KR20030057236A - Digital multi-function meter for load management based on remote meter reading and method of controlling the same - Google Patents

Abstract

PURPOSE: A digital multi function accumulation power meter system for remote load management and a control method thereof are provided, which accumulate usage power of a house and also perform power metering and load management and voltage management unitedly. CONSTITUTION: An analog signal preprocessing part(31) detects an effective value and power factor angle of voltage and current by receiving secondary voltage and current deformed from the primary voltage and current through a metering voltage transformer(16) and a metering current transformer(14). A synchronization input part(32) inputs analog signals of the power factor angle and the effective values of the voltage and the current detected in the analog signal preprocessing part. An analog digital converter part(33) converts the analog signals of the power factor angle and the effective values of the voltage and the current being output from the synchronization input part. A multiplexer(34) outputs selectively the digital signal of the power factor angle and the effective values of the voltage and the current being output through the analog digital converter part. A micro controller(35) receives the digital signals of the power factor angle and the effective values of the voltage and the current through the multiplexer, and performs remote load management according to the requirement of a remote load management system(20) by accumulating the usage power on the basis of the digital signals. A communication part(37) accesses a micro controller through the remote load management system and a communication network. A memory stores data for the accumulation of the usage power and the remote load management. and a power supply circuit(38) provides an operation power by rectifying the secondary voltage of the metering voltage transformer.

Description

DIGITAL MULTI-FUNCTION METER FOR LOAD MANAGEMENT BASED ON REMOTE METER READING AND METHOD OF CONTROLLING THE SAME}

The present invention relates to an integrated power meter, specifically, a digital multi-function integrated power meter that integrates and automatically manages load management tasks for general users, such as metering, load management, and voltage management, by using a remote load management system and a communication network. And a control method thereof.

With the development of the electric, electronic and telecommunication industries, consumer products and manufacturers' equipment are becoming more and more high performance. Nuclear families, dual incomes, and increased number of outings have led consumers to demand automatic meter reading, high reliability and high quality power supply. have.

Traditionally, meter reading has been done by the meter readers visiting the general public and visually confirming the readings of the mechanical wattmeter. This is uncomfortable for the general public for various reasons, and efforts have been made to improve it. As an example, there has been a simple digital method of digitizing only the speed count circuit using a light source, a rotating disk, and a light receiving element in a conventional mechanical integrated power meter. In addition, a digital method of calculating the amount of power used using voltage and current analog signals from an instrument current transformer and an instrument transformer using a microcontroller has been proposed. In fact, they are technically feasible enough in view of the recent rapid development of information and communication technology, but they are delayed due to economic problems because all mechanical integrated wattmeters of existing customers must be changed or replaced with new digital wattmeters.

On the other hand, in view of high reliability and high quality power supply, general consumers are drawn from secondary substations and are supplied with power from distribution lines having a structure that is widely distributed and arranged using a dendritic structure. These tracks have a short range of kilometers to tens of kilometers since they are routed through mountainous, coastal, and urban dense areas where the general population is distributed. In particular, since these lines are directly exposed to various consumer areas and experience power failure or low voltage problems for various reasons such as accidents, fires, new loads or relocations, and rapid increase in load, the reliability of the power supply to the general consumer is Of course, the power quality is seriously degraded.

In order to resolve the complaints of ordinary consumers due to these problems, the electric power company sets internal management goals such as power failure management, loss management, load management, and voltage management for high-quality power supply. As a result, the results are embodied and applied to the field.

Specifically, in terms of power outage management, the distribution lines are designed in a multi-part structure to minimize the blackout period. Breakers are installed at the track outlets, and load switchgear is installed on or between tracks. They minimize the blackout section by separating the blackout section and attempting to load balance through accidental operation. However, since the switchgear work is all done by hand, there is a time lag when a worker goes to the operation point of the switchgear on the downtown and long-distance tracks in case of a power failure, and a long time outage occurs, resulting in considerable complaints.

However, in recent years, electric power companies have been actively promoting the development of distribution automation system that can remotely control switchgear on the line in collaboration with academia, industry and research institute. It is known that it is succeeding in reducing.

Loss management is an effort to reduce production costs from the utility side. Minimize line loss by determining switch operating point on line that can minimize line loss through simulation at regular period or when new line is established. This problem can be solved through a multi-segment multi-stage structure attempted in terms of power outage management and a distribution automation system that can remotely control the switchgear on these lines.

