KR101332304B1 - surge protecting system for energy storage apparatus and method therefor - Google Patents

Abstract

In the present invention, the brain discharge protection system for a large-scale energy storage device is identified in real time and the event information regarding the burnout and operation of the lightning arrester due to the brain discharge is integrated and managed during the periodic site inspection. The state monitoring technology for 'remote monitoring using a brain discharge protection system of a large-scale energy storage device' to maintain a stable operation state using event information and state information is disclosed.

Description

Surge protection system and energy storage apparatus and method therefor}

The present invention relates to a surge protection system and method for protecting a large-capacity energy storage device from direct lightning strikes or indirect lightning strikes. More particularly, the present invention relates to a dispersion using renewable energy by increasing the frequency of lightning strikes due to recent climate change. The present invention relates to a surge protection system and a method for maximizing the brain protection efficiency of a brain discharge protection system for an externally installed large-scale energy storage device for stabilizing power quality and securing reliability in linking a power system to a power system.

Recently, the paradigm shift of the power industry has come to accelerate the change to smart grid due to the expansion of new and renewable energy with low carbon green growth. Conventional power grids require long-distance power transmission facilities by producing power from centralized power generation such as thermal power and nuclear power and delivering it to the customer through the power grid, and in particular, focusing on supplying power to the customer. It has a weak structure for power outages. In addition, in order to cope with the peak peak power demand occurring in each season, large-scale backup power is required, and in many cases, it is composed of inefficient power system due to low utilization rate of power facilities. Looking at the future electricity demand, the trend is continuously increasing, and the shortage of supply and surplus power in power supply and demand is expected to increase gradually, resulting in the burden of the construction of new power generation facilities and lower utilization rate. As a means to solve these problems, the global task is to build a distributed power storage system by expanding MW-class power storage facilities and to store surplus power so that smooth and stable power supply and supply can be possible at times of high demand. The energy storage system has come into the spotlight as an alternative. In addition, as the proportion of power supply using renewable energy is increasing, attention is focused on energy storage devices as an alternative to power quality problems.

1 is a system configuration diagram for storing and drawing power to a conventional energy storage device.

The system shown in FIG. 1 is connected to an AC line 1 connected to a power system through an AC / DC converter 2 to receive AC (AC) power from the AC line 1 to convert DC (DC) power. Stored in the energy storage device 4, DC power is drawn from the energy storage device 4 is converted into AC power and supplied to the AC line (1). In addition, an AC / AC converter 3 is connected to the AC line 1 to convert AC power of the AC line 1 to be supplied to the monitoring and control unit 5, and the monitoring and control unit 5 is an energy storage device 4. In order to control the charging or discharging of the energy storage device (4) by driving the switching means not shown installed in the), and to monitor the voltage, current state of the energy storage device (4).

In addition, since the energy storage device 4 is made of an explosive material such as lithium, various protection equipments should be provided, and a SPD (Surge Protecting Device) to protect each device from surges input from the AC line 1. 1 to 5 are installed.

However, when a brain discharge occurs in the region where the energy storage device 4 is installed or in an adjacent region, the lightning discharge protection system is operated by the lightning current induced in the power line and the communication line, and immediately occurs when the damage caused by the brain discharge occurs. It was difficult to cope with the problem, and the phenomenon could be identified only by visiting the site.

In addition, as the size of the energy storage device 4 gradually increases in size, the energy storage device 4 is stored in a separate independent facility, and surges are introduced into the energy storage device 4 due to various lightning discharges. The need to grasp in real time was raised.

In addition, the lightning discharge required remote monitoring status monitoring technology that integratedly manages the event information regarding the burnout and operation of the lightning arrester.

The problem of the present invention is to identify the state of the brain discharge protection system for a large-scale energy storage device in real time and to manage the event information related to the burnout and operation of the lightning arrester due to the brain discharge, the brain discharge during periodic site inspection It provides status monitoring technology for 'remote monitoring using brain discharge protection system of large-scale energy storage device' to maintain stable operation state by using event information and status information of protection system.

