JP3322919B2 - Variable speed pumped storage power plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable-speed pumped-storage power plant in which the size of a harmonic absorption filter installed underground is reduced.

[0002]

2. Description of the Related Art In recent years, pumped storage power plants have been increasing in capacity in response to nuclear power plants, and have tended to have high heads and high speeds in terms of location and efficiency of pump turbines.

[0003] Generally, in a pumped storage power plant, the opening of a flow control valve is controlled to an appropriate flow according to a head for the purpose of adjusting output during power generation. Is a constant synchronous machine, so efficiency cannot be improved. In addition, since the rotation speed is constant during pumping, the input from the system cannot be adjusted due to the characteristics of the pump turbine.

Therefore, recently, an AC variable speed system in which an AC-excited generator motor having a wound rotor is applied instead of the synchronous machine and a converter is connected to the rotor side has been adopted.

FIG. 2 shows an example of the construction of a pumped storage power plant using this AC variable speed system. In FIG. 2, 1 is a pump turbine, 2 is a generator motor mechanically connected directly to the pump turbine 1, and a parallel circuit breaker 3 is connected to a stator winding of the generator motor 2; 3
Are connected to the bus 6 via a disconnector 4 for power generation operation and a disconnector 5 for pumping operation connected in parallel. Further, between the rotor winding of the generator motor 2 and the busbar 6, there are a converter 7, a power transformer 8 for the converter, and a power circuit breaker 9 for the converter.
Are connected in series. The above-mentioned equipment is installed underground because pumping power generation facilities are often located in mountainous areas, where there are civil engineering restrictions and consideration must be given to the surrounding environment.

On the other hand, the bus 6 is composed of a power cable 10, a main transformer 11, and a transmission line side circuit breaker 1 for transmitting power to the transmission line during power generation operation and receiving power from the transmission line during pumping operation.
2 and connected to a transmission line 13. Here, the main transformer 11 and the transmission line side circuit breaker 12 are all installed at the above-ground switchyard, and connect the underground and the ground with the power cable 10.

In the variable speed pumped storage power plant having such a configuration, the power transmission line side circuit breaker 12, the parallel circuit breaker 3 and the power supply circuit breaker 9 for the converter are all turned on during operation, and the power generation circuit breaker is operated during power generation operation. The disconnector 4 is turned on, and the pumping operation disconnector 5 is turned on in the pumping operation, and the converter 7 excites the rotor of the generator motor 2 by AC excitation to perform variable speed operation.

In this case, electric power is transmitted from the stator winding of the generator motor 2 to the transmission line 13 during the power generation operation, and power is supplied to the stator winding of the generator motor 2 from the transmission line 13 during the pumping operation. .

In such a variable-speed pumped-storage power plant, the alternating current supplied from the converter 7 to the rotor winding of the generator motor 2 during operation includes harmonics due to the characteristics of the converter. The voltage on the stator side of the generator motor 2,
The current also contains harmonics. For this reason, the harmonic absorption filter 14 is connected to the stator side of the generator motor 2 via the filter circuit breaker 17 to reduce the adverse effects of harmonics on various devices of the variable speed pumped storage power generation equipment, and to reduce the power transmission line. The distortion of the voltage / current waveform is reduced.

[0010]

However, since this harmonic filter 14 has a very large size, a sufficient installation space must be secured underground in order to install it underground. This leads to an increase in underground excavation work costs, and there is a case where a sufficient installation space cannot be secured due to civil engineering restrictions depending on the location, which is not preferable.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a variable speed pumped storage power plant capable of reducing the size of a harmonic absorption filter installed underground and reducing its installation space.

[0012]

In order to achieve the above object, the present invention provides a generator motor having a wound rotor and a converter connected to the wound rotor and supplying a variable frequency alternating current. In a variable speed pumped storage power plant having a switchgear installed on the ground that connects the output end of the generator motor to a transmission line, a filter for absorbing higher harmonics generated by the converter is provided with a higher harmonic absorption filter. A filter and a low-order harmonic absorption filter, wherein the high-order harmonic absorption filter is connected between an output terminal of the generator motor and a power cable, and the low-order harmonic absorption filter is connected to a power cable and the transmission line. It is designed to be connected between

[0013]

In the variable speed pumped storage power plant having such a configuration, the filter for absorbing the harmonics generated by the generator motor is divided into a high-order harmonic absorption filter and a low-order harmonic absorption filter. A high-order harmonic absorption filter that absorbs high-order harmonics that are likely to cause inductive interference is installed underground close to the source of harmonics, and absorbs low-order harmonics that are less harmful than high-order harmonics Since the absorption filter is installed on the ground, it is possible to minimize the filter installation space required underground.

