KR20240114411A - Auxiliary sensor supported synchro phasor measurement unit and data transmission method using the synchro phasor measurement unit - Google Patents

Abstract

The present invention relates to a synchronous phasor measurement device and a data transmission method using the same, which includes a phase-locked oscillator that generates a pulse signal in synchronization with the 1pps (1 pulse per second) signal of a GPS receiver, a voltage signal generated in the power system, and Current signal and measurement environment A sensor unit that measures surrounding environmental information and load power, and an A/D that converts the analog signal output from the sensor unit into a digital signal using the pulse signal output from the phase-locked oscillator as an operation signal. A voltage phasor and a current phasor are calculated from a converter and a signal output from the A/D converter, and the power sensing information including the calculated voltage phasor and current phasor is transmitted through a communication unit at a set first transmission period, and the sensor The environmental information and load power detected by the unit may include a control unit that transmits and processes the environmental information and load power through the communication unit every second transmission cycle that is set to be longer than the first transmission cycle.

Description

External sensor supported synchro phasor measurement unit and data transmission method using the synchro phasor measurement unit}

The present invention relates to an external sensor-supported synchronous phasor measurement device and a data transmission method using the same. More specifically, in a synchronous phasor measurement environment of power, detection is performed by sensors other than electrical measurement elements such as voltage, current, phasor, and frequency. This relates to a synchronous phasor measurement device that can measure and transmit the same data and a data transmission method using the same.

The power system is a system that goes from power generation to consumption by connecting power plants, substations, and loads with transmission lines. The power generation system that generates power, the transmission system that transmits power generated from the power generation system, and the power supplied through the transmission system. It consists of a distribution system that distributes to consumers.

In this power system, demand and supply for generation and consumption of power must be stable, so power demand must be continuously monitored. In the early days, it was easy to monitor power demand in small-scale systems, but as power demand gradually increased due to industrial advancement and informatization, and as power generation using new and renewable energy increased, power facilities also became large-scale and complex, and were replaced by the artificial methods that have been performed so far. The limit to operating the system effectively has been reached.

Therefore, comprehensive automation of equipment for efficient performance of power system operation tasks is being promoted rapidly by applying computer-based information collection, processing, analysis, and control functions and communication functions.

Examples of comprehensive facility automation methods include real-time voltage stability analysis methods and wide-area voltage stability evaluation methods. Real-time voltage stability analysis has been actively researched since the development of the synchronous phasor measurement unit (PMU).

A synchronous phasor measurement unit (PMU) is a device that is connected to a substation in the system and measures voltage and current in real time in the form of a phasor. Unlike existing measurement equipment, this synchronous phasor measurement device is very precisely time-synchronized through GPS and has a very short sampling period, allowing more information to be acquired more quickly. Domestic Public Patent No. 10-2009- It is described in No. 0028265 (published on March 18, 2009, PMU performing data compression transmission).

In the above published patents, synchronous phasor measurement units (PMUs) are synchronized by a synchronization signal transmitted from the outside, measure the voltage phasor of the facility bus bar and the current phasor of the connection line under a precise measurement time standard, and record the measured values. It is configured to transmit to a PDC (Phasor Data Concentrator) connected to the network.

In addition, the PDC receives voltage phasor and current phasor values transmitted from PMUs connected to the network and provides them to the wide area monitoring center, enabling measurement and monitoring of power in the transmission network.

Meanwhile, with the recent emergence of smart grids, microgrid power grids that are independent of the existing power grid using distributed power sources such as wind power and solar power and energy storage devices are being widely used in islands and remote areas at home and abroad, but they are prone to failures and have low Reliability requires frequent maintenance.

However, the existing synchronous phasor measurement unit (PMU) has the disadvantage of not being able to provide data that is correlated with environmental and weather data, such as solar power generation and wind power generation, which are renewable power generation sources, and household and industrial loads that use power. there is.

In addition, when acquiring data by installing a separate weather box, in the case of a data logger without a time synchronization device, time information from the final acquisition system must be used, resulting in a time error with the data acquired from the synchronous phasor measurement unit (PMU).

