KR101030925B1 - Solar power generation system with monitoring and neutral line replacement - Google Patents

Abstract

PURPOSE: A solar generating system is provided to enable a user to easily check a failure position by monitoring the contact failure of a solar cell module. CONSTITUTION: A solar cell module array(100) converts and outputs solar energy to electrical energy. A connection case(200) couples and outputs the converted electrical energy. A power converter(300) receives the electrical energy from the connection case though a power line and converts it AC power. A monitoring unit(400) controls a power circuit breaker according to a control command from a manager terminal. A neutral-conductor substituting unit(500) is installed between the power converter and a power supply company.

Description

Solar power generation system with monitoring and neutral line replacement

The present invention relates to a photovoltaic power generation system equipped with a monitoring and neutral wire replacement function, and more particularly, a poor contact of each line of the solar cell module in the junction box and a poor line contact between the junction box and the inverter, and a power line and an inverter. Monitoring and contact of neutral wires are provided to monitor the contact failure between them and to facilitate the positioning of fault points, and to prevent the load of equipment from being burned out due to voltage unbalance in the event of neutral wire break of AC power converted and supplied by inverter. It relates to a solar power system provided.

In general, widely used fossil energy is limited in amount, and sometime it is exhausted and emits various pollutants, so most countries are developing alternative energy that can be used instead.

There are many kinds of energy that can replace fossil energy, tidal wave to generate energy using tidal difference, wave power to generate energy using waves, wind power to generate energy using wind power, And there is geothermal energy that uses energy in the ground to generate energy, and solar energy is the source of these energy.

Photovoltaic power generation that produces such solar energy refers to a system for generating electricity by converting the sun and energy into electrical energy, and the generated direct current electrical energy is converted into alternating current electrical energy through a power converter (inverter).

The generated electricity is connected to the KEPCO system and supplied to the load side, and the remaining power is transmitted back to the KEPCO system. The electricity that is lacking here is supplied by KEPCO.

When the system is constructed in connection with the system as described above, the solar cell module is used in the form of an array, and the junction box includes a circuit group for connecting with the solar cell module, and a power line is connected between the junction box and the inverter which is a power converter. To connect.

However, such a general photovoltaic power generation system transmits power to an inverter through four wires by tying a plurality of solar cell modules in a junction box. In this case, there is a disadvantage in not monitoring which solar cell module has a poor contact. In the case of a problem in the amount of power generation, it is necessary to check the solar cell modules individually, which takes a lot of repair time and is difficult to repair.

In this case, when contact failure occurs in a specific circuit, there is no problem in the system in a short time, but in the long term, it causes a fire or a breakdown.

In addition, the general photovoltaic power generation system, the junction box and the inverter which is a power conversion device is connected to the power line, there is a disadvantage that can not detect the poor contact or disconnection of the power line line.

In addition, the photovoltaic power generation system as described above not only detects the disconnection of the neutral wire (N) when supplying the alternating current power converted from the inverter to the KEPCO system, but also does not provide a countermeasure against the disconnection of the neutral wire. This also caused a problem that the load side equipment was burned out.

Accordingly, the present invention has been proposed to solve various problems occurring in the general photovoltaic power generation system as described above.

The problem to be solved by the present invention is to monitor the contact failure of each line of the solar cell module, the line contact failure between the junction box and the inverter, the contact failure between the power line and the inverter in the junction box, to confirm the location of the fault location It is to provide a photovoltaic power generation system equipped with a monitoring and neutral line replacement function to provide ease.

Another problem to be solved by the present invention is to detect a contact failure in the photovoltaic power generation system, and to notify the manager when a contact failure is detected to facilitate the follow-up actions, to prevent further failure due to contact failure To provide a photovoltaic power generation system equipped with a monitoring and neutral line replacement function.

