KR20240124890A - Replacement auxiliary device having output section - Google Patents

Abstract

In the event of a power outage or low voltage in a distribution network due to a failure or other reasons, a replacement auxiliary device is disclosed which can automatically block the generated power from flowing into the distribution network by opening a switch of a power generation facility for the safety of the line. The replacement auxiliary device is characterized by including a sensing unit which is connected to a connection point A and senses current for the consumption current used by a customer and the generated power of a distributed power source, and a controller which calculates the consumed power and the generated power using the sensed current and turns off a switch installed on the primary side of a transformer to be replaced when a no-interruption condition is reached.

Description

Replacement auxiliary device having an output section{.}

The present invention relates to a technology for replacing an uninterruptible transformer, and relates to a replacement auxiliary device having an output section.

Power generated from various distributed power sources such as solar and wind power is converted into the same power as the distribution network through internal devices and connected. In the case of solar power generation, direct current is generated from solar panels, which is converted into alternating current through an inverter and connected by matching the frequency and phase with the distribution network.

Normally, if the current generated power is 100 kW, customers consume 80 kW of this generated power and the remaining 20 kW is converted to high voltage and supplied to other transformers connected to high voltage lines or to high voltage customers.

In this state, if the power of the high-voltage line is cut off, the solar panel must supply voltage to not only its own customers in the same low-voltage network but also other transformers instead of the high-voltage line, and since it cannot handle this, a low voltage occurs momentarily at the connection point and the reverse voltage prevention device also operates.

That is, as soon as the high voltage of the distribution is cut off, a low voltage occurs at a specific connection point, and thus the power generation of the solar panel is also cut off, thereby performing the purpose of the reverse pressure prevention device, which is to “cut off the distributed power source power in conjunction with the distribution grid to protect the facility in the event of a failure.”

However, when individual transformers lose their original functions due to fuse blowing, transformer failure, work-related needs, etc. during normal operation of the distribution high-voltage transformer, the operation of the reverse pressure prevention device varies depending on the situation.

In general, if distributed power sources are not separated from the downed power lines, electric shock and fire can occur due to generated power even if the protection device of the distribution network automatically cuts off the power. Therefore, the reverse pressure prevention device prevents electric shock and fire.

In addition, if a certain section is forcibly blacked out and the worker is judged to be in a diagonal state and continues to work while power is supplied from the distributed power source, there is a very high risk of the worker being electrocuted. Therefore, a reverse pressure prevention device is used to prevent the worker from being electrocuted.

In addition, if the total load of the section that was out of power is 1000KW and the power generation capacity of the connected distributed power source is 100KW, the distributed power source will not be able to handle the load and will cause a breakdown. Therefore, a reverse pressure prevention device is used to protect the distributed power source equipment.

Whether or not the distributed power supply is shut off when the transformer function is lost is as follows.

1) When the customer's consumption load is greater than the generated power: Low voltage occurs => generated power is cut off.

2) When the customer's consumption load is less than the generated power: Normal voltage => Customer load is supplied with generated power.

In the above situation 2), the "uninterruptible transformer replacement" method can be simply performed without connecting a separate device to repair the transformer. However, since there is currently no separate method, method, or procedure, a separate uninterruptible device must be installed to implement uninterruptible power in the situation, which requires a lot of work time and high costs.

In addition, when the distributed power source is separated from the line during diagonal work, there is a problem that the power generation company suffers losses during that time because the meter is not read even though it is in a generating state.

1. Republic of Korea Patent Registration No. 10-0769583 (Registration Date: October 17, 2007)

The present invention has been proposed to solve the problems according to the above background technology, and the purpose of the present invention is to provide a replacement auxiliary device using a distributed power source and a replacement method for an uninterruptible transformer, which can automatically block the generated power from flowing into the distribution network by opening the switch of a power generation facility for the safety of the line when a power outage or low voltage occurs in the distribution network due to a failure or other reasons.

