Gas turbine starter

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a gas turbine starting device capable of starting a gas turbine having a starting DC motor with an AC power source.

【0002】

[Conventional technology]

The gas turbine starting device is generally equipped with a starting device such as a DC motor, an air turbine, an AC motor, a hydraulic motor, etc., and drives the starting device to rotate the gas turbine rotor when the gas turbine is started. Are known. Here, the air turbine requires a large-scale compressed air device, and the AC motor and the hydraulic motor require an AC power supply that may cause a power failure. For this reason, small gas turbines often employ a DC motor as a starter, which uses a storage battery that has relatively simple equipment and can secure a power source even when a commercial power source fails.

【0003】

[Problems to be Solved by the Invention]

However, the storage battery, which is the power source of the DC motor, requires careful maintenance such as inspection and replacement in order to prevent performance deterioration due to aged deterioration, and its maintenance is quite troublesome. In addition, if an AC power supply can be secured with an emergency power supply device, a starting device using an AC motor can be adopted, but in this case, an inverter device is required separately to control the characteristics suitable for starting the gas turbine. It becomes structurally complicated.

【0004】

The present invention has been made in view of the above circumstances, so that the gas turbine can be started by using an AC power supply with a mechanism simpler than that of an inverter without changing the DC motor mounted on the gas turbine at all. It is an object of the present invention to provide a gas turbine starting device.

【0005】

[Means for solving problems]

The invention according to claim 1 includes an AC / DC power supply device that converts an AC power supply into an appropriate DC power supply as a starting characteristic of the gas turbine, and the DC current output from the AC / DC power supply device is attached to the gas turbine. It is a gas turbine starting device characterized in that it is supplied to a starting DC motor.

【0006】

As a result, by connecting the AC / DC power supply to the AC power supply and connecting this AC / DC power supply to the DC motor, the DC current appropriate for the starting characteristics of the gas turbine output from this AC / DC power supply. Can be supplied to a DC motor to start a gas turbine.

【0007】

According to the second aspect of the present invention, the AC / DC power supply device includes a switchable current limiter that limits the current by a resistor or a coil, a transformer connected to the secondary side of the current limiter, and the like. The gas turbine starting device according to claim 1, further comprising a rectifying element connected to the secondary side of the transformer.

【0008】

As a result, the AC power input to the AC / DC power supply is controlled to a current suitable for starting the gas turbine via a current limiter, transformed to the required voltage by the transformer, and then converted to DC current by the rectifying element. By outputting the current, the gas turbine can be started while preventing excessive torque transmission to the starting mechanism, and by switching the current limiter, the characteristics required for starting the gas turbine can be easily set.

【0009】

The invention according to claim 3 is the gas turbine starting device according to claim 2, wherein a plurality of the current limiters are connected in series to each line extending from the AC power supply. Thereby, by switching the combination of the current limiters, for example, the optimum current characteristics can be obtained for the starting characteristics of different gas turbines.

【0010】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a system diagram of a gas turbine starting device according to an embodiment of the present invention, which comprises an AC / DC power supply 12 connected to an AC power source 10, wherein the AC / DC power supply 12 is provided. , It is connected to the starting DC motor 16 attached to the gas turbine 14. A drive gear 18 is fixed to the output shaft of the starting DC motor 16, a driven gear 22 is fixed to the gas turbine rotor 20 extending inside the gas turbine 14, and an intermediate gear 24 meshes with these gears 18 and 22. ing.

【0011】

As a result, the AC current supplied from the AC power supply 10 is converted into a DC current by the AC / DC power supply device 12, and this DC current is supplied to the DC motor 16 to drive the motor 16 to rotate the gas turbine rotor 20. As a result, the gas turbine 14 is accelerated and started.

【0012】

FIG. 2 shows a circuit configuration diagram of the AC / DC power supply device 12 shown in FIG. 1. The AC / DC power supply device 12 has a current connected in series to each line extending from the input AC power supply 10. The limiters 30a and 30b and electromagnetic contactors 32a and 32b connected in parallel to the current limiters 30a and 30b are provided. The current limiters 30a and 30b are configured to limit the current flowing inside by a resistor or a coil, and when the magnetic contactors 32a and 32b are open, the current flowing downstream by the current limiters 30a and 30b is generated. It is restricted, and this restriction is released when the magnetic contactors 32a and 32b are closed.