In addition, in order to transmit data directly to the PMU or PDC, an Ethernet communication method such as TCP/IP or UDP must be used, but most weather ship equipment adopts a serial-based data transmission method, so separate media converter equipment is required for long-distance transmission. This also has the disadvantage of lacking reliability in synchronization with the PMU that collects voltage and current data using GPS time synchronization because time delays occur during the data processing and transmission process.

Home and industrial loads use power supply passively, but in order to promote active measures such as plans to save energy through load reduction or demand response (DR), the usage status of power-using devices and facilities is monitored. needs to be monitored.

On the other hand, it is possible to consider a method of transmitting the voltage phasor and current phasor along with surrounding environmental information from a synchronous phasor measurement unit (PMU) to the load, but in this case, weather and current phasors do not change relatively rapidly over time. There is a need for a method to improve data transmission efficiency by considering the characteristics of environmental information.

The problem to be solved by the present invention to solve the above problems is a synchronous phasor measurement device that can provide time-synchronized data with voltage and current phasor information and information measured by a separate external sensor, and data transmission using the same. It provides a method.

In particular, the present invention efficiently transmits weather environment information with a relatively small change rate over time, and provides an expanded synchronous phasor measurement that enables load reduction and demand response (DR) based on nonintrusive load monitoring (NILM). The purpose is to provide a device and a method of transmitting its data.

A synchronous phasor measurement device according to one aspect of the present invention for solving the above technical problems includes a phase-locked oscillator that generates a pulse signal in synchronization with the 1pps (1 pulse per second) signal of the GPS receiver, and A sensor unit that measures the generated voltage signal, current signal, environmental information around the measurement environment, and load power, and the pulse signal output from the phase-locked oscillator is used as an operation signal, and the analog signal output from the sensor unit is converted into a digital signal. A voltage phasor and a current phasor are calculated from a converting A/D converter and a signal output from the A/D converter, and the power sensing information including the calculated voltage phasor and current phasor is transmitted through the communication unit at a first transmission period set for the power sensing information. It may include a control unit that transmits and processes the environmental information and load power detected by the sensor unit through the communication unit every second transmission cycle that is set to be longer than the first transmission cycle.

In an embodiment of the present invention, the environmental information and load power transmitted every second transmission cycle may not be transmitted if they are the same as the previous information.

In an embodiment of the present invention, the environmental information may be at least one of temperature, humidity, wind direction, wind speed, solar radiation, cloudiness, and fine dust amount.

A data transmission method using a synchronous phasor measurement device according to another aspect of the present invention is a data transmission method using the synchronous phasor measurement device, comprising the steps of a) determining whether the first transmission period set in the control unit has reached, and b) the first transmission period. When the transmission cycle has arrived, transmitting power sensing information through the communication unit; c) determining whether the second transmission cycle set in the control unit has reached; d) when the second transmission cycle has arrived; current environmental information and load power information; It may include the step of determining whether the environmental information and load power information of the previous state are the same, and e) transmitting the currently detected environmental information and load power information only if the determination result of step d) is not the same. .

In an embodiment of the present invention, the second transmission period may be an integer multiple of the first transmission period.

In an embodiment of the present invention, the second transmission cycle can be changed by the user through the control panel.

The present invention can provide power sensing information including voltage and current phasors as well as weather information and precise power load as data in time synchronization, enabling energy-independent power grid or microgrid and building EMS (BEMS) and factory EMS (FEMS) operations. provides advantages to

1 is a block diagram of a synchronous phasor measurement device according to a preferred embodiment of the present invention.
FIG. 2 is a flowchart showing a processing process for data transmission of the synchronous phasor measurement device of FIG. 1.

In order to fully understand the configuration and effects of the present invention, preferred embodiments of the present invention will be described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various changes can be made. However, the description of this embodiment is provided to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the present invention of the scope of the invention. In the attached drawings, components are shown enlarged in size for convenience of explanation, and the proportions of each component may be exaggerated or reduced.

Terms such as 'first' and 'second' may be used to describe various components, but the components should not be limited by the above terms. The above terms may be used only for the purpose of distinguishing one component from another. For example, a 'first component' may be named a 'second component' without departing from the scope of the present invention, and similarly, a 'second component' may also be named a 'first component'. You can. Additionally, singular expressions include plural expressions, unless the context clearly dictates otherwise. Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted as meanings commonly known to those skilled in the art.

