Analîz ya Tayanên Tecnîk yên Destpêkirina Rewşê Tirbijarkên Bîravderrastîn a Mezikî
Bijî her çêkirina serpilana sistemê ya elektrikê û derin bikina reformê ya sistemê ya elektrikê, şebexên rastî yên elektrikê diha ku bi tezî vegerandin da ku bibeşan wek şebexên malper. Mijarê pêwistina li ser rewşa cihazê ye ku hêj ji bo dargûnibûna demhatî rengên nû yên sensoran, destûrên taybetî yên komunikasyonê bi teknolojiya rêzanî yên modern û şopandina weraz û efektî bi sisteman mîninên paşger.
I. Analîza Strategiyê ya Pêwistan Li Ser Rewş
Pêwistan Li Ser Rewş (CBM) jî tiştên pêwistanê ye ku li ser agahdarî yên rewşê cihazan ku hatine verastkirin ji ala teknolojî yên parzûnên monitorî û tanîndaran, divê cihazan anêm û xerabekirin bibin bigihînin. Ya ku, pla'yan pêwistan bi rêya rewşê cihazan digire. Bi qeytebûna pêwistanê ya demhatî, strategiya CBM dikare kewaşên veşartin bigere û çareserkirin bike, di navbera ku pêwistan bi vêne demhatî tuşên insan û materialên berdest bikin. Şertên pelendikeş a CBM ye ku cihazan bi amûran monitoran online taybet be, ku dikarin parametreyên operasyonan bi demhatî şopandin û pêşdestkirina destûrê ji bo pêwistan li ser rewş. Monitorî online ya rewşê cihanên switchgear ên navenda meheng a încelina termal, xasên mekanîkî yên circuit breaker, endamên keyî sêdeme yên vacuum interrupters û performansa keyî componentan sêdeme.
II. Analîza Nîn Dergirî Teknolojîya Monitorî Termal Online
Di demê a operasyonê de cihanên switchgear ên navenda meheng, diravdanên rezîstans ên navenda lêkolîna contactên mobile û static, jointan main busbar û cable electric, û navcheyan din dikarin bigihînin ji ber ku nebeş li ser kirina an ên navenda lêkolîna, ku yekem dikare zêdetir bike termal ên navenda meheng. Eger ew kewaşan bet vêne gihînin, operasyonê pêşkeftîna switchgear dikare zêde bike heating û oxidation ên navenda lêkolîna, ku yekem dikare vîcîkêra xerab bike, ku dikare firotina konsekwencan wêneyan, wêne melting û falling off ên navenda lêkolîna, burning ên navenda lêkolîna, rapid degradation ên navenda insulation, û heta accidentan maligne yên breakdown û explosion.
Navenda meheng ên cihanên switchgear ên navenda meheng a voltage da. Eger measurement direct bikin, problemên high-voltage insulation û electrical isolation li ser high û low potentials dibe. Niha, metoda wan jî ye ku di bazarê de bikar anîn bi demhatî an indirect monitorî termal ên navenda meheng: sheets ên color-changing, temperature measurement infrared imaging, optical fiber temperature measurement, wired built-in temperature measurement, wireless embedded temperature measurement, etc.
Plana wan probleman ên measurement termal, lê rise ên termal da ye ku li ser magnitude ên current ên passing. Temperature measurement single bi measure current simultaneous nabe dikare accurate reflect real state ên engagement ên contacts mobile û static or lap joint ên busbar, leading to false alarms or missed alarms. Bija, device ên monitoring online ên rise ên termal dibêje cooperation bi system ên expert ên background for scientific analysis û diagnosis, which can judge whether the current rise ên termal abnormal according to the load current ên real-time û give processing suggestions accordingly.