Another problem to be solved by the present invention is a photovoltaic power generation system equipped with a monitoring and neutral line replacement function that prevents the load device from being burned out by voltage unbalance in the event of a neutral wire break of the AC power supplied by the inverter. To provide.

Another problem to be solved by the present invention is to provide a remote control to quickly control the photovoltaic power generation system, and to provide a monitoring and neutral wire replacement function to prevent accidents that may occur due to poor contact or neutral wire disconnection It is to provide a photovoltaic power generation system.

According to a preferred embodiment of the present invention for solving the above problems "photovoltaic power generation system with monitoring and neutral line replacement function",

A solar cell module array for converting and outputting solar energy into electrical energy;

A junction box for coupling and outputting the electrical energy converted by the solar cell module array;

A power converter receiving electrical energy output through the junction box through a power line and converting the electrical energy into AC power;

Monitoring contact failures of each line in the junction box, failure of power line contact between the junction box and the inverter, and contact failure in the power converter, and if it is determined that the contact failure is performed, an alarm is performed and alert information is transmitted to the manager terminal. A monitoring device controlling a power breaker in accordance with a control command transmitted from the manager terminal remotely;

It is provided between the power converter and the KEPCO system, detects the phase of the three-phase four-wire (R, S, T, N) supply power input to the KEPCO system, and if the phase detection is detected it is determined to be a neutral disconnection and the neutral wire It is characterized in that it comprises a neutral wire replacement device to prevent the load connected to the single-phase power is burned out.

In the above monitoring device,

A power converter which detects and digitizes a power state value at a specific position in real time;

Converts the digital data into basic element information for determining power quality, generates power state data, calculates and extracts power quality based on the power state data, and analyzes the amount of change for each extracted power quality element. If a certain amount or more is converted, the result is applied by applying a fuzzy rule table for the change amount, and the result of the extracted fuzzy rule table is applied to a multi-faceted evaluation method to determine contact failure at a specific position, and to generate an alarm in case of contact failure. A controller for controlling transmission of alarm information to a manager terminal and controlling the power breaker according to a power cut control command transmitted remotely;

An alarm generator for generating an alarm for contact failure in association with the controller;

And a communication module for transmitting the alarm information in association with the controller and receiving a remote control command transmitted through wired / wireless communication from the remote and transmitting the received remote control command to the controller.

Neutral wire replacement device in the above,

A disconnection detector for detecting whether the neutral line is disconnected;

A controller for judging disconnection using the disconnection detection value output by the disconnection detector, and generating a control signal for replacing the neutral when disconnection;

It is characterized in that it comprises a neutral line protector to maintain the balance of the single-phase voltage by replacing the neutral line of the power line supplied to the KEPCO system according to the control signal generated by the controller.

The disconnection detector,

A phase detector for detecting phase signals of R, S, and T phases;

It characterized in that it comprises an image determination determiner to determine the phase if the level of any one of the R, S, T phase detected by the phase detector lasts for a predetermined time at a high level.

The neutral line protector,

A switch for connecting three phases (R, S, T);

It characterized in that it comprises a coil for maintaining the balance of the single-phase voltage by connecting the three-phase and the neutral neutral (N).

The neutral wire replacement device,

An alarm generator for alarming the disconnection of the neutral wire according to the alarm generation control signal output by the controller;

And an alarm release signal input unit configured to generate an alarm release signal and transmit it to the controller when an alarm release switch for alarm release is operated by an administrator after an alarm is generated by the alarm generator.

According to the present invention, in the photovoltaic power generation system, the contact failure of each line of the solar cell module, the poor contact of the line between the junction box and the inverter, and the poor contact between the power line and the inverter can be monitored within the junction box. There is an advantage to facilitate the identification.

In addition, according to the present invention, by detecting a contact failure in the photovoltaic power generation system, and if the contact failure is detected by notifying the manager to facilitate the follow-up measures, it is possible to prevent future failure due to contact failure There is an advantage.