In addition, another purpose of the present invention is to provide a replacement auxiliary device using a distributed power source that implements an accurate work procedure for each situation when replacing an uninterruptible transformer, and a method for replacing an uninterruptible transformer.

In addition, the present invention has another purpose of providing a replacement auxiliary device using a distributed power source and a replacement method for an uninterruptible power transformer, which can perform an uninterruptible power supply using a distributed power source when the generated power exceeds the consumed power and execute a work sequence accordingly.

In order to achieve the task presented above, the present invention provides a replacement auxiliary device that can automatically block the flow of generated power into the distribution network by opening a switch of a power generation facility for the safety of the line when a power outage or low voltage occurs in the distribution network due to a failure or other reasons.

The above replacement auxiliary device is,

A sensing unit connected to connection point A to sense current for consumption current used by customers and generated power of distributed power sources; and

It is characterized by including a controller that calculates the consumed power and the generated power using the sensed current, and turns off a switch installed on the primary side of the transformer to be replaced when a no-interruption condition is reached.

In addition, the replacement auxiliary device is characterized by including a communication unit that receives environmental information on the current location of the distributed power source from an external server.

In addition, the controller is characterized in that it first calculates a work setting time zone using the environmental information, and after the work setting time zone is reached, if the no-interruption condition is satisfied, it turns off the switch.

In addition, the above-mentioned non-interruption condition is characterized by a state in which the consumed power is less than the generated power.

In addition, the environmental information is characterized by including the maximum generation time of the distributed power source, the minimum usage time zone of the power consumption, and current weather information.

In addition, the replacement auxiliary device is characterized by including an output section that indicates whether the switch is off or on.

In addition, the switch is characterized in that it is turned off after the secondary side lowering line of the transformer to be replaced is disconnected from the connection point A to prevent sparking.

In addition, the switch is turned on when the transformer is replaced with a new transformer, and after turning on, the secondary side step-down line of the new transformer is connected to the connection point A.

On the other hand, the present invention provides a method for replacing an uninterruptible transformer using a distributed power source, characterized in that it comprises the steps of: (a) a step in which a replacement auxiliary device is connected to a switch and connection point A installed on the primary side of a transformer to be replaced; (b) a step in which the replacement auxiliary device checks a non-interruptible condition at the connection point A; (c) a step in which the replacement auxiliary device turns off the switch when the non-interruptible condition is satisfied; and (d) a step in which the replacement auxiliary device turns on the switch when the replacement of the transformer is completed.

In addition, the step (b) is characterized by including a step of receiving environmental information on the current location of the distributed power source from an external server through a communication unit.

In addition, the step (c) is characterized by including a step in which the controller first calculates a work setting time zone using the environmental information; and a step in which, after reaching the work setting time zone, the switch is turned off if the no-interruption condition is satisfied.

According to the present invention, when replacing a transformer connected to a large-scale power generation facility installed in a mountainous area or farmland and a customer consuming relatively little power, i.e. a transformer whose power generation capacity exceeds its power consumption, the uninterruptible transformer can be replaced using the power generation facility.

In addition, another effect of the present invention is that the uninterruptible power method can be implemented without separate cost by using the power generation facility as an external power source for the uninterruptible power method.

In addition, another effect of the present invention is that comprehensive worker safety, such as inspection and grounding, can be ensured by clearly distinguishing between diagonal work and uninterrupted work and clearly defining the procedures for them separately, thereby ensuring worker safety.

In addition, another effect of the present invention is that the power generation cost can be preserved by the amount of power used by using the generated power as a connected consumption load.

Figure 1 is a conceptual diagram of a typical power system.
Figure 2 is a replacement auxiliary device according to one embodiment of the present invention.
FIG. 3 is a flow chart showing a process for replacing an uninterruptible transformer using a distributed power source according to one embodiment of the present invention.

The present invention can have various modifications and various embodiments, and specific embodiments are illustrated in the drawings and specifically described in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

When describing each drawing, similar reference numerals are used to refer to similar components.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only to distinguish one component from another.