【0013】

The secondary side of the current limiter 32b located on the downstream side is connected to the primary side of the transformer 34 that transforms to the required voltage, and the secondary side of this transformer 34 rectifies the AC current to a DC current. The rectifier 36 is connected. As a result, the DC current rectified by the rectifier 36 is output from the AC / DC power supply device 12 and supplied to the DC motor 16 (see FIG. 1).

【0014】

Next, a case where the AC / DC power supply unit 12 obtains a required DC current according to the starting characteristics of the gas turbine 14 will be described with reference to FIG. FIG. 3 shows the DC current at the time of starting the gas turbine 14 when the output (DC current) of the AC / DC power supply device 12 is supplied to the DC motor 16 and the acceleration characteristics of the gas turbine (gas turbine rotor 20). (Rotation speed of) is shown.

【0015】

First, at the beginning of the start, all the magnetic contactors 32a and 32b are opened so that the low AC current is input from the transformer 34 to the rectifier 36 through the current limiters 30a and 30b, and the low DC current is input to the DC motor. Supply to 16. Then, when the rotation speed of the gas turbine rotor 20 reaches a predetermined value, for example, one electromagnetic contactor 32a connected in parallel to the current limiter 30a located on the upstream side is closed, thereby this current limiter. A higher DC current is supplied to the DC motor 16 by bypassing 30a and allowing an AC current to flow. When the rotational speed of the gas turbine rotor 20 further increases and reaches a predetermined value, the other electromagnetic contactor 32b connected in parallel with the current limiter 30b located on the downstream side is also closed, thereby limiting both currents. An even higher direct current is supplied to the direct current motor 16 by allowing an alternating current to flow by bypassing the vessels 30a and 30b.

【0016】

As a result, at the beginning of starting, the electromagnetic contactors 32a and 32b are opened and a low current is supplied to the DC motor 16 through the current limiters 30a and 30b to avoid excessive torque, and the electromagnetic contactors 32a respond to the acceleration of the gas turbine. By sequentially closing and 32b and supplying a higher current to the DC motor 16, sufficient torque required for acceleration can be obtained. By changing the resistance and the capacitance of the coil to be combined via the current limiter, it is possible to obtain the optimum DC current and acceleration characteristics for the starting characteristics of different gas turbines.

【0017】

In this embodiment, an example in which two current limiters are connected in series to each line extending from the AC power supply is shown, but the number of the current limiters may be one or three or more. That is, the number of current limiters may be determined so that an appropriate DC current can be supplied to the DC motor at the time of starting from the starting characteristics of the gas turbine and the characteristics of the DC motor.

【0018】

[Effect of the invention]

As described above, according to the present invention, by connecting an AC / DC power supply device to an AC power supply and connecting the AC / DC power supply device to a DC motor, the AC / DC power supply device can be connected without using an inverter device. The gas turbine can be started by supplying an appropriate direct current to the DC motor as a starting characteristic of the gas turbine output from the DC power supply device.

【0019】

Moreover, the AC power input to the AC / DC power supply is controlled to a current suitable for starting the gas turbine via a current limiter, transformed to the required voltage by the transformer, and then converted to DC power by the rectifying element. By outputting, the gas turbine can be started while preventing excessive torque transmission to the starting mechanism, and by switching the current limiter, the characteristics required for starting the gas turbine can be easily set.

[Simple explanation of drawings]

[Figure 1]

It is a system diagram of the gas turbine starter of the Embodiment of this invention.

[Figure 2]

It is a circuit block diagram of the AC / DC power supply device shown in FIG.

[Fig. 3]

It is a graph which shows the DC current and acceleration characteristic (gas turbine rotor rotation speed) at the time of starting operation of a gas turbine using the gas turbine starter shown in FIG.

[Explanation of symbols]

10 AC power supply 12 AC / DC power supply 14 gas turbine 16 DC motor 18 drive gear 20 gas turbine rotor 22 Driven gear 24 Intermediate gear 30a, 30b each current limiter 32a, 32b Electromagnetic contactor 34 transformer 36 Rectifier