The solution means for solving the above problem is to provide the energy storage module from the surge flowing through the shield housing and the DC (direct current) power lines introduced into the shield housing of the metal housing the energy storage module including battery units therein; A surge protection system of an energy storage module comprising surge protectors (SPDs), the surge protection system comprising: current detection circuits for sensing a current flowing in each line of the surge protectors; A monitoring device receiving a byte formed of bits corresponding to output signals output from the current detection circuits; And a determination device for determining an inflow path and an outflow path of surges flowing into the surge protectors by a byte input to the monitoring device by a server installed inside or connected to the outside of the monitoring device, wherein the shielding housing includes: A lightning arrester is installed, and a communication line for communicating with the outside is connected to the monitoring device, and a grounding line connected to a grounding line of the surge protectors is installed in the shielding housing, and a surge is provided in each of the arrester, the communication line, and the grounding line of the shielding housing. A current detection circuit for detecting the flow of current is provided.

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According to the present invention having the above-described problems and solutions, the shielding housing, the rack, and the shielding shield the brain flowing into the energy storage module from the atmosphere by the double, triple, and inflow from the AC power line, DC power line The brain current is discharged to the SPD, and the current flowing through each SPD line is detected through the current detection circuit to determine the inflow path and the discharge path of the brain current, thereby facilitating facility management and maintenance inspection. In addition, when the surge is detected with a short holding time, the current detection circuit detects the surge and returns to the original state by the reset signal of the MPU. Therefore, the MPU has sufficient time to detect the inflow of the surge. have. In addition, the present invention receives the state signal of the delayed current detection circuits as described above in byte units, it is possible to determine the flow of the brain current by the inflow path, the discharge path is set by byte number. In addition, the input byte number is transmitted to an external server through a communication line to manage brain surges.

In addition, in the present invention, data is formed in units of bytes according to the state of output signals according to the disconnection state of the disconnector so that it is possible to determine whether to replace the SPD in or outside the monitoring apparatus.

1 is a system configuration diagram for storing and drawing power to a conventional energy storage device.
2 is an overall block diagram illustrating an embodiment of the present invention.
3 is a block diagram of a detection circuit connected to the monitoring device and the monitoring device of the present invention.
4 is a connection diagram of a surge protection device connected to an AC power line and a detection circuit connected to the surge protection device in the present invention.
5 is a connection diagram of a surge protection device connected to a DC power line and a detection circuit connected to the surge protection device in the present invention.
6 is an embodiment of the detection circuit of the present invention.
7 is a flowchart illustrating a system setting process in an embodiment of the present invention.
8 is a flow chart showing the overall operation of the present invention.

2 is an overall block diagram illustrating an embodiment of the present invention.

The shielding housing 102 of FIG. 2 has a polyhedron, preferably a hexahedron shape made of metal, to shield the internal lightning by primarily shielding a direct lightning strike. Inside the shielding housing 102, a rack 104 made of a metal material on which battery units to which battery packs of the energy storage module 118 are connected is mounted is installed. The rack 104 performs secondary shielding on the battery units constituting the energy storage module 118 therein, and a shielding line 112 is installed inside the rack 104 to provide the energy storage module 118. Protect space surges.

In addition, when each lead wire passes through the boundary area of each facility, SPD_1, 2, 3, 4, which is a surge protector device (SPD), are installed to protect the equipment from the induced surge flowing along the lead wire. . V1 and I1 are values after the induced surges of surge voltage V0 and surge current I0 pass through surge protectors SPD_1, 2, 3, and 4, respectively.

The DC power line shown in FIG. 2 is connected to the AC line 1 of FIG. 1 to supply DC power to the DC switchboard 106 in the shielded housing 102, and the DC switchboard 106 is an energy storage module 118. Converts the DC power of the AC / DC converter 2 into the charging rated power when charging the battery and reversely converts the discharge power of the energy storage module 118 into the rated input power of the AC / DC converter 2 when discharging. do.

Also, the AC power line of FIG. 2 is connected to an AC switchboard 108 installed in the shielding housing 102 by a line connected to the AC line 1 of FIG. 1, and the AC switchboard 108 is connected to the monitoring device 110 and the shielding housing. It is connected to an AC load, such as a lamp installed in the 102, a ventilation fan lamp to supply AC power.