For example, without departing from the scope of the present invention, the first component could be referred to as the second component, and similarly, the second component could also be referred to as the first component. The term "and/or" includes any combination of a plurality of related listed items or any item among a plurality of related listed items.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless expressly defined in this application.

Hereinafter, with reference to the attached drawings, a replacement auxiliary device and an uninterruptible transformer replacement method using a distributed power source according to one embodiment of the present invention will be described in detail.

Fig. 1 is a conceptual diagram of a general power system (100). Referring to Fig. 1, in a power system (100), DC (Direct Current) power generated by a distributed power source (110) is converted into AC (Alternating Current) power through an inverter (120) and supplied to a main power line (101). Typically, a transformer (150) is installed on a power pole (140), and the primary side of the transformer (150) is connected to a high-voltage power line (160), and the secondary side of the transformer (150) is connected to a low-voltage power line (170) to supply the transformed power. The low-voltage power line (170) is connected to customer A (181) and customer B (182) to supply low power. The distributed power source (110) may be solar power generation by solar panels, wind power generation by wind power, etc.

In addition, a first switch (121) is placed between the inverter (120) and connection point A. The first switch (121) is opened to automatically block the generated power from flowing into the distribution network in order to ensure the safety of the line when a power outage or low voltage occurs in the distribution network due to a failure or other reasons.

The first switch (121) is an electronic switch, and a power relay is used, but is not limited thereto, and semiconductor switching elements such as a FET (Field Effect Transistor), a MOSFET (Metal Oxide Semiconductor FET), an IGBT (Insulated Gate Bipolar Mode Transistor), a power rectifier diode, a thyristor, a GTO (Gate Turn-Off) thyristor, a TRIAC (Triode for alternating current), an SCR (Silicon Controlled Rectifier), an I.C (Integrated Circuit) circuit, etc. can be used.

In particular, for semiconductor devices, bipolar and power MOSFET (Metal Oxide Silicon Field Effect Transistor) devices can be used. Power MOSFET devices have a DMOS (Double-Diffused Metal Oxide Semiconductor) structure, unlike general MOSFETs, due to high-voltage and high-current operation.

Of course, the first switch (121) may be connected to the replacement auxiliary device (130) or may be connected to a low voltage sensor (not shown) that is separately connected to connection point A. In addition, the switch (121) may include a driving circuit (not shown) that operates the switch (121).

A second switch (190) is installed between the high-voltage line (160) and the primary side of the transformer (150). The second switch (190) may be an electronic switch, a cut-out switch (COS: Cut Out Switch), etc.

To replace the transformer (150), the user connects the replacement auxiliary device (130) to connection point A, the first switch (121), the second switch (190), etc.

Connection point A is an electrical connection point with the same voltage, frequency, and phase to which the power generated from the solar panels, the power generated from the transformer, and the power used by the customer are all connected.

FIG. 2 is a replacement auxiliary device (130) according to an embodiment of the present invention. Referring to FIG. 2, the replacement auxiliary device (130) may be configured to include a sensing unit (210) that is connected to a connection point A and senses current for consumption current used by customers (181, 182) and generation power of a distributed power source (110), a controller (220) that calculates consumption power and generation power using the sensed current and calculates a work setting time zone using environmental information about the current location and turns off the second switch (190), a communication unit (230) that receives environmental information from a weather server (not shown), and an output unit (240) that displays consumption power, generation power, work setting time zone, and off operation status.

The sensing unit (211) may be composed of a current sensor (211) and a voltage sensor (212). Accordingly, the current or voltage is sensed to calculate the generated power and consumed power at connection point A. In particular, the sensing unit (211) is also connected to the secondary side of the transformer (150).

The controller (220) may be configured to include a calculation unit (221) that calculates power consumption and power generation using the sensed current, an analysis unit (222) that compares the power consumption and power generation to determine whether a transformer replacement condition is satisfied, and a driving unit (223) that turns off the second switch (190) if the power outage condition is satisfied.