In addition, according to the present invention, there is an advantage that it is possible to prevent the device of the load from being burned out due to voltage unbalance in the event of neutral disconnection of the AC power supplied by the inverter.

In addition, according to the present invention, it is possible to quickly control the photovoltaic power generation system even remotely, there is an advantage that can prevent accidents that may occur due to poor contact or disconnection of the neutral wire.

1 is an overall configuration diagram of a photovoltaic power generation system equipped with monitoring and neutral line replacement function according to a preferred embodiment of the present invention.
2 is a block diagram of the monitoring device of FIG.
3A is a waveform graph of a power supply voltage and a resistance load in a steady state, and FIG. 3B is a waveform graph of a power supply voltage and a resistance load in a poor contact state.
4a to 4f is a fuzzy rule table applied to the present invention.
5 is an explanatory diagram for explaining that the contact failure of a particular position is determined by the multi-faceted evaluation method in the present invention.
Figure 6 is a configuration diagram of an embodiment of the neutral wire protection device of Figure 1;
FIG. 7 is a diagram illustrating an embodiment of the disconnection detector of FIG. 6. FIG.
8 is an embodiment of the neutral line protector of FIG.

Hereinafter, described in detail with reference to the accompanying drawings a preferred embodiment of the present invention. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

1 is a circuit diagram of a photovoltaic power generation system having a monitoring and neutral wire replacement function according to a preferred embodiment of the present invention, the solar cell module 100, the junction box 200, the power converter 300, the monitoring device 400 ), The neutral protection device 500 and the KEPCO system 600.

The solar cell module array 100 converts solar energy into electrical energy and outputs the same. A plurality of solar cell modules 101 to 108 are installed in an array form.

The junction box 200 is a part that combines and outputs the electrical energy converted by the plurality of solar cell modules 101 to 108. Such a junction box 200 is provided with a fuse and a diode in one solar cell module line. The main circuit breaker (MCCB) is provided at the end when combining and outputting the electrical energy output from each solar cell module, and various sensors such as a horizontal plane solar radiation meter, an inclined plane solar radiation meter, a solar cell surface temperature sensor, and an outside temperature sensor The sensor box 210 is provided to receive a signal of the signal processing, and to control the inverter 310 in the power converter 300 based on the signal.

The power converter 300 receives electrical energy output through the junction box 200 through the power line 10 and converts the electrical energy into AC power. In the power converter 300, a main circuit breaker (MCCB) is provided at a front end thereof, and an inverter 310 for converting DC power into AC power is provided at a rear end thereof, and a magnetic switch MC is provided at a rear end of the inverter 310. Is provided, the rear end of the magnetic switch (MC) is provided with a main breaker (MCCB) again.

Such a configuration is provided in a general photovoltaic power generation system, and the present invention adds the monitoring device 400 and the neutral conductor replacement device 500 to the general photovoltaic power generation system as described above, thereby preventing contact failure at a specific position. It monitors and acts as a protective device in case of neutral break.

The monitoring device 400 monitors a poor contact for each line in the junction box 200, a poor contact of a power line between the junction box 200 and the inverter 310, and a contact failure in the power converter 300. If it is determined that the contact is bad, the alarm and at the same time transmits the warning information to the manager terminal, and remotely controls the power breaker according to the control command transmitted from the manager terminal.

As shown in FIG. 2, the monitoring apparatus 400 includes a power converter 410 for detecting and digitizing a power state value of a specific location in real time; Converts the digital data into basic element information for determining power quality, generates power state data, calculates and extracts power quality based on the power state data, and analyzes the amount of change for each extracted power quality element. If a certain amount or more is converted, the result is applied by applying a fuzzy rule table for the change amount, and the result of the extracted fuzzy rule table is applied to a multi-faceted evaluation method to determine contact failure at a specific position, and to generate an alarm in case of contact failure. A controller 420 for controlling the transmission of alarm information to the manager terminal and controlling the power breaker according to a power cut control command transmitted remotely; An alarm generator 430 for generating an alarm for contact failure in association with the controller; The communication module 440 performs transmission of the alarm information in cooperation with the controller, and receives a remote control command transmitted through wired / wireless communication from a remote location and transmits the remote control command to the controller.

