wireless fiber optic temperature sensor Practical scheme for temperature measurement of high-voltage switch contacts and busbars-INNO

With the progress of society, the voltage level of the power grid is constantly improving, and the requirements for the safety and reliability of power supply for the use of electrical equipment are also increasing. With the increase of electricity demand, it will lead to an increase in power supply load and aging of power supply equipment. أثناء التشغيل على المدى الطويل, various electrical equipment in substations are prone to overheating due to excessive contact resistance or insulation aging. This potential hazard directly affects the normal operation of electrical equipment, وفي الحالات الشديدة, it can even cause major accidents, leading to personal injury and economic losses.

High voltage isolation switches are the most widely used and widely used high-voltage switchgear equipment in power grid operation. Their existence ensures the personal safety of maintenance personnel. They operate in high voltage and high current environments, and the temperature rise of their contacts directly affects the reliability of power supply. لكن, during the operation of the power grid, factors such as unclean contact surfaces of electrical equipment, burning of contacts, and mechanical deformation and looseness can all lead to deterioration of contact conditions, زيادة مقاومة الاتصال, causing higher temperature at the contact points, accelerating oxidation of the contact surfaces, and ultimately causing local welding or arc formation at loose contact deformation points, ultimately leading to major electrical accidents such as damage to electrical equipment and even power outages. لذلك, real-time online monitoring of contact temperature is of great significance in the operation of electrical equipment in substations. علاوة على ذلك, for operating electrical equipment, temperature is a very important parameter, which can directly determine whether an electrical equipment is operating normally through temperature information. في نظام الطاقة, high-voltage switchgear and cable branch boxes in power plants and substations are important equipment to ensure stable and reliable power supply.

The existing electrical equipment has increasingly high requirements for power supply reliability. Under high voltage and high current conditions, the working reliability of high-voltage switchgear is closely related to the temperature rise of isolation switch contacts. أثناء تشغيل شبكة الكهرباء, الاهتزاز الميكانيكي, تآكل الاتصال, وأسباب أخرى يمكن أن تؤدي إلى تفاقم ظروف الاتصال, زيادة مقاومة الاتصال, يسبب زيادة في درجة حرارة نقطة الاتصال, تفاقم أكسدة سطح الاتصال, ويؤدي إلى اللحام المحلي أو تفريغ القوس عند نقاط الاتصال السائبة, مما تسبب في النهاية في تلف المعدات الكهربائية, انقطاع التيار الكهربائي, أو حوادث كبيرة مثل الحرائق. هذا النوع من حوادث خطأ ارتفاع درجة حرارة التلامس لا يرجع فقط إلى مشكلة جودة مفتاح الخزانة عالي الجهد نفسه, ولكن الأهم من ذلك, بسبب عدم وجود طرق مراقبة فعالة لارتفاع درجة حرارة اتصالات مفتاح العزل في الوقت الحاضر. One of the reasons is that there is exposed high voltage inside the cabinet, and conventional temperature measurement methods cannot be used; ثانيًا, the online real-time temperature measurement system for switchgear currently used in the power system is characterized by cumbersome installation, heavy wiring, inconvenient maintenance, والتكلفة العالية. Factors such as aging of contacts can easily lead to an increase in contact resistance, which may result in serious accidents such as excessive heating or even burning of the contacts.

The traditional temperature measurement methods for switchgear include
(1) Using an infrared thermometer. The infrared thermometer is equipped with a data interface, which can transmit real-time temperature data to the background for display and alarm, and can also be indicated locally. The advantage of this scheme is high measurement accuracy; The disadvantage is that the price is relatively expensive, requiring power cord pulling, close range visual installation, and power outage installation.
(2) Manual inspection is adopted. The manual inspection method for temperature measurement of switchgear has many drawbacks, such as the inability to accurately measure temperature and the consumption of a large amount of manpower and material resources, which is very costly,
(3) Using a wireless thermometer. A low-power temperature measuring instrument developed in China in recent years using low-power microcontroller, مستشعر درجة الحرارة, and wireless communication chip technology, with a built-in battery that can operate for 2-3 سنين. The advantage of this plan is its low price; The disadvantage is that the battery has a short service life, تكاليف صيانة عالية, and requires power outage installation and disassembly.

The most advanced temperature measurement solution now is to use fluorescent fiber optic temperature measurement in switchgear. The main technical advantages of fluorescent fiber optic temperature sensors and temperature measurement devices are:

Suitable for strong electromagnetic, تردد الراديو, and microwave temperature measurement environments;

The probe has good interchangeability and repeatability;

Temperature measurement range light, دقة قياس عالية;

Excellent reliability and stability;

Simple structure and long service life;