JPS6363751B2 - - Google Patents

Abstract

PURPOSE:To stabilize operation by detecting the velocity of an energy source and the number of revolution of a generator and controlling the output of said generator in accordance with the smaller one of the detected output control signal. CONSTITUTION:A first output control signal generator 8 generates an output control signal A corresponding to a wind velocity on receiving a signal from a wind velocity detecting device 9, while a second output control signal generator 10 generates an output control signal B corresponding to the number of revolution of a generator. Both of the signals A, B are compared by a comparing amplifier 11, and the smaller signal of the two is outputted and given to an outer control unit 6, to control the output of a generator 2. Thereby, a stable operation can be carried out from an unstable energy source.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to an improvement in a power generation device using an unstable energy source such as wind or running water.

[Conventional technology]

BACKGROUND ART Conventionally, for example, in a wind turbine power generation device that uses wind as an energy source, there has been a method of detecting wind speed and generating an output signal proportional to the cube of the wind speed, thereby controlling the output of the generator.

FIG. 3 shows a schematic configuration of a control device based on such a system. In this figure, 1 is a drive unit such as a windmill, 2 is a generator coupled to the windmill, 3 is a finger speed generator coupled to the generator,
This is for detecting the rotation speed of the generator. 4 is an electric motor for starting the generator; 5
1 is a control device for the electric motor, which controls the electric motor 4 based on a signal from the finger speed generator 3 and a signal from a wind speed detector, which will be described later. 6 is an output control device for controlling the output of the generator 2, 7 is a load, and 8 is an output control signal generator for controlling the output control device 6, which adjusts the wind speed based on a signal from a wind speed detector to be described later. A signal corresponding to the control signal is generated as a control signal. A wind speed detection device 9 generates a signal proportional to the cube of the detected wind speed and supplies it to the motor control device 5 and the output control signal generator 8.

By the way, in wind turbine generators that do not have self-starting ability, a starting device is essential to start power generation, that is, rotation, and it is possible to use wind speed as a reference signal for checking start-up conditions and controlling output during operation. It was being done. That is, the motor control device 5 confirms that the wind speed is operable based on the output signal from the wind speed detection device 9, and confirms that the generator 2 is in a stopped state based on the signal from the finger speed generator 3. As a result, a starting command is issued from the motor control device 5 to start the electric motor 4. As a result, the wind turbine 1 and the generator 2 are connected coaxially with the electric motor 4.
is rotated as a load, and the rotation speed gradually increases.
The motor control device checks the rotational speed at this time based on a signal from the finger speed generator 3. When it is confirmed through this check that the rotation speed of the wind turbine 1 has reached a speed at which continuous operation is possible, the power supply to the electric motor 4 is stopped. On the other hand, the output control signal generator 8 generates a control signal corresponding to the wind speed at that time based on the signal from the wind speed detection device 9, and thereby controls the output control device 6 in accordance with the wind speed. Generator output is supplied to load 7.

[Problem that the invention seeks to solve]

A conventional wind turbine generator is configured as described above, and when the generator reaches a predetermined rotation speed, power supply to the electric motor is stopped, and the shaft power for driving the generator is limited to the wind energy generated by the wind turbine. At this time, if the wind speed increases, the output control device 6 performs output control commensurate with the wind speed, so the wind turbine 1 becomes overloaded and decelerates, eventually coming to a stop. When the stoppage is confirmed, a start command is issued to the electric motor 4 to restart it as described above. Thereafter, the engine starts and stops repeatedly, causing so-called hunting. Hunting not only prevents normal operation but also has a negative effect on the electric motor, wind turbine shaft, etc. Additionally, when the wind speed changes irregularly, problems such as stalling due to overload occur even during operation.