In addition, the energy storage module 118 includes a plurality of battery units connected in parallel and a battery management system (Battery Management System) for monitoring and managing each battery unit.

In addition, the monitoring device 110 includes SPD_1 for protecting the surge flowing from the DC power line, SPD_3 for protecting the surge flowing from the AC power line, the current of the ground wire 116, and a local lightning protection device such as an arrester 114. It is connected to the detection circuit for detecting the state information of the children, and receives the state information of the local power element every predetermined period from the detection circuit and transmits to a server (not shown) installed outside through a communication line.

At this time, the state information generated by the monitoring device 110 is preferably formed in a byte (byte) unit.

3 is a block diagram of a detection circuit connected to the monitoring device and the monitoring device of the present invention, Figure 4 is a connection diagram of a detection circuit connected to the surge protection device, and a surge protection device connected to the AC power line in the present invention, 5 is a connection diagram of a surge protection device connected to a DC power line and a detection circuit connected to the surge protection device in the present invention, and FIG. 6 is an embodiment of the detection circuit of the present invention.

In the present invention, the monitoring device 110 receives a signal from the detection circuits, a signal input and output unit 13 for outputting a control signal to the detection circuits, and periodically input data in bytes from the signal input and output unit 13 A microprocessor unit (MPU) 11 for receiving a reset signal to each detection circuit and a data transmission / reception unit 12 for transmitting and receiving data to and from an external server through a communication line under the control of the MPU 11. )

The detection circuit of the SPD_3 connected to the monitoring device 110 includes a current detection circuit (R) 131 for detecting a brain current induced in a current transformer installed on R, S and T of the SPD_3, as shown in FIGS. Disconnector detection circuit (R) for detecting disconnection state and generating disconnection signal when disconnection of current detection circuit (S) 132, current detection circuit (T) 133, and SPD_3 is operated to block inflow surge ) 134, disconnector detection circuit (S) 135, disconnector detection circuit (T) (137).

At this time, disconnection detection of the disconnection detection circuit (R), (S), (T) is the disconnection detection sensor (not shown) configured to flow a current as the fuse of the disconnection as shown in FIG. C).

The detection circuit of SPD_1 connected to the monitoring device 110 includes a current detection circuit (+) 137 for detecting current of the + line, a current detection circuit (-) of the-line (138), + as shown in FIGS. Circuit breaker detection circuit (+) 139 for detecting disconnection state of line disconnector and disconnector detection circuit (-) 140 for detecting disconnection state of disconnector of-line, and brain current detection of current detection circuit It is detected by the current transformer installed in, disconnection of the disconnector is made by the disconnection detection sensor.

The input terminals C1-1 and C1-2 of the detection circuit shown in FIG. 6 are connected with a disconnection sensing sensor for monitoring the disconnection state of the fuses of FIGS. 4 and 5 or a current transformer inducing current from the flow of the brain current. By delaying the input signal by the detection circuit, the MPU 11 can be recognized.

In the case of a brain discharge, as shown in IEC 61643, several hours of energy retention time are available, and this brain discharge energy has enough energy to destroy electrical installations and facilities. To detect short holding times of several milliseconds, an additional supervisory circuit is added to the MPU. This means that the high voltage is reduced to a low voltage of 5V used by the MPU by using a surge suppression / coupling circuit in the MPU which operates as a pulse. Noise filtering significantly lowers the recognition rate. To solve this problem, the input signal is delayed to be recognized by the MPU using the detection circuit illustrated in FIG. 6.

The detection circuit includes a bridge BD where the input signals of the input terminals C1-1 and C1-2 are rectified, a photodiode PD which is connected to the bridge BD, and emits light by the rectified input signal, and a photo. The signal input unit 161 made of a protection element composed of resistors and capacitors for limiting and smoothing the current input to the diode PD, and conducts when the photodiode PD of the signal input unit 161 emits light. A resistor R1 installed between the emitter of the phototransistor PT and the phototransistor PT and ground, a resistor R2 connected to the gates of the phototransistor PT and escral SCR, and both ends of R2. On the MPU 11 of the monitoring device 110 and the SCR driver 162 made up of a capacitor C1 and a resistor R3 provided between the ground and the ground, and an SCR conducted by a voltage applied to the resistor R2. Transistor Q1 conducted by the reset signal applied by the The base is connected via an SCR reset unit 163 for resetting the SCR when the reset signal of the MPU 11 is applied, and the resistors R5 and R8 and R8 connected to each other. The output voltage MPU_INPUT is drawn from the collector, and the signal output unit 164 draws out the low voltage when the signals of the input terminals C1-1 and C1-2 are input.

