RU133362U1 - MULTI-SECTION DIAGRAM OF AUTOMATIC TURNING ON THE RESERVE OF POWER SUPPLY - Google Patents

Abstract

A multi-section scheme for automatically turning on the power supply reserve, containing at least three current converters (Tr No. 1, Tr No. 2, Tr No. 3, ...), each of which is connected to the inputs of the power sections through switching nodes (K1, K2, K3, ...) the number of which is determined from the condition Ns = Ntr-1, where Ns is the number of power sections, and Ntr is the number of current converters or other current sources (transformers, generators), and each switching node has at least one additional redundant connection with the input of another conversion current carrier.

Description

The utility model relates to electrical engineering and, in particular, to emergency control devices for transformer substations, diesel generator sets and can be used to prevent disturbances in normal power supply for any type of damage in the power supply network immediately after their occurrence and quick switching to backup power sources of all consumers connected to a three-phase voltage source.

A device for automatically turning on the backup power supply of consumers (“Power supply and electrical equipment of buildings and structures”, Textbook, Higher Education, Forum, SIC Infra-M, 2012 Ancharova TV, Stebunova ED, Rashevskaya MA) for automatic inclusion of backup power supply to consumers, containing primary and backup power sources. In particular, a circuit is known in which each terminal is connected to the corresponding power input via contactors (or circuit breakers with an electric motor drive). In case of power failure at one of the inputs, the sectional contactor is turned on, and the load section “A” is connected to the opposite input, the load section “B”. To protect the inputs, circuit breakers are provided in the circuit. The role of contactors can be performed by motor-protective circuit breakers. Figure 3

The known device for automatically turning on the backup power supply of consumers has the following disadvantages: low load utilization of each transformer. In the applied circuits, the transformer is used at 50-60% of the maximum power, or a backup transformer that is not connected to the load.

The technical result from the use of the utility model is to increase the efficiency of the use of supply transformers (generators) and increase the technical and economic indicators, as well as the reliability of the equipment. The main advantage of the new scheme is to reduce the risk of overloading backup power sources (transformers or generators) in the ABP mode. Installation of ATS schemes of a new scheme is faster and allows emergency and repair work to be carried out as quickly as possible. All tires involved in the circuit may be the same in maximum power. If the structural supply of the transformer is not used and its operation cannot exceed the installed capacity in the circuit with 3 combined transformers, the permissible load is 67%, and with 4 combined transformers - by 75% of the maximum power, under ideal conditions, i.e. during transition in the ABP mode, the transformers are 100% loaded.

In the proposed system, there is no sectional switch, sections are switched through a switching unit, which can be used, for example, a switch, a contactor, a circuit breaker with or without a motor drive, semiconductor devices that perform the function of connection or switching.

The proposed multi-sectional scheme provides for the possibility of sharing the load (3-phase 400 volts) outgoing from one source into separate sections.

The stated technical problem is solved in that a multi-section scheme for automatically turning on the power supply reserve contains at least three current converters (Tr No. 1, Tr No. 2, Tr No. 3 ...), each of which through switching nodes (K1, K2, K3 ...) connected to the inputs of the power sections, the number of which is determined from the condition Ns = Ntr-1, where Ns is the number of power sections, and Ntr is the number of converters or other current sources (transformers or generators). Each power section is connected to switching nodes with up to additional backup communication with the input of another current source (transformer, generator). If there is no or a decrease in voltage in the network of the main current source, the section is connected to the backup current source.

A multi-sectional reserve switching circuit can be applied in the presence of 3 or more converters (transformers or generators) of 3-phase alternating current.

The proposed scheme provides for the possibility of sharing the load (3-phase 400 volt network) into separate sections extending from one transformer. If three transformers (generators) are used in the circuit, then the load power supply sections will have two for each transformer and six total number of sections in the power supply circuit. If four transformers (generators) are used in the circuit, then the load power supply sections will be three for each transformer and twelve sections in the circuit.

Figure 1 presents the electrical circuit with 3 current converters.

Figure 2 is an example application of a multi-section automatic transfer switch with 4 current converters.

Regardless of the number of transformers used in the circuit, only one can be disconnected. Shutting down the next transformer will result in a power outage.

An example implementation of the system.

The standard circuit of a transformer substation consists of two sections and two transformers, Fig.3. When switching to a multi-section automatic transfer switch circuit, it is enough to add one transformer of the same capacity and divide the consumers into two additional sections. T.E. bring the circuit in accordance with the circuit of Fig 1. In this case, the power of the transformer substation will increase by 2 times, increase by 100%. The tests carried out with oil transformers of the TMP type (sealed) took into account the loads allowed by the manufacturer for 10 days for the mode increased load in ABP mode The test transformers were allowed to load 120%. In ABP mode, two transformers are under load, and one is disconnected. The total capacity was 240% of the rated power of one transformer. After turning on the third transformer, the load circuit returned to normal. The permissible load in these transformers in the normal mode amounted to 80% of the maximum power of each, while maintaining the ATS mode.

The control circuit can be organized using logical modules (controllers), which allows you to fully automate the process of switching control and monitoring the state of the circuit. Conventional relay circuits may also be used. Another switching module can be added to the switching unit of the guaranteed power section, which makes it possible to automatically start the diesel generator and switch the power section to it. With this scheme for organizing the ABP, additional equipment for organizing work using a diesel generator is not required. An additional positive aspect of the application of such a scheme is the unification of the elements used. This gives undeniable advantages during installation, operation and repair work.

Claims (1)

A multi-section scheme for automatically turning on the power supply reserve, containing at least three current converters (Tr No. 1, Tr No. 2, Tr No. 3, ...), each of which is connected to the inputs of the power sections through switching nodes (K1, K2, K3, ...) the number of which is determined from the condition Ns = Ntr-1, where Ns is the number of power sections, and Ntr is the number of current converters or other current sources (transformers, generators), and each switching node has at least one additional redundant connection with the input of another conversion current carrier.

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