Phasor measurement in a power system

Abstract

A phasor measurement device (PMD) may be provided. The PMD includes a clamp to clamp the PMD to a power line. An acquisition circuit may acquire a voltage signal and a current signal from the power line. An analog-to-digital converter is connected to the acquisition circuit. The analog-to-digital converter converts the voltage signal and the current signal to a first digital signal and a second digital signal respectively. A phasor microprocessor is connected to the analog-to-digital converter. The phasor microprocessor is configured to determine a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively. The phasor microprocessor is further configured to time stamp the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time.

Description

Attorney Docket No. 15720.1178WOU1PHASOR MEASUREMENT IN A POWER SYSTEMCross-Reference To Related Applications

[0001] This application claims the benefit of Indian Provisional Application No. 202411093702, filed November 29, 2024, titled “Phasor Measurement in a Power System,” the disclosure of which is hereby incorporated herein by reference in its entirety.Technical Field

[0002] The present disclosure relates generally to an electrical system and in particular to phasor measurements in the electrical power system.Background

[0003] The phasor measurements of voltages and currents from widely dispersed locations in an electrical power distribution and transmission network is used for monitoring, operation and control of the power system network. The phasor measurements are performed by Phasor Measurement Units (PMUs). PMUs are used for sending phasor data from different locations of the power systems. The phasor data include a magnitude and phase shift information of an instantaneous voltage and a current. The phasor data when relayed at a regular interval may help in improving the instantaneous structure of the voltage and current in the power system.

[0004] The cost of conventional PMUs is significantly high, and their size often makes them unsuitable for compact applications. Due to these limitations, utilities typically deploy PMUs at the substation level. However, as power grids rapidly evolve with increasing integration of renewable energy and advancements in power conservation and harvesting technologies at the customer and distribution level, the need for more localized monitoring solutions has grown.Summary

[0005] In accordance with some aspects of the present disclosure, a Phasor Measurement Device (PMD) comprises: a clamp configured to clamp the phasor measurement device to a power line; an acquisition circuit configured to acquire a voltage signal and a current signal from the power line; an analog-to-digital converter connected to the acquisition circuit, wherein the analog-to-digital converter converts the voltage signal and the current signal to a first digital signal and a second digital signal respectively; and a phasor microprocessorAttorney Docket No. 15720.1178WOU1 connected to the analog-to-digital converter, wherein the phasor microprocessor is configured to: determine a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively, and time stamp the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time.

[0006] In accordance with some other aspects of the present disclosure, a system for phasor measurement, comprises: a phasor measurement device clamped on a power line, the phasor measurement device comprising: an acquisition circuit configured to acquire a voltage signal and a current signal from the power line; an analog-to-digital converter connected to the acquisition circuit, wherein the analog-to-digital converter converts the voltage signal and the current signal to a first digital signal and a second digital signal respectively; and a phasor microprocessor connected to the analog-to-digital converter, wherein the phasor microprocessor is configured to: determine a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively, and time stamp the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time; and a phasor data concentrator configured to collect the phasor measurement from the phasor measurement device.

[0007] In accordance with some other aspects of the present disclosure, a method of determining a phasor measurement, comprises: acquiring, through an acquisition circuit of a phasor measurement device, a voltage signal and a current signal from a power line, wherein the phasor measurement device clamped on the power line; converting, by an analog-to- digital converter connected to the acquisition circuit, the voltage signal and the current signal to a first digital signal and a second digital signal respectively; determining, by a phasor microprocessor connected to the analog-to-digital converter, a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively; and time stamping the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time.Brief Description of the Drawings

[0008] Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, theAttorney Docket No. 15720.1178WOU1 dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0009] FIG. 1 illustrates an example power system.

[0010] FIG. 2 is a diagram illustrating components of a control system.

[0011] FIG. 3 is a diagram of a Phasor Measurement Device (PMD).

[0012] FIG. 4 is an example plot illustrating phases of a signal.

[0013] FIG. 5 is an example plot of a voltage signal with magnitude jumps.

[0014] FIG. 6 is a flow diagram of method of determining phasor measurements.

[0015] FIG. 7 is a diagram of a computing device.Detailed Description

[0016] In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as top, bottom, front, back, etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense.

