JP5482217B2 - Flywheel emergency stop device and flywheel power storage device - Google Patents

Description

  The present invention relates to a flywheel emergency stop device that makes an emergency stop of a rotating flywheel, and a flywheel power storage device including the device.

  The flywheel power storage device includes a flywheel provided in a rotor, a motor / generator attached to the rotor, a bearing portion that supports the rotor, and a container that accommodates these, and the flywheel transfers power energy to the flywheel. It stores electricity by converting it into rotational energy. In the flywheel power storage device, it is necessary to reduce the air resistance and the friction of the bearing portion that inhibit the rotation of the flywheel and the motor / generator during power storage as much as possible. For this reason, the inside of the container for housing the motor / generator and the flywheel is evacuated, and a magnetic bearing or the like is adopted as a bearing portion for supporting the rotor.

The flywheel power storage device having the above configuration needs to stop the flywheel urgently in order to ensure safety when an abnormality such as an earthquake occurs. Examples of conventional methods for stopping the flywheel include the methods shown in the following (1) to (3).
(1) Method of stopping by a braking mechanism using a permanent magnet (2) Method of injecting liquid such as water into a container and stopping by resistance of water (3) Control device for flywheel power storage device To stop using

  Patent Document 1 below discloses a technique for emergency stop of a flywheel by the method (2). Specifically, flywheels mounted over a plurality of stages of the rotor are accommodated in individual casings, and an inlet for injecting a liquid such as water is provided in the lowermost casing, and the vaporized gas or the temperature rise By adopting a configuration in which the discharge port for discharging the liquid is provided in the uppermost stage, it is possible to urgently stop the flywheel while preventing damage to the device caused by frictional heat.

JP-A-8-247183

  By the way, the method (1) described above is a method in which a magnetic field of a permanent magnet is applied to the flywheel to generate an eddy current, and the flywheel is stopped by a braking torque generated by the eddy current. In this method, since the temperature of the flywheel and the rotor rapidly rises due to the flowing eddy current, it is necessary to efficiently release the generated heat to the outside. However, as described above, the bearing portion needs to reduce friction as much as possible. When a magnetic bearing or the like is adopted for the bearing portion, the rotor and the bearing are not in contact with each other, so that heat can be efficiently released. There is a problem that can not be done.

  Further, in the method (2) described above, since the liquid is directly supplied to the flywheel, when the weight of the flywheel is small, the resistance of the liquid becomes too large and mechanical stress increases. This may cause the flywheel power storage device to be destroyed. Further, in the method (3) described above, since the flywheel is stopped by consuming the stored electric power by the control device, the time required for the stop is inevitably increased, and the flywheel is urgently stopped. It is difficult.

  The present invention has been made in view of the above circumstances, and provides a flywheel emergency stop device capable of safely stopping an emergency stop of a flywheel without giving mechanical stress, and a flywheel power storage device including the device. The purpose is to provide.

In order to solve the above-mentioned problem, a flywheel emergency stop device according to the present invention is a flywheel emergency stop device (4) for emergency stop of a flywheel (1a) included in a flywheel power storage device (1), wherein the flywheel The power consuming liquid tank (4a) that houses the liquid load (W) that consumes the electric power stored in the wheel power storage device, and the supply destination of the power stored in the flywheel power storage device is the power consuming liquid tank. A switching unit (4b) that switches to any one of the liquid load and the system load, and when the flywheel is brought to an emergency stop, the flywheel power storage device is controlled to output the stored power and the switching A control unit (4c) that controls the unit to switch the supply destination of power from the flywheel power storage device to the liquid load in the liquid tank for power consumption. It is characterized in that to obtain.
Further, in the flywheel emergency stop device of the present invention, a pipe (4d) for supplying the liquid load to the liquid tank for power consumption is led to the liquid tank for power consumption, When an emergency stop of the flywheel is performed, control is performed to supply the liquid load to the liquid tank for power consumption by opening a valve (4e) provided in the pipe.
In the flywheel emergency stop device of the present invention, the power consumption liquid tank is supplied with power from the flywheel power storage device (11a, 11b), and the power consumption liquid tank A sensor (12) for detecting the liquid level of the liquid load is provided, and the control unit controls opening / closing of a valve provided in the pipe based on a detection result of the sensor.
The flywheel emergency stop device of the present invention is characterized in that the liquid load is a refrigerant used for cooling the flywheel power storage device.
The flywheel power storage device according to any one of the above, wherein in the flywheel power storage device (1) that stores power by converting electric power energy into rotational energy of the flywheel (1a), the flywheel is urgently stopped. A flywheel emergency stop device is provided.