Neutral wire replacement device 500 is provided between the power converter 300 and the electric field system 600, the phase of the three-phase four-wire (R, S, T, N) supply power input to the electric field system 600 When the phase detection is detected, it is determined that the disconnection of the neutral wire and the load connected to the single-phase power is replaced by replacing the neutral wire.

As shown in FIG. 6, the neutral wire replacement device 500 includes a disconnection detector 510 for detecting whether the neutral wire is disconnected; A controller 520 for determining whether the wire is disconnected based on the disconnection detection value output by the disconnection detector 510 and generating a control signal for replacing the neutral wire when the wire is disconnected; A neutral line protector (530) for maintaining the balance of the single-phase voltage by replacing the disconnected neutral line according to a control signal generated by the controller (520); An alarm generator 540 for alarming the disconnection of the neutral wire according to the alarm generation control signal output by the controller 520; And an alarm release signal input unit 550 for generating an alarm release signal and transmitting the generated alarm release signal to the controller 520 when the alarm release switch for the alarm release is operated by the administrator after the alarm is generated by the alarm generator 540.

Here, the disconnection detector 510 may include: a phase detector 511 which detects a phase signal for each phase of input power as shown in FIG. 7; If the level of any one of the phases R, S, T detected by the phase detector 511 is maintained at a high level for a predetermined time or more includes an image determination determiner 512 to determine that the image and output the image detection detection value; It is preferable.

In addition, the neutral protector 530, the switch (M1) for connecting the three phases (R, S, T); It includes coils (L1 ~ L3) for maintaining the balance of the single-phase voltage by connecting the three-phase and the neutral neutral (N).

The photovoltaic power generation system equipped with a monitoring and neutral line replacement function according to the present invention configured as described above converts solar energy into electrical energy in a plurality of solar cell modules 101 to 108 provided in the solar cell module array 10. The converted electrical energy is passed through each line consisting of a plurality of fuses (F1 ~ F8) and a plurality of diodes (D1 ~ D8) in the junction box 200 is combined into one main breaker (MCCB) It is output to the power line 10 through.

The DC power output to the power line 10 is transmitted to the power converter 300, is converted into AC power through the inverter 310 in the power converter 300, and sequentially through the magnetic switch (MC), the main circuit breaker (MCCB) The electric field system 600 is transmitted. Here, the KEPCO system 600 is provided with a conventional LV panel, a distribution board, a circuit breaker, and the like, and supplies solar power and KEPCO power to the load.

In the photovoltaic power generation system operating as described above, the present invention detects contact failure for each specific position in the monitoring apparatus 400. In the present invention, a specific position is set as a line connected with each solar cell module in the junction box 200, an arbitrary position of the power line 10, and a power input terminal in the power converter 300. It will be apparent to those skilled in the art that this particular location may vary depending on the user or system designer.

The power converter 410 of the monitoring device 400 detects and digitizes a power state value of a specific location in real time and transmits the same to the controller 420.

The controller 420 converts the digital data into basic element information for determining power quality, generates power state data, calculates and extracts power quality based on the power state data, and extracts each power quality element. When the change amount is analyzed and converted to a predetermined amount or more, the result is obtained by applying the fuzzy rule table for the change amount, and the result of the extracted fuzzy rule table is applied to the multi-faceted evaluation method to determine the contact failure at a specific position. Alarm generation control and transmission of alarm information to the administrator terminal are controlled.

For example, the controller 420 converts the digital data into basic element information for determining power quality to generate power state data. Here, the basic element information for determining the power quality includes power factor, harmonic occurrence, overcurrent, surge, disconnection, swell, etc., and calculates the basic element quality based on the current and voltage detected for each phase. Since the method to be used applies the method used by a well-known power measuring method as it is, detailed description is abbreviate | omitted.

