The sensitivity of the first stage of protection, calculated with a metal two-phase short circuit on the busbars of the substation, must be at least 1.5. The sensitivity coefficient of the second stage of tire protection, determined with a metal two-phase short circuit behind the reactor, must be at least 1.2-1.3.
On fig. 12.11 shows a bus-coupling switch, the circuits of which, if present, must be connected to the busbar protection current circuits. At the same time, during the testing of the redundant busbar system through the buscoupling switch, a device must be provided in the protection circuit that automatically outputs the busbar protection action to all connections, with the exception of the buscoupling switch, in the same way as it was described above for full differential busbar protection. If the first stage of incomplete busbar differential protection does not provide the necessary sensitivity in case of busbar faults, partial busbar differential distance protection can be used. In this case, a distance protection circuit with one resistance relay is usually used with switching in the current and voltage circuits or only in the voltage circuits. The setting for the operation of the resistance relay is detuned from the short circuit behind the reactor. Starting current protection relays are used as the second stage in the same way as the scheme discussed above.
At large substations and power plants, in some cases, with the help of the second stage of incomplete differential busbar protection, it is not possible to provide the necessary sensitivity in case of short circuit over the reactor
Rice. 12.12. Structural diagram of the overcurrent protection of the transformer with acceleration in the absence of current in the outgoing lines
rum and outgoing lines. This is especially undesirable, since in the event of a fault downstream of the reactors up to the outgoing circuit breakers, the second stage of busbar protection is the only protection that is effective in case of a fault at this point. A number of methods have been proposed to ensure the shutdown of the short circuit after the reactors. All these methods are associated with the complication of the protection scheme and require the laying of an additional cable and the installation of additional equipment. So, for example, CTs installed on the most powerful lines are connected to the current circuits of incomplete differential busbar protection. Excluding part of the load current from the current passing in the relay during a short circuit after the reactor makes it possible to increase the sensitivity of the second stage of protection. At the same time, to disable the short circuit after the reactors of the lines, the CTs of which were connected to the differential protection circuits, special current protections are used, installed on these lines and operating with a time delay greater than that of their own maximum protection. It is also possible to use on the longest lines, the sensitivity in case of short circuit at the end of which is unsatisfactory, of special current protections, which also act to disconnect all connections of the section. Such protection can be performed both on each line, and in general for several lines.
In order to quickly turn off the short circuit on the 6-10 kV buses, the acceleration of the maximum current protection of the supply transformer is also used if there is no start-up of the protection of any of the connections extending from these tires. The block diagram of such accelerated protection is shown in fig. 12.12. Blocks 1-3 are the maximum current relay, time relay and transformer protection output circuits. Blocks 4X-4p correspond to current protection relays for 6-10 kV outgoing lines, which are connected to the transformer protection circuits through OR-NOT (DWU) and AND (DX) logic blocks.
In the event of a short circuit on the busbars of the substation, the current protection relays of transformer 1 will operate and none of the current protection relays of the outgoing lines 4±-4p will operate. In this case, at the output of the logical block there will be a signal that is one of the two allowing for the logical block DX. Since the second enabling signal will be received when current relay 1 is triggered, a signal is generated at the output of the logic block DX, which affects the output protection circuits, bypassing the time delay block 2. block DX, preventing the action of the transformer protection without a time delay.
RESERVATION OF FAULTS IN THE OPERATION OF RELAY PROTECTION AND BREAKERS
13.1. GENERAL INFORMATION
In ch. 6 and 7 the concept of the main and backup action of relay protection is given. As noted, the backup action is necessary to disable the short circuit in case of failure of the circuit breaker or relay protection of the damaged connection. An unswitchable short circuit has a destructive effect on the damaged element, it is dangerous for this electrical installation and for the electrical network as a whole. Therefore, redundancy of short circuit disconnection is a prerequisite for the implementation of relay protection. Reservation of short circuit disconnection using for this purpose the backup action of the protection of neighboring network elements is commonly called long-range redundancy. This redundancy method is highly reliable, since the redundant and redundant devices do not have common structural elements and therefore cannot be damaged for the same reason. Long-range redundancy does not require special relay protection devices. These positive traits long-range redundancy determine its wide distribution.