In terms of voltage management, voltage management is generally an effort to keep the voltage supplied to the general consumer within an appropriate voltage range. The main transformer of the distribution system is controlled through ULTC, and the column transformer is controlled through a tap change, so that the voltage supplied to the customer is kept constant as the load changes. However, efforts to keep the supply voltage within an appropriate range have been made difficult due to the track's positiveness, the diversity of the customer's load type, the establishment or relocation of the customer, the natural increase in the load, and the seasonal change.

Accordingly, voltage measurement sites are selected at regular intervals, the voltages are measured for a given period, and the recording voltages are reviewed to identify ineligible measurement sites where the voltage exceeds the upper and lower limit voltage limits. Based on these results, efforts are made to improve the voltage ratio. Here, the voltage titration rate represents the percentage of the titration measurement point with respect to the total measurement points. The actual voltage management should be performed by a person in charge who selects a voltage measuring point for several dozen lines and installs and collects a voltage recorder at the measuring point within a few weeks. In general, the measurement point for voltage management is directly under the periphery, but directly below and at the end of the 5% dropout point.

By the way, distribution lines range from a few kilometers to tens of kilometers and not only pass through the city center, but also the construction of the tracks is changing frequently. Therefore, it is very difficult to accurately select a voltage measurement point in a short time and to check the root of the measurement point. In particular, the problem of installing and collecting a voltage recorder on the site due to long distances, congestion, and going out of the consumer requires enormous time and effort, and the measurement results are difficult to guarantee the accuracy. This issue is an important complaint to the general public and can be freely and reasonably selected without any limitations on the number of measurement points, and is based on innovative remote management techniques that can minimize measurement and analysis time and ensure its accuracy. It can be solved through management techniques.

Next, we will look at the load management aspects. Load management is divided into high pressure load management and low pressure load management, and is closely related to both customers and utilities. In the case of load management, new customers are frequently created and natural increase or change of load is severe. In particular, low-voltage load management has a larger number of customers to manage than high-pressure load management, and in reality, it is impossible to control the loads of these customers. Doing.

However, because the number of valves on the distribution line reaches thousands, it is impossible to accurately manage the load by measuring the load of the column transformers at regular intervals or whenever a new customer is requested. Therefore, after the overload anticipated transformer is decided through the computer operation or monthly operation, the target transformer is dispatched to the field to decide the replacement of the actual transformer or the relocation of the load. It is virtually impossible to accurately determine the expected overload transformer because the calculation of the maximum demand power based on the rate or inequality rate is also inaccurate. As a result, many transformers are damaged and power failures occur in summer. This problem can be solved through the innovative management method based on the remote management method that can minimize the measurement and analysis time and secure the accuracy of the load pattern by the general customer or the unit.

As described above, in order to meet the demands of the general consumer, it is possible to improve the economics of the remote metering which can minimize the inconvenience of the consumer, and to control the load without limiting the number of measurement points or the number of load management points and the number of times of implementation. There is an urgent need for new load management techniques based on remote management techniques that can improve the quality of supply power by collecting voltage management data remotely and accurately. In other words, a digital multifunctional integrated power meter is required to measure the power consumption of a general consumer as a basic function and to expand the low voltage load management data and voltage management data measurement and recording function.

Accordingly, an object of the present invention is proposed to solve the above-mentioned problems, and the digital multi-function multiplication for remote load management that integrates the amount of power used by the general electric consumer, and can be used in combination with meter reading, load management, and voltage management. It is to provide a power meter and a control method thereof.

1 is a block diagram showing a circuit configuration of a digital multifunction integrated power meter according to a preferred embodiment of the present invention;

2 and 3 are flowcharts showing different embodiments of the control procedure of the microcontroller of FIG. 1;

4 is a view for explaining a measurement point for the general voltage management;

5 is a graph showing an example of inappropriate points exceeding an upper limit voltage;

6 is a graph showing an example of inappropriate points exceeding the lower limit voltage;

7 is a view showing an example in the case of including a transformer directly under the current load measurement site;

FIG. 8 is a graph illustrating an example of a current load change pattern of a time-phase transformer in FIG. 7;

9 is a view showing a case where a current load measurement site does not include a transformer directly below; And

FIG. 10 is a view illustrating a general acceptor current load pattern for each time zone in FIG. 9.