The signal MPU_INPUT of the output terminal of the detection circuit configured as described above maintains a high state when no signal is input to the input terminals C1-1 and C1-2, and the input terminals C1-1, The photodiode PD emits light when the brain current is inputted by the current transformer or the detection current is input by the disconnection detection sensor, and when the photodiode PD emits the phototransistor PT, The SCR conducts and eventually the MPU_INPUT transitions to a low potential, resulting in a low signal. Once the SCR is turned on, the state is maintained continuously. The MPU_INPUT remains low until a separate reset signal is supplied to the SCR. Consequently, the detection circuit returns the input terminals (C1-1) and (C1-2). It operates as a delay circuit to delay and output the signal of.

The MPU 11 transmits a reset signal to the signal input / output unit 13 when an event occurs or for each period, and supplies a reset signal to the SCR reset unit 163 from the signal input / output unit 13 to provide an SCR. By resetting, the MPU_INPUT goes high and prepares for the next event.

The state of the SPD, lightning arrester, ground line, communication line is detected by such a detection circuit and stored in the monitoring device 110 in real time, and transmitted to an external server.

The MPU 11 of the monitoring device 110 receives the output MPU_INPUT of each detection circuit in units of bytes.

Table 1 below is an example of defining a bit-by-bit number of bytes input to the MPU in any mode.

Bit variable definition in mode setting Bit 8 7 6 5 4 3 2 One - - AC power DC power - - value Lightning rod R phase S phase T phase (+) (-) Communication Ground
(Neutral)

Table 1 shows a detection circuit for detecting brain current flowing in SPD_3 connected to the AC power line, a detection circuit for detecting brain current flowing in SPD_1 connected to the DC power line, a detection circuit for detecting brain current flowing from the communication line, and a ground wire. Parameter definitions when the MPU_INPUT is input from the detection circuit that detects the discharged brain current, and the following table shows the bit definitions in the mode where only a specific detection circuit is installed.

When AC 3Φ3W / 3Φ4W mode is set Bit 8 7 6 5 4 3 2 One - - AC power DC power - - value Lightning rod R phase S phase T phase - - - Ground
(Neutral)

Table 2 shows the three-phase three-wire or three-phase four-wire alternating current mode, in which the output of the detection circuit for each phase of SPD_3 is assigned to the seventh, sixth, and fifth bits, The output is assigned to the first bit, and no lightning current flows from the arrester, communication line, or DC power line. As described above, when the present invention is applied to the site and installed and operated, a detection circuit is installed at a necessary portion and operated according to modes. Tables 3 and 4 show exemplary modes.

When setting DC 2W mode: When (-) is ungrounded Bit 8 7 6 5 4 3 2 One - - AC power DC power - - value Lightning rod - - - (+) (-) - Ground
(Neutral)

When setting AC 3Φ3W / 3Φ4W mode and DC 2W mode Bit 8 7 6 5 4 3 2 One - - AC power DC power - - value Lightning rod R phase S phase T phase (+) (-) - Ground
(Neutral)

Table 5 is a bit-by-bit variable definition of another byte for checking the disconnection state of the disconnector in the present invention.

Bit 8 7 6 5 4 3 2 One - - AC power DC power - - value - R phase S phase T phase (+) (-) - -

The disconnector is not installed in the communication line, the ground line, or the arrester, but is only installed in the R, S, T phases of the SPD_3 of the AC power supply and the DC power supply (+) and (-) lines of the SPD_1 .

In this way, in order to understand the flow of surge introduced by the brain discharge, the MPU 11 detects 1 byte (8 bits) of the variables of Table 1, and detects 1 byte of the variables of Table 5 to identify the disconnection state of the disconnector. . In the initialization state, each bit is set to the Active High state, and the active state is inverted upon surge inflow through each detection circuit, and the MPU recognizes this to identify the inflow path and discharge path according to the brain discharge.