  According to the present invention, when an emergency stop of the flywheel is performed, the flywheel power storage device is controlled to output the stored power, and the power supply destination from the flywheel power storage device is set in the power consuming liquid tank. The flywheel is urgently stopped by switching to the liquid load and controlling the flywheel power storage device so that the stored power is consumed by the liquid load. For this reason, there is an effect that the flywheel can be urgently stopped safely without applying mechanical stress.

It is a figure which shows the outline | summary of the external appearance of the flywheel electrical storage apparatus by one Embodiment of this invention. It is a figure which shows in more detail the structure of the flywheel emergency stop apparatus and flywheel electrical storage apparatus by one Embodiment of this invention.

  Hereinafter, a flywheel emergency stop device and a flywheel power storage device according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an outline of the appearance of a flywheel power storage device according to an embodiment of the present invention. As shown in FIG. 1, the flywheel power storage device 1 includes a flywheel, a motor / motor in a flywheel chamber 2 having a cylindrical body 2a and a hemispherical head 2b provided on the body 2a. It is a configuration that houses various internal mechanisms such as a generator, and stores electric power supplied from outside by converting it into rotational energy of the flywheel. The details of the flywheel, motor / generator and the like housed in the flywheel chamber 2 will be described later.

  The flywheel power storage device 1 includes a cooling device 3 that cools the flywheel power storage device 1 in order to prevent a temperature increase due to heat generated inside. The cooling device 3 includes a cooling water tank 3a, a pump 3b, a cooling water pipe 3c, and a valve 3d. The cooling water tank 3 a is a tank that stores cooling water (refrigerant) for cooling the flywheel power storage device 1 while cooling it. The cooling water tank 3a can store several hundred liters of cooling water. The pump 3b sucks the cooling water stored in the cooling water tank 3a, and pressurizes and sends out the cooling water toward the cooling water pipe 3c in order to circulate through the cooling water pipe 3c.

  The cooling water pipe 3c is a pipe spirally attached to the side surface of the body portion 2a of the flywheel chamber 2, and circulates the cooling water pressurized by the pump 3b around the side surface of the body portion 2a. . As the cooling water circulates through the side surface of the body portion 2a, the heat stored in the body portion 2a is absorbed by the cooling water, whereby the flywheel power storage device 1 is cooled. The cooling water via the cooling water pipe 3c is collected in the cooling water tank 3a. The valve 3d is provided between the pump 3b and the cooling water pipe 3c, and opens or closes the flow path between the pump 3b and the cooling water pipe 3c by being in an open state or a closed state.

  The flywheel power storage device 1 includes a flywheel emergency stop device 4 that stops the flywheel in an emergency when an abnormality such as an earthquake occurs. The flywheel emergency stop device 4 includes a storage tank 4a (a liquid tank for power consumption) that stores the cooling water used in the cooling device 3. When the flywheel is stopped in an emergency, the cooling water is stored in the storage tank 4a. The power stored in the flywheel power storage device 1 is supplied to the cooling water W (liquid load) stored in the storage tank 4a and consumed.

  FIG. 2 is a diagram showing in more detail the configuration of the flywheel emergency stop device and the flywheel power storage device according to an embodiment of the present invention. As shown in FIG. 2, the flywheel emergency stop device 4 includes a storage tank 4a (liquid tank for power consumption), a load switching relay 4b (switching unit), a controller 4c (control unit), a pipe 4d, and a valve 4e (valve). The flywheel included in the flywheel power storage device 1 is urgently stopped. The time required for emergency stop of the flywheel depends on the capacity of the flywheel power storage device 1 and the resistance of the cooling water W stored in the storage tank 4a, but is, for example, about several seconds to several tens of seconds. .

  As described above, the storage tank 4a is a tank used for storing the cooling water used in the cooling device 3 and consuming the electric power stored in the flywheel power storage device 1, for example, about 200 liters of cooling water. It can be accommodated. Since the storage tank 4a is used for consuming the electric power stored in the flywheel power storage device 1, it is desirable that the storage tank 4a be formed of an insulating material (for example, ceramic).

  In the storage tank 4a, a pair of electrodes 11a and 11b to which power from the flywheel power storage device 1 (R-phase and S-phase power in the example shown in FIG. 2) is supplied, and cooling in the storage tank 4a. A sensor 12 for detecting the liquid level of the water W is provided. The electrodes 11a and 11b are arranged apart from each other by a distance that takes into account the magnitude of the resistance of the cooling water W required to consume the electric power stored in the flywheel power storage device 1, and the electrodes 11a and 11b It is arranged at a position separated from the inner wall by a distance that can ensure insulation.

