Alarm device for reflecting contact condition of carbon brush of generator rotor

Abstract

The utility model relates to an alarm device for reflecting the contact condition of a generator rotor carbon brush. The alarm device comprises a generator rotor carbon brush and rotor large shaft secondary loop and an alarm loop, when the contact condition of the generator rotor carbon brush is good, the current type relay in the secondary circuit is excited, the generator rotor carbon brush and the rotor large shaft secondary circuit work normally, and the alarm circuit is disconnected. When the abrasion degree of the generator rotor carbon brush is large, the generator rotor carbon brush is out of contact with the generator rotor, the current type relay in the secondary circuit is not excited, the current type relay contact is connected with the alarm circuit, and the local control unit in the alarm circuit sends out an alarm signal.

Description

Technical Field

[0001] This utility model belongs to the field of hydroelectric generator protection, specifically relating to an alarm device that reflects the contact status of the generator rotor carbon brushes. Background Technology

[0002] In large hydroelectric power plants, measuring the generator rotor shaft current and configuring generator rotor single-point grounding protection both require the use of generator rotor carbon brushes to connect the circuit to the generator rotor shaft. Because the generator rotor shaft rotates at high speed continuously during operation, the carbon brushes continuously wear down. If the carbon brushes wear down significantly and lose contact with the rotor shaft, the rotor single-point grounding protection will fail. In typical hydroelectric power plants, generator rotor carbon brushes are mainly inspected manually, with the length of the brushes visually determined to determine if replacement is necessary. However, the areas where generator rotor carbon brushes are installed are generally small and poorly lit, making visual inspection unreliable and requiring on-site checks each time, which is very inconvenient. Therefore, how to add an alarm mechanism for when the carbon brush loses contact with the rotor shaft is the problem this invention aims to solve. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to provide an alarm device that reflects the contact status of the generator rotor carbon brushes, and can issue an alarm signal when the generator rotor carbon brushes lose contact with the shaft.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: an alarm device reflecting the contact status of generator rotor carbon brushes, which includes a secondary circuit between the generator rotor carbon brushes and the rotor shaft and an alarm circuit; the secondary circuit between the generator rotor carbon brushes and the rotor shaft and the alarm circuit are electrically connected through a current-type relay. When the current-type relay is energized, the secondary circuit between the generator rotor carbon brushes and the rotor shaft is connected; when it is not energized, the alarm circuit is connected.

[0005] The secondary circuit of the generator rotor carbon brush and rotor shaft includes a power supply, a control switch, a resistor, a current-type relay, the generator rotor carbon brush, and the generator rotor shaft. One end of the generator rotor carbon brush is in contact with the generator rotor shaft, the other end of the generator rotor carbon brush is electrically connected to one end of the current-type relay, the other end of the current-type relay is electrically connected to one end of the resistor, the other end of the resistor is electrically connected to the positive terminal of the power supply, and the negative terminal of the power supply is electrically connected to the control switch.

[0006] The alarm circuit includes a second contact of a current-type relay and a local control unit; the second contact of the current-type relay is electrically connected to the local control unit to form a circuit.

[0007] The other end of the generator rotor shaft and the other end of the control switch are grounded.

[0008] There is a grounding resistance between the two grounding points of the generator rotor shaft and the control switch.

[0009] The control switch controls the connection and disconnection of the generator rotor carbon brushes and the secondary circuit of the rotor shaft.

[0010] When the generator rotor carbon brush loses contact with the generator rotor, the current-type relay in the secondary circuit of the generator rotor carbon brush and the rotor shaft is not energized, the second contact of the current-type relay connects the alarm circuit, and the local control unit in the alarm circuit issues an alarm signal.

[0011] The main beneficial effects of this utility model are as follows:

[0012] The secondary circuit alarm mechanism eliminates the need for on-site inspection of the rotor shaft carbon brushes by staff and provides a reliable alarm when the rotor shaft carbon brushes lose contact with the shaft.

[0013] The alarm device can be controlled to be connected or not by a control switch. Disconnection means that the alarm circuit is not used, and connection means that the alarm circuit is used.

[0014] The grounding resistance between the other end of the generator rotor shaft and the other end of the control switch, and the grounding resistance between the two grounding points, can ensure safety during the operation of electrical equipment. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] Figure 1 This is a secondary circuit diagram of the generator rotor carbon brush and rotor shaft of this utility model.

[0017] Figure 2 This is the alarm circuit diagram of this utility model.

[0018] In the diagram: 11 current-type relay; 12 power supply; 13 control switch; 14 resistor; 15 generator rotor carbon brush; 16 generator rotor shaft; 17 grounding resistor; 21 second contact of current-type relay; 22 local control unit. Detailed Implementation

[0019] like Figures 1-2An alarm device reflecting the contact status of generator rotor carbon brushes is characterized by comprising a secondary circuit between the generator rotor carbon brushes and the rotor shaft, and an alarm circuit. The secondary circuit between the generator rotor carbon brushes and the rotor shaft, and the alarm circuit are electrically connected via a current-type relay 11. When the current-type relay 11 is energized, the secondary circuit between the generator rotor carbon brushes and the rotor shaft is connected; when it is not energized, the alarm circuit is connected. This enables the second contact 21 of the current-type relay to automatically connect to the alarm circuit when the generator rotor carbon brushes 15 have poor contact, causing the local control unit 22 in the alarm circuit to issue an alarm signal.