Next, the contact failure detection algorithm built in advance is executed to detect the electrical contact failure of the neutral wire. Here, the contact failure detection algorithm calculates and extracts power quality based on the power state data and the waveform in the steady state stored for each element, and analyzes the amount of change by the extracted power quality elements to change the fuzzy for the amount of change when a predetermined amount is changed. The rule table is applied to detect contact failure.

Here, the amount of change in power quality for each element is determined to be a change in power quality even if a change in quality occurs for any one of a plurality of power quality.

3A is a graph illustrating waveforms of power supply voltage and resistance load when no contact failure occurs, and FIG. 3B is a graph illustrating waveforms of power supply voltage and resistance load when contact failure occurs.

Therefore, the voltage / current waveform in the abnormal state and the voltage / current waveform at the time of contact failure are different. Therefore, when the voltage / current waveform is used, it is easy to know whether the power quality is changed. One of the easiest ways to determine the change in power quality of each element is to compare the power quality of each element of the previous state and the power quality of each element of the current state to determine whether the power quality has changed.

Next, if there is no change in power quality or a change in power quality occurs, but the amount of change is very small, it is judged to be in a normal state.In contrast, a change in power quality has occurred, and the amount of change is determined to be normal. In case of exceeding the criteria, the judgment is made as an abnormal state, and the fuzzy rule table for the amount of change is applied.

) 및 전압 THDE(

)의 출현 여부, 검출전압과 아크 판단의 기준이 되는 전류 임계치(

) 및 전류 THDE(

)의 출현 여부, 전압 임계치와 전압 THDE와의 상관관계, 전류 임계치와 전류 THDE와의 상관관례를 고려하여 퍼지 룰 테이블을 구현하였다.4A and 4F illustrate an example of a fuzzy rule table applied to the present invention. Here, ZO is set to 1, PS is set to 2, PM is set to 4, and PB is set to 6, and the voltage threshold value of the harmonics which is the reference for detecting voltage (V) and arc judgment (

) And voltage THDE (

), The current threshold that is the basis for the detection voltage and arc judgment (

) And current THDE (

Fuzzy rule table is implemented in consideration of the presence of), correlation between voltage threshold and voltage THDE, and correlation between current threshold and current THDE.

The result value is calculated by substituting the amount of change for each element detected into the fuzzy rule table implemented as described above, and the result of the acquired value is determined using the multi-faceted evaluation method as shown in FIG.

Here, the multi-faceted evaluation method does not judge contact failure when six result values (I, II, III, IV, V, VI) are in the hexagon represented by 10. Instead, six result values are shown in FIG. If it is out of the hexagon represented by 10, it is determined as a poor contact. Referring to FIG. 5, if the value of V is larger than the other values, or the values of IV, V, VI are normal, and the values of I, II, and III exceed the reference values, it is determined as a poor contact. It is shown.

As a result of the primary determination by a well-known method, if it is determined that the contact is poor, it is checked whether the contact lasts for a predetermined period of time calculated in advance in order to determine the electrical contact failure for reliability. This is because the load does not occur when the electrical contact failure occurs momentarily and then returns to the normal state, so that an instantaneous contact failure does not generate an alarm. Here, in the present invention, it is judged whether or not the electrical contact failure for a certain period of time (duration time), it is also possible to determine the final electrical contact failure by using the repeated number of arcs generated in addition to this method.

After the final determination of the electrical contact failure, the controller 220 operates the alarm generator 430 to generate an alarm for contact failure. Here, although not shown in the figure, by displaying the position where the contact failure occurred using the indicator, the administrator can easily know the location where the contact failure occurred. The location where contact failure occurs can be easily identified by assigning a unique number or separate identification information for each location.

