Compact Medium-Voltage Voltage Regulator with SF6 Insulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing medium-voltage power grid voltage regulators require large space due to the spaced arrangement of air-cooled transformers and separate electronic control devices, leading to inefficient use of space and increased cooling requirements.
Innovation Solution
A compact arrangement where the feed transformer, additional transformer, tap changer, and control device are housed in a single oil-transformer tank, with the control device isolated in a separate partitioned area, allowing for reduced spatial requirements and improved electrical efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If air-cooled transformers are spaced apart to avoid arcing, then electrical safety is improved, but space requirement increases
Solution Approach 1:
The patent introduces sulfur hexafluoride (SF6) gas as an intermediary medium between the high-voltage transformer components. This gas provides superior dielectric strength and arc quenching properties compared to air, allowing transformer parts to be positioned much closer together while maintaining electrical safety. The SF6 gas acts as a mediator that enables reduced spacing without compromising arc avoidance.
Solution Approach 2:
The patent changes the physical medium from air to SF6 gas, fundamentally altering the dielectric parameters of the environment. This parameter change enables the transformer components to operate at higher electric field intensities with reduced clearance distances, directly addressing the space requirement issue while maintaining electrical safety.
2Reliability
If electronic control devices are placed in a separate building part, then electrical isolation is improved, but device complexity increases
Solution Approach 1:
The patent merges the electronic control devices with the high-voltage transformer housing into a single integrated structure. The control devices are mounted inside the same housing as the transformer, eliminating the need for separate buildings or structures. This merging reduces structural complexity while maintaining operational functionality.
Solution Approach 2:
The patent uses SF6 gas as an intermediary medium that provides electrical isolation between the low-voltage control circuits and high-voltage transformer components. This allows both control devices and transformer parts to coexist in the same housing space while maintaining necessary electrical isolation, resolving the contradiction between integration and isolation.
3Temperature
If large ventilation openings are provided for cooling transformers, then cooling efficiency is improved, but structural complexity increases
Solution Approach 1:
The SF6 gas in the housing serves multiple functions simultaneously: it provides electrical insulation, enables arc quenching, and acts as a cooling medium. This multi-functionality eliminates the need for separate large ventilation openings dedicated solely to cooling, as the SF6 gas circulation system handles thermal management while the housing structure remains relatively simple.
Solution Approach 2:
The patent employs fluid dynamics principles by utilizing SF6 gas circulation for cooling. The gas flows through the housing and around transformer components, carrying away heat through convection. This pneumatic cooling system replaces the need for large mechanical ventilation openings, reducing structural complexity while maintaining effective cooling.
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 solution achieves a 40% reduction in base area and simplifies the electrical and ventilation infrastructure, reducing costs and complexity while maintaining reliable high-voltage isolation and accessibility.
Implementation Method 1
The coils, of which each transformer preferably contains a total of three coils for each of the three phases of the medium-voltage power grid, can be arranged at such a close distance from one another due to the insulating effect of the transformer oil
Implementation Method 2
the coils of the feeder transformer and additional transformer and, if necessary, other components of the transformers, preferably the so-called active components of the transformers, are accommodated
Data Source
Figure 1
Figure 2
AI summary
An arrangement (1) for regulating voltage changes in a medium-voltage power network comprising a feed-in transformer (2) having a primary coil (2a) electrically coupled to a phase of the medium-voltage power network and a secondary coil (2b) with at least two secondary-coil-side taps (5.1, 5.2, 5.3), an auxiliary transformer (4) having a secondary coil (4a) connected in series with the at least one phase (P1, 2, 3) and a primary coil (4b), the latter being alternately connected via a tap changer (6) to the at least two secondary-side taps (5.1, 5.2, 5.3) for coupling an additional voltage provided by the feed-in transformer (2) into the phase (P1, 2, 3).3) is connectable, a control device (8) for actuating the tap changer (6) and a receiving space (10) in which the feed-in transformer (2), the auxiliary transformer (4) and the tap changers (6) and the control device (8) are received, is characterized in that the primary and secondary coils (2a, 2b) of the feed-in transformer (2), the primary and secondary coils (4a, 4b) of the auxiliary transformer (4) and the tap changer (6) are received in a first space area (10a) of the receiving space (10) in an oil transformer tank (12), and that the control device (8) is arranged in a second space area (10b) of the receiving space (10) separated from the first space area (10a) by a partition (14).