct rectification approach followed by voltage regulation using solid-state devices. This removal of the magnetic structure achieves voltage regulation without the weight penalty of traditional transformer-based designs.
2Reliability
If a shunt regulator with Zener diode is used, then voltage regulation is achieved, but power efficiency deteriorates due to excessive current dissipation
Solution Approach 1:
The patent introduces an operational amplifier as an intermediary device between the rectified voltage source and the load. The op-amp operates in a feedback configuration with the Zener diode, acting as a buffer that allows the Zener to regulate voltage with minimal current while the op-amp supplies the necessary current to the load, thereby dramatically reducing power dissipation.
3Loss of energy
If a series regulator with active device is used, then power dissipation is reduced compared to shunt regulation, but integration difficulty increases due to component complexity
Solution Approach 1:
The patent merges multiple functions into a single integrated operational amplifier circuit. The op-amp combines the functions of voltage sensing, error amplification, and current control in one component, working with the Zener diode to achieve both low power dissipation and ease of integration. This unified approach reduces the number of discrete components and simplifies the overall circuit architecture.
4Loss of energy
If switch mode power supply is used, then efficiency is improved, but RF noise and conductor losses increase due to high speed switching
Solution Approach 1:
The patent employs periodic action by using the natural frequency of the AC mains input (50/60 Hz) as the basis for its operation. The circuit rectifies and regulates voltage at this low frequency rather than using high-speed switching, thereby achieving efficient power conversion without generating RF noise or suffering from skin effect losses in conductors.
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 solution achieves high efficiency, reduces heat dissipation, and allows for compact, integrated power converters that can be used in a wide range of devices, including those in 'smart' homes and cars, with efficiencies approaching 99-100%.
Implementation Method 1
In the simplest implementation of the shunt regulator, a Zener diode is connected in shunt with the load with a resistor in series with this shunt leg. Any rectifier output voltage in excess of the Zener voltage is dropped across the resistor resulting in the excess power being dissipated as heat.
Implementation Method 2
a filter comprising an electrolytic capacitor and resistor
Data Source
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AI summary
An improved AC direct to DC extraction conversion system is described. The AC direct to DC extraction conversion system consists of an efficient electronic switch employed to provide controlled pulsed power to a storage device. The AC to DC converter in one minimal version consists of a pair of N-MOSFET transistors, a voltage divider, a storage element and a pair of diodes. The design enables high efficiency with minimal components that may be fully integrated onto silicon.