* Description of the symbols for the main parts of the drawings *

10: customer inlet 12: customer load

14: Instrument current transformer 16: Instrument transformer

20: Remote load management system 30: Digital multifunction integrated power meter

According to one aspect of the present invention for achieving the object of the present invention as described above, the digital multifunction integrating power meter: the secondary voltage and current modified from the primary side voltage and current through the instrument transformer, instrument current transformer An analog signal preprocessing unit which receives and detects an effective value and a power factor angle of voltage and current; A synchronization input unit for synchronously inputting an analog signal having an effective value and a power factor of the voltage and current detected by the analog signal preprocessor; An analog-digital converter for converting an analog signal of an effective value and a power factor of the voltage and current output through the synchronous input unit into a digital signal and outputting the digital signal; A multiplexer for selectively outputting a digital signal of an effective value and a power factor of the voltage and current output through the analog-digital converter; A microcontroller receiving a digital signal of an effective value of a voltage and a current and a power factor angle through the multiplexer, integrating the amount of power used based on the multiplexer, and performing remote load management according to a request of a remote load management system at a remote location; A communication unit for remotely connecting the microcontroller through a remote load management system and a communication network; A memory for temporarily storing data for integration of power consumption and remote load management; And a power supply circuit rectifying the secondary voltage of the instrument transformer to provide an operating power source.

In a preferred embodiment of the present invention, the microcontroller has an integrated power mode and a load management mode, the load management mode is executed at the request of the remote load management system and proceeds based on a scheduler provided by the remote load management system. .

In a preferred embodiment of the present invention, the analog signal preprocessor comprises: a voltage rms detection unit for detecting an effective value of the secondary side voltage and current deformed from the primary side voltage and current through an instrument transformer and an instrument current transformer; 1 current rms detection unit; A power line current measuring unit for directly measuring a primary current of an instrument current transformer; A second current effective value detector which receives a current measured by the power line current measuring unit and detects a current effective value; And a power factor angle detector for detecting a power factor angle of the secondary side voltage and current modified from the primary side voltage and current through the instrument transformer and the instrument current transformer.

In a preferred embodiment of the present invention, a battery is provided that provides a minimum power supply to a necessary portion of a circuit so that data of a memory is preserved for a predetermined period during a power failure.

According to another aspect of the invention, the control method of the digital multi-function integrated power meter includes: setting an operation mode of the digital multi-function integrated power meter to the integrated power mode; Accumulating and storing the amount of power used; Determining whether an interrupt for changing an operation mode has been received from the remote load management system; Changing an operation mode to a load management mode when an interrupt for changing the operation mode is received; Detecting and storing load management data including time-phase voltage patterns and time-phase load current patterns based on a scheduler provided by the remote load management system; When the storage of the load management data is completed, switching from the load management mode to the integrated power mode; And transmitting integrated load management data including power consumption data, time-phase voltage pattern, and time-phase current pattern in response to the data transmission request interrupt of the remote load management system.

In a preferred embodiment of the present invention, when the interrupt is received according to the load current transmission request for each measurement location from the remote load management system includes the step of reading the load current data in real time and transmitting the data to the remote load management system.

According to another aspect of the invention, the control method of the digital multi-function integrated power meter includes: starting the digital multi-function integrated power meter in a reference integrated management mode, and changing the load management scheduler as necessary; Accumulating and storing the amount of power used; Determining whether an interrupt has been received from the remote load management system; Initializing data for load management based on a scheduler and initialization data provided from a remote load management system when a data reception request interrupt is received; Detecting and storing integrated load management data including power consumption data, time period voltage pattern, and time period current pattern based on the scheduler; And transmitting the stored integrated load management data to the remote load management system when the data transmission request interrupt is received.

In a preferred embodiment of the present invention, when the interrupt is received according to the load current transmission request for each measurement location from the remote load management system includes the step of reading the load current data in real time and transmitting the data to the remote load management system.

Embodiments of the present invention may be modified in various forms and should not be construed that the scope of the present invention is limited to the embodiments described below. This embodiment is provided to more clearly explain the present invention to those skilled in the art.

(Example)

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a circuit configuration of a digital multifunction integrated power meter according to a preferred embodiment of the present invention.

Referring to the drawings, the digital multi-function integrated power meter 30 (hereinafter, abbreviated as integrated power meter) is installed directly under the inlet (or transformer) 10 of a general electric customer, so that the instrument transformer 16 and the instrument current transformer 14 are installed. Receives an input signal for voltage and current, respectively, and performs integrated power processing, and any one of a wired or wireless communication network including a remote load management system 20 and a power line, a dedicated line, or a wireless communication method provided at a remote location. Connected for remote meter reading and load management.

