JPH02218801A - Oil supply device for turbine - Google Patents

Abstract

PURPOSE:To prevent decrease of bearing hydraulic pressure after test operation in a device having a main oil pump and an emergency oil pump parallelly arranged to each other by adding a testing switch independently on an operation sequence means of the emergency oil system, and setting the pressure of the emergency oil pump to be a specified value or lower at the time of testing. CONSTITUTION:In an oil supply device provided with a main oil system 1, an auxiliary oil system 2 and an emergency oil system 4, a testing switch 40 which is actuated at the time of operation test of an emergency oil pump 11 is arranged. While the switch 40 is set ON, a relay 41 is excited to open a contact 42 thereof. A three-way valve 5 is operated, while a relay contact 43 is closed by the output from an automatic starting pressure switch 6, so that a contact 45 of a relay 44 is entirely closed. Electric current is thus supplied through a resistance 46 to a motor 47 of the emergency oil pump 11. After a certain period of time passed, a contact 50 of a relay 49 with a timer is closed, thereby a contact 52 of a relay 51 is closed. Electric current is then supplied to the motor 47 bypassing a part of the resistance 46, and the output of the pump 11 is set to be a specified value or lower.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is applicable to steam power turbines for power generation, control, r, If
This invention relates to a turbine oil supply device that supplies f oil.

(Prior art) Conventionally, this type of turbine oil supply 1! For example, as shown in Figure 2, there is a main oil system 1 for lubricating the turbine during normal operation, and an auxiliary oil system 2 connected in parallel to the main oil system 1.
and ° An emergency oil system 4 connected in parallel via a bearing oil pressure regulating valve 3 downstream of these confluence points, a three-way valve 5 and an automatic start pressure switch connected downstream of these confluence points. 6, which are activated by sequence control.
Stops, etc. are now taking place.

During normal operation of the turbine, the main oil pump 7 of the main oil system 1 operates to supply necessary control oil, bearing oil, etc. to the turbine. The oil discharged from the main oil pump 7 passes through the main oil pump check valve 8, and part of it becomes control oil, and the other part becomes bearing oil after being depressurized in the bearing oil pressure regulating valve 3.

When the turbine is started or when the main pump 7 fails, the auxiliary pump 9 of the auxiliary oil system 2 is activated, and necessary lubricating oil is supplied via the oil pump check valve 10.

Roughly speaking, if both the main oil pump 7 and the auxiliary oil pump 9 stop working due to a failure, etc., the emergency oil pump 11 of the emergency oil system 4 operates and supplies only the bearing oil until the turbine stops. Supplied via pump check valve 12.

When the main oil pump 7 and the auxiliary pump 9 malfunction and the bearing oil pressure drops, the automatic start pressure switch 6 detects the oil pressure drop and sends an operation command signal to the operation sequence means of the emergency oil system 4. Output.

FIG. 3 shows a circuit diagram of the operation sequence control means for the emergency oil system 4. The circuit consists of 3 relays, 3 timer relays, 9 relay contacts, 2 switches, and 1
It consists of two resistors and a motor for operating the emergency oil pump.

The output from the self-starting pressure switch 6 closes the relay contact 20, which excites the relay 21, closes the relay contact 22, and current flows through the resistor 23 to the motor 24, which starts the motor 24 of the emergency oil pump 11. to start. At the same time, relay contact 25 closes, and timer-equipped relay 26
is excited, and closes the relay contact 27 after a certain period of time has elapsed. As a result, the relay 28 is energized, the relay contact 29 is closed, and the current flowing to the motor 24 bypasses a portion of the resistor 23. At the same time, the timer relay 30 is energized, and after a certain period of time, the relay contact 31 is closed and the relay 32 is activated.
is excited. This closes the relay contact 33, the current flowing to the motor 24 bypasses all the resistors 23, the rated current flows to the motor 24, and the motor 24
operates at the rated rotation speed. Relay 3 with timer at the same time
4 is energized, and after a certain period of time elapses, the relay contact 35 is opened, the relay contact 36 is opened, and the timer-equipped relay 26 is demagnetized.
Relay contact 27 opens. Then, the relay 28 and the relay with timer 30 are demagnetized, and the relay contact 29 and the relay contact 3 are demagnetized.
1 opens. Relay contact 35 is held as is. The motor 24 is stopped by turning the switch 37.

(Problem to be Solved by the Invention) In such a lubricating oil supply device, when the main oil pump 7 breaks down, the auxiliary oil pump 9 and the emergency oil pump 11 are always ready to operate. It is necessary. For this reason, operation tests are conducted from time to time to confirm the operable state. Since this operation test is carried out during normal operation of the turbine, it is operated in conjunction with the main pump 7.

Here, at the end of the operation test, the main oil pump 7 is in independent operation, so oil pressure fluctuations occur and the oil pressure decreases. To prevent this, the auxiliary oil pump 9 is designed to have a cut-off pressure lower than the operating point pressure of the main pump 7. The emergency oil pump 11 is designed so that its shutoff pressure is lower than the pressure at the downstream use point of the bearing oil pressure regulating valve 3.