On the other hand, the controller 420 generates the alarm information including the location information where the contact failure occurred when the alarm for the contact failure, search the information of the pre-built manager terminal and delivers the information of the manager terminal and the alarm information to the communication module Thus, through the communication module 440, the alarm information can be quickly transmitted to a management server or an administrator terminal located remotely.

The remotely located manager receives the above alarm information through the management server or the manager terminal, and sends a power control command to block the main breaker remotely. The remote control command thus transmitted is received through the communication module 440 and transmitted to the controller 420, and the controller 420 automatically operates the main breaker according to the remote control command, thereby causing an accident due to a poor contact. Will be prevented.

On the other hand, as another feature of the present invention, when the AC power converted by the inverter 310 is transmitted to the KEPCO 600, it is possible to detect the disconnection of the neutral wire, the protective action during the detection of the disconnection of the neutral wire, such as overvoltage or abnormal voltage This prevents accidents that damage the load due to voltage unbalance.

For example, in order to prevent such an accident in advance in the present invention, the neutral wire replacement device 500 always detects the state of the neutral wire, and when the disconnection of the neutral wire is detected, an immediate alarm is performed and the other neutral wire is replaced at the same time. It compensates and prevents overvoltage from flowing to the light load side.

In more detail, when AC power is supplied by the inverter 310, the disconnection detector 510 operates to detect whether the neutral line N is disconnected, and the controller 520 detects the detected disconnection detection value. To pass). For example, the phase detector 511 of the disconnection detector 510 detects phase signals of R, S, and T phases of three-phase electric power input in real time, and is detected by the phase detector 511 in the phase determining unit 512. Check whether one of the phase signals of each phase is maintained for a predetermined time or more in order to determine the imaging at a high level. It is determined that the phase is missing, and the disconnection detection value is transmitted to the controller 520. Here, when the neutral wire is disconnected, any phase level becomes a high level.

Here, the disconnection detection value outputs a high signal (5V) when an imaging is detected, and outputs a low signal (0V) when an imaging is not detected.

The controller 520 analyzes the disconnection detection value provided from the disconnection detector 510 by using a built-in control program, and when it is determined that the disconnection is not the neutral disconnection, the neutral protector 530 does not operate. In this case, the neutral line protector 530 is operated.

The neutral line protector 530 has a neutral line internally, and when an operation control signal is transmitted by the controller 520, the switch M1 operates to connect three phases R, S, and T. The replacement neutral wire (N) and the coil (L1 ~ L3) for each phase is connected. In other words, the replacement neutral wire (N) is replaced with the neutral wire disconnected by connecting the three phases to the replacement neutral wire when the neutral wire is disconnected in the state that is always present. Here, the neutral wire connection can be easily connected by using a magnet switch or the like.

When the neutral line protector 530 operates to replace the disconnected neutral line, the unbalance of single phase voltages for each phase which may be caused by the neutral line disconnection may be maintained in an equilibrium state as before, and thus, the electric field system of the power converter 300 may be maintained. Even if the neutral wire of the power supplied to the 600 is disconnected, the problem that the overvoltage flows to the light load side and burns out the electric device as in the prior art.

On the other hand, the controller 520 is to drive the alarm generator 540 immediately when it is determined that the disconnection of the neutral wire as known. The alarm generator 540 is driven to alert the disconnection of the neutral wire, in the present invention is to alarm by using a visual alarm and / or an audio alarm method.

If the administrator recognizes this in the presence of a visual or auditory alarm, he / she will follow up promptly, thereby preventing various accidents that may occur due to disconnection of the neutral line.

In addition, the administrator can release the alarms as needed. For example, when the alarm release switch provided in the alarm release signal input unit 550 is operated, the alarm release signal input unit 550 generates an alarm release signal and transmits it to the controller 520.

When the alarm releasing signal is transmitted, the controller 520 stops the operation of the alarm generator 540 to release the alarm.