The remote load management system 20 builds data collected remotely from the integrated power meter 30 in a remote place in its own database and automates the meter reading, and in particular, uses load current data for a certain time period and voltage data for a certain time period. By automating the load management and voltage management tasks, it greatly improves the economics and improves the quality of the supply voltage for general customers compared to the conventional remote metering system.

The integrated power meter 30 is largely composed of an analog signal preprocessor 31, a synchronous input unit 32, an analog-digital converter 33, a multiplexer 34, a microcontroller 35, a ROM 36a, a RAM 36b, The communication unit 37 includes a power supply circuit 38 and a battery 39. The analog signal preprocessor 31 includes a voltage effective value detector 31a, a first current effective value detector 31b, a second current effective value detector 31c, a power factor angle detector 31d, and a power line current measurer 31e. It consists of. The synchronization input unit 32 is composed of a plurality of synchronization input circuits 32a, 32b, 32c, 32d, and the analog-to-digital conversion unit 33 is composed of a plurality of analog to digital converters 33a, 33b, 33c, 33d.

The voltage effective value detector 31a is connected to the multiplexer 34 through the first synchronous input circuit 32a and the first analog-digital converter 33a. The first current effective value detector 31b is connected to the multiplexer 34 through the second synchronous input circuit 32b and the first analog-digital converter 33b. The power line current measuring unit 31c obtains a direct current value from the power line not passing through the current transformer 14 and inputs it to the second current rms detecting unit 31c. The second current effective value detector 31c is connected to the multiplexer 34 through the third synchronous input circuit 32c and the third analog to digital converter 33c. The power factor angle detector 31d is connected to the multiplexer 34 through a fourth synchronous input circuit 32d and a fourth analog digital converter 33d.

Each analog signal pre-processed by the analog signal preprocessor 31 is input to the analog-digital converter 33 through the synchronization input unit 32 to be converted into a digital signal, and selectively to the microcontroller 35 through the multiplexer 34. Is entered. The analog signal preprocessor 31 minimizes the computational load of the microcontroller 35 so that the microcontroller 35 can accurately and effectively handle data processing for integrated load management such as power consumption, time-phase voltage, and current patterns. do.

The microcontroller 35 performs data processing and control for the control of the overall operation of the integrated power meter 30 and for integration and integrated load management. In the ROM 36a, firmware which is a control program of an integrated power meter to be executed by the microcontroller 35 is stored, and data processed in the control process is stored in the RAM 36b. The communication unit 37 is a wired or wireless communication device and is connected to a remote remote load management system 20 through a communication network, and performs data transmission and reception according to integrated power and load management.

The power supply circuit 38 rectifies the modified voltage provided from the transformer 16 to provide the overall operating power of the totalizer 30. The battery 39 is designed to provide a minimum power supply to the necessary portion of the circuit so that the data in the RAM 36b is preserved for a period of time during a power failure.

Next, the operation of the integrated power meter of the present invention having the above configuration will be described in detail.

The integrated power meter 30 is a secondary side voltage e ₂ and a current i ₂ deformed from the primary side voltage e ₁ and the current i ₁ through the instrument transformer 16 and the instrument current transformer 14. Is received through the analog signal preprocessor 31. The integrated power meter 30 operates in the integrated power mode and the load management mode. The signal processing procedure in each mode will be described.

In the signal processing process for the integrated power, the voltage rms detecting unit 31a and the first current rms detecting unit 31b of the analog signal preprocessor 31 each of the secondary side voltage e ₂ and current i ₂ , respectively. Rms (e ₂ ) and rms (i ₂ ) are obtained and the result is input to the first and second analog-to-digital converters 33a and 33b through the first and second synchronization input circuits 32a and 32b, respectively. do. The power factor angle detector 31d calculates a phase difference, that is, the power factor angle θ, between the secondary voltage e ₂ and the current i ₂ , and transmits the fourth analog to digital converter 33d through the fourth synchronization input circuit 32d. Enter If the direct current measurement is necessary, the direct current rms value rms (i ₁ ) is obtained by the second current rms value detector 31c, which is obtained through the third synchronous input circuit 32c. ) Is entered.

