JPH06272990A - Generator system - Google Patents

Abstract

PURPOSE:To supply power responsive to utility while executing energy conservation by operating a heat generator at a variable speed. CONSTITUTION:A refrigerator 3 and a wound-rotor induction generator 4 having an exciter 6 are interlocked and connected to one prime mover 1, a temperature of heat output from the refrigerator 3 is measured by a temperature sensor 12, and a speed of the mover 1 is so controlled as to maintain the temperature of the measured heat within a set range. On the other hand, frequency and voltage, or reactive power and effective power to be output from the generator 4 are measured by a sensor 19, an exciter 6 is controlled to be operated by a microcomputer 21 thereby to maintain the measured frequency and voltage or the measured reactive power and effective power within a set range, and power responsive to utilization is supplied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winding type having a heat generator and an exciting current control means for controlling an exciting current so that output power having a desired frequency and voltage can be obtained for use in a cogeneration system or the like. The present invention relates to a power generation system configured to interlock with an induction generator to extract heat and generate power at the same time.

[0002]

2. Description of the Related Art In a cogeneration system that generates heat and electric power at the same time, conventionally, in order to effectively use a prime mover, both a refrigerator and a generator as heat generators are linked to the prime mover to drive the same so that cold water is generated. There was a thing which supplies electric power and simultaneously. In some cases, an induction generator is used as the generator, and the refrigerator is driven by the induction generator by diverting the induction generator when the prime mover is stopped.

On the other hand, as for the output control of the refrigerator, as disclosed in, for example, Japanese Patent Laid-Open No. 63-58067, a significant energy saving is achieved not only by the vane throttle and the bypass control but also by the rotation speed control. It is known that it can be achieved.

Further, a wound-rotor induction generator having a cycloconverter for controlling an exciting current, which is used in a pumped-storage power plant, utilizes an optional cycloconverter on a rotor of the wound-rotor induction generator. A rotating magnetic field of speed and strength is formed, and the excitation current is controlled so that the output power of the desired frequency and voltage can be taken out. Even if the rotation speed changes, power is always generated at the specified commercial frequency of 60Hz (or 50Hz). It is known that the motor can be operated at a commercial frequency of 60 Hz even if the rotation speed is changed for load adjustment. This is because in both the wound-rotor induction generator and the synchronous generator, the amount of generated power and the voltage are determined by the strength of the magnetic field and the magnetic positional relationship (that is, the phase) between the rotor side and the stator side. This is because by controlling them, it is possible to generate power at an arbitrary frequency regardless of the rotation speed of the rotor itself.

[0005]

However, in the conventional example, since the synchronous generator or the squirrel-cage induction generator is used as the generator, if the rotational speed of the prime mover is changed to control the output of the refrigerator, Since the output frequency of a synchronous generator changes according to the number of revolutions, it cannot be connected to a commercial power source, and for example, a commercial frequency of 60
There was a drawback that the generated power could not be supplied to the equipment used at Hz. Further, in the case of a normal induction generator, there is a drawback that power generation itself cannot be performed when the rotation speed decreases.

The present invention has been made in view of such circumstances, and the power generation system according to the first aspect of the present invention operates the heat generator at a variable speed to save energy while depending on the application. The power generation system according to the second aspect of the present invention is intended to supply cold power by using exhaust heat from the prime mover, and is used in the middle of spring or autumn. The purpose of the present invention is to make it possible to further improve the energy saving effect when the demand for cold heat and heat is extremely low during the period.

[0007]

In order to achieve the above-mentioned object, a power generation system of the invention according to claim 1 has a single prime mover, a heat generator, and an output power of a desired frequency and voltage. In a power generation system configured to perform heat extraction and power generation at the same time by interlocking with a wound-rotor induction generator having an excitation current control means for controlling the excitation current so as to extract heat, the heat extracted from the heat generator is A temperature sensor for measuring the temperature of the motor is provided, and rotation speed control means for controlling the rotation speed of the prime mover is provided so that the temperature of heat measured by the temperature sensor is maintained within a set range. A sensor for measuring the frequency / voltage or reactive power / active power output from the generator is installed, and the frequency / voltage or reactive power measured by this sensor is also provided. Active power is constituted by providing the output voltage control means for actuating the excitation current control means so as to be maintained within the set range.

In order to achieve the above-mentioned object, the power generation system of the invention according to claim 2 has the above-mentioned claim 1.
In the power generation system of the invention according to claim 1, a transmission clutch that interrupts power transmission is provided between the prime mover and either the heat generator or the wound-rotor induction generator, and the heat generator and the wound-rotor induction generator are provided. When the transmission clutch is disengaged, commercial power is supplied to the wire-wound induction generator so that the wire-wound induction generator can be used as an electric motor. A gas engine, a diesel engine, a steam turbine or the like is used as the prime mover. As the heat generator, an absorption refrigerator that obtains cold water or a heat pump that obtains hot water is used.