In addition, the present invention, after performing the alarm for the disconnection of the neutral wire, if the alarm is not requested to be released within a predetermined time period automatically cuts off the power (single phase power) supplied to the load, the accident that may occur due to the neutral disconnection This is prevented in advance.

In addition, the present invention is to detect the neutral disconnection through the disconnection detector 510 in the state in which the neutral protector 530 is operated by the neutral disconnection, wherein the neutral protector 530 due to the neutral disconnection Even if the voltage unbalance is detected, the controller 520 automatically operates the main breaker, cuts off the single-phase load power, or simultaneously cuts off the main breaker and the single-phase load power, thereby preventing the load device from being burned out. Done.

That is, according to the present invention, in the photovoltaic power generation system, when the neutral wire of the power supplied from the power converter is disconnected automatically performs automatic switching to the preliminary neutral wire to prevent phase voltage unbalance caused by the disconnection of the neutral wire Therefore, the electric load on the light load side is prevented from being burned out. In addition, if a neutral wire break occurs, an alarm is generated immediately so that the manager can recognize it, and afterwards, the manager can quickly take follow-up actions, thereby preventing an accident such as a system failure that may occur later due to the wire break. will be.

In addition, since contact failure can be detected for each specific position, it is easy to check the location of the failure point, thereby saving maintenance time and effort. In addition, by performing a warning on a poor contact, it is possible to prevent an accident from occurring due to a poor contact.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

100... Solar Module Array
200 ... Junction
300 ... Power converter
400 ... monitor
500... Neutral wire replacement device
510... Disconnection detector
520... Controller
530... Neutral line protector
540... Alarm generator
550... Alarm release signal input section

Claims (6)

delete delete A solar cell module array for converting and outputting solar energy into electrical energy;
A junction box for coupling and outputting the electrical energy converted by the solar cell module array;
A power converter receiving electrical energy output through the junction box through a power line and converting the electrical energy into AC power;
Monitoring contact failures of each line in the junction box, failure of power line contact between the junction box and the inverter, and contact failure in the power converter, and if it is determined that the contact failure is performed, an alarm is performed and alert information is transmitted to the manager terminal. A monitoring device controlling a power breaker in accordance with a control command transmitted from the manager terminal remotely;
It is provided between the power converter and the KEPCO system, detects the phase of the three-phase four-wire (R, S, T, N) supply power input to the KEPCO system, and if the phase detection is detected it is determined to be a neutral disconnection and the neutral wire It includes a neutral wire replacement device for replacing the load connected to the single-phase power to prevent burnout,
The neutral wire replacement device,
A disconnection detector for detecting whether the neutral line is disconnected;
A controller for judging disconnection using the disconnection detection value output by the disconnection detector, and generating a control signal for replacing the neutral when disconnection;
And a neutral line protector which maintains a single phase voltage balance by replacing the neutral line of the power line supplied to the KEPCO system according to the control signal generated by the controller.
The method according to claim 3, wherein the disconnection detector,
A phase detector for detecting phase signals of R, S, and T phases;
The sun provided with a supervision and neutral line replacement function characterized in that it comprises an image determination determiner to determine the phase if the level of any one of the phases R, S, T detected by the phase detector to a high level for a predetermined time or more. Photovoltaic power generation system.
The method according to claim 3, The neutral protective group,
A switch for connecting three phases (R, S, T);
The solar power generation system with a supervisor and neutral wire replacement function comprising a coil for connecting the three-phase and the neutral neutral wire (N) to maintain the balance of the single-phase voltage.
The method of claim 3, wherein the neutral wire replacement device,
An alarm generator for alarming the disconnection of the neutral wire according to the alarm generation control signal output by the controller;
Monitoring and neutral line replacement function further comprises an alarm release signal input unit for generating an alarm release signal and delivers to the controller when the alarm release switch for the alarm release is operated by the administrator after the alarm is generated by the alarm generator; The solar power generation system provided.

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