[0020] In a preferred embodiment, the secondary circuit of the generator rotor carbon brush and rotor shaft includes a power supply 12, a control switch 13, a resistor 14, a current-type relay 11, a generator rotor carbon brush 15, and a generator rotor shaft 16. One end of the generator rotor carbon brush 15 is in contact with the generator rotor shaft 16, and the other end of the generator rotor carbon brush 15 is electrically connected to one end of the current-type relay 11. The other end of the current-type relay 11 is electrically connected to one end of the resistor 14, and the other end of the resistor 14 is electrically connected to the positive terminal of the power supply 12. The negative terminal of the power supply 12 is electrically connected to the control switch 13. The resistor 14 is used to prevent the current-type relay 11 from being damaged due to excessive voltage across it.

[0021] In a preferred embodiment, the alarm circuit includes a second contact 21 of a current-type relay and a local control unit 22; the second contact 21 of the current-type relay and the local control unit 22 are electrically connected to form a circuit, and when the second contact 21 of the current-type relay is closed, the local control unit 22 issues an alarm.

[0022] In a preferred embodiment, the other end of the generator rotor shaft 16 and the other end of the control switch 13 are grounded to ensure safety during the operation of the electrical equipment.

[0023] In a preferred embodiment, a grounding resistance 17 is provided between the two grounding points of the generator rotor shaft 16 and the control switch 13. This ensures the stable operation of the power system and the personal safety of maintenance personnel.

[0024] In a preferred embodiment, the control switch 13 controls the connection and disconnection of the generator rotor carbon brushes and the secondary circuit of the rotor shaft, and can be manually controlled to connect to an alarm device.

[0025] In the preferred embodiment, when the generator rotor carbon brush 15 loses contact with the generator rotor shaft 16, the current-type relay 11 in the secondary circuit of the generator rotor carbon brush and rotor shaft is not energized, the second contact 21 of the current-type relay connects the alarm circuit, and the local control unit 22 in the alarm circuit issues an alarm signal, without relying on manual inspection to confirm whether the length of the generator rotor carbon brush 15 needs to be replaced.

[0026] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The embodiments and features described in this application can be arbitrarily combined without conflict. The protection scope of this utility model should be defined as the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. An alarm device reflecting the contact condition of generator rotor carbon brushes, characterized in that: It includes the generator rotor carbon brush and rotor shaft secondary circuit and alarm circuit; the generator rotor carbon brush and rotor shaft secondary circuit and alarm circuit are electrically connected through a current-type relay (11). When the current-type relay (11) is energized, the generator rotor carbon brush and rotor shaft secondary circuit are connected, and when it is not energized, the alarm circuit is connected.

2. A warning device for indicating the condition of the carbon brush contact of a generator rotor as claimed in claim 1, characterized in that: The secondary circuit of the generator rotor carbon brush and rotor shaft includes a power supply (12), a control switch (13), a resistor (14), a current relay (11), a generator rotor carbon brush (15), and a generator rotor shaft (16). One end of the generator rotor carbon brush (15) is in contact with the generator rotor shaft (16), the other end of the generator rotor carbon brush (15) is electrically connected to one end of the current relay (11), the other end of the current relay (11) is electrically connected to one end of the resistor (14), the other end of the resistor (14) is electrically connected to the positive terminal of the power supply (12), and the negative terminal of the power supply (12) is electrically connected to the control switch (13).

3. The alarm device for reflecting the contact condition of the carbon brush of the generator rotor according to claim 1, characterized in that: The alarm circuit includes a second contact (21) of a current-type relay and a local control unit (22); the second contact (21) of the current-type relay and the local control unit (22) are electrically connected to form a circuit.

4. The alarm device for reflecting the contact condition of the carbon brush of the generator rotor according to claim 2, characterized in that: The other end of the generator rotor shaft (16) and the other end of the control switch (13) are grounded.

5. A warning device for indicating the condition of the carbon brush contact of a generator rotor as claimed in claim 4, characterized in that: There is a grounding resistance (17) between the two grounding points of the generator rotor shaft (16) and the control switch (13).

6. A warning device for indicating the condition of the carbon brush contact of a generator rotor as claimed in claim 2, characterized in that: The control switch (13) controls the connection and disconnection of the generator rotor carbon brush and the secondary circuit of the rotor shaft.

7. The alarm device for indicating the contact condition of the carbon brush of a generator rotor according to claim 1, characterized in that: The generator rotor carbon brush (15) loses contact with the generator rotor shaft (16), the current relay (11) in the secondary circuit of the generator rotor carbon brush and the rotor shaft is not energized, the second contact (21) of the current relay connects the alarm circuit, and the local control unit (22) in the alarm circuit issues an alarm signal.

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