[0017] FIG. 1 illustrates an example power system 100. As shown in FIG. 1, power system 100 includes a power generating plant 102, a transmission line 104, a substation 106, distribution lines 108, power consuming loads 110a, 110b, 110c. Power generating plant 102 generates power that is transferred to substations 106 through transmission line 104. Power from substation 106 is then distributed to power consuming loads 110a, 110b, 110c through distribution lines 108. Even though only certain system components (e.g., one power generating plant 102, one transmission line 104, one substation 106 etc.) are illustratedAttorney Docket No. 15720.1178WOU1 in FIG. 1, in other embodiments, power system 100 may include other system components in addition to or in lieu of those components shown in FIG. 1.

[0018] Power system 100 can also include a plurality of phasor measurement devices (PMDs) 120a, 120b, 120c, 120d, 120e, 120f (collectively “120). As described in a greater detail in the following sections of the disclosure, PMDs 120 can be configured to measure voltage, current voltage phase, current phase, and / or other types of phasor measurements in power system 100 based on a common time reference. Each PMDs 120 may include a clamp 122 and are clamped at different locations in power system 100. Each PMDs 120 are configured to acquire voltage and current phasor measurements at its location on power system 100. For example, and as shown in FIG. 1, a first PMD 110a is located at first power consuming load 110a, a second PMD 120b is located at a distribution line connecting first power consuming load 110, a third PMD 120 is located near third power consuming load 110c, a fourth PMD 120d is located on a distribution line connecting third power consuming loads 110c, a fifth PMD 120e is located in substation 106, and a sixth PMD 120f is located on transmission lines 104. The location of PMDs 120 may be determined by a grid operator and can dynamically be changed. For example, PMDs 120 may be provided at Point of Common Coupling (PCC), near larger power consuming loads (for example, first load 110a), Distributed Energy Resources (DERs), etc. Even though only six PMDs are shown in power system 100, a different number of PMDs may be used at different places in power system 100.

[0019] FIG. 2 illustrates a control system 150. Control system 150 may be used to view and manage operations of power system 100. Control system 150 includes a first network 155, a second network 160, a Phasor Data Concentrator (PDC) 170, and a control center 170. PMDs 120 may send the phasor measurements to PDC 170 via first network 155. In examples, first network 155 may be a power line communication network, an internet, an intranet, a wide area network, and / or other suitable types of networks. PDC 170 can be configured to receive the phasor measurements from PMDs 120 and process the received phasor measurements. In some examples, PDC 170 can be configured to receive and align the phasor measurements from PMDs 120 based on corresponding time stamps with reference to a a Global Navigation Satellite System (GNSS) or a Global Positioning System (GPS). In some examples, PDC 170 may sort, filter, average, and / or perform otherAttorney Docket No. 15720.1178WOU1 operations on the received phasor measurement data. PDC 170 may act as an edge device for running analytics responsible for situational awareness (control, analysis and monitoring).

[0020] PDC 170 may receive or fetch data from a predetermined number (for example, 12- 60) of PMDs 120. PDC 170 may include a memory to store the received phasor measurements and a processor to process the phasor measurements. PDC 170 may send the phasor measurements to control center 175 in batches. In some examples, PMDs 120 can directly send phasor measurements to control center 175 through a second network 160. In examples, second network 160 may be an internet, an intranet, a wide area network, and / or other suitable types of networks.

[0021] Control center 175 is configured to process the phasor measurement data received from PDC 170 or PMDs 120 may use the phasor measurement data for monitoring, operation, control and / or protection of the power system network. For example, control center 175 may determine any behavioral changes to supplied power. The behavioral changes may be due to: (a) insertion / removal of loads (for example, non-linear or linear loads); (b) insertion or removal of a renewable energy resources; (c) islanding or main griding; (d) power theft; (e) thermal loading; (f) harmonics or oscillations; (g) sag and swell; (h) climatic condition, etc. Control center 175 may further determine whether to send a command to appropriate power system devices or power system elements for protection functionality (e.g., shed generation, insert a system braking resistor or control a Static VAR Compensator). Control center 175 may include a Wide-Area Control Systems (WACS) controller, a Wide-Area protection system WAPS controller. In examples, control center 175 may be a Supervisory Control and Data Acquisition (SCAD A) system.