As described above, the analog signals input to the analog-digital converter 33 are converted into digital signals and selectively input to the microcontroller 35 through the multiplexer 34, thereby integrating the used power.

In the signal processing procedure for load management, as described above, the secondary voltage (e ₂ ) and the current (i ₂ ) of the secondary side voltage (e ₂ ) from the voltage effective value detector (31a) and the first current effective value detector (31b) for integrated power. The process of obtaining each rms rms (e ₂ ) and rms (i ₂ ) is the same, but the process of the microcontroller 35 for load management is different. Specifically, with reference to the accompanying drawings, Figures 2 and 3 will be described in detail below.

2 and 3 are flowcharts showing different embodiments of the control procedure of the microcontroller 35 of FIG.

First, referring to FIG. 2, when the operation of the integrated power meter 30 is started, in step S10, the used power amount W is set to an initial value W ₀ (W = W ₀ ) and the operating mode MODE is integrated power. Initialize to mode (MODE = 0). In step S11, it is checked whether an interrupt is received from the remote load management system 20 through the communication unit 37.

If no interrupt is received, the flow advances to step S12 to continuously accumulate the amount of power used (W). In the integration process, after holding the synchronization input unit 32 for data synchronization, voltage and current effective values rms (e ₂ ) and rms (i ₂ ) are obtained from the first and second analog-to-digital converters 33a and 33b. The power factor angle θ is obtained through the analog-digital converter 33d. The accumulated amount of used power W is accumulated in the RAM 36b. Integration is performed as in Equation 1 below. Where T _w is the sampling period.

[Equation 1]

In step S13, the current operation mode is determined. When the operation mode MODE is the integrated power mode MODE = 1, the control repeatedly proceeds to step S12 to perform the process of accumulating the used power amount.

On the other hand, if an interrupt is received in step S11, the flow advances to step S14 to switch the operation mode MODE to the load management mode MODE = 1 and determine the type of interrupt in step S15. Interrupts include load management mode switch request interrupt (INT_0) and integrated load management data transmission request interrupt (INT_1).

When the load management mode switch request interrupt INT_0 is received, control proceeds to step S16 in which an initial value required for the load management mode, for example, a measurement time interval T according to the scheduler of the remote load management system 20, The daily measurement number n and the measurement day m are initialized, and the flow proceeds to step S12. As described above, after the integration of the used power amount W is made in step S12, the current operation mode MODE is determined in step S13.

If the operation mode MODE is the load management mode MODE = 1, control proceeds to step S17. During the measurement time interval T given in step S17, the effective values of voltage and current are incremented. That is, the microcontroller 35 performs the rms voltage rms (e ₂ ) and rms current rms (i ₂ ) from the first and second analog-to-digital converters 33a and 33b through the multiplexer 34 during the measurement time interval T. Obtain the voltage and the current and store it in the RAM 36b.

Control then proceeds to step S18 to check the measurement time interval T. In the case of an error, control repeats to step S11, and if normal, to step S19. In step S19, an average of time-phase voltages and currents is calculated and stored in the RAM 36b. This average value is obtained by dividing the voltage and current obtained in step S17 by the number of samplings during the measurement time interval T.

In step S20, it is determined whether the number of repetitions has been completed in accordance with the scheduler condition (n × m). If incomplete, control proceeds to step S11 to calculate voltage and current averages for the next time interval. If completed, the control proceeds to step S21 to switch the operation mode from the load management mode (MODE = 1) to the integrated power mode (MODE = 0), initialize the data in the memory RAM 36b, and proceed to step S11 to integrate the integrated power. Operate in mode.

Again, after switching to the load management mode (MODE = 1) in step S14, in the case of interrupt type determination result data transmission request interrupt (INT_1) in step S15, control proceeds to step S22.

The data transmission request interrupt is divided into the integrated load management data transmission request and the load current transmission request by measurement point. In step S22, the corresponding data is transmitted to the remote load management system 20 according to the type of data transmission request interrupt. For example, when the integrated load management data transmission request is required, the power consumption data, the time-phase voltage pattern, the inappropriate voltage type and frequency, and the time-phase current pattern data are transmitted. On the other hand, in the case of a load current transmission request for each measurement point, the load current data is read in real time and the data is transmitted to the remote load management system 20.

Next, a control procedure by the microcontroller 35 according to another embodiment will be described with reference to FIG. 3. In this other embodiment, the microcontroller 35 controls the integrated power meter 30 without separate operation mode classification as in the above-described embodiment.

