Patent Application
20130064178
Not Applicable.
Not Applicable.
Not Applicable.
The disclosure relates to a system for monitoring an electrical power distribution system using a wireless sensor network.
Electrical power distribution systems often include overhead electrical power distribution lines mounted upon poles by a wide variety of mounting structure. Other distribution systems include underground distribution lines in which protected cables run under the ground surface. High voltage phasing meters are designed for use as safety tools by maintenance line workers to verify the status voltage and phase of the grid lines, phase angle between the lines and also phase sequencing. Even though feeder circuits in utility lines are intended to be well balanced in the initial deployment, one of the phases may turn out to be more heavily loaded than others. This leads to load imbalances.
Known high voltage phasing meters comprise high resistance reference and meter probes connected in series with a calibrated panel meter to read the voltage across the phase-to-phase or phase-to-ground terminals. They are designed for use as safety tools by high voltage line maintenance workers to verify the status of the line or equipment as nominal, induced or de-energized. Known devices for providing such measurements include contact type and non-contact type. With contact type a reference probe or transmitter and a meter probe or receiver are connected in series with a cable as the loop is closed with load terminals. With the non-contact type each probe has a meter and the probes close the circuit through wireless means.
The smart grid is a modern electric power grid infrastructure for improved efficiency, reliability and safety. The smart grid utilizes smooth integration of renewable and alternative energy sources through automated control and modern communication technologies. In the smart grid, reliable and on-line information becomes an important factor for reliable delivery of power from the generation units to the end users. The impact of equipment failures, capacity of limitations, and natural accidents and catastrophes, which cause power disturbances and outages, can be largely avoided by on-line power system condition monitoring, diagnostics and protection. There is a need for continuous, uninterrupted, real time monitoring of grid parameters as part of a smart grid system.
Presently, smart meter reading solutions are available to monitor home meters, end user facilities and the like with respect to energy consumption. Monitoring of load conditions and grid performance is available at a substation level. Otherwise, there are various high voltage phasing meters and the like, as mentioned above, used for mainly diagnosing the distribution and utility grids. These are designed for use of safety tools to verify the status voltage and phase of the grid lines, phase angle between the lines and hence phase sequencing. A variety of phasing meters are used in a manual mode for diagnosis. However, none of these options provide continuous monitoring and intercommunication.
A sensor network diagnoses and monitors electrical power distribution lines in a power grid.
There is disclosed herein a system for monitoring electrical power distribution lines comprising a plurality of mesh networks. Each mesh network monitors electrical power distribution lines at a select location of the power grid. Each mesh network comprises a plurality of wireless sensors adapted for wireless communications therebetween. Each wireless sensor measures attributes of line voltage for an associated electrical power distribution line at the select location. A master sensor collects data from the other sensors in the mesh network and determines voltage and phase attribute data of the electrical power distribution lines at the select location. The master sensor comprises a gateway device for communication outside of the mesh network. A monitor device for communication with master sensors receives voltage and phase attribute data from the master sensors for monitoring operation of the electrical power distribution line power grid.
It is a feature that the monitor device comprises a handheld device.
It is another feature that the monitor device comprises a personal computer.
It is another feature that the master sensor synchronizes timing of the wireless sensors in each mesh network. The master sensor may synchronize timing responsive to receiving GPS data.
It is still another feature that the wireless sensors in each mesh network communicate with each other using Wi-Fi communications.
It is a further feature that the wireless sensors in each mesh network communicate with each other using Zigbee communications.
It is yet another feature that each wireless sensor is affixed to the associated electrical power distribution line.
It is still another feature that each master sensor determines phase angle measurement and phase sequencing for the master sensor's associated mesh network.
It is yet another feature that the gateway device is adapted to communicate with the monitor device using internet protocol.
There is further disclosed a sensor network for diagnosing and monitoring electrical power distribution lines in a power grid comprising a plurality of mesh networks each for monitoring electrical power distribution lines at a select location of the power grid. Each mesh network comprises a plurality of wireless sensors adapted for wireless communications therebetween. Each wireless sensor measures attributes of line voltage for an associated electrical power distribution line at the select location. One of the wireless sensors comprises a master sensor. The master sensor is adapted to collect line voltage data from the other sensors in a mesh network and environmental data at the select location that is adapted to determine voltage and phase attributes and prepare sample data of electrical power distribution lines at the select location. The master sensor comprises a gateway communication device for transmitting the samples of data outside of the mesh network. A monitor device in communication with master sensors receives sample data from the master sensors for diagnosing and monitoring operation of the electrical power distribution line power grid.
Other features and advantages will be apparent from a review of the entire specification, including the appended claims and drawings.