[0022] Control center 175 may identify an event based on the phasor measurements. Events may include a fault and a fault type (for example, line-to-ground fault, line-to-line faults, etc). In addition, control center 175 may identify the faulted power line. In some example, the events may include an over loading of power line or an unbalanced loading of a power line. Upon identification, control center 175 may reconfigure power system 100 to mitigate effect of the fault or the over loading.

[0023] FIG. 3 illustrates a block diagram of first PMD 120a. As shown in FIG. 3, first PMD 120a may include an acquisition circuit 202, an Analog-to-Digital (A / D) converter 204, a phasor microprocessor 206, a phase locked oscillator 208, a GPS receiver 210, and aAttorney Docket No. 15720.1178WOU1 communication module 212. Even though only certain system components (e.g., acquisition circuit 202, A / D converter 204, phasor microprocessor 206, phase locked oscillator 208, GPS receiver 210, and communication module 212) are illustrated in FIG. 3, in other embodiments, first PMD 120a may include other system components in addition to or in lieu of those components shown in FIG. 3.

[0024] Acquisition circuit 202 may acquire voltage and current values from the power line. For example, acquisition circuit 202 may include a current sensor and a voltage sensor for measuring the current and the voltage respectively. In some examples, the current sensor and the voltage sensor may be embedded in clamp 122 of PMDs 120. The measured current and voltage signals may be conditioned by a signal conditioner (not shown).Each measurement of a current and / or voltage is processed by either a common or separate respective signal conditioner, which may include an amplifier and an anti-aliasing filter, for example. The anti-aliasing filter (or a low pass filter) is used to filter out from the input waveform frequencies above the Nyquist rate.

[0025] The acquired voltage and current signals are then converted to digital data signals by A / D converter 204 where the digital data represents a magnitude of the input voltage and / or the input current at a sampling instant. A / D converter 204 may include a sampler or a sampling circuit that samples the voltage and current values at a sampling rate either determined by an administrator or as determined by the sampling signal that is referenced to a reference or sampling clock. The reference clock may be provided by phase-locked oscillator 208 and GPS receiver 210. The GPS-based clock provides an absolute time reference. The common synchronizing signal is available from the GPS-based clock to all PMDs 120. Phasor microprocessor 206 may synchronize its local clock based on the absolute time reference. In examples, the sample rate may be 7680 samples per second. In some other examples, the sample rate can be 15360 samples per second.

[0026] The digital data signals acquired at precise and pre-defined moments in time are then processed via phasor microprocessor 206. In one example, phasor microprocessor 206 may be an application-specific digital controller or a microprocessor to generate phasor measurements (also referred to as a synchrophasor). In one implementation, the phasor measurements are determined by phasor microprocessor 206 using a Discrete Fourier Transform (DFT). The phasor measurements are then combined into a data frame along with a time stamp and status information. Communication module 212 transmits the data frame toAttorney Docket No. 15720.1178WOU1PDC 170 via first network 155 and / or to control center 175 vis second network 160. In some examples, the data frame may be stored locally in a local memory at first PMD 120 and then be uploaded to PDC 170 or control center 175 in batches.

[0027] In examples, phasor microprocessor 206 as described above determines the phasor measurements as: x(t) = Xm Cos(ot + 0);X = (XmA / 2) Z0 where Xm is an amplitude, 0 is the phase shift at t=0, and o is an angular frequency of the phase voltage or phase current. In examples, each of PMDs 120 may deliver 10-30 phasor measurements per second. Each phasor measurement may be between 8-10 Bytes. Hence, transmission module 212 may be configured to determine an optimal network to send the phasor measurements through.

[0028] Phasor microprocessor 206 may further provide power outage indication and load information. For example, phasor microprocessor 206 may determine whether there is a power outage and provide an indication of the same. In addition, phasor microprocessor 206 may determine a load and a power factor on the power line. The load and the power factor may be determined based on the acquired voltage and current signals. Phasor microprocessor 206, thus, may also provide the load information of the power line. Phasor microprocessor 206 may provide a breaker ON / OFF status. In addition, phasor microprocessor 206 may geo tag or provide location information along with the phasor measurements and power outage indications. The location information may be obtained from GPS receiver 210.

