A locking device for a substation disconnecting switch
Description: Patent No.:202210907058.9
Disconnectors at substation isolation faces serve as the sole isolation point between live and de-energized equipment. Misoperation of these disconnectors is a critical risk source for severe electrical accidents. Statistics show that over 80% of severe misoperations in the China Southern Power Grid since 2016 originated from failures in live-side disconnector control. Existing control methods have significant flaws: Method 1: Welding the disconnector drive shaft provides physical locking but requires firework approval processes and damages anti-corrosion coatings. Method 2: De-energization combined with manual supervision elevates control but fails to fully eliminate risks while increasing labor costs and operational complexity. Both methods suffer from low efficiency and insufficient reliability. Project Innovation This project developed a specialized non-destructive locking tool installed between the disconnector drive shaft and support structure. It achieves physical locking without welding or altering electrical circuits. Key innovations include: 1. Innovativeness & Practicality 1.1 Innovativeness Technical Design Innovations Modular Design: Comprising drive shaft locking components, positioning clamps, and limiters, the tool adapts to various disconnector types (circular, U-shaped, diamond drive plates), resolving compatibility issues. High-Strength Materials: Drive shaft clamps and locking collars use 45 steel (yield strength: 355 MPa, torque resistance: 50 N·m), exceeding typical disconnector drive torque (30 N·m). Positioning clamps employ 304 stainless steel for corrosion resistance and stability. Rapid Installation: Standardized lock screws (Grade 8.8) and limit screws (Grade 4.8) reduce installation time from 20 minutes to ≤5 minutes (75% efficiency gain). Technical Approach Innovations 3D Modeling & Prototyping: Simulation tests (tension, compression, torsion) optimized structural strength, replacing inefficient traditional blueprint methods. Anti-Corrosion Treatment: Surface coatings ensure zero rust after 20 days in 90% humidity environments. Industry Gap Filling Existing research focuses on software-based or administrative controls, lacking physical locking solutions for primary equipment. This tool introduces a "hard lock + rapid installation" approach, incorporated into Guangdong Power Grid’s Isolation Face Risk Control Guidelines and supported by 1 patent application. 1.2 Practicality Efficiency & Reliability: Tested at 220kV Zhaoqing Substation: 0% misoperation rate, ≤0.9° rotation under 30s force (safety threshold: ≤3°). Single-person installation in 4.7 minutes (target: ≤7 minutes), applicable to high/extra-high voltage scenarios. Broad Compatibility: Adjustable clamps and limiters fit drive shafts (20–80mm diameter), deployed across 46 substations (67 disconnectors) with 0% failure. Low Maintenance: Tool weight: 4.79kg (304 stainless steel); material costs reduced by 60% vs. welding. No approval processes required, minimizing operational complexity.
Organisation: Guangdong Power Grid Co., Ltd. Zhaoqing Power Supply Bureau
Innovator(s): He Junchi, Wu Rui, Wu Weiye, Huang Hansheng, Li Junhua、Wang Junjie, Wu Yanfang, Guangdong Power Grid Co., Ltd. Zhaoqing Power Supply Bureau
Category: Energy
Country: China