However, since the auxiliary oil pump 9 is generally operated by AC power, the cut-off pressure conforms to the design value, whereas the emergency oil pump 11
Generally, a DC power supply is used, and this DC power supply has a fixed capacity to supply all other emergency equipment, so for the emergency pump during the operation test,
The voltage from the C power source becomes concentrated and becomes high, and the rotation speed of the emergency oil pump 11 becomes high. Therefore, if the cut-off pressure becomes higher than the design value and becomes equal to or higher than the pressure at the downstream use point of the bearing oil pressure regulating valve 3, there is a possibility that a bearing oil pressure drop trip will occur at the end of the operation test. there were. For this reason, there remained a possibility that the emergency pump 11 could not be tested for operation during normal operation of the turbine.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a turbine oil supply device that allows an emergency pump operation test to be performed without causing a bearing oil pressure drop trip during normal operation of the turbine. With the goal.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a turbine with &1J during normal operation of the turbine.
A main oil pump that supplies oil for tllll and lubricating;
An emergency oil pump is connected in parallel to the main oil pump and is started in place of the main oil pump in an emergency. ,lJ
In a turbine oil supply system whose startup can be controlled by TLL during normal operation, the circuit component for sequence training of #7 emergency pump is a testing device that is independent of the emergency startup switch. The pump is characterized in that it has a switch and an output control section for interrogating an output that is lower than a certain level than an output for emergency activation of the emergency pump.

(Function) According to the present invention, an independent switch for testing the emergency oil system is provided in the pump testing circuit component, and the output of the emergency pump is kept below a certain value during testing. Therefore, the amount of oil discharged from the emergency oil pump can be controlled during the operation test, and there is no possibility that the bearing oil pressure will drop at the end of the operation test.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Furthermore, since the target oil pump enclosure remains the same as before,
Please refer to FIG. 2 as well.

FIG. 1 shows the circuit configuration of the operation sequence means of this embodiment. This circuit consists of 4 relays, 3 relays with timers, 10 relay contacts, 3 switches, 1 resistor, and a motor for operating the emergency oil pump. That is, in this circuit, a dedicated switch 40 is provided to start the emergency oil pump 11 during an operation test, and by closing this switch 40, the relay 41 is energized and the relay contact 42 is turned on. It has become. In this state, the three-way valve 5 (see Figure 2)
, the output from the automatic starting pressure switch 6 closes the relay contact 43, which energizes the relay 44 and opens the relay contact 45. The TI current flows to start the motor 47. At the same time, relay contact 48
The relay 49 with a timer is energized and the relay contact 50 is closed after a certain period of time has elapsed. As a result, the relay 51 is energized, the relay contact 52 is closed, and the current flowing to the motor 47 bypasses a portion of the resistor 46 . At the same time, the timer-equipped relay 53 is energized, and the relay contact 54 is closed after a certain period of time has elapsed. Here, since the relay contact 42 is open, the relay 55 is not excited, and the relay contact 56 for bypassing the resistor 46 is also kept open. Therefore, no rated current flows through the motor 47, and the motor 47 does not reach its rated rotation speed. For this reason, the amount of oil m discharged from the emergency oil pump 11 during the operation test will not become excessive, and therefore a hydraulic pressure drop trip will not occur at the end of the operation test. The reference numerals @57 and 58 are relay contacts that are closed after a certain period of time by the excitation of the timer relay 56, and the reference numeral 59 is a motor stop switch.

Note that if the rotational speed of the motor 47 is set in advance to a rotational speed higher than the rotational speed that secures the minimum amount of oil necessary for turbine lubrication, the main oil pump 7 may malfunction during the operation test, and the emergency oil pump 11 may not start. Even if a situation occurs, the amount of oil necessary for the turbine can be secured.

〔Effect of the invention〕

As described above, according to the present invention, an independent test switch is added to the emergency oil system operation sequence means, and the output of the emergency pump is kept below a certain level during the test. This has the effect of allowing safe testing of emergency oil pumps at the beginning of the year without the risk of lower bearing oil pressure later.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the turbine oil supply device according to the present invention, and Fig. 2 is a circuit diagram showing the operation sequence means of the emergency oil system, Fig. 2 is a system diagram showing the oil pump system, and Fig. 3 is a conventional circuit diagram. 1... Main oil system, 2... Auxiliary oil system, 3... Bearing oil pressure adjustment valve, 4... Emergency oil system, 5... Three-way valve, 6...
・Automatic start pressure switch, 7...Main oil pump, 8.
・・Main oil pump check valve, 9・・Auxiliary pump, 10・・
・Auxiliary pump check valve, 11...Emergency oil pump, 12
...Emergency oil pump check valve, 40.59...Switch, 41.44.51.55...Relay, 49.53
．． 56...Relay with timer, 42.43.45.4
8.50.52.54.56,,57.58...Relay contact, 46...Resistor, 47...Motor

Claims (1)

[Claims] A main oil pump that supplies control and lubricating oil to the turbine during normal operation of the turbine, and an emergency oil pump that is connected in parallel to the main oil pump and is activated in place of the main oil pump in an emergency. In a turbine oil supply system in which the emergency oil pump can be started during normal operation by sequence control for a start-up test, a circuit component for performing sequence control of the emergency pump is , a turbine characterized in that it has a test switch independent from an emergency start switch, and an output control section for controlling the output to a certain value or less than the emergency start output of the emergency pump. Oil supply device.