[0014]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the configuration of a variable speed pumped storage power plant according to the present invention. The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted. Only different points will be described here. In the conventional configuration shown in FIG. 2, the harmonic filter 14 is provided on the stator side of the generator motor 2, but in the present embodiment, as shown in FIG. High-order harmonic absorption filter 1
5 is connected to the stator side of the generator motor 2 underground via a circuit breaker 17 for high-order harmonic absorption filter, and the low-order harmonic absorption filter 16 is connected to the low-voltage side of the main transformer 11 on the ground side. The configuration is such that the connection is made via the breaker 18 for the wave absorption filter. In this case, the individual dimensions and overall size of the high-order harmonic absorption filter 15 and the low-order harmonic absorption filter 16 are smaller than those of the conventional harmonic absorption filter 14, respectively.

With such a configuration, high-order harmonics that easily cause an induction failure are absorbed by the high-order harmonic absorption filter 15 provided in the vicinity of the generator motor 2 as the generation source. The low-order harmonics are absorbed by the low-order harmonic absorption filter 16 installed on the ground, and
Voltage / current waveform distortion is reduced.

As described above, in this embodiment, the high-harmonic absorption filter is divided into a high-order harmonic filter and a low-order harmonic filter.
Since only the low-order harmonic absorption filter 16 is provided above the ground, the installation space underground can be reduced.

In the above-described embodiment, the high-order harmonic absorption filter 15 is provided on the stator side of the generator motor 2. However, the filter 15 is connected to the parallel circuit breaker 3, the generator disconnector 4, and the pumping disconnector. 5 may be connected to the main circuit, or may be connected to the bus 6. In the present embodiment, the low-order harmonic absorption filter 16 is provided on the low voltage side of the main transformer 11, but it may be provided on the high voltage side of the main transformer 11.

[0019]

As described above, according to the present invention, the high-harmonic absorption filter is divided into a high-order harmonic filter and a low-order harmonic filter. A variable-speed pumped-storage power plant that has only a filter and installs a low-order harmonic absorption filter on the ground, which can reduce the installation space underground and contribute to a reduction in underground excavation work costs Equipment can be provided.

[Brief description of the drawings]

FIG. 1 is a main circuit configuration diagram showing one embodiment of a variable speed pumped storage power plant according to the present invention.

FIG. 2 is a main circuit configuration diagram showing a conventional variable speed pumped storage power plant.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pump turbine 2 ... Generator motor 3 ... Parallel circuit breaker 4 ... Generation operation disconnector 5 ... Pumping operation disconnector 6 ... Bus 7 ... Conversion device 8 .... Power transformer for converter, 9 ... Power breaker for converter, 10 ...
Power cable, 11 Main transformer, 12 Circuit breaker on transmission line, 13 Transmission line, 14 Harmonic absorption filter, 15 High-order harmonic absorption filter, 16 Low-order harmonic Absorption filter.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mitsuyuki Abe 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electric Power Company (72) Inventor Hirokazu Kaneko 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Inside Electric Power Company (72) Inventor Ryoji Sugawara 6-15-1, Ginza, Chuo-ku, Tokyo Inside Power Development Co., Ltd. (72) Inventor Fujio Osawa 6-15-1, Ginza, Chuo-ku, Tokyo Inside Power Development Co., Ltd. (72) Inventor Ikuo Furuno 1 Toshiba-cho, Fuchu-shi, Tokyo Inside the Toshiba Fuchu factory (56) References JP-A-4-121100 (JP, A) JP-A-60-59978 (JP, A) ( 58) Field surveyed (Int. Cl. ⁷ , DB name) H02J 3/01 H02J 15/00 H02P 9/04

Claims (1)

(57) [Claims] 1. A generator motor having a winding rotor and a converter connected to the winding rotor and supplying a variable frequency alternating current are installed underground, and an output end of the generator motor is connected to a transmission line. In a variable speed pumped storage power plant in which a switching station is installed on the ground, a filter that absorbs harmonics generated by the conversion device is configured as a high-order harmonic absorption filter and a low-order harmonic absorption filter, and A harmonic absorption filter is connected between an output end of the generator motor and an underground electric line of the switchyard, and the low-order harmonic absorption filter is connected between the switchyard and an electric line of the transmission line. Characteristic variable speed pumped storage power plant.