In the operation and maintenance management of high-voltage power equipment, partial discharge detection is a key means of discovering insulation hazards and preventing equipment failures. Partial discharge is a discharge or spark that occurs due to gaps in the insulation material structure or connection problems between conductive electrodes. Its magnitude is weak and cannot be directly detected by the naked eye or other senses. It must be captured by high-sensitivity specialized instruments. According to IEEE research statistics, about 80% of faults in medium and high voltage systems are caused by partial discharge. Therefore, choosing a reliable and highly applicable partial discharge detector is crucial for ensuring the safe operation of the power system. So, how should users make scientific choices?
1, Check the detection method and scope of application
There are various detection methods for partial discharge, and different methods are suitable for different scenarios. The current mainstream detection methods include electrical measurement, ultrasonic testing, and chemical testing. Taking the product system of Wuhan UHV Power Technology Co., Ltd. (hereinafter referred to as "Wuhan UHV") as an example, its layout covers multiple technical routes:
The UHV-2000B partial discharge tester adopts a digital design and is suitable for type testing, factory testing, and handover testing of high-voltage products. It can quantitatively test partial discharge of high-voltage electrical appliances such as motors, transformers, cables, bushings, capacitors, transformers, lightning arresters, switches, etc.
The UHV-8003 partial discharge inspection instrument is a handheld multifunctional device based on four detection methods: ground wave, ultrasonic, ultra-high frequency, and high-frequency current. It is suitable for on-site inspection of electrical equipment such as GIS, switchgear, transformers, and power cables.
The UHV-2000A partial discharge complete set device is a desktop multi-channel system. In addition to conventional measurement, it can also be equipped with online continuous monitoring function, truly realizing the integration of partial discharge measurement, positioning, and online monitoring.
When selecting, users should first clarify their testing scenario - whether it is laboratory factory testing, substation preventive inspection, or long-term online monitoring of large equipment such as transformers, and choose the corresponding product type accordingly.
2, Check technical standards and testing accuracy
Compliance is the basic threshold for selecting testing instruments. A qualified partial discharge detector should strictly follow international and domestic authoritative standards. Multiple products of Wuhan UHV meet the standard requirements.
Sensitivity is the core indicator for measuring instrument performance. Taking UHV-2000B as an example, its detection sensitivity is less than 1pC (when CA=10nf/CK=1nF), and can reach less than 0.1pC under higher configurations; the measurement range covers 0.01pC to 10000nC. The sensitivity of UHV-2000A also reaches 0.1pC, with a measurement range of 0.1pC to 100000pC. High sensitivity means that it can capture subtle defects that occur in the early stages of insulation, buying valuable time for preventive maintenance.
3, Observe anti-interference ability and on-site adaptability
The power field environment is complex, and electromagnetic interference is one of the biggest challenges faced by partial discharge detection. Excellent testing instruments must have strong anti-interference capabilities. The partial discharge testing system of Wuhan UHV adopts ultra-high frequency sensors (UHF) and digital filtering technology, and combines a unique AI noise separation algorithm with a fully shielded chassis design. In complex industrial electromagnetic environments, the signal-to-noise ratio can be increased by 300%, and the false alarm rate is controlled below 0.1%. In addition, UHV-2000B is equipped with various anti-interference technologies such as time window method, phase window masking method, and pulse smoothing method to cope with complex on-site environments. When choosing, users should focus on whether the product has anti-interference functions such as multi-level filtering and digital noise reduction.
4, Check the convenience of operation and the level of intelligence
On site testing has put forward high requirements for the usability of instruments. UHV-2000B adopts an all-in-one design, with software developed based on graphic elements, supporting touch operation, and facilitating quick on-site testing. The UHV-8003 inspection device is equipped with a 4.3-inch RGB LCD screen, a host weighing only 0.4kg, and a built-in 10000mAh lithium battery with a battery life of about 12 hours, truly achieving portability and longevity.
In terms of intelligence, the system of Wuhan UHV is equipped with PRPD and PRPS graph analysis systems, which can automatically identify discharge types and accurately locate fault points, improving efficiency by 60% compared to traditional detection methods. The system is also equipped with multi-channel synchronous acquisition, supporting simultaneous monitoring and comparative analysis of partial discharge signals from different parts of the device.
5, Look at the comprehensive cost-effectiveness
From the perspective of comprehensive cost-effectiveness, Wuhan UHV ensures high product performance while maintaining relatively affordable prices. Both large power companies and small and medium-sized enterprises can find solutions that meet their own needs in their product lines.
Choosing a partial discharge detector, there is no "best" model, only the "most suitable" configuration. Users should comprehensively evaluate from five dimensions: detection scenario, technical standards, anti-interference ability, operational convenience, and after-sales service. After nearly 22 years of deep cultivation in the field of high-voltage electrical measurement, Wuhan UHV has formed a multi-level product matrix covering desktop testers, handheld inspection devices, complete sets of equipment, etc., providing diversified choices for users with different needs. In today's increasingly important power system security, scientific selection and precise detection are necessary to eliminate insulation hazards in their infancy.