Referring to the drawing, in step S30, the integrated power meter is started in the reference integrated management mode, and if necessary, the load management scheduler is changed externally, and the computer power meter 30 is initialized based on the external setting. In this case, the reference integrated management mode means that integrated power and load management data are collectively recorded by a load management scheduler that is set at the beginning. In step S31, it is checked whether the interrupt is received from the remote load management system 20 through the communication unit 37. The interrupt is divided into a data reception request interrupt (INT_R) and a data transmission request interrupt (INT_T). If an interrupt is received, control proceeds to step S32 to determine the interrupt type.

When the data reception request interrupt INT_R is received, control proceeds to step S33 to initialize data for load management based on the scheduler and the initialization data provided from the remote load management system 20. For example, the measurement time interval T, the daily measurement number n, and the measurement date m according to the scheduler of the remote load management system 20 are initialized, respectively.

Subsequently, in step S34, the amount of used power W is continuously accumulated, and this process corresponds to step S12 of the above-described embodiment. During the measurement time interval T given in step S35, the effective values of voltage and current are respectively incremented. Increment here means adding the voltage or current values obtained in the current step to the values recorded in the previous step, respectively. The flow advances to step S36 to check the measurement time interval T. If not measured during the measurement time interval (N), control proceeds to step S31 repeatedly, and if measured (Y), the control proceeds to step S37. In step S37, an average of time-phase voltages and currents is calculated and stored in the RAM 36b. In step S38, it is determined whether the number of repetitions has been completed in accordance with the scheduler condition (n x m). If incomplete, control proceeds to step S31 to calculate the voltage and current averages for the next time interval. After completion, control proceeds to step S39 to initialize the backup memory area data in the memory RAM 36b to switch to the used memory area, switch the used memory area to the backup memory area, and then proceed to step S31. The above control steps S35 to S39 correspond to the above steps S17 to S21 of this embodiment, respectively.

Again, in the case of an interrupt type determination result data transmission request interrupt (INT_T) in step S32, control proceeds to step S40. The data transmission request interrupt is divided into the integrated load management data transmission request and the load current transmission request by measurement point. In step S40, the corresponding data in the backup memory area is transmitted to the remote load management system 20 according to the type of the data transmission request interrupt. For example, when the integrated load management data transmission request is required, the power consumption data, the time-phase voltage pattern, the inappropriate voltage type and frequency, and the time-phase current pattern data are transmitted. On the other hand, in the case of a load current transmission request for each measurement point, the load current data is read in real time and the data is transmitted to the remote load management system 20.

According to the integrated power meter 30 of the present invention, the remote load management system 20 is remotely and accurately through the communication with the integrated power meter 30 installed in a remote place, as well as low-voltage load management data, Since various data can be collected for load management such as voltage management data, integrated remote load management such as power meter reading, load management, and voltage management is possible.

Next, various application examples in which the digital multifunction integrated power meter of the present invention is applied to the consumer will be described with reference to FIGS. 4 to 10.

4 is a view for explaining a measurement point for the general voltage management.

Referring to the drawings, in general, the measuring point for voltage management is the direct customer 42, 45 and the terminal customer of the transformer 41, 44 of one of the periphery of the periphery pressure 40, but within the 5% voltage drop point. It is located at (43, 46). At this time, an example of the average voltage recording data format for voltage management recorded by the multifunction digital integrated power meter of the present invention is shown in Table 1 below.

TABLE 1

Average voltage record data format

When the upper limit voltage and the lower limit voltage are exceeded, the equations are represented by Equations 2 and 3, respectively. Where i is the recording date and j is the recording order number, which is determined based on the load management schedule. Here, the maximum recording date is represented by n and the maximum recording frequency per day is m, and the number of occurrences of exceeding the upper limit voltage (V _ulimit ) and the lower limit voltage (V _Limit ), which are inadequate voltage types, are recorded. The unit is malt (V).

[Equation 2]

In case of exceeding the upper limit voltage

[Equation 3]

In case of lower voltage limit exceeded

The above upper and lower limit voltages are illustrated in the accompanying drawings in FIGS. 5 and 6.