[0029] In example implementations, each PMDs 120 may be a plug-and-play device that can be mounted directly on a power line. For example, each PMDs 120 may be clamped on a power line at any location on power system 100. A size of clamp 122 of PMDs 120 may be adjustable for different size conductors. Each PMDs 120 may also tap into the power line to power itself and its components (that is, acquisition circuit 202, A / D converter 204, phasor microprocessor 206, phase locked oscillator 208, GPS receiver 210, and communication module 212). For example, clamp 122 of PMDs 120 may include magnetic field sensors that may sense the magnetic field around the power line. In addition, each PMDs 120 may include a rechargeable battery to power components of PMDs 120 in case of loss of power on the power line. The rechargeable battery can be kept charged using the power drawn from the power line.Attorney Docket No. 15720.1178WOU1

[0030] PMDs 120 may provide Ipsec accuracy in the phasor measurement and may deliver 10-30 phasor measurements per second. In addition, PMDs 120 may send the phasor measurements as per Institute of Electrical and Electronic Engineers (IEEE) 37.118 standards. Thus, PMDs 120 may be deployed any power control systems without having a need for modification. In some examples, PMDs 120 may also be referred to as grid advisors. In some example implementations, PMDs 120 may also be referred to be microPhasor Measurement Units (pPMUs) as it is smaller in size compared to conventional PMUs. Because of the relatively smaller size, PMDs 120 can be easily clamped on a power line and deployed along distribution lines without requiring additional mounting support or infrastructure. In addition, PMDs 120 may be cheaper than the conventional PMUs.Therefore, multiple PMDs 120 can be deployed in power system 100.

[0031] FIG. 4 is an example plot 300 illustrating shifting phase angle for a voltage or a current signal 310. As shown in FIG 4, the phase angle for a current or a voltage signal may shift through time as represented as c[)o, 4>i, c[)2, c[)3, c[)4, etc. FIG 5 is another example plot 320 illustrating phase jumps in example voltage signals.

[0032] FIG. 6 is a flow diagram of a method 400 for determining phasor measurements. In examples, method 400 may be performed by PMDs 120. At stage 410 of method 400, phase current and / or voltage signals are acquired. As discussed above a current sensor and a voltage sensor of acquisition circuit 202 may acquire a phase current and phase voltage respectively. The phase current and the phase voltage may be associated with a power line on which PMDs 120 are clamped on.

[0033] At stage 420 of method 400, the acquired current and voltage signals are conditioned. For example, and as discussed above, an anti-aliasing filter (low pass filter) may be used to filter out from the input waveform frequencies above the Nyquist rate.

[0034] At stage 430 of method 400, the conditioned current and voltage signals are sampled. As discussed above, the conditioned current and voltage signals can be sampled at predetermined sampling rate, for example, 48-120 samples per second.

[0035] At stage 440 of method 400, the sampled current and voltage signals are converted into digital signals. For example, the current signal is converted into a first digital signal and the voltage signal is converted into a second digital signal. As discussed above, the sampled current and voltage signals are converted into digital signals by A / D converter 204.Attorney Docket No. 15720.1178WOU1

[0036] At stage 440 of method 400, phasor measurements are computed from the digital signals. For example, the phasor measurement is determined for each of the current signal and the voltage signal from the first digital signal and the second digital signal respectively. As discussed above, the phasor measurement is determined by phasor microprocessor 206. Phasor microprocessor 206 may also stamp the determined phasor measurement with a timestamp associated with a time of acquisition of the current signal and the voltage signal. In some examples, phasor microprocessor 206 may stamp the determined phasor measurement with a current time at phasor microprocessor 206. In some implementations, phasor microprocessor 206 may also geo tag the determined phasor measurement with location information of PMDs 120. The phasor measurements are then provided to PDC 170 and control center 175.

