Common Faults and Causes of 10kV High-Voltage Outdoor Disconnect Switches During power system operation, problems with high-voltage outdoor disconnect switches are quite prominent and easily lead to equipment failures. Research has found that common faults currently manifest in the following types: 1. High-voltage insulator breakage; 2. Operating mechanism jamming; 3. Damage to conductive parts, etc.
(I) High-Voltage Insulator Breakage High-voltage outdoor disconnect switch faults causing high-voltage insulator breakage are mainly due to the long-term influence of climatic conditions. Because production methods are relatively backward, the standardized development of switch installation cannot be guaranteed. Although this type of fault currently accounts for a small percentage, its causes are often multifaceted, even accumulating over a long period under various factors. Therefore, this type of fault has the most profound impact during power system operation. Because high-voltage outdoor disconnect switches operate outdoors for extended periods, they are directly affected by weather conditions. In addition, the large temperature differences in northern regions cause significant variations in the expansion coefficients of components within the disconnect switch. Prolonged exposure to this condition can lead to poor connection between the high-voltage insulator and the metal base, even resulting in a serious risk of breakage. Furthermore, the installation and adjustment methods for high-voltage straight cylinder breakage and disconnect switches exhibit significant irregularities, and the maintenance methods used by personnel are also unreasonable. Because the switching and closing operations are subject to multiple impacts, the risk of breakage of the high-voltage straight cylinder body and base is greatly increased.
(II) Operating Mechanism Jamming Jamming of the high-voltage outdoor disconnect switch mechanism mainly occurs due to twisting and incomplete closing during operation. Because the connection position of the operating mechanism is affected, it is easy for the connection to break. If this problem occurs during normal operation, personnel need to promptly repair the fault and replace the equipment. During power emergency repairs, such problems can further expand the scope of the fault and even prolong the repair time, which is detrimental to the normal operation of the power system. Jamming of the disconnect switch operating mechanism is mainly due to significant problems in the installation and adjustment during mechanical transmission. During the initial installation of the disconnect switch, personnel failed to strictly follow the technical installation requirements, resulting in incomplete mechanism adjustment, which will significantly increase the mechanism deviation during operation.
(III) Damage to Conductive Parts The main cause of damage to the conductive parts of high-voltage outdoor disconnect switches is poor contact during operation. Due to insufficient switch actuation pressure, oxidation of the contact surface at the conductive parts occurs during prolonged periods of intermittent contact, ultimately leading to overheating and damage. Disconnect switches need to operate outdoors for extended periods, and the equipment is prone to aging during this time. Therefore, a reduction in the contact area can increase contact resistance, all of which increase the probability of conductive part damage.
Common Fault Prevention Solutions for High-Voltage Outdoor Disconnect Switches: Research on the aforementioned fault problems shows that for most faults, enhanced meticulous management and scientific maintenance can completely prevent them from occurring in advance. Therefore, in future work, relevant personnel can focus on the following aspects:
1. Starting from the source, strengthen quality control of disconnect switch manufacturers. Especially in the production of high-voltage straight cylinders and the connection of switch bases, it is necessary to ensure the rationality of production processes and operating procedures. Based on comprehensively improving monitoring effectiveness, improve the quality of disconnect switches leaving the factory and reduce the negative impact of this work on subsequent operation.
2. Disconnect switch manufacturers should strengthen the application of new methods and equipment, optimize and upgrade traditional insulation materials, improve the quality of high-voltage disconnect switches, effectively solve the problem of high-voltage straight cylinder breakage, actively carry out equipment maintenance and management, improve operational performance, effectively reduce and control the labor intensity at the work site, and avoid human factors interfering with the overall work.
3. It is recommended that the manufacturer optimize and adjust the structural design of the mechanical rotating parts, effectively implement sealing treatment, and comprehensively improve the performance of the bearing rotating parts. Effective measures should be taken to address and resolve the issue of bearing rust, preventing equipment deformation caused by damage to mechanical components and reducing the overall equipment failure rate.
4. During the maintenance and management of disconnect switches, personnel must always adhere to the principle of meticulous maintenance, conducting a thorough inspection of the entire disconnect switch equipment. Ensure that the connection between the high-voltage equipment cylinder and the switch base is effectively optimized, promptly repair damaged parts, strengthen anti-corrosion treatment of rusted areas, apply appropriate lubricating oil to the rotating shaft, smooth out burned areas, and promptly apply conductive paste. After effectively tightening the bolts, ensure the switch can operate effectively after maintenance, achieving a comprehensive improvement in maintenance safety.
5. Actively conduct daily inspections and management of high-voltage outdoor disconnect switches. Problems discovered during inspections directly impact subsequent work. Therefore, staff should enhance the use of specialized equipment such as far-infrared thermometers and high-magnification telescopes to promptly inspect the disconnect switches' appearance. Any abnormalities should be analyzed by temperature measurement, and the cause of the problem should be identified and addressed promptly to prevent equipment issues caused by disconnect switch defects. When conditions permit, staff should also optimize component properties during maintenance, promptly replacing equipment and materials with unstable performance. Only in this way can the operational failure rate of disconnect switches be reduced.
