KR20160009983A - Energy storage system of container type using wind generator - Google Patents

Abstract

The present invention relates to a container type energy storage device for a wind power generator, capable of promoting stable power supply to the system of a wind power generator by connecting a large energy storage device to the system, and performing optimal air conditioning by adding a thermo-hygrostat. The container type energy storage device includes: a generator for generating electric energy by using rotational force delivered through a power delivery device delivering rotational energy from a blade to the rear end; a power converting device converting the electric energy, generated by the generator, into suitable energy for the supply of the system; and an energy storage device charging the power, converted by the power converting device, and supplying the charged power to the system when power supplied to the system is not higher than a predetermined level. The energy storage device includes: a bidirectional power control device controlling the charging of the electric energy, converted by the power converting device, and supplying the power to the system by controlling the discharging of the charged power when supply power of the system is not higher than a predetermined level; and a battery energy storage device charging and discharging the electric energy.

Description

[0001] The present invention relates to a container type energy storage device for a wind turbine generator,

The present invention relates to a container type energy storage system (ESS) for a wind power generator, and more particularly, to a system for stabilizing power supply by connecting a mass energy storage device to a system of a wind power generator, To a container type energy storage device for a wind turbine generator that can perform an optimum air conditioning function.

Demand for renewable energy is steadily increasing due to measures such as depletion of fossil fuels and global warming. Among them, the installed capacity of wind power generation is increasing rapidly worldwide, .

Wind power generation is a method of converting wind (wind power) into electric power using a wind turbine. In recent years, the share of wind power generation in the total power generation has been increasing. Especially, the electricity produced through wind power generation can be sold through the power exchange.

However, since wind power generation utilizes wind power, various conditions for wind power generation such as wind speed change are variable, so that the amount of power generated by the wind power generation is not constant, which makes it difficult to sell the power. Therefore, a method of controlling the energy storage device (BESS: Battery Energy Storage System) in order to control the output change of the wind power generation has been proposed.

Wind power systems that link energy storage devices can be applied to a system where only part of the generated energy is sent to the grid without stopping the wind power generator and the rest is stored in the energy storage device (BESS). However, It is necessary to increase the capacity of the energy storage device (BESS). Therefore, there are cost and technical limitations.

On the other hand, the current controller gain value due to the inductance conversion of the wind turbine before and after the grid connection plays an important role in the stable system input in the wind power generator using the 850kW double fed induction generation (DFIG). A wind turbine using a dual power generation system controls the stator voltage by controlling the rotor current, and the controlled stator voltage is linked to the system.

A prior art for a power system in which wind power generation and energy storage devices are connected is disclosed in the following Patent Document 1: Korean Patent Laid-Open Publication No. 10-2011-0078965 (published on July 7, 2011).

In the prior art disclosed in Patent Document 1, in the state where the wind power generator 100 and the power storage unit 130 are linked, the central control unit 140 controls the wind power generator 100 connected to the power storage unit 130 It is judged whether it is connected with the system. In the grid-connected case, the operation mode for controlling the charging and discharging states of the power storage unit 130 is selected according to a constant control point. Then, the central control unit 140 calculates the wind power generation amount of the wind power generator 100 and the power generation amount by the load time period. Then, the charging and discharging control method of the power storage unit 130 is determined according to the grid condition and the electricity sales price condition for each load time period. And controls the operation of the entire power system by controlling the charge / discharge state of the power storage unit 130 according to the determined control method.

Such prior art has advantages of securing the optimization and stability of power supply by predicting the demand power of the wind power generation output and the system, and supplying the power obtained from the wind power generation costly, thereby maximizing the profitability of the stable operation of the system and the profit of the operator.

Korean Patent Publication No. 10-2011-0078965 (Published July 7, 2011)

However, the above-described related art has a disadvantage in that power can not be efficiently operated because a power conversion unit and a power storage unit are separately provided.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problems occurring in the related art as described above and to solve various problems occurring in a power system in which general wind power generation and energy storage devices are connected, A container type energy storage device for a wind turbine generator which is capable of providing a stable power supply to the system and performing an optimum air conditioning function by adding a constant temperature and humidity device therein.

