High-Frequency Isolated Power Supply for Reactive Power Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional AC power supplies pose risks of electric shock and inefficiency due to reactive power, especially in environments with increased danger, and existing safety measures are inadequate.
Innovation Solution
A power supply device with a DC-to-AC converter that converts mains AC voltage to a higher frequency (100-500 kHz) output voltage, utilizing a resonant circuit with an inductor and capacitor to reduce reactive power and provide galvanic isolation, along with a control unit to manage the converter frequency and output voltage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional AC power supply is used, then power delivery is simple and direct, but safety risk increases due to electric shock hazard from mains voltage
Solution Approach 1:
The patent introduces a high-frequency transformer as an intermediary device between the mains AC supply and the load. This transformer converts the low-frequency mains voltage to high-frequency voltage, providing galvanic isolation that eliminates direct electric shock hazard while maintaining power delivery functionality. The high-frequency transformer acts as a mediator that transfers energy without direct electrical connection.
Solution Approach 2:
The patent changes the frequency parameter of the AC power supply from conventional 50/60 Hz to high frequency (100-500 kHz). This parameter change fundamentally alters the safety characteristics by enabling galvanic isolation through the high-frequency transformer, while also improving efficiency by reducing reactive power in inductive and capacitive loads.
2Loss of energy
If conventional AC power supply operates inductive and capacitive loads, then power delivery is straightforward, but efficiency deteriorates due to reactive power losses
Solution Approach 1:
The patent changes the operating frequency parameter to high frequency (100-500 kHz), which fundamentally alters the reactive power characteristics of inductive and capacitive loads. At high frequencies, the reactance of inductors increases and capacitors decreases, allowing the system to operate more efficiently by reducing reactive power circulation and improving overall power delivery efficiency.
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
The device significantly reduces the risk of electric shock and improves efficiency by neutralizing reactive resistances and providing galvanic isolation, making it safer and more efficient than conventional AC power supplies.
Implementation Method 1
an output transformer with at least two outputs that galvanically isolates the primary-side converter AC voltage of the DC-to-AC converter into a secondary-side output voltage
Implementation Method 2
a rectifier for rectifying the mains AC voltage that is fed into the input
Implementation Method 3
a resonant circuit, which has the capacitance, the inductance, a secondary winding of the transformer and the load, is operated in such a way that the reactive power is reduced compared to the operation of the load with the mains AC voltage by frequency matching
Data Source
Figure 1
Figure 2a
Figure 2b
AI summary
A safe and efficient power supply device (1) has an input (10) for a mains AC voltage with an input frequency on a primary side of the power supply device (1); a rectifier (3) for rectifying the mains AC voltage supplied to the input (10); a DC-to-AC converter (5) that converts the rectified AC voltage into a converter AC voltage with a converter frequency; an output transformer (6, T1) with at least two outputs that galvanically isolates the primary-side converter AC voltage of the DC-to-AC converter (5) and converts it into a secondary-side output voltage with the converter frequency; and an output (11) connected downstream of the output transformer (6, T1) on the secondary side of the power supply device (1) for supplying at least one load (20), wherein the converter frequency is higher than the input frequency.