FIG. 5 is a graph showing an example of an inappropriate point exceeding the upper limit voltage, and FIG. 6 is a graph showing an example of an inappropriate point exceeding the lower limit voltage. 3 shows that the number of inadequacies exceeding the upper limit voltage V _Ulimit is three times. On the contrary, in FIG. 4, the lower limit voltage V _Llimit is exceeded, indicating that the number of inappropriate times is two. In general, the graph shown in FIG. 5 is the voltage pattern seen in the direct water, and the graph shown in FIG. 6 is the voltage pattern shown in the terminal customer.

When the digital multi-function integrated power meter of the present invention is installed in a general consumer, the measurement location of the periphery voltage but 5% voltage drop point as well as the low voltage consumer distributed in a wide range can be freely set by the measurement location. By verifying and reinforcing inadequate voltage points accurately and quickly, the quality of the voltage can be effectively improved to meet the needs of the general consumer. Such an inappropriate voltage count recording function may be implemented in an integrated power meter or a remote load management system.

Next, the case where the measurement point for load management is assumed to be a pole transformer or all general customers belonging to it will be described. FIG. 7 is a diagram illustrating an example in which a current load measurement location includes a transformer directly below, and FIG. 8 is a graph illustrating an example of a current load variation pattern of the transformer according to the time slot of FIG. 7.

In the figure, reference numeral 50 denotes a columnar transformer and outputs a line voltage of 22.9 KV. Reference numeral 51 denotes the position of the voltage measurement point immediately below the margin. And reference numeral 52 is a consumer load. The format of the effective value average current data for load management is similar to that of Table 1 above, and is represented as shown in Table 2 below. Where the unit is amperes (A).

TABLE 2

Average load current record data format

At this time, the maximum load current is stored, which may be represented by Equation 4 below, and the overload predicted transformer may be a case where Equation 4 satisfies Equation 5 below. Where TI _n is obtained as P / V _n and TI _m is the allowable current. V _n is the transformer supply voltage.

[Equation 4]

[Equation 5]

Referring to this case in more detail with reference to Figure 8, if the overload is expected in the columnar transformer 50 can be solved through load relocation or transformer capacity expansion. If the load control for the customer is possible, the overload problem may be solved by performing the load control on the overload columnar transformer 50 while monitoring the load current data in real time through the digital multifunction power meter of the present invention.

Next, a case in which the current load measurement site does not include a transformer directly below will be described with reference to FIGS. 9 and 10. FIG. 9 is a view illustrating a case in which a current load measurement location does not include a transformer directly, and FIG. 10 is a view illustrating a general acceptor current load pattern according to time zones in FIG. 9.

With reference to the drawings, in this case, the measurement points shall be taken as the measurement sites, not including directly under the transformer as measurement points. It is very convenient in terms of management because it uses only the digital multifunction integrated power meter of the present invention installed in general audiences without including a separate measuring place directly below the toilet.

In this case, as shown in Equation 6 below, the load current pattern for each customer belonging to the transformer should be summed to obtain a new transformer load pattern.

[Equation 6]

Where I _ij denotes the load current value of the j-th customer for the i-th time zone, and k means the maximum number of customers belonging to the transformer. This process will be described in more detail with reference to FIG. 10. In the drawing, reference numeral 60 denotes a transformer load current pattern, and reference numerals 61 to 63 denote respective current load patterns of three consumers.

Referring to the drawings, when three consumers are included in the columnar transformer 50, the load pattern for each time zone of the transformer 50 is obtained by adding load currents of three customers for each time zone. In addition, the synthesized peak power applied to the columnar transformer 50 can be obtained by applying the result obtained through Equation 7 to Equation 4. Equation 5 can identify the overload and the expected overload transformer.

[Equation 7]

In addition, when the load control for the customer is possible, the real-time load current data is collected using the digital multi-function integrated power meter of the present invention, whether the overload is confirmed through Equation 7, and the load control is performed on the overload columnar transformer 50. By doing so, the overload problem can be solved. Where I _t represents the load on the transformer at time t.

As described above, an embodiment of a configuration of a digital multifunction integrated power meter for remote management of the present invention and a method of controlling the same have been described with reference to the accompanying drawings, which are merely described as an example and do not depart from the spirit of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made therein.

According to the present invention as described above, through the communication between the remote load management system and the digital multi-function integrated power meter, it is possible to collect the power consumption data, as well as low voltage load management data, voltage management data from the remote control accurately and quickly Integrated remote load management, including load management and voltage management. Therefore, compared to the conventional remote metering system based on the amount of power used can greatly improve the economics.