It is another object of the present invention to provide a battery energy storage device and a bidirectional power control device in a single container and to efficiently perform charging and discharging control and power grid connection of the battery energy storage device through a bidirectional power control device And a container type energy storage device for a wind power generator.

It is still another object of the present invention to provide a container type energy storage device for a wind turbine generator which has a cell structure having a parallel structure in the form of a cartridge having a series structure for boosting to provide a battery energy storage device through serial / .

According to an aspect of the present invention, there is provided a container type energy storage device for a wind turbine, including: a blade for obtaining rotational energy by wind; A power transmitting device for transmitting the rotational energy obtained from the blade to the rear end; A generator for generating electrical energy using a rotational force transmitted through the power transmission device; A power converter for converting electric energy produced by the generator into a form suitable for supplying to the system; And an energy storage device for charging the power converted by the power conversion device and supplying the power to the system when the power supplied to the system is less than a predetermined level,

Wherein the energy storage device controls the charging of the electric energy converted by the power conversion device and controls the discharging of the charging power to supply power to the system when the supply power of the system is less than a predetermined level, And a battery energy storage device for charging and discharging electric energy.

Wherein the bidirectional power control device and the battery energy storage device are integrated together in one container.

The energy storage device may further include a thermo-hygrostat to perform the constant-temperature and humidity-dependent air-conditioning according to a temperature inside the container or a temperature of the cell unit in the battery energy storage device.

The energy storage device may further include a fire extinguishing device that extinguishes the fire extinguishing liquid when fire is detected inside the container.

The bidirectional power control apparatus includes a primary protection circuit that detects a current of power supplied to the system from the power conversion apparatus and automatically performs a power shutdown operation when the detected current is an overcurrent; A harmonic filter for removing harmonics included in the AC power supply; A power converter for converting AC power from the harmonic filter to DC power and outputting it as charging energy and converting DC power as discharge energy into AC power; A secondary protection circuit that detects a current supplied from the power conversion unit to the battery energy storage device and automatically performs a power shutdown operation when the current is an overcurrent; And a main central processing unit for controlling the bidirectional power conversion of the power conversion unit, controlling the constant current and the constant voltage charging, and controlling the air conditioning and fire extinguishing apparatus.

The bidirectional power control device includes a monitoring device for measuring power quality (current THD), measuring temperature, and detecting fire; And a can communication unit for acquiring a voltage measurement value and a temperature measurement value of the cell unit acquired by the battery energy storage unit 52 and transmitting the voltage measurement value and the temperature measurement value to the main central processing unit.

The battery energy storage device may include a primary protection circuit that detects a current of the charging power supplied from the bidirectional power control device and performs a power-off operation when the detection current is an overcurrent; A plurality of cartridges each containing a plurality of cell units for storing the charging power and discharging stored power; A main board for detecting a power state of the cartridge and controlling charging and discharging according to the detected power state; A liquid crystal display for visually displaying an energy charging state of the battery energy storage device under the control of the main board; And a keypad having a plurality of function keys for the user to operate the functions.

The cell unit has a structure in which a plurality of battery packs are connected in parallel, and the cartridges are connected in series to increase the voltage of the cell unit.

The cartridge includes a voltage meter for measuring a voltage of the cell unit; A temperature measuring device for measuring a temperature of a cell mounted inside the cell unit; And a can communication unit for transmitting the measured voltage and temperature to the main board.

Further, the battery energy storage device may include a rack for mounting the plurality of cartridges.

According to the present invention, a large-capacity energy storage device can be connected to a system of a wind turbine generator to provide a stable power supply to the system, and an optimal air conditioning function can be performed by adding a constant temperature / There are advantages.

