# US 2019/0245337 A1 · Intelligent Electronic Device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0245337 A1 - Document ID: US20190245337A1 - Status: Published application - Kind: A1 - Application number: 16/320,212 - Filed: 2016-09-01 - Published: 2019-08-08 - Earliest claimed: 2016-09-01 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Shigetoo ODA - Web page: https://patentgrep.com/patent/US20190245337A1 ## CPC - H02H 1/0007: {concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445)} - G05B 15/02: electric - H02H 1/0092: {concerning the data processing means, e.g. expert systems, neural networks} - H02H 3/0935: {the timing being determined by numerical means} - H04B 3/46: Monitoring; Testing - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) - H04B: TRANSMISSION ## Abstract In an intelligent electronic device, a first receiving circuit receives first time-series data at a first sample rate representing the electrical quantity of an electric power system from a merging unit. An up converter converts the first time-series data into second time-series data having a second sample rate higher than the first sample rate by interpolating the first time-series data. A down converter converts the second time-series data into third time-series data having a third sample rate lower than the first sample rate by periodically extracting a data point at any changeable sample time from the second time-series data. A relay computer performs protective relay computation using third time-series data. ## Claims ### Claim 1 An intelligent electronic device comprising: a communication circuit to receive first time-series data at a first sample rate representing electrical quantity of an electric power system from a merging unit; an up converter to convert the first time-series data into second time-series data having a second sample rate higher than the first sample rate by interpolating the first time-series data; a down converter to convert the second time-series data into third time-series data having a third sample rate lower than the first sample rate by periodically extracting a data point at any changeable sample time from the second time-series data; and a relay computer to perform protective relay computation using the third time-series data. ### Claim 2 (depends on 1) The intelligent electronic device according to claim 1, wherein the down converter extracts partial data from the second time-series data every determined number of data points based on the first time-series data. ### Claim 3 (depends on 2) The intelligent electronic device according to claim 2, further comprising a frequency computer to calculate a system frequency at present of the electric power system, based on the first time-series data, wherein the determined number of data points is adjusted in accordance with the system frequency. ### Claim 4 (depends on 3) The intelligent electronic device according to claim 3, wherein the determined number of data points is smaller as the system frequency is greater than a rated frequency and is greater as the system frequency is smaller than the rated frequency. ### Claim 5 (depends on 1) The intelligent electronic device according to claim 1, further comprising a timing signal generator to generate a timing signal based on the first time-series data, wherein the down converter extracts partial data from the second time-series data at a timing in accordance with the timing signal. ### Claim 6 (depends on 5) The intelligent electronic device according to claim 5, further comprising a frequency computer to calculate a system frequency at present of the electric power system, based on the first time-series data, wherein the timing signal generator adjusts a period of the timing signal in accordance with the system frequency. ### Claim 7 (depends on 6) The intelligent electronic device according to claim 6, wherein the period of the timing signal is smaller as the system frequency is greater than a rated frequency and is greater as the system frequency is smaller than the rated frequency. ### Claim 8 (depends on 1) The intelligent electronic device according to claim 1, wherein the intelligent electronic device further comprises: a first data storage and a second data storage to store the second time-series data up to a predetermined time before present time while successively updating the second time-series data; and a counter, wherein when a failure is detected in the electric power system by the relay computer, the first data storage continues updating, the second data storage stops updating, and the counter starts counting, the down converter converts data stored in each of the first and second data storages into the third time-series data having the third sample rate, the intelligent electronic device further comprises a third data storage, and the third data storage stores the third time-series data and stores a value of the counter. ### Claim 9 (depends on 1) The intelligent electronic device according to claim 1, wherein the intelligent electronic device is disposed on a first end of a power transmission line, the intelligent electronic device further comprises: a transmitting circuit for transmitting a first synchronizing signal and the third time-series data to another intelligent electronic device disposed at a second end of the power transmission line through a digital transmission line, as a current signal on the first end; and a receiving circuit for receiving a current signal on the second end transmitted from the other intelligent electronic device through the digital transmission line and a second synchronizing signal, the receiving circuit further receives information of a first transmission/reception time difference from the other intelligent electronic device, the first transmission/reception time difference being a time difference from when the other intelligent electronic device transmits the second synchronizing signal to when the other intelligent electronic device receives the first synchronizing signal, the intelligent electronic device further comprises a synchronization processor, the synchronization processor further calculates a second transmission/reception time difference, the second transmission/reception time difference being a time difference from when the first synchronizing signal is transmitted to when the second synchronizing signal is received, and when generating the third time-series data, the down converter extracts a data point at a sample time that varies depending on a comparison result between the first and second transmission/reception time differences, from the second time-series data. ### Claim 10 (depends on 9) The intelligent electronic device according to claim 9, wherein when the first transmission/reception time difference is greater than the second transmission/reception time difference, the down converter extracts a data point at an earlier sample time from the second time-series data, in generating the third time-series data, and when the first transmission/reception time difference is smaller than the second transmission/reception time difference, the down converter extracts a data point at a later sample time from the second time-series data, in generating the third time-series data. ### Claim 11 (depends on 2) The intelligent electronic device according to claim 2, wherein the intelligent electronic device is disposed on a first end of a power transmission line, the intelligent electronic device further comprises a transmitting circuit and a receiving circuit for communicating with another intelligent electronic device disposed on a second end of the power transmission line, and the down converter changes a data point to be extracted from the second time-series data, based on information received from the other intelligent electronic device through the receiving circuit, together with information of the first time-series data. ### Claim 12 (depends on 5) The intelligent electronic device according to claim 5, wherein the intelligent electronic device is disposed on a first end of a power transmission line, the intelligent electronic device further comprises a transmitting circuit and a receiving circuit for communicating with another intelligent electronic device disposed on a second end of the power transmission line, and the timing signal generator generates the timing signal, based on information received from the other intelligent electronic device through the receiving circuit, together with information of the first time-series data. ### Claim 13 (depends on 1) The intelligent electronic device according to claim 1, wherein the second sample rate is equal to an integer multiple of least common multiple of the first sample rate and the third sample rate. ### Claim 14 (depends on 1) The intelligent electronic device according to claim 1, wherein the intelligent electronic device is applicable to both a first rated frequency and a second rated frequency different from each other as a rated frequency of the electric power system, the first sample rate is equal to a first integer multiple of the first rated frequency and equal to a second integer multiple of the second rated frequency, and the second sample rate is equal to an integer multiple of least common multiple of the first integer, the second integer, and the third sample rate.