Described herein is a system for monitoring electrical power distribution lines uses sensor networking with phase ID meters permanently affixed to the distribution and utility grids and equipment. Referring initially to
A wireless mesh network 20 is provided in association with power grid 10 for monitoring electrical power distribution lines 13-18 at the location of the tower 12. The mesh network 20 comprises a plurality of wireless sensors 21, 22, 23, 24, and 26, also referred to herein as probes or wireless probes. Each probe 21-26 is affixed to and measures attributes of line voltage for an associated electrical power distribution line 13-18, respectively. For example, the first probe 21 measures attributes of power on the first line 13. The probes 21-26 are adapted for wireless communications therebetween. As described more particularly below, the first probe 21 comprises a master probe for collecting data from the other probes 22-26 in the mesh network 20 and determines voltage and phase attribute data of the electrical power distribution lines at the select location. The phase attribute data may include phase of the grid lines, phase angle between the lines, phase sequencing, and the like. As is apparent, any of the probes 21-26 could function as the master probe.
Each probe 21-26 comprises a phase ID meter and supports sensing for monitoring voltage, fault current, phasing attributes and physical parameters of the grid, such as temperature, humidity and ambient pressure and frequency of the high voltage signal. How the sensing is performed does not form part of the invention and thus is not discussed in detail herein. Each probe 21-26 could obtain power from its associated high voltage line 13-18, respectively. For measurement purposes, the probes 21-26 must synchronize their clocks. The master probe 21 may act as a master clock and provide synchronized time to the other probes 22-26. Also, the synchronized time could be provided from GPS time. The time synchronization among the probes 21-26 is used for phase attribute measurements as described below. Each probe 21-26 is configured with Wi-Fi or Zigbee communication to communicate therebetween in the mesh network 20. External long haul communication is performed using systems such as GSM/GPRS, etc.
As shown in
Referring to
Referring to
The algorithms of the router 50 and the gateway 52 can be included in the first probe 21 to render it a master probe
Referring to
As described, the system 40 provides 8 solution for monitoring the overall health of the power grid 10 using individual mesh networks 20. This grid level monitoring facilitates speedy and efficient troubleshooting by maintenance workers who have access to details of every grid between utility distribution points. The use of GPS also enables a prior survey for location of probes and thus localizes points of fault and assists in troubleshooting. This system 40 facilitates knowing the grid status at the substation and at other remote locations of interest and provides real time alerts to improve efficiency and quality of grid maintenance.
The wireless sensor networks provide a feasible and cost effective sensing and communication solution for remote system monitoring and diagnosis. The efficient monitoring system constructed of large scale deployment of smart sensor nodes can provide complete information on system components, including generation units, transformers, transmission lines, motors, etc. in a remote and online manner. With the online system monitoring and system level coordinating controls and protections, a single system contingency in the power grid or facility could be detected and isolated before it causes cascading effects and results in more catastrophic system breakdowns.
The gateway node device 52 may be provided with storage capability for storing the sample data for the particular mesh network 20. All of the parameters measured by the probes 21-26 in the mesh network 20 are continuously monitored by built-in control logic in the gateway 52. In case any parmeter heing monitored exceeds an operational limit, an alert message can be generated by the gateway 52 and transmitted to the server 48 or the like for decision making. The decision could prompt an operational crew to speed up maintenance activity while ahead of any possible failure or power outage or hazard. Historical data stored in the gateway 52 could be used for trend analysis, estimation of power losses or outages and pre-scheduling maintenance activities and component replacements. Alternatively, all computations and decision making could happen in the gateway and the critical information could be transmitted to the sub-station or server to reduce load and cost on the long haul network.
It will be appreciated by those skilled in the art that there are many possible modifications to be made to the specific forms of the features and components of the disclosed embodiments while keeping within the spirit of the concepts disclosed herein. Accordingly, no limitations to the specific forms of the embodiments disclosed herein should be read into the claims unless expressly recited in the claims. Although a few embodiments have been described in detail above, other modifications are possible. For example, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. Other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Other embodiments may be within the scope of the following claims.
The present invention has been described with respect to block diagrams. It will be understood that each block of the block diagrams can be implemented by computer program instructions. These program instructions may be provided to a processor to produce a machine, such that the instructions which execute on the processor create means for implementing the functions specified in the blocks. The computer program instructions may be executed by a processor to cause a series of operational steps to be performed by the processor to produce a computer implemented process such that the instructions which execute on the processor provide steps for implementing the functions specified in the blocks. Accordingly, the illustrations support combinations of means for performing a specified function and combinations of steps for performing the specified functions. It will also be understood that each block and combination of blocks can be implemented by special purpose hardware-based systems which perform the specified functions or steps, or combinations of special purpose hardware and computer instructions.