In addition, according to the present invention, a battery energy storage device and a bidirectional power control device can be implemented in a single container, and the charging and discharging control of the battery energy storage device and the power grid connection can be efficiently performed through the bidirectional power control device There is also.

In addition, according to the present invention, a cell unit having a parallel structure is developed in the form of a cartridge having a series structure for boosting, thereby providing an optimal battery energy storage device through serial / parallel combination.

1 is a configuration diagram of a container type energy storage device for a wind turbine according to a preferred embodiment of the present invention,
FIG. 2 is a structural view of a container type large capacity energy storage device according to the present invention;
FIG. 3 is a block diagram of an embodiment of the energy storage device (ESS) of FIG. 1;
4 is a perspective view of a cell unit embodied in the present invention,
5 is a configuration diagram of a cartridge formed by combining cell units in a serial form in the present invention,
6 is a view showing a rack frame connection in which a plurality of cartridges are formed in the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a container type energy storage device for a wind power generator according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of a container type energy storage device for a wind turbine according to a preferred embodiment of the present invention. The blade 10, the power transmission device 20, the generator 30, the power conversion device 40, Device 50 and a system.

The blade 10 plays a role of obtaining rotational energy due to wind. For example, the blade 10 is mounted on a rotatable shaft and serves to produce rotational energy from the wind.

The power transmission device 20 serves to transmit the rotational energy obtained from the blade 10 to the generator 30 at the downstream stage. The power transmission device 20 may be implemented as a gearbox and converts the rotational speed of the rotational energy obtained by the blade 10 into a rotational speed suitable for electric power generation through the gear box.

The generator 30 serves to generate electrical energy using the rotational force transmitted through the power transmission device 20. [

The power conversion device 40 converts electrical energy produced by the generator 30 into a form suitable for supplying to the system. For example, the power conversion device 40 converts the DC power acquired by the generator 30 into an AC power suitable for use in the system.

The energy storage device 50 charges the converted power from the power conversion device 40 and supplies the charged power to the system when the power supplied to the system is less than a certain level, And the like.

The energy storage device 50 controls the charging of the electric energy converted in the power conversion device 40 and controls the discharging of the charging power when the supply power of the system is less than a predetermined level to supply power to the system A bidirectional power control system (PCS) 51 for charging and discharging electrical energy, and a battery energy storage system (BESS) for discharging electrical energy. Here, the bi-directional power control device 51 and the battery energy storage device 52 are preferably integrated together in one container.

As shown in FIG. 2, the energy storage device 50 is provided with a constant temperature and humidity control unit 54 for performing constant temperature and humidity control according to the temperature inside the container or the temperature of the cell unit in the battery energy storage device. A fire extinguishing device 55 for extinguishing a fire extinguishing liquid when fire is detected, and a bilateral door 57 for entering and exiting the manager is provided at a predetermined position of the container. In addition, the energy storage device 50 is provided with a ventilation blind door 56 at one side thereof, and an outdoor unit 53 for constant temperature and humidity is also provided.

3, the bidirectional power control device 51 detects a current of power supplied to the system from the power conversion device 40, and when the detected current is an overcurrent, A primary protection circuit 51a for applying a voltage to the primary protection circuit 51a; A harmonic filter 51b for removing harmonics included in the AC power source; A power converting unit (51c) for converting AC power from the harmonic filter to DC power and outputting it as charging energy and converting DC power as discharge energy into AC power; A secondary protection circuit 51d that detects a current supplied from the power conversion unit 51c to the battery energy storage unit 52 and automatically performs a power shutdown operation when the current is overcurrent; A main central processing unit 51e for controlling the bidirectional power conversion of the power conversion unit 51c, controlling the constant current and the constant voltage charging, and controlling the air conditioning control and the transmission of the monitoring result according to the device monitoring result; A monitoring device 51f for measuring the power quality (current THD), measuring the temperature, and detecting the fire; And a can communication unit 51 for performing air conditioning control and monitoring result transmission under the control of the main central processing unit 51e.