However, redundancy also has significant drawbacks: one of them is significant difficulties in providing the required sensitivity of protections that perform long-range redundancy, especially in complex networks with long and heavily loaded lines in the presence of parallel branches and powerful recharges. Along with distant redundancy, the so-called near redundancy is used. This method of redundant tripping is carried out by various means in case of failure of the relay protection or the circuit breaker. For redundancy, in addition to the main relay protection, this element of the electrical installation is equipped with a backup protection kit. The back-up protection operates to trip the same circuit breakers as the main protection. In this case, backup protection, as a rule, provides the necessary sensitivity in case of damage at the end of the protected line.
To improve the efficiency of short-range protection redundancy, it is necessary that the main and backup protections have independent measuring and operating circuits, as well as independent power sources. In addition, it is desirable that the main and backup protections have a different principle of operation, react to different electrical quantities, such as current and resistance, or other quantities. Such an implementation of the main and backup protections to the greatest extent eliminates the possibility of simultaneous failure of both protections due to one common cause.
Alexei Mikhailovich Remizov(June 24 (July 6), 1877, Moscow - November 26, 1957, Paris) - Russian writer. One of the brightest stylists in Russian literature.
Biography
Early years
Born into a Moscow merchant family. His second cousin Maria Vasilievna Remizova is the mother of the Russian botanist Konstantin Pangalo.
The writer's mother Maria Alexandrovna Naidenova was the sister of the famous industrialist and public figure N. A. Naidenov.
From childhood, Alexei Remizov was a great inventor and dreamer. At the age of 7, he wrote down a story about a fire in the village from the words of a nanny - this was his first realistic story. Later, work with "another's word" was transformed into a special author's style - creativity "according to the material." Then he decided to become a writer.
In 1895, Alexei Remizov graduated from the Moscow Alexander Commercial School and entered the Faculty of Physics and Mathematics of Moscow University. As a student, he was mistakenly arrested for resisting the police during a demonstration and exiled for 6 years to the north of Russia (Penza, Vologda, Ust-Sysolsk). Returning from exile in 1905 to St. Petersburg, Remizov began an active literary activity: his fairy tales and legends are published (“Lemonar, that is: Spiritual Meadow”, “Salting”, “Dokuk and joker”, “Nikolin's Parables”), novel (“Pond”) and stories (“Hours”, “Fifth Ulcer”) , dramatic works in the spirit of medieval mysteries (“The Tragedy of Judas, Prince Iscariot”, “Demonic Action”, “Tsar Maximilian”; in 1908, “Demonic Action” was presented at the Komissarzhevskaya Theater). The writer was ranked as a symbolist (and more widely - modernism), although Remizov himself did not position himself as a symbolist.
During the years of the revolution
During the years of the revolution and the subsequent years of war communism, Remizov remained in Petrograd, although he was politically anti-Bolshevik (he himself was close to the circles of the Socialist-Revolutionaries). In the summer of 1921, Remizov went to Germany for treatment - "temporarily", as the writer believed, but he was not destined to return.
In exile
In November 1923, Remizov moved, due to the economic crisis, from Berlin to Paris, where he spent the rest of his life. In exile, Remizov continued to write a lot (the most famous were his artistic memoirs about life in St. Petersburg and the revolution - “Whirled Russia” and “Cropped Eyes”), but it became more difficult to print every year. Remizov participated in the publication of the magazine Versta (Paris, 1926-1928), in which some of his works were published. Since 1931, the publication of Remizov's books has almost completely ceased. His friends and admirers founded a special small publishing house "Opleshnik" in 1953, which allowed the writer to publish new books.
At the end of his life he received Soviet citizenship. He was buried in the Sainte-Genevieve-des-Bois cemetery.
Wife (since 1903) - Serafima Pavlovna Remizova-Dovgello (1876-1943), paleographer.
Major works
- "Lemonar" (1907)
- "Salting" (1907)
- "Demonic Action" (1907)
- "Clock" (St. Petersburg, 1908)
- "Pond" (1908)
- "The Tragedy of Judas, Prince Iscariot" (1908)
- "Indefatigable tambourine" (1909)
- "Cross Sisters" (1910)
- "Action about George the Brave" (1910)
- "The Fifth Plague" (1912)
- "Collected works in 8 volumes" (1910-1912)
- "Word about the destruction of the Russian land" (1917)
- "Tsar Maximilian" (1919)
- "Tsar Dodon" (1921)
- "Russia in Letters" (1922)
- "Kukha" (1923)
- Whirled Russia (1926)
- "In Pink Glitter" (1952)
- "Tie" (1922)
- "The Power of Russia" (1911)
Creation
"A living treasury of the Russian soul and speech" called his work Marina Tsvetaeva. He is distinguished by an extremely vivid and imaginative perception of the world.
