RU2815919C1 - Method of protection against arc and partial discharges - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to methods of relay protection and automation of 6-10 kV switchgears and is intended for detection of faults leading to occurrence of electric arc inside switchgear cubicle and disconnection of circuits in which it occurred. Said technical result in the implementation of the invention is achieved by the fact that in the known method, which includes supplying an acoustic signal from a complete distribution device to a sensitive element and conversion of continuous signal in converter, feature consists in fact that wideband microphone is used as sensitive element, which is connected through an analogue-to-digital converter by means of a digital channel to a server, which includes a signal analyser, database, knowledge base, decision-making subsystem, which is connected to the database and the knowledge base with the possibility of exchanging with them information on the characteristics of signals coming from the signal analyser of the complete distribution device, as well as previously obtained characteristics of signals of other complete distribution devices, wherein the signal of the switchgear converted by the analogue-to-digital converter is supplied to the server, where it is processed by the signal analyser, supplied to the decision-making subsystem, decision-making subsystem exchanges information with the knowledge base and the database, compares the data of these bases, and at detection of pre-emergency and emergency state of complete distribution device disconnects it from power circuit.

EFFECT: increased efficiency of protection against partial and arc discharges of complete distribution devices.

1 cl, 1 dwg

Description

Field of technology to which the invention relates

The invention relates to methods of relay protection and automation of 6-10 kV switchgear and is intended for detecting faults leading to the occurrence of an electric arc inside the switchgear cabinet and disconnecting the circuits in which it occurred.

State of the art

The closest method of the same purpose to the claimed invention in terms of the set of characteristics is the method of arc protection, in which arc protection is carried out by fixing the light of an electric arc with a light guide and converting it through a photoelectronic converter into an electrical analogue, when the threshold level is exceeded, the switch turns off the power circuit switchgear cabinets (see Pat. RU No. 2379811 C1 dated January 20, 2010, Bulletin No. 2), adopted as a prototype.

The reasons preventing the achievement of the technical result indicated below when using the known method adopted as a prototype include the impossibility of registering partial discharges and the insufficient effectiveness of protection against arc discharges.

Disclosure of the invention

The technical result is an increase in the efficiency of equipment protection from partial and arc discharges of complete switchgears.

The specified technical result when implementing the invention is achieved by the fact that in the known method, which includes supplying an acoustic signal from a complete distribution device to a sensitive element and converting a continuous signal in a converter, the peculiarity lies in the fact that a broadband microphone is used as a sensitive element, which is connected via an analogue - a digital converter via a digital channel to a server that includes a signal analyzer, a database, a knowledge base, a decision-making subsystem, which is connected to the database and knowledge base with the ability to exchange information with them about the characteristics of the signals coming from the signal analyzer of the complete switchgear , as well as previously obtained characteristics of signals from other complete switchgears, while the signal of the complete switchgear, converted by an analog-to-digital converter, is fed to the server, where it is processed by a signal analyzer, fed to the decision-making subsystem, the decision-making subsystem exchanges information with the knowledge base and the database data, compares the data from these databases, and when a pre-emergency and emergency condition of the complete switchgear is detected, disconnects it from the power circuit.

Brief description of drawings

Figure 1 shows a schematic diagram explaining the method of protection against arc and partial discharges, where: 1 – protection device, 2 – sensitive element (acoustic sensor), 3 – complete switchgear, 4 – converter (analog-to-digital), 5 – protection device input, 6 – protection device output, 7 – digital channel, 8 – server, 9 – signal analyzer, 10 – knowledge base, 11 – database, 12 – decision-making subsystem, 13 – switch, 14 – power circuit.

Carrying out the invention

The method of protection against arc and partial discharges is implemented as follows. The acoustic signal from the operation of the complete distribution device 3 is supplied through the input of the protection device 5 to the sensitive element 2, which is a broadband microphone operating in the frequency range from 100 Hz. To convert the continuous signal from the sensitive element 2 into a digital code, converter 4 (analog-to-digital) is used. The resulting digital code is transmitted via digital channel 7 to server 8. The digital code arriving at server 8 is processed by signal analyzer 9, in which unwanted signal components are removed. The processed signal from the signal analyzer 9 enters the decision-making subsystem 12, to which the knowledge base 10 and database 11 are connected. The knowledge base 10 is used to store information about the previously obtained signal characteristics of the operation of complete switchgears in normal, pre-emergency and emergency states. The database 11 is used to store information about the characteristics of the signals received from the complete switchgear 3. The decision-making subsystem 12 exchanges information about the digital code received from the signal analyzer 9 with the knowledge base 10 and the database 11 and, based on a comparison of information, one of the states is identified complete switchgear 3: normal, pre-emergency and emergency. In the event of a pre-emergency condition (a prerequisite for the occurrence of partial and arc discharges) or an emergency, the decision-making subsystem 12 sends a signal through the output of the protection device 6 to the switch 13 about the unstable operation of the complete switchgear 3. Reacting to the received signal, the switch 13 turns off the complete switchgear 3 from the power circuit 14.

The use of the proposed technical solution allows for continuous monitoring of the operation of the complete switchgear and its disconnection from the power circuit when arc and partial discharges occur.

Compared to the prototype, which implements an optical method for detecting an emergency situation in a complete switchgear in the presence of an arc, the proposed method of protection through the use of a broadband microphone implements an acoustic method for detecting an emergency situation before the occurrence of an arc, which helps prevent damage to equipment.

Increasing the efficiency of protecting equipment from partial and arc discharges is confirmed by the fact that the acoustic method of detecting an emergency situation of a complete switchgear makes it possible to detect the occurrence of partial discharges before the appearance of an arc and protect the equipment from damage from both partial and arc discharges, and the known method of protection - the prototype detects an emergency situation only in the presence of an arc and does not protect against partial discharges.

Claims (1)

A method of protection against arc and partial discharges, including supplying an acoustic signal from a complete switchgear to a sensitive element and converting a continuous signal in a converter, characterized in that a broadband microphone is used as a sensitive element, which is connected through an analog-to-digital converter via a digital channel to the server , which includes a signal analyzer, a database, a knowledge base, a decision-making subsystem, which is connected to the database and knowledge base with the ability to exchange information with them about the characteristics of signals coming from the signal analyzer of a complete switchgear, as well as previously obtained characteristics of signals from other complete distribution devices, while the signal of the complete distribution device converted by an analog-to-digital converter is fed to the server, where it is processed by a signal analyzer, fed to the decision-making subsystem, the decision-making subsystem exchanges information with the knowledge base and the database, compares the data of these databases, and when When detecting a pre-emergency and emergency condition of a complete switchgear, it disconnects it from the power circuit.