The battery energy storage device 52 includes a primary protection circuit 52a that detects a current of the charging power supplied from the bidirectional power control device 51 and performs a power-off operation when the detected current is an overcurrent; A plurality of cartridges (52b) having a plurality of cell units storing the charging power and discharging stored power; A secondary protection circuit (52c) interposed between the cartridge (52b) and the primary protection circuit (52c) and interrupting power supply when an overcurrent is contained in the power supply or the discharge power supply charged in the cartridge (52b); A main board 52d that detects the power state of the cartridge 52b and controls charging and discharging according to the detected power state; A liquid crystal display (LCD) 52e for visually displaying the energy charging state of the battery energy storage device 52 under the control of the main board 52d; And a keypad 52f having a plurality of function keys for the user to operate the functions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, the blade 10 is mounted on a rotatable shaft to produce rotational energy from the wind, and the power transmission device 20 is configured to rotate the rotational speed of the rotational energy obtained from the blade 10 through a gear box And transmits it to the generator (30).

Then, the generator 30 generates electrical energy using the rotational force transmitted through the power transmission device 20. [ The produced electric power is transmitted to the electric power conversion device 40. The electric power conversion device 40 converts the transferred electric energy into a form suitable for supplying the electric power to the electric power system, and supplies the converted electric energy to the electric power system. For example, the power conversion apparatus 40 converts the DC power acquired by the generator 30 into an AC power suitable for use in the system.

The above wind power generation principle is the same as the wind power generation principle used in a general wind power generation system.

The present invention relates to a system for storing energy in cooperation with a wind power generation system as described above and to supply stored energy to the system when the wind power generation system can not provide wind power and to supply power to the system in a stable manner. The device 50 is newly implemented.

The energy storage device 50 controls the charging of the electric energy converted by the power conversion device 40 and controls the discharging of the charging power when the supply power of the system is less than a predetermined level, A bidirectional power control system (PCS) 51 for supplying power to the system, and a battery energy storage system (BESS) for charging and discharging electrical energy.

The bidirectional power control device 51 detects a current of power supplied to the system from the power conversion device 40 in the primary protection circuit 51a and automatically performs a power cutoff operation when the detected current is an overcurrent Thereby preventing the energy storage device 50 from being damaged due to surge voltage or overcurrent.

The AC power supply through the primary protection circuit 51a is removed from the AC power via the harmonic filter 51b and converted into a DC power suitable for charging through the power conversion section 51c and output to the charging power supply .

When the surge voltage is included or the overcurrent is included in the rechargeable power source, the rechargeable power is supplied to the battery energy storage device 52 through the secondary protection circuit 51d. Is blocked.

In addition, the monitoring device 51f of the bi-directional power control device 51 measures the power quality (current THD), the temperature inside the container or the temperature of the cell unit, and monitors the fire in the container. The measured and monitored result information is transmitted to the main central processing unit 51e. The can communication unit 51 communicates with the can communication unit included in the cartridge 52b to acquire the voltage and temperature of the cell unit and delivers it to the main central processing unit 51e.

The main central processing unit 51e controls the operation of the air conditioning system and the fire extinguishing system based on the result information monitored by the monitoring device 51f. For example, when the temperature is higher than the set reference temperature, the ventilating fan (or blower fan) is operated or the air conditioner is operated to lower the internal temperature of the container. If the humidity is high, do. Here, the constant temperature and humidity chamber 54 can use the already known GT 020 AUF. When a fire is detected, the fire extinguishing device 55 is operated to fire the fire extinguishing liquid to suppress the fire. Here, the fire extinguishing device 55 is a cabinet type automatic fire extinguishing device, and the known FKBP-501 can be used.

The main central processing unit 51e also sets the charging mode of the power conversion unit 51c to the constant current (CC) mode or the constant voltage (CV) mode, according to the measured voltage of the cell unit measured from the battery energy storage device 52 . Here, since the control of the constant voltage mode or the constant current mode is well known in the battery charging method, a detailed description thereof will be omitted in the present invention.

