Claims:WE CLAIM
1. A device for protecting the wide area electrical power system networks comprising:
a Power Module (201);
a Redundant Power Module (202);
a Communication Module (203);
a Time Module (204);
a Main processing module (205);
wherein the power module (201) and redundant power module (202) supplies the voltage and driving current to the communication module (203), time module (204) and the Main processing module (205).
2. The device as claimed in claim 1, wherein the Main processing module (205) consists of multicore processor module (209), an FPGA module (208), a serial and Ethernet interface module (206), and a hard disk module (207).
3. The device as claimed in claim 1, wherein the multi core processor module (209) adopts an Intel multi core processor, FPGA module (208) consists of XILINX FPGA, hard disk module (207) consists of 512 GB of SATA SSD which can be expandable to 1 TB and serial interface module (206) adopts two ports for Serial 232/485 communication.
4. The device as claimed in claim 1, wherein the Ethernet interface module (206) consists of four independent 10/100/1000 LAN ports which can be configured independently for high speed communication.
5. The device as claimed in claim 1, wherein the communication module (204) consists of two Giga bit fiber optic SFP communication interfaces.
6. The device as claimed in claim 1, wherein the communication module (203) communicates with main processing module (205) through high speed PCIe interface
7. The device as claimed in claim 1, wherein the time module (204) adopts a fiber port and universal serial DB9 connectors for receiving time information through IRIG - B signal (306).
8. The device as claimed in claim 7, wherein the time module (204) also includes an output universal DB9 connector for sharing/synchronising the time information with other peer devices.
9. The device as claimed in claim 7, wherein the time module (204) adopts high speed PCIe bus (308) communication with main processing module
10. The device as claimed in claim 1 is capable to communicate with compatible intelligent electronic devices through optical/copper Ethernet network and compliant with IEC 61850-90-5 and IEEE C 37.118 protocol standards (304).
11. A method of protecting the wide area electrical power system networks comprising:
obtaining the time synchronised phasor information (currents /voltages) of the connected power system from various downstream devices;
time aligning the phasor information received from various downstream devices;
computing the system state and observability;
computing system's single machine equivalent (SME) phase;
issuing a control command to affect various power system relays if the SME phase deviates from any of the generation station node phase.
12. The method as claimed in claim 11, wherein the phasor information is exchanged between various modules through inter process communication
, Description:FIELD OF THE INVENTION:
[001] This invention relates generally to electrical power systems/grids and particularly to a device and a method for improving the power grid stability using synchronized phasor measurements and fast data processing in real time with multi core processors. More particularly the invention relates to a phasor data concentrator and a method of protection and visualization of power grid with fast communication.

BACKGROUND/PRIOR ART OF THE INVENTION:
[002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[003] Electrical power system networks are ever increasing in terms of power magnitude handled and vast geographical areas covered. Stable operation of these power networks is becoming increasingly complex. With the penetration of the renewables in to these systems the stable operation becomes even more complex and challenging. The modern day grid networks requires Wide Area Based Control and Protection systems for optimal, safe and secure operation. Wide Area Control and Protection systems (WACPS) consists of plurality of synchrophasor measurement transducers, synchrophasor/phasor data concentrators, high speed secured network connectivity and analysis software for control and protection of the current network. Synchrophasor measurement transduces or Phasor Measurement systems/units are basic building block for WACPS which are installed at major network node of the power network which computes voltage and current magnitude and phase angles with reference the GPS time. Phasor data concentrator is a smart/intelligent device which collates the phasor information of the network form the plurality of phasor measurement units through secured high speed network.
[004] The phasor information in digital form is transmitted between PMU and PDC’s through IEEE C 37.118 and IEC 61850-90-5 protocols for wide area measurement, control and protection applications. In general Wide Area Measurement, Control and Protection system are compliant to C.37.118 and IEC 61850-90-5 standards.

[005] In a prior art, CN109980635A, titled “Multi-branch combined computing phasor data concentrator implementation method” a method for computing virtual PMU and multi branch concentrator which is based on XML architecture. This work describes a method to obtain the grid adjustment capability of new solar/wind/pump storage power plant by the primary station by XML based multi-branch combined virtual PMU application.

