JPH018667Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a power supply device for a starter motor of a gas turbine.

Gas turbines have the advantages of excellent operational reliability and maintainability, and are lightweight and compact.
In recent years, it has become widely used as a prime mover for power generation and rotating machinery. The gas turbine is started as follows. First, the main shaft of the gas turbine is accelerated by the starter. When the compressor attached to the main shaft accelerates the combustion chamber until sufficient air is supplied to the combustion chamber, fuel is supplied to the combustor and ignited by the spark from the ignition plug. The air heated by the combustion of the fuel is guided to a turbine attached to the main shaft, expands, and causes the turbine to generate power. Furthermore, when the gas turbine is accelerated to a speed exceeding the speed at which it can accelerate on its own, the starter is disconnected and the gas turbine reaches its rated speed. Incidentally, the starter motor used in the starter of a gas turbine is a series motor, and has the characteristic that a large current flows during startup, and the current rapidly decreases as the rotational speed increases. For this reason, since it is necessary to limit excessive current at the time of starting, the starter motor cannot generate a sufficiently effective output, resulting in a drawback that it takes a long time to start the gas turbine.

The present invention has been made in view of the above circumstances, and its purpose is to provide a power supply device for a starter motor that can rapidly start a gas turbine even with a small capacity starter motor. Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.
Reference numeral 1 in the figure indicates a charger, and the output terminal p of this charger 1 is connected to one end of the B contacts 2a and 2b of the contactor 2, and the other ends of the contacts 2a and 2b are connected to the terminals of the storage batteries E1 and E2, respectively. It is connected. The output terminal n of charger 1 is connected to contactor 2.
One end of the b contact 2c is connected to the terminal of the storage battery E2, and the other end of the b contact 2c is connected to the terminal of the storage battery E1. Further, a contacts 3a and 3b of the contactor 3 are connected between the terminals of the storage battery E1 and the terminals of the storage battery E2, and between the terminals of the storage battery E1 and the terminals of the storage battery E2, respectively, and the terminals of the storage battery E1 and the storage battery E2 are connected to each other. A contact 4a of the contactor 4 is connected between the terminals. Furthermore, the terminal of the storage battery E2 is the a contact 5 of the contactor 5.
A contacts 3d of the contactors 3 and 4 are connected to the anode side of the diode D through the a, and a contacts 3d of the contactors 3 and 4 are connected between the cathode side of the diode D and the terminal of the storage battery E1.
4b are connected in parallel. and,
These a contacts 3a, 3b, 3d, 4a, 4b,
5a, b contacts 2a, 2b, 2c, and diode D constitute a storage battery connection switching circuit (connection switching circuit) X, and starter motor M is connected between the cathode side of diode D and the terminal of storage battery E2.

The terminal of the storage battery E2 is further connected to one end of the switch 6, and the other end is connected to one end of each of the contact b contacts 8a of the contactor 2, the contactor 5, and the relay 8. The other end of the b contact 8a is connected to one end of the contactor 3, and the other end of the contactor 3 is connected to a terminal of the storage battery E2. The other ends of the contactors 2 and 5 are also connected to terminals of the storage battery E2. moreover,
The terminal of the storage battery E2 is connected to one end of the switch 7, and the other end of the switch 7 is connected to the b contact 3 of the contactor 3.
It is connected to one end of the contactor 4 via c and also to one end of the relay 8. The other end of contactor 4 and relay 8 is connected to storage battery E.
It is connected to the second terminal. The above switch 6,
7. A contactor control circuit Y is constituted by the contactors 2, 3, 4, and 5, the relay 8, and the b contacts 3c and 8a.

Next, the operation of the gas turbine cell motor power supply device configured as described above will be explained.

First, close switch 6. Then, contactor 2, contactor 3, and contactor 5 are excited.
When the contactor 2 is excited, the b contacts 2a, 2b,
2c opens, and the connection between the charger 1 and the charging circuits of the storage batteries E1 and E2 is cut off. These are storage batteries E1 and E2
This prevents an excessive voltage from being applied between the output terminals p and n of the charger 1 when the two are connected in series. When the contactor 3 is energized, the a contacts 3a, 3b, 3d of the contactor 3 close and the storage battery E
1 and E2 are connected in parallel, and the b contact 3c of the contactor 3 is opened to prevent a short-circuit accident due to the contactor 3 and the contactor 4 being turned on at the same time. Furthermore, the a contact 5a is closed by the excitation of the contactor 5, and the circuit of the diode D can be energized. Electricity is then supplied to the starter motor M from the storage batteries E1 and E2 connected in parallel, and the starter motor M is connected to the gas turbine via a clutch and starts rotating to accelerate the gas turbine. Figure 2 shows changes in the rotational speed of the gas turbine and the current of the cell motor M, and the current is e
changes along the curve.

When the switch 7 is closed when the rotational speed of the gas turbine reaches N1, the relay 8 is energized and the b contact 8a is opened. Then contactor 3 is demagnetized,
The a contacts 3a, 3b, 3d open and the connection between storage batteries E1 and E2 is cut off. A contact 5 of contactor 5
Since a remains closed, cell motor M is connected to storage battery E2.
is supplied with power through the diode D circuit, and the starter motor M is not disconnected from the gas turbine.
Continue driving. Furthermore, b contact 3c of contactor 3
is closed, the contactor 4 is energized, and the a contacts 4a,
4b is closed and the storage batteries are connected in series. Then, a voltage twice as high as that of one set of storage batteries is applied to the starter motor from the storage batteries E1 and E2, and the current of the starter motor M changes along the curve 2e in FIG. 2. The gas turbine is thereby accelerated even more rapidly. During this time, diode D prevents current from flowing backward.
When the switch 7 and switch 6 are opened when the gas turbine reaches the rotational speed N2 at which it can accelerate on its own, the contactor 4, contactor 5, and relay 8 are demagnetized, the a contacts 4a, 4b, and 5a are opened, and the power to the starter motor M is turned on. The starter motor M is disconnected from the gas turbine and stopped. At the same time, the contactor 2 is demagnetized, the b contacts 2a, 2b, and 2c are closed, and the storage battery is placed in a charging state.

Note that the diode D in this embodiment may be replaced with a resistor, or a resistor and a diode may be connected in series.

As explained above, the present invention consists of two sets of storage batteries that supply power to the starter motor of the gas turbine, and a connection switching circuit that switches the connection of the two sets of storage batteries while maintaining power supply to the starter motor. Even if a starter motor with a smaller capacity than the starter motor used in the past is used, the starting current can be kept low and accidents caused by excessive current can be prevented. This has the excellent effect of realizing faster startup of the gas turbine by switching the connection. Furthermore, this starter motor power supply device can also supply a constant voltage control power source for the contactor control circuit, so it has the advantage that there is no need to separately prepare a control power source.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing one embodiment of the present invention;
The figure is a state diagram illustrating current changes in the starter motor according to the present invention. E1... Storage battery, E2... Storage battery, M... Cell motor, X... Storage battery connection switching circuit (connection switching circuit).

Claims (1)

[Scope of utility model registration request] It consists of two sets of storage batteries that supply power to the cell motor of the gas turbine, and a connection switching circuit that switches the connection of the two sets of storage batteries while maintaining power supply to the cell motor, and connects the storage batteries in parallel or series by an external command signal. A power supply device for a starter motor of a gas turbine, characterized in that it is connected to change the voltage supplied to the starter motor.