Next, when the charging power is supplied from the bidirectional power control device 51, the battery energy storage device 52 detects the current of the charging power supplied from the primary protection circuit 52a, and when the detection current is an overcurrent And performs a power-off operation to prevent the battery energy storage device 52 from being damaged due to an overcurrent.

If the supplied power is not an overcurrent, the charging power source that has passed through the primary protection circuit 52a is again detected to be overcurrent through the secondary protection circuit 52c. At this time, if the current is within the normal current range, To charge the energy.

In order to systemize the unit cells, the battery energy storage device 52 of the present invention develops a cell unit as shown in FIG. 4 having a parallel structure that has been previously developed as a cartridge 52b having a series structure for boosting, We have implemented systemization through parallel combination.

For example, the cell unit has a structure in which six 3.2 V 20 Ah battery packs are connected in parallel, and one cartridge 52b has six cell units 1, 2, 3, 4, 5, and 6 ) Is connected to the cartridge bus bar to constitute a total voltage of 19.2 V and a rated discharge current of 140 Ah. It is desirable that the cartridge is designed so as to be capable of discharging heat generated at the time of high output.

Inside this cartridge 52b, although not shown in the figure, a voltage meter for measuring the voltage of each of the six cell units housed and a temperature sensor for sensing the temperature of the cell mounted inside the cell unit are included. The LTC6803 is used as a measurement sensor to measure the voltage and temperature of the cell unit. It includes a 12-bit analog-to-digital converter (ADC), a precision voltage reference, a high voltage input multiplexer and a serial interface. Each LTC6803 is capable of measuring up to 12 individual cells arranged in series and it is desirable to measure the voltage of six cell units to match the number of cell units in the cartridge. The LTC6803's maximum total measurement error is guaranteed to be less than 0.25% at -40 ° C to 125 ° C. Each cell is monitored for low and overvoltage conditions, and a MOSFET can be used to discharge an overcharged cell.

In addition, a can communication unit for communicating the measured voltage and temperature to other devices is added to the inside of the cartridge 52b. The 850 kW class battery energy storage 52 is equipped with a total of 40 cartridges and is connected in series with one battery management system (BMS). The connection between the cartridge and the battery management system is connected by a can communication, connected by two bus lines, and electrically communicates with differential communication, and is very strong in electrical noise. In addition, can communication is a standard protocol, so marketability is excellent, and in the case of the can communication, the multi-master communication in which all the can controllers can become the master is possible, so that the 40 cartridge boards can be mastered with each other and can be connected to the multi. The voltage and the temperature measured in the cartridge are displayed on the liquid crystal display 52e through the main board 52d so that the administrator can visually recognize the state of the charging power source, the temperature state, and the like. The administrator can set the function or change the set function through the keypad 52f as needed.

Although not shown in the drawings, such a plurality of cartridges are preferably mounted in a single rack. Normally, 32 cartridges are connected in series and mounted in a rack. 6, a rack frame is designed in a 19 "open rack structure, in which a plurality of cartridges, a battery management system, and a control device are spatially separated from each other The power stored in the battery energy storage device 52 is supplied to the sales or the system in the future.

Next, the bidirectional power control device 51 of the energy storage device 50 monitors the power supplied to the system in real time, and if the power supplied to the system is below a predetermined level (based on a preset reference value, , The power stored in the battery energy storage device 52 is discharged to supply power to the system.

For example, the DC power discharged from the battery energy storage device 52 is converted to a predetermined AC power fixed frequency (50 / 60Hz) required by the system through the power conversion section 51c. The thus converted AC power is supplied to the system through the primary protection circuit 51a by removing the harmonics included in the AC power via the harmonic filter 51b. Here, the power converter 51c is preferably implemented as a three-phase full-bridge having a VSI (Voltage Source Inverter) of a two-level switching scheme.

Therefore, even when the wind power generator can not normally generate power, the power is stably supplied to the system.