In the above-mentioned wound-rotor induction generator, as the frequency conversion means included in the excitation current control means for controlling the excitation current so that the output power having a desired frequency and voltage can be taken out, a thyristor or a PWM using a power transistor is used. Control (pulse width control), a cycloconverter, or the like can be used.

[0010]

According to the configuration of the power generation system of the invention according to claim 1, the number of revolutions of the prime mover is controlled so that the temperature is within the set range based on the temperature of the heat taken out from the heat generator, and the heat is generated. The machine can operate according to the load. On the other hand, for example, when heat transfer power is obtained from the wound-type induction generator, control is performed so that the frequency and voltage are within the set range, and when it is connected to a commercial power source,
It is possible to output electric power according to its application, such as controlling the reactive power / active power to fall within the set range.

Further, according to the structure of the power generation system of the invention of claim 2, the power transmission is interrupted by the transmission clutch, and the winding induction generator is driven by the commercial power source without using the prime mover, and the winding induction generation is performed. The heat generator can be driven at the set rotation speed by using the machine as an electric motor and controlling the exciting current by the exciting device.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a power generation system according to the present invention. A single prime mover (gas engine) 1 is interlocked with a refrigerator 3 as a heat generator via a transmission clutch 2. In addition to being connected, the refrigerator 3 and the wire wound induction generator 4 are interlockingly connected via a transmission shaft 5.

The wound-rotor induction generator 4 is provided with an exciting device 6 for controlling an exciting current so that output power having a desired frequency and voltage can be taken out. Wirewound induction generator 4
An air-conditioning load 8 such as a heat transfer power such as a pump is connected to an output line 7 for extracting electric power from the commercial power supply 10 via a connector 9 in the middle of the load.

A cold water take-out pipe 11 from the refrigerator 3 is provided with a temperature sensor 12 for measuring the temperature of the cold water flowing therethrough, and a calculator 13 is connected to the temperature sensor 12 and based on the measured temperature, The target rotational speed of the prime mover 1 required to obtain the set temperature and the target exciting current controlled by the exciter 6 are calculated. On the other hand, the rotating shaft 1a of the prime mover 1 is provided with a tachometer 14 for measuring its rotational speed, and the target rotational speed from the arithmetic unit 13 and the actual rotational speed measured by the tachometer 14 are input to the comparator 15. Then, an open signal or a close signal is output to the drive circuit 16 based on the comparison between the two, and the fuel supply pipe 1 to the prime mover 1
7 automatically adjusts the throttle 18 provided to adjust the amount of fuel supplied to the prime mover 1, and rotates the prime mover 1 so that the temperature of heat measured by the temperature sensor 12 is maintained within a set range. The rotation speed control means is configured to control the speed.

The output line 7 is provided with a sensor 19 for measuring the frequency / voltage or the reactive power / active power output from the wound-rotor induction generator 4, while the air conditioning load 8 is equipped with a sensor 19 for measuring the set air conditioning temperature, for example. Load sensor 20 for detecting load
Is provided, the sensor 19 and the load sensor 20 are connected to a microcomputer 21 as output voltage control means, and the microcomputer 21 and the exciter 6 are connected.
A target frequency / voltage corresponding to the load of the air conditioning load 8 is calculated, the target frequency / voltage is compared with the frequency / voltage measured by the sensor 19, and a control signal is sent to the exciter 6 based on the comparison result. Is output, and the frequency / voltage measured by the sensor 19 is maintained within a set range.

When the output power from the wound-rotor induction generator 4 is grid-connected to the commercial power supply 10, the target reactive power / active power is set in advance in the microcomputer 21, while the sensor 19 winds it. The actual reactive power / active power output from the linear induction generator 4 is measured, the target reactive power / active power is compared with the actual reactive power / active power, and the excitation device 6 is controlled based on the comparison result. It is configured to output a signal and operate the exciter 6 such that the actual reactive power / active power measured by the sensor 19 is maintained within a set range.

With the above-mentioned structure, while controlling the rotation speed of the prime mover 1 to operate the refrigerator 3 at a variable speed to save energy, the exciter 6 is operated and controlled so that the electric power or the commercial power corresponding to the air conditioning load 8 is supplied. It is possible to take out desired power such as power that is grid-connected to the power supply 10.