  The sensor 12 detects whether or not the liquid level of the cooling water W stored in the storage tank 4a is above a predetermined position set in advance. Here, the liquid level of the cooling water W detected by the sensor 12 needs to be higher than at least the lower ends of the electrodes 11a and 11b. This is because at least a part of the electrodes 11a and 11b needs to be immersed in the cooling water W in order to consume the electric power stored in the flywheel power storage device 1 using the cooling water W as a liquid load. . The liquid level of the cooling water W detected by the sensor 12 can be set at an arbitrary position as long as it is at least a position above the lower ends of the electrodes 11a and 11b.

  In addition, one end of the storage tank 4a is connected to a pipe between the pump 3b and the valve 3d included in the cooling device 3, and the cooling water used in the cooling device 3 is supplied into the storage tank 4a from the other end. The pipe 4d is led. The pipe 4d is provided with a valve 3d that opens or closes the flow path of the pipe 4d when the pipe 4d is opened or closed.

  The load switching relay 4b is configured such that, under the control of the controller 4c, the connection destination of the inverter 1c included in the flywheel power storage device 1 is set to the R phase and S phase of the system load, or the electrodes provided in the storage tank 4a Switch between 11a and 11b. The inverter 1c included in the flywheel power storage device 1 is connected to the R phase and S phase of the system load during normal operation, and is switched to connection to the electrodes 11a and 11b under the control of the controller 4c during an emergency stop.

  The controller 4c performs various controls when the flywheel included in the flywheel power storage device 1 is urgently stopped. Specifically, the controller 4c outputs a control signal C0 to the inverter 1c included in the flywheel power storage device 1 and performs control (regeneration control) to output the power stored in the flywheel power storage device 1. Moreover, the control signal C1 is output with respect to the load switching relay 4b, and the control which switches the connection destination of the inverter 1c with which the flywheel electrical storage apparatus 1 is provided to electrode 11a, 11b is performed.

  Further, control signals C2 and C3 are output to perform opening / closing control of the valves 3d and 4e provided in the cooling device 3 and drive control of the pump 3b provided in the cooling device 3. Here, the controller 4c performs opening / closing control of the valve 4e based on the detection result of the sensor 12 provided in the storage tank 4a when the flywheel is stopped urgently. This is because the liquid level of the cooling water W in the storage tank 4a is set at a predetermined position.

  Here, as shown in FIG. 2, the flywheel power storage device 1 includes a flywheel 1a, a motor / generator 1b, and an inverter 1c in a flywheel chamber 2, and is used as a secondary power source for a system load. The That is, power is supplied from the main power supply (not shown) to the system load in the figure, but the flywheel power storage device 1 supplies power to the system load when, for example, power from the main power supply is insufficient. The output of the flywheel power storage device 1 is, for example, about 200 kW to several GW.

  The flywheel 1a is a disk that is guided and rotated concentrically with the motor / generator 1b. The flywheel 1a is rotated by the rotational drive of the motor / generator 1b, and continues to rotate by inertia even when the rotational drive by the motor / generator 1b is stopped. The motor / generator 1b rotationally drives the flywheel 1a as a motor by AC drive power supplied from the inverter 1c. Moreover, it functions as a generator which converts rotational energy into electric energy by decelerating the rotational speed of the flywheel 1a rotated by inertia. The flywheel chamber 2 that houses the flywheel 1a and the motor / generator 1b is evacuated to reduce the air resistance that hinders these operations.

  The inverter 1c converts AC power supplied to a system load from a main power supply (not shown) into AC power having a voltage suitable for driving the motor / generator 1b, and the motor / generator 1b is converted into a motor by the converted AC power. Drive as. Further, the AC power supplied from the motor / generator 1b is converted into AC power having a voltage equal to the voltage of the system load and output to the load switching relay 4b.

  Next, the operation when the flywheel 1a included in the flywheel power storage device 1 is urgently stopped will be described. First, during normal operation, the inverter 1c of the flywheel power storage device 1 is connected to the system load by the load switching relay 4b, and AC power supplied from the main power supply (not shown) to the system load is stored in the flywheel power storage device 1. Has been. Further, the valve 3d of the cooling device 3d is opened, and the valve 4e of the flywheel emergency stop device 4 is closed, and the cooling water is circulated around the side surface of the trunk portion 2a by driving the pump 3b. The storage tank 4a is empty without being supplied with the cooling water W therein.

  Next, when the flywheel 1a is urgently stopped, a control signal C0 is output from the controller 4c to the inverter 1c, and a control signal C1 is output from the controller 4c to the load switching relay 4b. In addition, a control signal C2 is output from the controller 4c to the valve 4e.