Table 6 below describes the states defined according to the byte values in Table 1. In Table 6, byte-0 indicates that all detection circuits are normal with 'high' state when all bits are 1, and byte-1 indicates that only surge current is detected on ground only when no surge is input. Is indicated by X because it can't exist, and byte-2 means the state that surge current is drawn to the communication line but is not discharged to ground, and this state is indicated by X because it can't exist. -3 indicates that the detection circuit of the communication line and the detection circuit of the ground line are in operation, and since the brain current flowing into the communication line is discharged through the ground line, it is indicated as communication → ground. The following byte-by-byte display method is performed in the same manner.

Bits 0 to 127 of Table 6 are assigned a bit of the arrester as '1', and the corresponding bit of the arrester is '1' means that the arrester is not installed or surge is not introduced to the arrester. Table 6 omits the state that the corresponding bit of the arrester is '0', that is, the surge is introduced into the arrester.In Table 6, replace the corresponding bit of the arrester with '0' instead of '1'. You can configure the table up to.

7 is a flowchart illustrating a system setting process in an embodiment of the present invention.

In the present invention, the current time setting is prioritized so that the setting time of the setting devices which are input in the subsequent order is set so that the history management of the devices can be accurately performed.

After the current time is set, the connection state of the lightning rod is input, the AC power connection state is input, the DC power connection state is input, and the communication line connection state is input.

8 is a flow chart showing the overall operation of the present invention.

When the system setting of FIG. 8 is ended and a specific event occurs while the monitoring apparatus 110 is normally operating (S1, S2), after counting the variable which generated the event and storing it in the memory (S3). If there is no failure by storing the time at which the event occurred (S4), calculating the cumulative event occurrence (S5), and checking the state of the disconnectors by reading the byte composed of the bits allocated to the disconnectors described in Table 5. The above operation sequence is repeated, and if there is a failure, an alarm is generated and a failure coefficient and time information are provided to an external server, and when the stop state is reached due to a system failure, the system is stopped (S6) and (S7). ), (S8)

102: shielded housing 104: rack 106: DC switchboard
108: AC switchboard 110: monitoring device 112: shielded wire
114: lightning arrester 116: ground wire
118: energy storage module 120: AC load

Claims (8)

Surge protector (SPD) to protect the energy storage module from the surge flowing through the DC (direct current) power wires that enter the shielded housing, the metal housing housing the energy storage module including battery units therein; In a surge protection system of an energy storage module comprising devices:
Current detection circuits for sensing a current flowing in each line of the surge protectors;
A monitoring device receiving a byte formed of bits corresponding to output signals output from the current detection circuits;
And a determination device for determining an inflow path and an outflow path of surges flowing into the surge protectors by a byte input to the monitoring device by a server installed inside the monitoring device or connected to the outside.
A lightning arrester is installed in the shielding housing, a communication line is connected to the monitoring device for communication with the outside, and a shielding housing is provided with a grounding line connected to a grounding line of the surge protectors, and the lightning arrester, the communication line, and A surge protection system for an energy storage module, characterized in that a current detecting circuit for detecting that a surge current flows in each ground line. delete delete delete 2. The disconnection detecting circuits of claim 1, wherein disconnection detection sensors through which current flows when disconnection devices of the surge protectors are disconnected and disconnection detection circuits connected to the disconnection detection sensor to output a disconnection signal when the disconnection device is disconnected. Further installed, the monitoring device is a surge protection system of the energy storage module, characterized in that for receiving the disconnection state of the disconnection detection circuits in bytes (byte).
The surge protection system according to claim 1, wherein the output signal of the current detection circuit is a delay circuit reset by a reset signal input by the monitoring apparatus. In claim 1, each bit forming the byte input to the monitoring device, respectively, R, S, T phase of the AC power supply line, (+), (-) of the DC power supply line, current detection connected to the communication line, ground line, lightning arrester At least one of the output states of the circuits is assigned, and the unassigned bits are assigned a steady state of one.
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