In addition, the analysis unit (222) calculates the work setting time zone by using the environmental information about the current location for the transformer replacement condition, and turns off the second switch (190) when the calculated work setting time zone is reached. Of course, the work setting time zone can also be output through the output unit (240). In this case, the user can check it and perform the work.

The driving unit (223) generates an on/off signal for driving, thereby turning the second switch (190) on/off.

The calculation unit (221) and the analysis unit (222) refer to units that process at least one function or operation, and may be implemented as software and/or hardware. In the hardware implementation, it may be implemented as an ASIC (application specific integrated circuit), a DSP (digital signal processing), a PLD (programmable logic device), an FPGA (field programmable gate array), a processor, a microprocessor, other electronic units, or a combination thereof designed to perform the above-described function. In the software implementation, it may include software configuration components (elements), object-oriented software configuration components, class configuration components, and task configuration components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, data, databases, data structures, tables, arrays, and variables. The software, data, etc. may be stored in a memory and executed by a processor. The memory or the processor may employ various means well known to those skilled in the art.

The communication unit (230) performs a function of receiving environmental information on the current location of the distributed power source (110) from a weather server and a power management server (not shown). If so, it is less costly to replace the transformer (150) during the continuous maximum power generation time of solar power generation, etc., and the minimum power consumption time. Therefore, the replacement time of the transformer (150) is determined using the environmental information on the location of the transformer (150). The environmental information may also include current weather information. In other words, it is efficient to replace the transformer when the weather is clear or the wind speed is at a certain level.

Accordingly, the communication unit (230) is connected to a weather server and a power management server through a communication network (not shown) and may be configured to include a communication modem, a microprocessor, etc.

The communication network (not shown) refers to a connection structure that enables information exchange between each node, such as a plurality of terminals and servers, and may be a public switched telephone network (PSTN), a public switched data network (PSDN), an integrated services digital network (ISDN), a broadband ISDN (BISDN), a local area network (LAN), a metropolitan area network (MAN), a wide area network (WLAN: Wide LAN), etc. However, the present invention is not limited thereto, and may be a wireless communication network such as CDMA (Code Division Multiple Access), WCDMA (Wideband Code Division Multiple Access), Wibro (Wireless Broadband), WiFi (Wireless Fidelity), HSDPA (High Speed Downlink Packet Access) network, Bluetooth, NFC (Near Field Communication) network, satellite broadcasting network, analog broadcasting network, DMB (Digital Multimedia Broadcasting) network, etc. Or, it may be a combination of these wired communication networks and wireless communication networks.

The output unit (240) may be an LCD (Liquid Crystal Display), an LED (Light Emitting Diode) display, an OLED (Organic LED) display, a touch screen, a flexible display, etc. In the case of a touch screen, it may also be used as an input means. In addition, the output unit (240) may include a sound system and may output information as a voice.

The connection between the replacement auxiliary device (130) and the field equipment can be mainly made using the tongs method, but other methods are also possible.

Figure 3 is a flow chart showing the process of replacing an uninterruptible transformer using a distributed power source according to one embodiment of the present invention. First, since only a three-phase transformer is possible in a three-phase power generation facility, the transformer supply method and the power generation method are examined first. That is, uninterruptible replacement of a three-phase transformer is not possible in a single-phase distributed power source.

The target is a location where the power generation capacity is less than the sum of the power consumption, and this can be checked and judged by a computer system built on a power management server. In addition, it is necessary to judge the workable time. That is, in order for actual work to be possible with a contracted power and power generation capacity, the actual power generation must be greater than the actual power consumption, and the appropriate work time can be selected by the developed hourly load detection system. For example, the continuous maximum power generation time of solar power generation and the minimum use time of power consumption can be checked and judged by a computer system. Of course, the above-described preliminary review contents can be installed and performed on-site by installing a replacement auxiliary device (130).

Select the maximum power generation time zone (step S310). That is, the work setting time zone with the maximum power generation time is calculated using environmental information. In other words, this is the process of selecting a time zone where the power generation capacity is continuously greater than the power consumption. It is most advantageous to select a clear day where maximum power generation can be maintained continuously.

