Box-type substation monitoring and protecting device

Abstract

The utility model relates to a monitoring and protecting device for a box-type substation. The monitoring and protecting device is characterized by comprising a high-voltage switch cabinet and an oil immersed transformer, an instrument chamber, a door and a vacuum circuit breaker are arranged in the high-voltage switch cabinet; a microcomputer protection device is installed in the instrument chamber and is connected to the vacuum circuit breaker. An internal gas relay and an oil temperature sensor are installed in the oil immersed transformer, and the internal gas relay and the oil temperature sensor are respectively connected to a microcomputer protection device. The door is provided with a pressure alarm indicating lamp and a temperature alarm indicating lamp and is connected with a microcomputer protection device. According to the device, the internal gas relay and the oil temperature sensor are arranged in the transformer, so that the transformer has temperature and pressure alarm monitoring and control protection functions, deflagration accidents caused by too high pressure are avoided, and safe operation is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of high voltage equipment, and in particular relates to a monitoring and protection device for a prefabricated substation. Background Technology

[0002] A prefabricated substation is a combination of high-voltage switchgear, distribution transformers, and low-voltage distribution equipment. It is suitable for urban power grid construction and renovation, particularly for residential areas, public substations, and busy city centers. A prefabricated substation is a compact outdoor distribution device that integrates high- and low-voltage distribution equipment and distribution transformers according to a specific wiring method. Types of prefabricated substations include European-style, American-style, underground, compact, and alternative (miniaturized) prefabricated substations, primarily used for 10kV distribution. They are installed in a moisture-proof, heat-insulated, fully enclosed steel structure box, offering advantages such as strong environmental adaptability, convenient installation, and small footprint. However, in actual use, the transformer's load capacity is relatively small, and the power supply reliability is not very high. Problems such as excessive load current or partial discharge short circuits causing oil temperature rise in the transformer frequently occur. When the transformer overheats, the internal pressure increases, posing a significant safety concern for users. This is a problem that urgently needs to be solved. Summary of the Invention

[0003] The problem this invention aims to solve is that in existing high-voltage substation equipment, during operation, transformer oil temperature rises due to excessive load current or partial discharge short circuits, leading to increased internal pressure and potentially causing deflagration accidents, thus compromising safety and usability. This invention provides a prefabricated substation monitoring and protection device. By installing an internal gas relay and oil temperature sensor within the transformer, it enables the transformer to possess temperature and pressure alarm monitoring and control protection functions, preventing deflagration accidents caused by excessive pressure and ensuring safe operation.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a box-type substation monitoring and protection device, mainly comprising a high-voltage switchgear and an oil-immersed transformer;

[0005] The high-voltage switchgear is equipped with an instrument room and door, and a vacuum circuit breaker; a microcomputer protection device is installed in the instrument room, and the microcomputer protection device is connected to the vacuum circuit breaker.

[0006] An internal gas relay and an oil temperature sensor are installed inside the oil-immersed transformer. The internal gas relay and the oil temperature sensor are respectively connected to a microcomputer protection device.

[0007] Pressure alarm indicator and temperature alarm indicator are installed on the door, and the pressure alarm indicator and temperature alarm indicator are respectively connected to a microcomputer protection device.

[0008] Preferably, the microcomputer protection device includes a microcontroller, a CPU, and a circuit breaker.

[0009] The advantages and positive effects of this utility model are:

[0010] 1. This utility model relates to a prefabricated substation monitoring and protection device. It utilizes an oil-immersed transformer with an internal oil temperature sensor and an internal pressure / gas relay, both connected to a microprocessor-based protection device. When the oil temperature rises due to excessive load current or partial discharge short circuit, the oil temperature sensor inside the transformer provides feedback to the microprocessor-based protection device. When the internal pressure increases due to excessive temperature, the pressure gauge on the gas relay provides feedback to the microprocessor-based protection device. When the oil temperature and pressure values ​​reach set values, the microprocessor-based protection device issues alarm signals, and the temperature alarm indicator and pressure alarm indicator emit audible and visual alarm signals to alert the user. The wiring is simple, effectively monitoring the substation.

[0011] 2. This utility model's prefabricated substation monitoring and protection device utilizes an oil temperature sensor and an internal pressure gas relay installed inside the oil-immersed transformer, which are respectively connected to a microprocessor-based protection device and a vacuum circuit breaker, to protect the substation. When the oil temperature of the oil-immersed transformer rises due to excessive load current or partial discharge short circuit, the temperature feedback from the internal oil temperature sensor is sent to the microprocessor-based protection device. When the internal pressure of the oil-immersed transformer increases due to excessive temperature, the pressure gauge of the gas relay sends feedback to the microprocessor-based protection device. When the oil temperature and pressure values ​​reach their respective thresholds, the microprocessor-based protection device sends a trip signal to the vacuum circuit breaker, causing it to trip. This prevents the transformer fault from escalating and causing transformer damage, or prevents a deflagration accident due to excessive pressure, ensuring safety.

[0012] 3. The monitoring and protection device for the box-type substation of this utility model adopts an internal pressure gas relay protection device with a built-in pressure gauge, which can directly transmit the pressure value to the microcomputer protection device. The microcomputer protection device issues a command to light up the indicator light or the vacuum circuit breaker trip signal according to the monitored pressure value, so as to prevent the transformer from deflagration accident due to excessive pressure, ensure safe operation, and reduce losses. Attached Figure Description

[0013] Figure 1 This utility model discloses a schematic diagram of the circuit structure of a box-type substation monitoring and protection device.