[006] In another prior art, CN110601987A, titled “Data collection method for phasor data concentrator” describes an improved method of collecting phasor data obtain the state and preparing the common frame and send it to master station. Further this work also describes method for sync and out of sync phasor data collection from multiple PMU's simultaneously in real time.

[007] Another prior art, US 2004/0186670 A1 teaches a protection relay for distribution system which calculates KWH, KVAR etc. and secures the distribution system network with plurality of devices and phasor processor arrays for monitoring , control and protection.

[008] Another prior art, CN108650070A titled “System and method for communication of phasor measurement unit of information center network” describes a communication system of information center network phasor unit. This work describes the method for interest packet configuration between primary station and phasor data concentrator.

[009] Another prior art, US 20090088990 A1 titled “Synchronised Phasor Processor for a Power System” discloses a device and logic engine which performs calculations on the phasor data for operating other power system devices in the grid to achieve system stability.

[0010] Another prior art, CN109217963A, titled “Time alignment method for real-time phasor data of distribution network wide-area measurement system” discloses a time alignment method for real time phasor data processing by phasor acquisition unit. This work presents a method to avoid communication network delays and eliminates missing frame error.

[0011] Furthermore, CN206741693U, titled “Phasor data concentrator” discloses a phasor data concentrator with higher reliability and less interruption due to power disturbances and large storage capacity with in-built data exchange function

[0012] In view of the above, there is requirement to devise an apparatus which can address the aforesaid shortcoming(s). Hence, the present invention has been introduced.

[0013] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

OBJECTS OF THE INVENTION:
[0014] It is therefore the object of the present subject matter to overcome the aforementioned and other drawbacks in prior method/product/apparatus.

[0015] The present invention is based on the object of providing a Wide Area Control and Protection device for stability improvement of electrical power system to protect the connected power network from cascading trips by analysing the time synchronised phasor information of various electrical nodes over wide geographical area.

[0016] Said object is achieved according to the invention by the features of claim 1. Further, particularly advantageous embodiments of the invention are disclosed in the sub-claims.

[0017] Another object of the present invention is to provide a method for protecting the connected wide area power network from out of step synchronism.

[0018] Yet another objective of the present invention is to provide a device analyzes the connected wide area network phase angle stability and alerts the system operator about the connected network security and safety.

[0019] Yet another objective is to provide a system for depicting or visualising the network state from the received wide area phasor information and provides various trends and graphs for the system operator.

[0020] Yet another objective is to provide a device that analyzes the connected wide area network phase angle stability and alerts the system operator about the connected network security and safety.

[0021] Still another objective is to provide a device that estimates the state of the connected wide area network from data obtained from plurality of PMU's and PDC's.

[0022] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.
SUMMARY OF THE INVENTION:
[0023] One or more drawbacks of conventional systems and process are overcome, and additional advantages are provided through the apparatus/composition and a method as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be part of the claimed disclosure.

[0024] Accordingly, there is provided a device for wide area control and protection systems for electrical power grids. The device protects vast electrical power systems from catastrophic failures based on the data acquisition technology of phasor measurement unit and phasor data concentrator and monitors transmission system conditions over large areas to detect and counteract grid instabilities. Frequency, Voltage and Current measurements are taken by PMUs located at various electrical nodes in the power system. The synchronised phasor measurements of voltages of electrical nodes and currents through the transmission lines are measured with respect to common time reference like GPS by PMU's.

[0025] Consequently, these synchrophasors are processed by the wide area control and protection device. The logic engine of device time aligns the phasor data received from various PMU's and PDC's. The time aligned phasor data is presented to the operator as a snapshot to the network operator. The logic engine computes the network snapshots in real time providing the dynamic visibility to the grid operators.

[0026] The present invention further describes a wide area protection engine of the apparatus which continuously monitors the grid state by computing the state estimation, identifies the islanding situations and generates necessary control signals to the lower level devices like PMU's to operate various power system relays for the stability of the complete electrical network.
[0027] The present invention further describes a user interface for the network operator for easy viewing of the power system state and acts as early warning system for the grid operators. The apparatus is made compliant to the standard IEC 61850 with protocol conversion module of the communication module.