These problems are due to the use of wind speed as a reference signal for control, so
One possible way to eliminate this problem is to use the actual rotation speed of the wind turbine or generator as a reference signal for control, but since the rotation speed is controlled by the output amount, that is, the load amount, and the wind energy, the same wind speed Even in this case, it is difficult to perform good control because increasing the output amount causes the rotational speed to decrease, and if the rotational speed decreases, decreasing the output amount causes the rotational speed to increase.

The present invention was made to solve these problems, and provides a power generation device that can operate stably even with irregular and unstable energy.

[Means for solving problems]

This invention comprises: a first control signal generator that generates an output control signal that corresponds to the speed of an energy source; a second control signal generator that generates an output control signal that corresponds to the rotational speed of a generator; An output control device is provided which compares the output signals of both control signal generators and controls the generator output in response to the smaller output signal.

[Effect]

At startup, even if there is a constant wind speed, the rotational speed of the generator increases from 0, so output control is performed in accordance with the rotational speed. As the rotational speed increases and reaches a point corresponding to the current wind speed, power control is applied to the wind speed. After that, output control is controlled by the wind speed signal, but if the wind speed suddenly increases and the rotation speed does not increase, the output control is performed by the rotation speed signal, and after the rotation speed increases, the output control is controlled by the wind speed signal. Shift to output control. On the other hand, when the wind speed decreases, the output is reduced by the wind speed signal before the rotational speed decreases, allowing stable operation.

〔Example〕

An embodiment of the present invention shown in FIG. 1 will be described below.

In this figure, 8 is a first output control signal generator that receives a signal from a wind speed detection control 9 and generates an output control signal A according to the wind speed, as in the conventional device, and 10 is a finger speed generator 3. A second output control signal generator is coupled to generate an output control signal B according to the rotation speed of the generator, and 11 is a comparison unit that compares the signals A and B and selects and outputs the smaller signal. The amplifier supplies this output to the output control device 6, thereby controlling the output of the generator 2 in accordance with the smaller of the signals A and B, and supplies the output to the load 7.

The rest of the configuration is the same as the conventional one, so the explanation will be omitted. Note that FIG. 2 is a diagram showing the relationship between wind speed, rotation speed, and output. Curve C shows the relationship with the output corresponding to wind speed as a reference, and curve D shows a certain increase in the rotational speed of the wind turbine when output corresponding to wind speed is taken as reference. .

Operation of the embodiment shown in FIG. 1 begins in the same manner as the conventional apparatus described above. The mode of control is as described in the [Operation] column. Although the above description has been made regarding a wind turbine generator, the present invention is not limited to this, and can be applied to various power generation devices in which the energy source changes unstablely, such as hydroelectric power generation in small rivers. .

〔Effect of the invention〕

Since the present invention is configured as described above, it is possible to start the power generation device in a good manner and to continue stable operation.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 2 is a characteristic diagram showing the relationship between the output control signal and the output in the above embodiment, and FIG. 3 is a schematic configuration diagram showing a conventional device. be. In the figure, 1 is a windmill, 2 is a generator, 3 is a finger speed generator,
4 is a motor, 5 is a motor control device, 6 is an output control device, 7 is a load, 8 is a first output control signal generator, 9 is a wind speed detection device, 10 is a second output control signal generator, 11 is a It is a comparison amplifier. Note that the same symbols indicate corresponding parts.

Claims (1)

[Claims] 1. A device having a drive section driven by an energy source such as wind or running water, and a generator coupled to this drive section, in which the speed of the energy source is detected, and the speed of the energy source is detected. a first output control signal generator that generates an output control signal for the generator according to the rotation speed of the generator; and a first output control signal generator that detects the rotation speed of the generator and generates an output control signal for the generator according to the rotation speed. An unstable output control device comprising: a second output control signal generator; and an output control device that compares the output signals of the two output control signal generators and controls the output of the generator in response to the smaller output signal. A power generation device using an energy source. 2. A power generation device using an unstable energy source according to claim 1, wherein the energy source is wind and the drive unit is a windmill.