Hereinafter, a synchronous phasor measurement device and a data transmission method using the same according to an embodiment of the present invention will be described in detail with reference to the drawings.

1 is a block diagram of a synchronous phasor measurement device supporting external sensing information transmission according to a preferred embodiment of the present invention.

Referring to Figure 1, the synchronous phasor measurement unit (PMU: Phasor Measurement Unit, 100) supporting external sensing information transmission according to the present invention includes a GPS receiver (110), a phase-locked oscillator (120), and a sensor. It is configured to include a unit 130, a noise filter 140, an A/D converter 150, a control unit 160, an operation unit 163, a storage unit 165, and a communication unit 170.

The GPS receiver 110 receives GPS signals including coordinates and time from GPS satellites, and outputs time data corresponding to world standard time and a 1pps (Pulse Per Second) signal once every second.

The phase-locked oscillator 120 receives a 1pps signal output every second from the GPS receiver 110 and generates a pulse signal.

The sensor unit 130 measures voltage signals and current signals generated in the power system and weather information around the measurement environment.

The sensor unit 130 may include a voltage measurement sensor 131, a current measurement sensor 133, and an external information measurement sensor 135, and may include more various sensors as needed.

The voltage measurement sensor 131 measures the voltage generated in the power system, and the current measurement sensor 133 measures the current generated in the power system.

As an example, the voltage measurement sensor 131 can measure a three-phase bus voltage, and the current measurement sensor 133 can measure the current of a three-phase transmission line (T/L) or transformer current.

The external information measurement sensor 135 may be a sensor that measures at least one external information among temperature, humidity, wind direction, wind speed, solar radiation, cloud cover, and power load.

The noise filter 140 removes noise included in the analog signal, which is a detection signal output from the sensor unit 130, and outputs it.

The noise filter 140 is used to prevent aliasing that may occur when converting the analog voltage signal, current signal, and external environmental information of the power system measured by the sensor unit 130 into a digital signal. Filtering may be performed to remove signals in a high frequency band preset for current signals and external sensors.

The A/D converter 150 uses the pulse signal output from the phase-locked oscillator 120 as an operation signal (synchronization signal) and converts the analog signal output from the sensor unit 130 through the noise filter 140 into a digital signal. do.

The control unit 160 calculates a voltage phasor and a current phasor from the signal output from the A/D converter 150, and transmits power sensing information including the calculated voltage phasor and current phasor and external sensing information to the communication unit according to a set transmission method. It is processed to be transmitted to the destination communication address through (170).

Here, the control unit 160 performs calculations based on FFT (Fast Fourier Transform), which processes the digital signal output from the A/D converter 150 at high speed using a DFT (Discrete Fourier Transform) algorithm to obtain measurement data of voltage and current. can be calculated as a voltage phasor and a current phasor expressed in magnitude and phase angle.

In addition, power sensing information and external sensing information including the calculated voltage phasor and current phasor can be processed to be transmitted through the communication unit 170 according to a set transmission method along with time information.

Preferably, the control unit 160 transmits the calculated power sensing information including the voltage phasor and the current phasor to the destination communication address through the communication unit 170 at a set first transmission cycle.

In addition, the external sensing information is processed to be transmitted to the destination communication address through the communication unit 170 when transmission is determined according to the set transmission decision method every second transmission cycle that is longer than the first transmission cycle.

More preferably, the control unit 160 does not transmit the current information if the currently measured weather information in each second transmission cycle is the same as the previously transmitted external sensing information, and the currently measured sensing information in each second transmission cycle is not transmitted. If the value is different from the information transmitted, the current information can be transmitted.

FIG. 2 is a flowchart of a data transmission method using the synchronous phasor measurement device of FIG. 1.

Referring to FIG. 2, the control unit 160 determines whether the first transmission cycle has reached (S210), and when it is determined that the first transmission cycle has reached the current voltage calculated from the signal output from the A/D converter 150. The current sensing information of the external information measurement sensor 135, including the phasor and the current phasor, is transmitted and processed to be transmitted to the destination communication address through the communication unit 170 (S220).