[0028] The present invention is achieved by the features of principal claim and subsequent claims.

[0029] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

[0030] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.

[0031] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
[0032] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:

[0033] Figure 1 shows the general system architecture of Wide Area Control and Protection.

[0034] Figure 2 shows various modules of Wide Area Control and Protection Device.

[0035] Figure 3 illustrates modular block diagram of Wide Area Control and Protection Device with inputs and outputs.

[0036] Figure 4 illustrates various processes of Wide Area Control and Protection Device.

[0037] Figure 5 illustrates the flow chart diagram for out of synchronism protection for the connected wide area network.

[0038] The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS:

[0039] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

[0040] The present invention makes a disclosure regarding a technology pertinent to improving the power grid stability using synchronized phasor measurements and fast data processing in real time with multi core processors.

[0041] The Present invention relates to the invention relates to the Wide Area Control and Protection device (107) which provides the snapshot of the connected power system to the operators and gives an early warning for slow developing instabilities in the network.

[0042] The Wide Area Control and Protection device (107) is a physical electronic device which provides the snapshot of the connected power system to the operators and gives an early warning for slow developing instabilities in the network. The device has communication capabilities for IEEE C 37.118 and IEC 61850-90-5 standards (304). The device receives network information from PMU's/PDC's viz. voltages of all connected nodes, currents through various branches, system frequency, rate of change of frequency, analog signals from various transducers, status information of various switches through digital signals, through IEEE C 37.118 (304) data frames. The device receives IRIG - B signals (306) for self-aligning its clock (401) to a standard GPS clock. The received wide area measurements are time synchronised by PMU's to the standard GPS clock and communicated to PDC's located at control centers as per C.37.118 standard protocol (304).

[0043] The device (107) checks for data errors, redundant/duplicity in the received network information and time aligns the phasor information received from various down level devices through C.37.118 (304) data frames. The received network information is analysed and presented to the network operators for easy understanding of the network status. The data received from lower level devices is stored for archival purposes in the dedicated data base servers. The device also communicates the received network data to higher level PDC's or super PDC's for analysis and further processing. The device (107) computes the connected network's single machine equivalent phase and alerts or isolates the predetermined nodes if this computed SME phase is deviating from the generation nodes phase angles by large margin thereby protecting the connected grid from out of synchronism and avoiding cascading tripping and blackouts. The Wide Area Control and Protection device (107) identifies the out of synchronism condition and sends a control command to the identified lower devices to effect various power system relays in order to safely operate the complete electrical network. The Wide area control and protection system can be installed at local level comprising of few intra-regional substations or at regional level receiving data from various substations in different regions, or at national level.

[0044] Now reference may be made to Figure-1 illustrating the general arrangement of Wide Area Control and Protection device in the electrical network. Time synchronised phasor information of the Network from various substations is directly communicated to central control centre (dispatch centre) using high speed dedicated optical fiber network. The Wide Area Control and Protection unit at central location receives this data for analysis and reporting to upper level devices and to data base servers for archiving. The received data is time aligned and presented to system operators for visualisation of current status of the power network. The control commands which are originated from the wide area control and protection device are communicated to lower level devices through the high speed network and these lower level devices intern operate the power system equipment to protect the grid.

[0045] Now referring to Figure-2 showing the modules within the present invented device. The power module (201) for the device, a second power module (202) for redundancy purposes, and these power modules energize the main processing module (205), Communication module (203) and time module (204). The main processing module (205) intern has a multicore processor (209), FPGA core (208), Hard disk (207) and serial and Ethernet interface (206).

[0046] Figure 3 illustrates the input/output channels for the present invention where main power module (201) and redundant power module (202) receives the auxiliary voltage (AC/DC) (301) from supply mains. This modules convert the input voltage to 24 V levels and supply into other modules/cards. Communication Module (203) receives the phasor information (304) from lower devices viz. PMU's /PDC's in the form of C.37.118 frames or IEC 61850-90-5 standards. Time module (204) receives the time information in electrical/optical form and can generate the synchronisation signals to synchronise the peer IED's. The time module (204) synchronises the internal clock (401) with the standard time reference. Multi core processor board (209) receives the phasor data from the communication module (305) through PCIe high speed bus (308) and through high speed direct interface. The hard disk module (207) is connected to the processor board through an internal bus communication.

