On-Load Tap Changer Positioning for Contact-Safe Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing on-load tap changers face risks of mechanical damage to contacts during assembly and disassembly due to unwanted mechanical interactions.
Innovation Solution
The on-load tap changer incorporates a rotational positioning device and an axial blocking device to adjust the relative rotational and axial positions of the dynamic and static units, ensuring the movable contacts are disengaged or engaged with the fixed contacts during assembly and disassembly, respectively, thereby preventing mechanical damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the dynamic unit is lowered into the static unit during assembly, then assembly is enabled, but mechanical damage to contacts may occur due to unwanted mechanical interactions
Solution Approach 1:
The rotational positioning device is activated before the dynamic unit is fully lowered into the static unit. This preliminary rotation ensures that the movable contacts are positioned away from the fixed contacts during the assembly process, preventing unwanted mechanical interactions and potential damage while still enabling the assembly to proceed
Solution Approach 2:
The rotational positioning device acts as an intermediary mechanism between the assembly process and the contact engagement. By controlling the rotational position of the dynamic unit relative to the static unit, it mediates the interaction between movable and fixed contacts, ensuring they only engage when properly positioned and preventing damage during the assembly operation
2Reliability
If the movable contacts are engaged with fixed contacts during operation, then electrical connection is established, but mechanical damage risk increases during disassembly
Solution Approach 1:
Before the disassembly process begins by lifting the dynamic unit out of the static unit, the rotational positioning device is activated to rotate the dynamic unit to a safe position. This preliminary action disengages the movable contacts from the fixed contacts, eliminating the risk of mechanical damage during disassembly while maintaining reliable electrical connection during operation
Solution Approach 2:
The system dynamically adjusts the rotational position of the dynamic unit based on the operational state. During operation, the contacts are engaged for reliable electrical connection. During disassembly, the system dynamically rotates the dynamic unit to disengage the contacts, preventing mechanical damage. This dynamic adaptation resolves the contradiction between maintaining reliable connection and preventing damage
Data Source
Figure 1
Figure 2A~2D
Figure 3A~3B
AI summary
An on-load tap changer (1) comprises a static unit (2) comprising fixed contacts (4a-4e, 5a-5e) for connection to taps at a transformer winding, a dynamic unit (7) comprising at least one movable contact (8, 9) for selectively contacting one of the fixed contacts (4a-4e, 5a-5e) during operation of the transformer, and comprises a rotational positioning device (14) for adjusting the rotational position of the dynamic unit (7) relative to the static unit (2) during at least one of assembly or disassembly of the tap changer (1).