[0014] 1-Oil-immersed transformer, 2-Internal gas relay, 3-Oil temperature sensor, 4-Door, 5-Vacuum circuit breaker, 6-Temperature alarm indicator, 7-Pressure alarm indicator, 8-Microcomputer protection device, 9-Instrument room, 10-High voltage switchgear. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments.

[0016] like Figure 1 As shown, a prefabricated substation monitoring and protection device comprises a high-voltage switchgear 10 and an oil-immersed transformer 1. An instrument compartment 9 is installed in the upper part of the high-voltage switchgear 10, with a door 4 on the door 4. Pressure alarm indicator lights 7 and temperature alarm indicator lights 6 are installed on the door 4. A microprocessor-based protection device 8 is installed inside the instrument compartment 9, consisting of a microcontroller, CPU, circuit breaker, etc. The pressure alarm indicator lights 7 and temperature alarm indicator lights 6 are connected to the microprocessor-based protection device 8. The lower part of the high-voltage switchgear 10 is a high-voltage compartment, which houses a vacuum circuit breaker 5. The microprocessor-based protection device 8 is connected to the vacuum circuit breaker 5. The instrument compartment 9 and the high-voltage compartment are separated by a partition. The outer shell of the cabinet and the partition are made of aluminum-zinc coated steel plate.

[0017] An internal gas relay 2 and an oil temperature sensor 3 are installed inside the oil-immersed transformer 1. The internal gas relay 2 and the oil temperature sensor 3 are respectively connected to the microcomputer protection device 8.

[0018] When a prefabricated substation monitoring and protection device is in operation, 10kV power is supplied to the high-voltage switchgear 10 through the incoming cable.

[0019] When the oil temperature of an oil-immersed transformer rises due to excessive load current or partial discharge short circuit, the temperature probe of the oil temperature sensor 3 inside the transformer feeds back to the microprocessor protection device 8 in the box-type high-voltage switchgear 10. The microprocessor protection device 8 displays the transformer oil temperature in real time. When the oil temperature reaches the microprocessor protection set temperature, the microprocessor issues an alarm signal, and the indicator light on the control instrument door 4 emits an audible and visual alarm signal. This indicates that the oil temperature monitoring circuit, consisting of the oil temperature sensor 3, the microprocessor protection device 8, and the pressure alarm indicator light 7, is working, alerting the user.

[0020] When the oil-immersed transformer 1 experiences excessively high temperature, causing an increase in internal pressure, the internal gas relay 2 sends a feedback signal to the microprocessor-based protection device 8 in the high-voltage outgoing cabinet of the transformer substation. The microprocessor-based protection device 8 displays the transformer pressure value in real time. When the pressure reaches the microprocessor-based protection setting value, the microprocessor issues an alarm signal, and the indicator light on the control instrument door 4 emits an audible and visual alarm signal. This indicates that the pressure monitoring circuit consisting of the internal gas relay 2, the microprocessor-based protection device 8, and the temperature alarm indicator light 6 is working, alerting the user.

[0021] When the oil temperature of an oil-immersed transformer rises due to excessive load current or partial discharge short circuit, the temperature probe of the internal oil temperature sensor 3 feeds back to the microprocessor-based protection device 8 in the box-type high-voltage switchgear 10. When the internal oil temperature reaches the temperature threshold set by the microprocessor-based protection, a trip signal is sent to the vacuum circuit breaker 5, causing it to trip. In other words, the oil temperature protection circuit consisting of the oil temperature sensor 3, the microprocessor-based protection device 8, and the vacuum circuit breaker 5 is working, preventing the transformer fault from escalating and causing transformer damage, thus reducing losses for the user.

[0022] When the oil-immersed transformer 1 experiences excessively high temperature, causing an increase in internal pressure, the gas relay feeds back to the microprocessor protection device 8 in the box-type high-voltage switchgear 10. When the internal pressure of the transformer reaches the threshold set by the microprocessor protection device, a trip signal is sent to the vacuum circuit breaker 5, causing it to trip. In other words, the internal gas relay 2, the microprocessor protection device 8, and the vacuum circuit breaker 5 form a pressure protection circuit that is in operation, preventing the transformer from experiencing a deflagration accident due to excessive pressure and ensuring safety.

[0023] The embodiments of this utility model have been described in detail above, but the content described is only a preferred embodiment of this utility model and should not be considered as limiting the scope of implementation of this utility model. All equivalent changes and improvements made within the scope of this utility model should still fall within the scope of this patent.

Claims

1. A prefabricated substation monitoring and protection device, characterized in that: The device includes a high-voltage switchgear and an oil-immersed transformer. The high-voltage switchgear is equipped with an instrument room and door, and a vacuum circuit breaker; a microcomputer protection device is installed in the instrument room, and the microcomputer protection device is connected to the vacuum circuit breaker. An internal gas relay and an oil temperature sensor are installed inside the oil-immersed transformer. The internal gas relay and the oil temperature sensor are respectively connected to a microcomputer protection device. Pressure alarm indicator and temperature alarm indicator are installed on the door, and the pressure alarm indicator and temperature alarm indicator are respectively connected to a microcomputer protection device.

2. The prefabricated substation monitoring and protection device according to claim 1, characterized in that: The microcomputer protection device includes a microcontroller, a CPU, and a circuit breaker.

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