[0047] Figure 4 explains the internal process of the present invention the time module (204) aligns the internal clock (401) to the external standard time reference. The communication module (403) receives the phasor data and communicates it to the data processing engine (404) the communication module (403) has a conversion engine for the IEC 61850 -90-5 protocol and presents it to the processing engine. Data processing engine (404 D) decodes the configuration frames and data frames and process the raw data extracted from these frames for data errors, duplicate data etc. The processed data is sent for storage and archival purposes to the available data base servers. Data processing engine also generates pictorial representation of the network status to the user through user interface (406). Network configuration and connected lower/upper level devices information is received from user interface (406). As per the device configuration and list of upper level devices common data/configuration frames are prepared and dispatched (407) to the connected devices. Wide Area Control and Protection engine (405) receives the phasor information from data processing engine and predefined limits from user interface for securely operating the network and generates necessary alarms and commands to user interface and lower level devices (403).

[0048] Synchrophasor devices have faster reporting rates when compared to traditional power system measurement devices. Due to higher reporting rate, real time dynamic conditions of power system can be assessed using the phasor information received by PDC. The time aligned phasor information can provide a bird’s eye view of power system at nodes from which the measurements were recorded. This perspective can be extended to nodes adjacent to the measurement nodes by computing their phasors using knowledge about the network topology together with time aligned phasor information. The computed phasors along with measured phasors would provide valuable insights about the real time conditions of the power system. These phasors can be used to build various applications which can assist the system operator in maintaining smooth operation of power system. Detection of loss of synchronization of generating nodes is one such application. In normal conditions all the generation nodes in a power system work in a synchronised manner and thereby maintaining the frequency close to the base frequency of the power system. Occurrence of large disturbances on power system may sometimes lead to loss of synchronisation as these disturbances lead to large excursions of the generator rotor angles. The loss of synchronism develops within seconds of occurrence of disturbance and will lead to the power network splitting into two or more islands. The occurrence of this condition can be identified by comparing the phase angles of generation nodes with respect to a common reference such as network’s single machine equivalent. Loss of synchronism can occur if phase difference of any generation node continuously increases with respect to common reference following the disturbance.

[0049] Figure 5 shows the flowchart of the real-time loss of synchronism detection process.

[0050] Step 501: Initializing the process to identify loss of synchronism in real time using phasor information.

[0051] Step502: Retrieving phasors information of various nodes which are time aligned by PDC.

[0052] Step 503: Using the phasor information and the network topology information, which is pre fed into the PDC, identify the nodes whose voltage phasor can be derived and declare them as observable and other nodes as unobservable.

[0053] Step 504: Identify if there are any changes to the observable nodes with respect to previously derived network observability.

[0054] Step 505: If change in network observability is found, compute network admittance matrix to reflect the changes in observable network.

[0055] Step 506: Using network admittance matrix and phasor information solve the network equations to derive the voltage magnitude and phase of observable matrix.

[0056] Step 507: Using the voltage phase values of nodes where net generation of active power is positive (generation nodes), compute network single machine equivalent model’s phase.

[0057] Step 508: Compute the phase difference between the generation nodes and network single machine model phase.

[0058] Step 509: Identify if phase difference of any generation node is greater than pre-defined limit. If yes go to step 510.

[0059] Step 510: issue a warning to operator regarding the loss of synchronization scenario.

[0060] The advantage of present Invention is that it alerts the system operator about the connected network security and safety.

[0061] The material above has been given as an example without restricting scope of the invention to the same. Thus, other materials readily apparent to a person skilled in the art are within scope of the invention.

[0062] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases, it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[0063] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

[0064] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particulars claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogues to “at least one of A, B and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B”.

[0065] The above description does not provide specific details of manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.

[0066] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.

[0067] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.

[0068] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.