In addition, it is possible to collect voltage management data accurately and quickly remotely without being constrained by the voltage measuring point or the number of times of implementation, thereby minimizing the voltage management cost and significantly improving the quality of the voltage supplied to the general consumer. In the case of low-voltage load management, it is possible to accurately measure thousands of displacement loads instead of simple calculation methods such as acceptance rate and inequality rate, and to calculate accurate maximum demand power. The quality of power can be greatly improved.

In this way, the integrated remote load management by the digital multi-function integrated power meter is possible, which can greatly improve the economics of the remote meter reading and maximize the quality of the power supplied. In addition, by enabling automatic meter reading, economic and technical effects can be obtained in the electric power-related industry, and integrated metering (electricity, gas, and water) can be realized by securing application technology of the metering industry.

Claims (8)

An analog signal preprocessor for receiving the secondary voltage and current modified from the primary voltage and current through an instrument transformer and an instrument current transformer to detect an effective value and a power factor angle of the voltage and current; A synchronization input unit for synchronously inputting an analog signal having an effective value and a power factor of the voltage and current detected by the analog signal preprocessor; An analog-digital converter for converting an analog signal of an effective value and a power factor of the voltage and current output through the synchronous input unit into a digital signal and outputting the digital signal; A multiplexer for selectively outputting a digital signal of an effective value and a power factor of voltage and current output through an analog-digital converter; A microcontroller configured to receive a digital signal of an effective value of a voltage and a current and a power factor angle through the multiplexer, accumulate the amount of power used, and perform remote load management according to a request of a remote load management system at a remote location; A communication unit for remotely connecting the microcontroller through a remote load management system and a communication network; A memory for temporarily storing data for integration of power consumption and remote load management; Digital multi-function integrated power meter for remote load management including a power supply circuit rectifying the secondary voltage of the transformer for the instrument to provide operating power. The method of claim 1, The microcontroller has an integrated power mode and a load management mode, the load management mode is executed at the request of the remote load management system and proceeds based on the scheduler provided by the remote load management system. The method of claim 1, The analog signal preprocessor A voltage RMS value detector and a first current RMS value detector for detecting an RMS value of the secondary voltage and current deformed from the primary voltage and current through an instrument transformer and an instrument current transformer; A power line current measuring unit for directly measuring a primary current of an instrument current transformer; A second current effective value detector which receives a current measured by the power line current measuring unit and detects a current effective value; Digital multifunction integrated power meter including a power factor angle detector for detecting the power factor angle of the secondary side voltage and current modified from the primary side voltage and current through the instrument transformer, the instrument current transformer. The method of claim 1, A digital multifunction integrated power meter that includes a battery that provides a minimum amount of power to the required portion of the circuit so that data in the memory is retained for a period of time during a power failure. In the control method of the digital multi-function integrated power meter of claim 2: Setting an operation mode of the digital multifunction integrated power meter to the integrated power mode; Accumulating and storing the amount of power used; Determining whether an interrupt for changing an operation mode has been received from the remote load management system; Changing an operation mode to a load management mode when an interrupt for changing the operation mode is received; Detecting and storing load management data including time-phase voltage patterns and time-phase load current patterns based on a scheduler provided by the remote load management system; When the storage of the load management data is completed, switching from the load management mode to the integrated power mode; And transmitting integrated load management data including power consumption data, time-phase voltage pattern, and time-phase current pattern in response to a data transmission request interrupt of the remote load management system. . The method of claim 5, The method of controlling a digital multi-function integrated power meter, comprising: reading the load current data in real time and transmitting the data to the remote load management system when an interrupt is received according to the load current transmission request for each measurement point from the remote load management system. . In the control method of the digital multi-function integrated power meter of claim 1: Starting the digital multifunction integrated power meter in a reference integrated management mode and changing a load management scheduler as necessary; Accumulating and storing the amount of power used; Determining whether an interrupt has been received from the remote load management system; Initializing data for load management based on a scheduler and initialization data provided from a remote load management system when a data reception request interrupt is received; Detecting and storing integrated load management data including power consumption data, time period voltage pattern, and time period current pattern based on the scheduler; And transmitting the stored integrated load management data to the remote load management system when a data transmission request interrupt is received. The method of claim 7, wherein The method of controlling a digital multi-function integrated power meter, comprising: reading the load current data in real time and transmitting the data to the remote load management system when an interrupt is received according to the load current transmission request for each measurement point from the remote load management system. .