Although the present invention has been described in detail with reference to the above embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

The present invention is effectively applied to an energy storage device technology for stably supplying electric power to a system in conjunction with a wind turbine generator.

10: Blade
20: Power transmission device
30: generator
40: Power converter
50: Energy storage device
51: Bi-directional power control device
51b: Harmonic filter
51c:
51e: main central processing unit
51g: Can communication section
52: Battery energy storage device
52b: Cartridge
52d: Motherboard

Claims (10)

A blade for obtaining rotational energy by the wind;
A power transmitting device for transmitting the rotational energy obtained from the blade to the rear end;
A generator for generating electrical energy using a rotational force transmitted through the power transmission device;
A power converter for converting electric energy produced by the generator into a form suitable for supplying to the system; And
And an energy storage device for charging the power converted by the power conversion device and supplying the power to the system when the power supplied to the system is less than a predetermined level,
Wherein the energy storage device controls the charging of the electric energy converted by the power conversion device and controls the discharging of the charging power to supply power to the system when the supply power of the system is less than a predetermined level, And a battery energy storage device for charging and discharging electric energy.
The container type energy storage device for a wind power generator according to claim 1, wherein the bidirectional power control device and the battery energy storage device are integrated together in one container.
[3] The container type energy storage device for a wind power generator according to claim 2, wherein the energy storage device further comprises a constant temperature and humidity air conditioner for performing a constant temperature and humidity control according to the temperature inside the container or the temperature of the cell unit in the battery energy storage device. .
The container type energy storage device for a wind power generator according to claim 2, wherein the energy storage device further comprises a fire extinguishing device for extinguishing the fire extinguishing liquid when fire is detected inside the container.
The bidirectional power control apparatus according to claim 1, wherein the bidirectional power control apparatus includes: a primary protection circuit that detects a current of power supplied to the system from the power conversion apparatus and automatically performs a power shutdown operation when the detected current is an overcurrent; A harmonic filter for removing harmonics included in the AC power supply; A power converter for converting AC power from the harmonic filter to DC power and outputting it as charging energy and converting DC power as discharge energy into AC power; A secondary protection circuit that detects a current supplied from the power conversion unit to the battery energy storage device and automatically performs a power shutdown operation when the current is an overcurrent; And a main central processing unit for controlling the bidirectional power conversion of the power conversion unit, controlling the constant current and the constant voltage charging, and controlling the air conditioning and fire extinguishing device.
[6] The bidirectional power control device of claim 5, wherein the bidirectional power control device comprises: a monitoring device for measuring power quality (current THD), measuring temperature, and detecting fire; Further comprising a can communication unit for acquiring a voltage measurement value and a temperature measurement value of the cell unit acquired by the battery energy storage unit (52) and transmitting the acquired voltage measurement value and the temperature measurement value to the main central processing unit .
The battery energy storage device of claim 1, wherein the battery energy storage device comprises: a primary protection circuit for detecting a current of a charging power supplied from the bidirectional power control device and performing a power-off operation when the detection current is an overcurrent; A plurality of cartridges each containing a plurality of cell units for storing the charging power and discharging stored power; A main board for detecting a power state of the cartridge and controlling charging and discharging according to the detected power state; A liquid crystal display for visually displaying an energy charging state of the battery energy storage device under the control of the main board; And a keypad having a plurality of function keys for a user to operate a function.
The container type energy storage device for a wind power generator according to claim 7, wherein the cell unit has a structure in which a plurality of battery packs are connected in parallel, and the cartridges are connected in a series structure for boosting the cell units.
9. The apparatus of claim 8, wherein the cartridge further comprises: a voltage meter for measuring a voltage of the cell unit; A temperature measuring device for measuring a temperature of a cell mounted inside the cell unit; And a can communication unit for transmitting the measured voltage and temperature to the main board.
The container type energy storage device of claim 7, wherein the battery energy storage device comprises a rack for mounting the plurality of cartridges.

Images