When power transmission is cut off by the transmission clutch 2, commercial power is supplied to drive the wound-rotor induction generator 4, and the refrigerator 3 is driven using the wound-rotor induction generator 4 as an electric motor. It is possible to output a control signal from the calculator 13 to the exciter 6 to control the exciting current by the exciter 26 and operate the refrigerator 3 at a variable speed to obtain the required cold water. If there is a heat demand at this time, for example, a gas-fired boiler may obtain a required amount of heat.

In the above embodiment, the wound-rotor induction generator 5
The control of (1) actually requires the concept and system configuration of so-called vector control in which the magnetic flux direction component and the torque component are separated, but it is omitted in this system configuration because it is an established technique. Further, when the system is connected to the commercial power source, the power generation control is switched from the frequency / voltage control to the reactive power / active power control, but this is a common matter and is omitted.

In the above embodiment, the refrigerator 3 is operatively connected to the prime mover 1 via the transmission clutch 2. However, in the present invention, instead of the refrigerator 3, a heat generator such as a heat pump for obtaining hot water is interlocked. You may make it connect.

In the above embodiment, the wound-type induction generator 4 is used.
And the prime mover 1 may be interlockingly connected via the transmission clutch 2, and the refrigerator 3 and the wire wound induction generator 4 may be interlockingly connected via the transmission shaft 5.

The prime mover is not limited to the gas engine 1 as in the above-mentioned embodiment, but a steam turbine, a gas turbine or the like can be used.

[0024]

As is apparent from the above description, according to the power generation system of the first aspect of the present invention, the heat generator can be efficiently operated at a variable speed according to its load, so that energy saving can be achieved. In addition, by controlling the exciting current of the exciter, the wound-type induction generator can output power according to the application regardless of the rotation speed control of the prime mover, and variable voltage variable frequency power is required. As the load to be set, for example, when a centrifugal rotating machine for air conditioning heat transfer is selected and the air conditioning load is small, the rotation speed is reduced according to the air conditioning load so that the driving power is almost the cube of the rotation speed. Since it can be reduced in proportion to, a significant energy saving effect can be achieved as compared with the case where it is used at a constant rotation speed. Further, when the exciting current of the exciter is controlled to output constant voltage and constant frequency power, it can be connected to a commercial power source, which is extremely useful.

According to the power generation system of the second aspect of the invention, when cold water or hot water is obtained by utilizing the exhaust heat from the prime mover, the cold or hot demand is generated in an intermediate period such as spring or autumn. When the power is extremely small, the power transmission is cut off by the transmission clutch, the wire wound induction generator is driven by a commercial power source without using the prime mover, the wire wound induction generator is used as an electric motor, and the exciting current is controlled by the exciter. Since the cold water or the hot water can be obtained by driving the heat generator at the set number of revolutions, it is possible to eliminate the waste of driving the prime mover due to the extremely small demand for the cold heat or the hot heat, and to further improve the energy saving effect. In particular, an exhaust heat refrigerator has a low coefficient of performance, and by using a refrigerator as a heat generator to obtain cold heat, a large amount of energy can be saved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a power generation system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Prime mover 2 ... Transmission clutch 3 ... Refrigerator as a heat generator 4 ... Wound type induction generator 6 ... Excitation device 10 ... Commercial power supply 12 ... Temperature sensor 19 ... Sensor 21 ... Microcomputer as output power control means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kosuke Nakatani 4-1-2, Hirano-cho, Chuo-ku, Osaka City Osaka Gas Co., Ltd.

Claims (2)

[Claims] 1. A heat generator and a winding-type induction generator having an exciting current control means for controlling an exciting current so as to extract output power having a desired frequency and voltage, are linked to one prime mover. A power generation system configured to simultaneously perform heat extraction and power generation, wherein a temperature sensor for measuring the temperature of heat extracted from the heat generator is provided, and the temperature of heat measured by the temperature sensor is set. A rotation speed control unit for controlling the rotation speed of the prime mover so as to be maintained within the range is provided, and
A sensor for measuring the frequency / voltage or reactive power / active power output from the wire wound induction generator is provided, and the frequency / voltage or reactive power / active power measured by the sensor is maintained within a set range. Thus, the power generation system is provided with output voltage control means for operating the excitation current control means. 2. The power generation system according to claim 1, further comprising a transmission clutch for interrupting power transmission between the prime mover and either the heat generator or the wound-rotor induction generator, and the heat generation. Machine and the wire wound induction generator are interlocked and connected, and in the disengaged state of the transmission clutch, commercial power is supplied to the wire wound induction generator so that the wire wound induction generator can be used as an electric motor. There is a power generation system.