Power equipment serves as the hub and channel in power transmission and distribution networks. As the service life of equipment increases, its performance indicators will inevitably gradually decline under the influence of various environmental factors and external forces. From the time the equipment is put into operation to its final scrapping, its operating status not only reflects the realization of its own value but also relates to the personal safety of maintenance personnel. Therefore, understanding and mastering the status of power equipment through effective means is extremely important.
There are many reasons why equipment gradually ages, including:
● Power equipment is subjected to electrical, thermal, and mechanical loads during operation, as well as the effects of the natural environment (temperature, air pressure, humidity, and pollution, etc.). Long-term operation will cause aging, fatigue, and wear, resulting in a gradual decline in performance and reliability.
● Under long-term exposure to high voltage and high temperature, the composition and structure of the equipment's insulating materials change, dielectric loss increases, insulation performance decreases, and ultimately leads to the destruction of insulation performance. Insulators working in the atmosphere are also affected by environmental pollution, which reduces surface insulation performance and causes surface discharge faults.
● Under long-term heat load, the conductive materials of the equipment will be oxidized and corroded, which will increase the resistance and contact resistance, or reduce the mechanical strength and gradually lose the original working performance.
● The mechanical structural components of the equipment are subjected to long-term loads or operation, causing corrosion and wear, resulting in malfunction, air or liquid leakage, or other structural damage.
Different situations require different detection methods to detect potential faults as soon as possible. So, how do you choose the right method? This article will provide a detailed analysis of this issue.
For the inspection of power equipment, it is crucial to accurately understand the concept and scope of testing, correctly recognize its importance, and gain a deep understanding of testing technologies to prevent power safety issues before they arise. The "health index" of a piece of equipment comprises both its electrical and mechanical characteristics; however, the inability to obtain the "health value" of the electrical characteristics of power equipment during energized operation has long plagued power users. The emergence of new condition monitoring technologies has solved this problem. It not only expands the concept of power equipment testing but also fills a gap in the field.
The data provided by these two testing technologies constitute a complete "health index" for power equipment. Power equipment testing under the new concept is an advanced testing management model and a new, more effective testing strategy. It is a preventative operation performed based on equipment condition, effectively overcoming the problems of over-maintenance or neglect caused by scheduled inspections. It transitions from "mandatory maintenance upon expiration" to "mandatory maintenance when necessary," improving equipment availability, safety, and reliability. It is one of the effective ways for enterprises to modernize management and improve their overall strength, and it is also an important component of building a first-class power supply enterprise, a concrete manifestation of management and technological innovation.
Conventional power outage detection technology and condition monitoring technology complement each other, providing comprehensive data support for the reliable operation of power equipment. The concept of power equipment detection is accurately summarized as follows: Power equipment detection consists of two parts: condition monitoring and power outage detection. Condition monitoring provides electrical characteristic data of power equipment under energized operating conditions, while power outage detection provides partial electrical and mechanical characteristic data of power equipment under power outage conditions. These two detection technologies are indispensable and complementary. Power equipment detection should scientifically and rationally select different maintenance methods based on the importance, controllability, and maintainability of different equipment, forming an optimized comprehensive maintenance method that integrates fault repair, periodic maintenance, condition-based maintenance, and improvement maintenance to improve equipment reliability and reduce power supply costs.
Preventive testing of power equipment refers to the periodic inspection or testing of equipment already in operation according to prescribed testing conditions (such as prescribed testing equipment, environmental conditions, testing methods, and testing voltage), testing items, and testing cycles. This is to identify potential hazards in operating power equipment and prevent accidents or damage. It is a crucial measure to determine whether power equipment can continue to operate safely. With the rapid development of the social economy and the leaps and bounds in science and technology, the scope, equipment, and technology for power equipment testing are also evolving. However, these issues cannot all be eliminated by human observation or the experience of staff; specialized power equipment testing is necessary to detect these potential power safety hazards and organize personnel to eliminate them promptly. In power operation, power safety is always a top priority for those in the power industry. Power equipment testing effectively plays a role in preventing and identifying potential hazards. Therefore, power equipment testing (i.e., preventive testing of power equipment) is of paramount importance.
Conventional power outage detection and status monitoring (live detection) complement each other in determining the status of power equipment, and can meet the needs of different power users. It will gradually gain popularity in the future power service market.
