JP2641358B2 - Variable speed pumped storage power generation system - 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 generation system that operates an AC excitation synchronous machine under the control of an excitation converter.

[0002]

2. Description of the Related Art FIG. 2 is a circuit diagram showing a conventional variable speed pumping system. In the drawing, reference numeral 1 denotes an armature of an AC excitation synchronous machine (hereinafter referred to as AESM) 50, and 2 denotes an AESM 50.
, A reversible pump turbine directly connected to the rotor 2, 4 a shaft, 5 a transformer for an exciting converter, 6 a thyristor drive circuit for controlling the exciting current of the secondary coil. An excitation converter (hereinafter, referred to as EX), which is composed of EX, is a controller for EX6.

Next, the operation will be described. AESM50
In order to operate the AES at variable speed, a method of secondary excitation of the AESM50 is usually adopted. Even if the rotational speed changes, if the frequency is corrected by the secondary excitation by the slip so that it matches the system frequency, the system and the Can be operated in parallel.

In EX6, a cycloconverter system for directly generating an alternating current from an alternating current, or a system comprising an inverter and a converter for once converting to direct current is used.
The AESM 50 is operated so that the electric power taken by the EX 6 via the transformer for exciting converter 5 becomes the electric power set under the ignition control by the controller 7 and the optimum rotational speed.

[0005]

Since the conventional variable-speed pumped-storage power generation system is configured as described above, the system of FIG. 7 includes a thyristor and the like because the EX6 has a multi-phase group structure. The failure of some transducer elements makes it impossible to continue the operation of the AESM 50, that is, the failure of one element causes the loss of the excitation capability, and the AESM 50 has to be stopped continuously. .

[0006] The inventions of this has been made in order to solve the problems as described above, by devising a circuit system of EX, even if the failure of the transducer elements of a portion of the EX, continue the AESM It is an object of the present invention to obtain a variable speed pumped storage power generation system capable of realizing operation.

[0007]

Means for Solving the Problems A variable speed pumped storage power generation system according to the inventions of this, among the multiphase multi grouping the excitation transducer, disconnect the failed group of exciting transducer from the secondary side And an inverter control circuit that enables the secondary side to be excited by the remaining normal group of exciting converters.

[0008]

[Action] inverter control circuit in the inventions of this, when a group of exciting transducer multigroup configuration fails, after having continued to be operated with AC-excited synchronous machine with excitation transducer remaining groups The control of the excitation converter is also controlled by the remaining group,
The power generation is controlled within the power range that can be operated by the remaining groups.

[0009]

[Embodiment 1] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes an armature of an AESM50, 2 denotes a rotor having a secondary coil of the AESM50, 3 denotes a reversible pump turbine directly connected to the rotor 2, 4 denotes a shaft, and 5 denotes a shaft.
EX transformer 11 is a converter disconnector 15 and this
EX transformer connected in series with converter disconnector 15
5 connected to the primary side of the AESM 50
AESM5 through the inverter disconnector 14
An inverter connected to the secondary side of the inverter 0, 13 is a DC link capacitor, 14 is an inverter disconnector provided on the output side of the inverter 12, 15 is a converter disconnector provided on the input side of the converter 11, and 16 is an inverter It is a control circuit. Further, a system configuration is provided in which three groups of EX6 including the inverter 12 and the converter 11 are provided.

Next, the operation will be described. First, the inverter control circuit 16 is controlled so that the instructed power, reactive power, voltage and optimum rotational speed are obtained. On the other hand, independently of this, the converter output voltage and the conversion power factor of EX6 are set to 1.0. The converter 11 is controlled so as to perform the operation. In the present invention, since the EXs 6 are multi-grouped (here, three groups) in order to increase the capacity, current balance control between the EX 6 groups is required.

When the upper group EX6 of the three groups EX6 fails, for example, the inverter disconnector 14 and the converter disconnector 15 on the output side and the input side of the upper group EX6 are opened. AESM50 is excited by EX6 of the remaining middle group and lower group. Then, in the two groups of EX6, the commanded electric power within an allowable range,
The inverter 12 is controlled by the inverter control circuit 16 so that the reactive power, the voltage, and the optimum rotational speed are attained.
Enables continuous operation of M50. This operation is applicable to both the power generation operation and the pumping operation.

Embodiment 2 FIG. In the above embodiment, the EX6 has been described as a forced commutation type multi-phase multi-group gate turn-off (hereinafter referred to as GTO) type constituted by the inverter 12 and the converter 11, but may be a cyclo-converter type and the number of phases may be increased. When the number of groups is three or more and the number of groups is two or more, the same effects as those of the above embodiment can be obtained.

[0013] In this case, the concept of multi-grouping is based on a method in which a partial load operation is performed when a group of failures occurs, or a converter multi-group configuration with a group with a margin so that normal operation can be performed even after the failure group is separated in the case of a group failure. It is also possible to adopt a configuration that allows it.

[0014] Further, not limited to pumped storage power plants, general AES
The same effect can be obtained even when used in an application plant applying M, for example, a flicker prevention system using a flywheel generator.

[0015]

As evident from the foregoing description, according to the inventions of this, among the multiphase multi grouping the excitation transducer, disconnect the failed group of exciting transducer from the secondary side remains in the other Normal group encouragement
Since the inverter control circuit that allows excitation of the secondary side is provided by magnetizing converter, transducer elements of a portion of the excitation transducer
The AC excitation synchronous machine can be operated even if the
It is said that variable speed pumped storage power generation with high operation rate can be realized.
effective.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a variable speed pumped storage power generation system according to one embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional variable speed pumped storage power generation system.
FIG.

[Description of Signs] 5 EX transformer (transformer for excitation converter) 6 EX ( transformer for excitation) 11 converter 12 inverter 16 inverter control circuit 50 AESM (AC excitation synchronous machine)

Claims (1)

(57) [Claims] 1. A variable-speed pumped-storage power generation system that operates at a variable speed by controlling a secondary side of an AC excitation synchronous machine directly connected to a reversible pump-turbine by an excitation converter. On, through the inverter disconnector
Inverters and cores connected to the secondary side of the AC excitation synchronous machine
Connected in series with the inverter disconnector and this converter disconnector.
AC excitation via a transformer for excitation converter
Converter connected to primary side of synchronous machine, this converter
DC link connected in parallel between the inverter and the inverter
And a multi-phase converter.
Multiple groups and one of the excitation converters
In this case, the failure of the excitation converter
Release the inverter disconnector and the converter disconnector, and
AC excitation by another normal group of excitation converters
An inverter control circuit for exciting the secondary side of the synchronous machine
Variable speed pumped storage power generation system characterized by comprising a.