After that, the current is measured (step S320). That is, the non-interruption condition [consumption current < output current of the power plant] in the actual field is confirmed. When the hook-on meter for current measurement measures the distributed power source and has a positive value, and when the secondary step-down current of the transformer is measured in the same measurement direction and has a positive value, it can be known that the distributed power source is flowing into the transformer, and this satisfies the non-interruption condition because the generated power of the distributed power source is greater than the consumed power.

In addition, if necessary, the above conditions can be created for some customers through a power outage agreement and customer-side short-term contracts. If the above verification step is deemed unfeasible, the existing method is selected or work is postponed.

Afterwards, the secondary step-down line, which is the low-voltage output of the transformer (150), is separated, and the switch (190) is opened (steps S330 and S340). After the switch (190) is opened, a spark may occur when the secondary step-down line is separated. This is due to the exciting current of the transformer (150). Even if the switch (190) is opened while the secondary step-down line is connected, a high voltage is induced on the primary side of the transformer (150), and this may cause a risk of electric shock to the user. Therefore, the switch (190) is opened after the secondary step-down line is separated.

Afterwards, the transformer to be replaced is removed from the transformer hanger and the new transformer is installed on the pole (140) (step S350).

After that, the switch (190) is turned on (i.e., closed), and the secondary side lowering line is connected (step S360). In other words, if the secondary side lowering line is connected before the switch (190) is turned on, a spark occurs when connected. This is caused by the excitation current of the transformer. Therefore, after the switch (19) is turned on, the secondary side lowering line is connected. After that, the work is completed by measuring the upper limit of the secondary side lowering line and connecting it to confirm the normal state.

In addition, the steps of the method or algorithm described in connection with the embodiments disclosed herein may be implemented in the form of program instructions that can be executed by various computer means, such as a microprocessor, a processor, a CPU (Central Processing Unit), and the like, and recorded on a computer-readable medium. The computer-readable medium may include program (instruction) codes, data files, data structures, etc., alone or in combination.

The program (command) code recorded on the above medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium may include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs, DVDs, and Blu-rays, and semiconductor memory devices specially configured to store and execute program (command) codes such as ROMs (Read Only Memory), RAMs (Random Access Memory), and flash memories.

Here, examples of program (instruction) code include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc. The above-mentioned hardware device can be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

100: Power System
110: Distributed Power
120: Inverter 121: 1st switch
130: Replacement Auxiliary Device 140: Electric Pole
150: Transformer 160: High voltage line
170: Low voltage line 190: Second switch
210: Sensing section
211: Current sensor 212: Voltage sensor
220: Controller 221: Calculator
222: Analysis section 223: Drive section
230: Communication section 240: Output section

Claims (1)

A sensing unit (210) connected to connection point A to sense current for power consumption used by customers (181, 182) and power generation of a distributed power source (110); and
It includes a controller (220) that calculates the power consumption and the power generation by using the sensed current, and turns off the switch (190) installed on the primary side of the transformer (150) to be replaced when the no-interruption condition is reached.
The above connection point A is an electrical connection point with the same voltage, frequency and phase to which distributed power, power generated from a transformer and power used by customers are all connected.
The transformer (150) to be replaced above corresponds to a location where the power generation capacity that can be checked and judged from a computer system is less than the sum of the power consumption.
It includes a communication unit (230) that receives environmental information about the current location of the distributed power source (110) from an external server;
The above controller (220) first calculates the work setting time zone using the above environmental information,
The above uninterrupted condition is a state in which the consumed power is less than the generated power,
The above environmental information includes the maximum power generation time zone of the distributed power source (110), the minimum usage time zone of the power consumption, and current weather information.
The above maximum power generation time period is the time period when power generation capacity is continuously greater than power consumption.
The above switch (190) is turned on when the above transformer (150) is replaced with a new transformer, and after turning on, the secondary side lowering line of the above new transformer is connected to the connection point A.
A replacement auxiliary device having an output section, characterized by including an output section (240) that indicates whether the switch (190) is off or on.