[0037] FIG. 7 shows computing device 500. As shown in FIG. 7, computing device 500 may include a processing unit 510 and a memory unit 515. Memory unit 515 may include a software module 520 and a database 525. While executing on processing unit 510, software module 520 may perform, for example, processes for determining phasor measurements as described above with respect to FIG. 5. Computing device 500, for example, may provide an operating environment for PMDs 120, PDC 170, and control center 175. PMDs 120, PDC 170, and control center 175 may operate in other environments and are not limited to computing device 500.

[0038] Computing device 500 may be implemented using a Wi-Fi access point, a tablet device, a mobile device, a smart phone, a personal computer, a network computer, a mainframe, a router, a switch, a server cluster, a network storage device, a network relay device, or other similar microcomputer-based device. Computing device 500 may comprise any computer operating environment, such as hand-held devices, multiprocessor systems, microprocessor-based or programmable sender electronic devices, minicomputers, mainframe computers, and the like. Computing device 500 may also be practiced in distributed computing environments where tasks are performed by remote processing devices. The aforementioned systems and devices are examples, and computing device 500 may comprise other systems or devices.

[0039] Implementations of the disclosure, for example, may be implemented as a computer process (method), a computing system, or as an article of manufacture, such as a computer program product or computer readable media. The computer program product may be aAttorney Docket No. 15720.1178WOU1 computer storage media readable by a computer system and encoding a computer program of instructions for executing a computer process. The computer program product may also be a propagated signal on a carrier readable by a computing system and encoding a computer program of instructions for executing a computer process. Accordingly, the present disclosure may be embodied in hardware and / or in software (including firmware, resident software, micro-code, etc.). In other words, implementations of the present disclosure may take the form of a computer program product on a computer-usable or computer-readable storage medium having computer-usable or computer-readable program code embodied in the medium for use by or in connection with an instruction execution system. A computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

[0040] The computer-usable or computer-readable medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium. More specific computer-readable medium examples (a non-exhaustive list), the computer-readable medium may include the following: an electrical connection having one or more wires, a portable computer diskette, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CD-ROM). Note that the computer-usable or computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via, for instance, optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory.

[0041] While certain implementations of the disclosure have been described, other implementations may exist. Furthermore, although implementations of the present disclosure have been described as being associated with data stored in memory and other storage mediums, data can also be stored on or read from other types of computer-readable media, such as secondary storage devices, like hard disks, floppy disks, or a CD-ROM, a carrier wave from the Internet, or other forms of RAM or ROM. Further, the disclosed methods’ stages may be modified in any manner, including by reordering stages and / or inserting or deleting stages, without departing from the disclosure.Attorney Docket No. 15720.1178WOU1

[0042] Furthermore, implementations of the disclosure may be practiced in an electrical circuit comprising discrete electronic elements, packaged or integrated electronic chips containing logic gates, a circuit utilizing a microprocessor, or on a single chip containing electronic elements or microprocessors. Implementations of the disclosure may also be practiced using other technologies capable of performing logical operations such as, for example, AND, OR, and NOT, including but not limited to, mechanical, optical, fluidic, and quantum technologies. In addition, implementations of the disclosure may be practiced within a general purpose computer or in any other circuits or systems.

[0043] Implementations of the disclosure may be practiced via a system-on-a-chip (SOC) where each or many of the element illustrated in FIG. 1 may be integrated onto a single integrated circuit. Such an SOC device may include one or more processing units, graphics units, communications units, system virtualization units and various application functionality all of which may be integrated (or “burned”) onto the chip substrate as a single integrated circuit. When operating via an SOC, the functionality described herein with respect to implementations of the disclosure, may be performed via application-specific logic integrated with other components of computing device 500 on the single integrated circuit (chip).

[0044] Implementations of the present disclosure, for example, are described above with reference to block diagrams and / or operational illustrations of methods, systems, and computer program products according to implementations of the disclosure. The functions / acts noted in the blocks may occur out of the order as shown in any flowchart. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality / acts involved.

[0045] While the specification includes examples, the disclosure’s scope is indicated by the following claims. Furthermore, while the specification has been described in language specific to structural features and / or methodological acts, the claims are not limited to the features or acts described above. Rather, the specific features and acts described above are disclosed as example for implementations of the disclosure.