. One of the brightest stylists in Russian literature.
Alexei Remizov was born on July 6, 1877 in Moscow. The boy grew up in a wealthy merchant family. His mother belonged to the ancient Russian family of the Naydenovs, known for their observance of traditions and rituals. His uncle Nikolai Aleksandrovich Naydenov, his mother's brother, was the founder of a major Russian bank and chairman of the Moscow Stock Exchange Society. Its richest library was considered one of the best in the city, and Alexey Remizov read many books thanks to this. Also, the boy's mother was distinguished by advanced views, participated in the Bogorodsk circle of nihilists.
From childhood, Alexey was distinguished by a rich imagination and a craving for mischief. His childhood hobbies: drawing, music, theatre, stayed with him for the rest of his life. Severe myopia prevented him from receiving systemic musical education, but influenced the development of fantasy. The game beginning of life, which he took for himself as the main one, accompanied him all subsequent years.
Alexei received a good home education. He studied at a commercial school, after which he entered the Faculty of Physics and Mathematics of Moscow University. He was interested in the works of Herzen, Chernyshevsky, read Marxist literature.
After the first course, Remizov went on a trip abroad, which became fatal for him. He brings a suitcase of forbidden literature from abroad, this became the reason for close attention to him from the police. On the day of memory of the victims of Khodynka, Aleksey takes part in mass gatherings, for which he was detained by the police, then he was accused of organizing riots and exiled to Penza for two years. There he only aggravated his position by joining the circle of Vsevolod Meyerhold. This led to new charges and exile in the Vologda region for three years under police supervision.
In Vologda he happened to meet many Russian philosophers and public figures. Also there, several fateful events happened to him: he met his future wife, finally realized his creative destiny and forever rejected revolutionary activity for himself.
In the same place, in Vologda, Alexei Mikhailovich publishes his first texts in the newspaper "Kurier". He begins to write under the influence of Veselovsky's work on Russian verse. At the same time, the first edition of the novel "The Pond" appeared, in which he anticipated the traditions of existential literature.
Returning from exile in St. Petersburg in 1905, Remizov began an active literary career: his fairy tales and legends “Limonar, that is, Spiritual Meadow”, “Salting”, “Dokuk and Joker”, “Nikolin’s Parables”, the novel “Pond” are published and the story "The Hours", "The Fifth Plague", dramatic works in the spirit of medieval mysteries "The Tragedy of Judas, Prince Iscariot", "Demonic Action", "Tsar Maximilian". In 1908, the "Demonic Action" was presented at the Komissarzhevskaya Theater. The writer was ranked as a symbolist and, more broadly, modernism, although Remizov himself did not position himself as a symbolist.
In 1910, the story "The Cross Sisters" was published, which showed the mature Remizov, the successor best traditions Russian literature. In the Petersburg period, he writes a lot, improving his artistic style. The biography and books of the author become well known to a wide Russian readership. Remizov Aleksey in 1912 publishes an 8-volume collection of his works in the publishing house of Vyacheslav Ivanov. By 1917 he was already a popular, accomplished writer.
During the years of the revolution and the subsequent years of war communism, Remizov remained in St. Petersburg, although he was politically anti-Bolshevik. In the summer of 1921, he went to Germany for treatment, “temporarily,” as the writer believed, but he was not destined to return.
For two years he was in a state of uncertainty, filed a petition to return to the Soviet Union. However, in November 1923, the Remizov family moved to Paris. The reasons for this choice remain unknown. Here they will live until the end of their days. Remizov Alexei Mikhailovich continued to consider himself a part of Russia all his life. During World War II, he actively sympathized with the Soviet Union. The years of emigration became very productive for the writer. He writes a lot, continues to draw, in the 30s he even earns a living from drawings.
The works of Remizov, the artist, were admired by Marc Chagall, Wassily Kandinsky, Pablo Picasso. During the war years, he kept a “graphic diary”, which reflected dreams, portraits of contemporaries and events that worried him. At the end of his life he received Soviet citizenship.