Digital Correction of Readings Produced by Fluid Level Measurement Channels at NPPs Equipped with Sensors Having a Dead Zone
DOI:
https://doi.org/10.24160/1993-6982-2021-2-119-125Keywords:
liquid media hydrostatic level measurements, sensor dead zone, nuclear power plantAbstract
The introduction and development of computerized digital systems in modern power engineering has led in Russia to a full modernization of domestically produced nuclear power plant measurement systems. In particular, digital methods for correcting the readings of hydrostatic level sensors have been widely put in use since 2013. The experience gained from putting them in use was generalized in the reference and organizational and methodological literature in 2017. However, the subsequent results of preoperational adjustments carried out at newly designed nuclear power units and at those under construction have shown that some issues still remain unresolved in this application field. In particular, there is a need is to develop digital methods for correcting the readings produced by channels measuring the level of liquid media in pressurized process tanks if there occurs a sensor dead zone.
The complexity of this problem is stemming from the fact that it is not possible to take the sensor dead zone into account by introducing a constant correction to the measurement channel readings in view of the technological process peculiarities. Thus, during the operation of nuclear power units, the water density in pressurized process tanks and vessels decreases from 980 to 590 kg/m3, and the vapor density increases from 0 to 100 kg/m3. Such changes give rise to complex thermal and physical interphase processes that occur under the conditions of large mass transfers of the vapor--water mixture. As a result, the sensor's dead zone boundary undergoes an essential change in the tank longitudinal section depending on the current values of the working fluid thermal and physical characteristics.
To solve this problem, digital methods for online correction of measured level readings are proposed that take into account changes in the two-phase working medium (vapor--water) in the course of a continuous technological process.
Nowadays, the introduction of digital methods for correcting the hydrostatic level sensor readings is especially relevant in connection with the development of industry programs aimed at increasing the capacity of newly designed and operating nuclear power units, which pose more demanding requirements to the accuracy of thermal and physical measurements and operational safety as a whole.
References
2. Калашников А.А. Корректировка показаний измерительных каналов уровня с датчиками разности давлений на АЭС // Контроль. Диагностика. 2015. № 12. С. 69—75.
3. Калашников А.А. Справочник по настройке промышленных гидростатических уровнемеров. М.: Инфра-инженерия, 2017.
4. Иванова Г.М., Кузнецов Н.Д., Чистяков В.С. Теплотехнические измерения и приборы. М.: Издат. дом МЭИ, 2007.
5. СП 77.13330.2016. Системы автоматизации. Актуализированная редакция СНиП 3.05.07—85.
6. Александров А.А., Григорьев Б.А. Таблицы теплофизических свойств воды и водяного пара. М.: Изд-во МЭИ, 1999.
7. Тверской Ю.С., Таламанов С.А. Технология АСУ ТП электростанций (особенности, проблемы и перспективы развития // Вестник Ивановского гос. энергетического ун-та. 2010. № 3. С. 117—123.
8. ГОСТ 22520—85. Датчики давления, разрежения и разности давлений с электрическими аналоговыми выходными сигналами ГСП. Общие технические условия.
9. Александров А.А. Система уравнений IAPWS-IF-97 для вычисления термодинамических свойств воды и водяного пара в промышленных расчетах. Ч. 1. Основные уравнения // Теплоэнергетика. 1998. № 9. С. 69—77.
10. Александров А.А. Система уравнений IAPWS-IF-97 для вычисления термодинамических свойств воды и водяного пара в промышленных расчетах. Ч. 2. Дополнительные уравнения // Теплоэнергетика. 1998. № 10. С. 64—71.
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Для цитирования: Воронков И.А., Калашников А.А. Цифровая коррекция показаний измерительных каналов уровня жидких сред с областью нечувствительности датчиков на атомных электрических станциях // Вестник МЭИ. 2021. № 2. С. 119—125. DOI: 10.24160/1993-6982-2021-2-119-125.
#
1. PM.ATE.813.0191—2013. Metody Korrektirovki Pokazaniy Izmeritel'nykh Kanalov Davleniya, Urovnya i Raskhoda na AES s Reaktorom Tipa VVER. (in Russian).
2. Kalashnikov A.A. Korrektirovka Pokazaniy Izmeritel'nykh Kanalov Urovnya s Datchikami Raznosti Davleniy na AES. Kontrol'. Diagnostika. 2015;12:69—75. (in Russian).
3. Kalashnikov A.A. Spravochnik po Nastroyke Promyshlennykh Gidrostaticheskikh Urovnemerov. M.: Infra-inzheneriya, 2017. (in Russian).
4. Ivanova G.M., Kuznetsov N.D., Chistyakov V.S. Teplotekhnicheskie Izmereniya i Pribory. M.: Izdat. Dom MEI, 2007. (in Russian).
5. SP 77.13330.2016. Sistemy Avtomatizatsii. Aktualizirovannaya Redaktsiya SNiP 3.05.07—85. (in Russian).
6. Aleksandrov A.A., Grigor'ev B.A. Tablitsy Teplofizicheskikh Svoystv Vody i Vodyanogo Para. M.: Izd-vo MEI, 1999. (in Russian).
7. Tverskoy Yu.S., Talamanov S.A. Tekhnologiya ASU TP Elektrostantsiy (Osobennosti, Problemy i Perspektivy Razvitiya. Vestnik Ivanovskogo Gos. Energeticheskogo Un-ta. 2010;3:117—123. (in Russian).
8. GOST 22520—85. Datchiki Davleniya, Razrezheniya i Raznosti Davleniy s Elektricheskimi Analogovymi Vykhodnymi Signalami GSP. Obshchie Tekhnicheskie Usloviya. (in Russian).
9. Aleksandrov A.A. Sistema Uravneniy IAPWS-IF-97 dlya Vychisleniya Termodinamicheskikh Svoystv Vody i Vodyanogo Para v Promyshlennykh Raschetakh. Ch. 1. Osnovnye Uravneniya. Teploenergetika. 1998;9:69—77. (in Russian).
10. Aleksandrov A.A. Sistema Uravneniy IAPWS-IF-97 dlya Vychisleniya Termodinamicheskikh Svoystv Vody i Vodyanogo Para v Promyshlennykh Raschetakh. Ch. 2. Dopolnitel'nye Uravneniya. Teploenergetika. 1998;10:64—71. (in Russian).
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For citation: Voronkov I.A., Kalashnikov A.A. Digital Correction of Readings Produced by Fluid Level Measurement Channels at NPPs Equipped with Sensors Having a Dead Zone. Bulletin of MPEI. 2021;2:119—125. (in Russian). DOI: 10.24160/1993-6982-2021-2-119-125.