Claims

Attorney Docket No. 15720.1178WOU1What is claimed is:

1. A phasor measurement device, comprising: a clamp configured to clamp the phasor measurement device to a power line; an acquisition circuit configured to acquire a voltage signal and a current signal from the power line; an analog-to-digital converter connected to the acquisition circuit, wherein the analog- to-digital converter converts the voltage signal and the current signal to a first digital signal and a second digital signal respectively; and a phasor microprocessor connected to the analog-to-digital converter, wherein the phasor microprocessor is configured to: determine a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively, and time stamp the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time.

2. The phasor measurement device of claim 1, further comprising: a communication module configured to transmit the phasor measurement to a phasor data concentrator over a first communication medium.

3. The phasor measurement device of claim 2, wherein the communication module is further configured to transmit the phasor measurement to a control center over a second communication medium.

4. The phasor measurement device of claim 1, further comprising: a sampler configured to sample the voltage signal and current signal at a predetermined sampling rate.

5. The phasor measurement device of claim 1, further comprising: a Global Positioning System (GPS) receiver configured to provide a GPS clock signal to the phasor microprocessor.

6. The phasor measurement device of claim 1, wherein the phasor microprocessor is further configured to:Attorney Docket No. 15720.1178WOU1 location tag the phasor measurement with location information of the phasor measurement device.

7. The phasor measurement device of claim 1, wherein the phasor microprocessor is further configured to: provide power outage indication; and provide load information.

8. A system for phasor measurement, the system comprising: a phasor measurement device clamped on a power line, the phasor measurement device comprising: an acquisition circuit configured to acquire a voltage signal and a current signal from the power line; an analog-to-digital converter connected to the acquisition circuit, wherein the analog-to-digital converter converts the voltage signal and the current signal to a first digital signal and a second digital signal respectively; and a phasor microprocessor connected to the analog-to-digital converter, wherein the phasor microprocessor is configured to: determine a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively, and time stamp the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time; and a phasor data concentrator configured to collect the phasor measurement from the phasor measurement device.

9. The system of claim 8, wherein the phasor data concentrator is further configured to align the phasor measurement from two phasor measurement devices based on corresponding time stamps with reference to a Global Positioning System (GPS).

10. The system of claim 8, wherein the phasor data concentrator is further configured to transmit the collected phasor measurement to a control center.Attorney Docket No. 15720.1178WOU111. The system of claim 8, wherein the phasor measurement device further comprises a communication module configured to transmit the phasor measurement to the phasor data concentrator over a first communication medium.

12. The system of claim 11, wherein the communication module is further configured to transmit the phasor measurement to a control center over a second communication medium.

13. The system of claim 8, wherein the phasor measurement device further comprises a sampler configured to sample the voltage signal and current signal at a predetermined sampling rate.

14. The system of claim 8, wherein the phasor measurement device further comprises a Global Positioning System (GPS) receiver configured to provide a GPS clock signal to the phasor microprocessor.

15. The system of claim 8, wherein the phasor microprocessor is further configured to: location tag the phasor measurement with location information of the phasor measurement device.

16. The system of claim 8, wherein the phasor microprocessor is further configured to: provide power outage indication; and provide load information.

17. The system of claim 8, further comprising a control center, wherein the phasor data collector is configured to transmit the phasor measurement to the control center.

18. A method of determining phasor measurements, the method comprising: acquiring, through an acquisition circuit of a phasor measurement device, a voltage signal and a current signal from a power line, wherein the phasor measurement device clamped on the power line;Attorney Docket No. 15720.1178WOU1 converting, by an analog-to-digital converter connected to the acquisition circuit, the voltage signal and the current signal to a first digital signal and a second digital signal respectively; determining, by a phasor microprocessor connected to the analog-to-digital converter, a phasor measurement for each of the current signal and the voltage signal from the first digital signal and a second digital signal respectively; and time stamping the phasor measurement each of the current signal and the voltage signal with a time stamp with a current time.

19. The method of claim 18, further comprising: transmitting, by a communication module connected to the phasor microprocessor, the phasor measurement to a phasor data concentrator over a first communication medium.

20. The method of claim 18, further comprising: altering loading on the power line based on the phasor measurement.

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