III. Analîza Teknolojîya Monitorî Xasên Mehanîk û Electrical Life ên Circuit Breakers ên Vacuum
Circuit breakers ên vacuum jî important power equipment. According to statistics, more than half of the maintenance costs of substations are spent on high-voltage circuit breakers, and 60% of them are used for minor repairs and routine maintenance of circuit breakers. Frequent operations and excessive disassembly and maintenance will reduce the operation reliability of vacuum circuit breakers. Therefore, real-time on-line monitoring of vacuum circuit breakers helps to master their operation characteristics and change trends, shifting planned maintenance to condition-based maintenance.
Xasên mekanîk ên circuit breakers ên vacuum mainly include opening/closing time and speed, synchronism, contact pressure, overtravel, rebound amplitude, etc., which can be measured by linear displacement sensors, angular displacement sensors, pressure sensors and other devices. In the traditional method, the linear displacement sensor is installed at the bottom of the moving contact insulation pull rod of the vacuum circuit breaker, which requires a large space for linear movement, is not conducive to the miniaturization of equipment, and the sensor pull rod will have measurement errors due to wear or deformation. The new angular displacement sensor is installed at the mechanism spindle of the vacuum circuit breaker, which can accurately measure data such as overtravel, closing bounce time, opening rebound amplitude, closing speed, opening speed, closing time, opening time, etc., and the installation position is not easy to wear and convenient for maintenance. The contact pressure sensor is installed at the moving contact insulation pull rod, which can judge the state of the vacuum interrupter according to the change trend of the contact pressure value during opening and closing, and predict the remaining reliable electrical life of the vacuum interrupter by combining the analysis of historical switching load current conditions.
IV. On-line Monitoring Technology Analysis of Key Secondary Components of Vacuum Circuit Breakers
The on-line monitoring device for the state of secondary components of vacuum circuit breakers can realize the monitoring and data collection of the internal energy storage motor, opening coil, and closing coil of the circuit breaker. The most advanced current method is to use Hall elements to induce the magnetic field changes around the wires of execution equipment such as energy storage motors, opening coils, and closing coils, so as to achieve non-intrusive voltage and current measurement without worrying about the situation that the execution equipment cannot act due to the shutdown or damage of the monitoring device. Through real-time monitoring of the voltage and current of key secondary components of vacuum circuit breakers, operation and maintenance personnel can realize rapid diagnosis of potential faults of key secondary components through the analysis of fault waveforms and the comparison of front and back data. According to the diagnosis results, customers can formulate maintenance plans in advance to avoid serious impacts on power supply continuity after sudden faults.
V. Applications of Online Switch and Palmtop Switch
The online switch is a website system developed to provide remote condition monitoring, which can be accessed through any mainstream browser, including IE, Chrome, Firefox, Safari, etc. Based on a powerful cloud data center, the online switch filters, refines, and saves the large amount of status data obtained every day, then preliminarily filters various events according to threshold values and criterion algorithms, and issues alarms for suspected fault information. The online switch can set up perfect permission review and content grading designs to ensure the information security of user data.
The palmtop switch is a mobile terminal application developed specifically to provide remote condition monitoring. Based on Apple's advanced iOS system, it has powerful functions, high security, and is convenient for users to understand the operation status of medium-voltage switchgear anytime and anywhere, becoming a powerful assistant for maintenance workers.
Conclusion
With the development of intelligent monitoring technology and the popularization of the concept of condition-based maintenance, the on-line monitoring and on-line diagnosis schemes for medium-voltage switchgear are gradually improving and approaching maturity. After comprehensive application, they can effectively improve the comprehensive management and decision-making level of medium-voltage switchgear, realize standardized management and intelligent decision-making, and provide basic data support for the long-term safe and reliable operation and condition-based maintenance of medium-voltage switchgear. The continuous improvement of equipment management and decision-making levels will surely bring good economic and social benefits to the power industry. At present, however, the on-line monitoring devices for medium-voltage switchgear in China are of uneven quality, and it is necessary to conduct in-depth research on their principles, structures, and technical indicators, and select the optimal scheme to realize the on-line monitoring function of medium-voltage switchgear.