  When the control signal C0 is output from the controller 4c to the inverter 1c, regenerative control is performed. With this control, the motor / generator 1b functions as a generator, and the rotational energy of the flywheel 1a is converted into electric energy by driving the motor / generator 1b by the flywheel 1a that rotates by inertia. Is output from the inverter 1c. Further, when the control signal C1 is output from the controller 4c to the load switching relay 4b, the connection destination of the inverter 1c included in the flywheel power storage device 1 is switched to the electrodes 11a and 11b. Thereby, the alternating current power output from the inverter 1c of the flywheel power storage device 1 is supplied to the electrodes 11a and 11b.

  When the control signal C2 is output from the controller 4c to the valve 4e, the valve 4e is opened. Then, the cooling water pressurized by the pump 3b of the cooling device 3 is supplied into the storage tank 4a via the pipe 4d. The controller 4c controls the opening and closing of the valve 4e based on the detection result of the sensor 12. When the liquid level of the cooling water W stored in the storage tank 4a reaches a predetermined position, the controller 4c. The valve 4e is closed by this control.

  By the above control, the electrodes 11a and 11b provided in the storage tank 4a are immersed in the cooling water W stored in the storage tank 4a. Then, an alternating current flows between the electrodes 11a and 11b, and thereby electric power is consumed by the resistance R (liquid resistance) of the cooling water W existing between the electrodes 11a and 11b. In this way, the power stored in the flywheel power storage device 1 is efficiently consumed, and as a result, the flywheel 1a can be urgently stopped.

  Here, although the temperature of the cooling water W rises by consuming electric power by the cooling water W, the temperature of the cooling water W may exceed 100 ° C. as long as the cooling water W exists as a liquid in the storage tank 4a. Absent. For this reason, it is possible to safely consume large power. Moreover, in this embodiment, since the electric power stored in the flywheel power storage device 1 is only consumed by the cooling water W stored in the storage tank 4a, the flywheel can be safely operated without applying mechanical stress. 1a can be stopped.

  The flywheel emergency stop device and the flywheel power storage device according to one embodiment of the present invention have been described above, but the present invention is not limited to the above embodiment, and can be freely changed within the scope of the present invention. For example, in the above embodiment, the cooling water used in the cooling device 3 that cools the flywheel power storage device 1 is stored in the storage tank 4a and used for power consumption. However, the cooling water and power consumption used in the cooling device 3 are used. It may be used separately from the dedicated water used for the.

  Moreover, in the said embodiment, when stopping the flywheel 1a in an emergency, the cooling water W was supplied to the storage tank 4a, However, Water may always be stored in the storage tank 4a. Furthermore, in the above-described embodiment, an example in which water (cooling water) is used as the liquid load used for power consumption has been described. However, liquids other than water may be used. For example, a liquid having a low boiling point comparable to the boiling point of water is desirable because denaturation and electrolysis due to the flow of electricity hardly occur.

DESCRIPTION OF SYMBOLS 1 Flywheel electrical storage apparatus 1a Flywheel 4 Flywheel emergency stop apparatus 4a Storage tank 4b Load switching relay 4c Controller 4d Piping 4e Valve 11a, 11b Electrode 12 Sensor W Cooling water

Claims (4)

A flywheel emergency stop device for emergency stop of a flywheel included in a flywheel power storage device,
A liquid tank for power consumption that houses a liquid load that consumes the power stored in the flywheel power storage device;
A switching unit that switches a supply destination of the power stored in the flywheel power storage device to either the liquid load or the system load in the liquid tank for power consumption;
When the flywheel is urgently stopped, the flywheel power storage device is controlled to output the stored power, and the switching unit is controlled to supply power from the flywheel power storage device to the power consumption. A control unit for switching to the liquid load in the liquid tank ,
A pipe for supplying the liquid load to the liquid tank for power consumption is led to the liquid tank for power consumption,
The said control part performs control which supplies the said liquid load to the said liquid tank for electric power consumption by opening the valve provided in the said piping, when stopping the said flywheel urgently
A flywheel emergency stop device characterized by that . The liquid tank for power consumption is provided with an electrode to which power from the flywheel power storage device is supplied, and a sensor for detecting the liquid level of the liquid load in the liquid tank for power consumption,
The flywheel emergency stop device according to claim 1 , wherein the control unit controls opening and closing of a valve provided in the pipe based on a detection result of the sensor. The flywheel emergency stop device according to claim 1 or 2 , wherein the liquid load is a refrigerant used for cooling the flywheel power storage device. In a flywheel power storage device that stores power by converting electric power energy into rotational energy of a flywheel,
The flywheel electrical storage apparatus provided with the flywheel emergency stop apparatus as described in any one of Claims 1-3 which carries out the emergency stop of the said flywheel.

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