At this time, data is transmitted to the PDC (Phasor Data Concentrator, 300) through the communication network 200, and the PDCs 300 transmit the collected data to the monitoring server 400, and the monitoring server 400 performs monitoring. enable it to be performed.

In addition, the control unit 160 determines whether the second transmission cycle is set to be longer than the first transmission cycle (S230), and when it is determined that the second transmission cycle has arrived, it determines whether the currently measured information is the same as the previously transmitted information. Determine (S240).

Previously transmitted information is assumed to be stored in the storage unit 165, and current information is also stored in the storage unit 165.

If the current information measured in step S240 is different from the previously transmitted information, the control unit 160 transmits the current information (S250).

In contrast, if the currently measured information in step 240 is the same as the previously transmitted information, the current information is not transmitted.

Preferably, the second transmission period may be set to an integer multiple of the first transmission period. For example, the first transmission period may be set to 1/60 second, and the second transmission period may be set to 1 second.

The manipulation unit 163 is an input means that allows the user to set the first and second transmission cycles with the support of the control unit 160.

The storage unit 165 is controlled by the control unit 160 and can be used to record recording target information, for example, weather information values currently decided to be transmitted, to compare changes in the future.

The communication unit 170 is controlled by the control unit 160 and processes the transmission target information to be transmitted to the PDC (Phasor Data Concentrator) 300 through the communication network 200, and the PDC 300 collects data from the monitoring server 400. It can be built to transmit information. Here, the PDCs 300 are constructed to transmit collected information to the monitoring server 400 through the communication network 200.

Therefore, the monitoring server 400 can be constructed to process the collected information by determining that if external sensing information is not received, it will remain the same as the previous value, and the monitoring server 400 can be configured to process the collected information with relatively little change over time. Data transmission efficiency, storage utilization efficiency for data storage, and processing efficiency for analysis can all be improved.

According to this synchronous phasor measurement device that supports external environmental information transmission, external sensing information as well as power sensing information including voltage and current phasor information can be provided as time synchronization data, and the transmission cycle of external sensing information can be longer than that of power sensing information. By applying it, it provides the advantage of improving data transmission efficiency and improving the utilization efficiency of storage resources.

Although embodiments according to the present invention have been described above, they are merely illustrative, and those skilled in the art will understand that various modifications and equivalent scope of embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the following claims.

110:GPS receiver 120:Phase-locked oscillator
130: sensor unit 140: noise filter
150: A/D converter 160: Control unit
170:Department of Communications

Claims (6)

A phase-locked oscillator that generates pulse signals in synchronization with the 1 pps (1 pulse per second) signal from the GPS receiver;
A sensor unit that measures voltage signals and current signals generated in the power system, environmental information around the measurement environment, and load power;
An A/D converter that converts the analog signal output from the sensor unit into a digital signal by using the pulse signal output from the phase-locked oscillator as an operation signal; and
Calculate a voltage phasor and a current phasor from the signal output from the A/D converter, transmit the power sensing information including the calculated voltage phasor and current phasor through a communication unit at a set first transmission cycle, and detect it in the sensor unit. A synchronous phasor measurement device comprising a control unit that transmits and processes environmental information and load power through the communication unit every second transmission cycle that is set to be longer than the first transmission cycle. According to paragraph 1,
The environmental information and load power transmitted every second transmission cycle are,
A synchronous phasor measurement device characterized in that it does not transmit if it is identical to the previous information. According to paragraph 2,
The environmental information above is,
A synchronous phasor measurement device comprising at least one of temperature, humidity, wind direction, wind speed, solar radiation, cloud cover, and fine dust amount. A data transmission method using the synchronous phasor measurement device of claim 1,
a) determining whether the first transmission period set by the control unit has reached;
b) When the first transmission cycle has arrived, transmitting power sensing information through the communication unit;
c) determining whether the second transmission period set by the control unit has reached;
d) When the second transmission cycle has arrived, determining whether the current environment information and load power information and the previous state environment information and load power information are the same; and
e) A data transmission method comprising transmitting the currently detected environmental information and load power information only when the determination result in step d) is not the same. According to paragraph 4,
A data transmission method, characterized in that the second transmission period is an integer multiple of the first transmission period. According to clause 5,
The second transmission cycle is a data transmission method characterized in that the user can change the cycle through the control panel.

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