1. Field of the Invention
The invention relates to power distribution systems and, more particularly, to such systems for communicating with, monitoring and/or controlling network protectors and/or associated equipment, such as sensors and/or devices.
2. Background Information
Low-voltage secondary power distribution networks consist of interlaced loops or grids supplied by two or more sources of power, in order that the loss of any one source will not result in an interruption of power. Such networks provide the highest possible level of reliability with conventional power distribution and are, normally, used to supply high-density load areas, such as a section of a city, a large building or an industrial site.
Each source supplying the network is typically a medium voltage feeder system including a switch, a voltage reducing transformer and a network protector. As is well-known, a network protector is an apparatus used to control the flow of electrical power to a distribution network. The network protector includes a circuit breaker and a control relay which opens the circuit to the transformer upon detection of abnormal current flow. Specifically, the control relay typically senses the network voltages, the line currents and the phasing voltage, and executes algorithms to initiate circuit breaker tripping or re-closing actions. Trip determination is based on detecting reverse power flow, that is, power flow from the network to the primary feeder. Examples of network protector relays are disclosed in U.S. Pat. Nos. 3,947,728; 5,822,165; 5,844,781; and 6,504,693, which are incorporated by reference herein.
Voltage is safely supplied to the network through the transformers, which have their secondary or low-voltage windings connected to the network through the circuit breaker of the corresponding network protector. The transformers and network protectors are often located in vaults, which are frequently underground.
As is also known, control relays typically include a microcontroller-based circuit which monitors the network phase-to-neutral voltages, the phasing voltages and the feeder currents. Traditionally, if a problem with a transformer and/or network protector arose, a worker would need to manually inspect the installation to investigate the problem by physically entering the vault which houses the transformer and/or network protector. This presents serious safety concerns for workers, as the environment inside the vaults is dangerous due to, among other things, the toxic environment and/or the relatively high voltages, currents and temperatures involved.
In order to alleviate this safety concern, the control relays in some systems include a communication module for wired communication with a remote station over a communication network to allow remote access to protector measurement data of interest for both diagnostic and control purposes. In such systems, the control relays perform circuit breaker trip and re-close functions, and the connection to the communication network enables remote tripping, or more specifically, “remote open and block open” control. This allows users, such as electric utility maintenance personnel, to remotely open, and under certain conditions, close the circuit breaker of a network protector, as described in detail in, for example, U.S. Pat. Nos. 5,936,817 and 6,504,693, which are incorporated by reference herein.
The remote station 25 receives network protector measurement data of interest from and sends circuit breaker open and/or close commands to one or more of the network protectors 10 over the communication cable 15. Such a system is, however, typically relatively expensive to implement, as large amounts of cable must be run over long distances.
U.S. Pat. No. 6,628,496 describes a protection system for an electricity network that includes a box containing a processor that causes circuit breakers to open in the event of faults being sensed by current and/or voltage sensors on the lines of the network connected to the circuit breakers. The system also includes a short range radio data transmission link between the box and a remote appliance, such as a mobile telephone, PDA or laptop. As a result, the remote appliance is able to receive data from and send commands to the box wirelessly. This system, however, is a point-to-point system, meaning that a communication channel must be established individually with each such box in order to collect data therefrom or to provide commands thereto. In order to do so, the remote appliance must be brought within the RF transmission range of each such box, which, in most cases, will require a worker to travel over significant distances. As a result, performing diagnostic and control functions with such a protection system is inefficient and time consuming. In addition, such a system requires each box to have its own wireless communication device, which adds to the cost of the system overall.
There is, thus, a need to provide connectivity between network protectors and personnel responsible for network protector up-time, maintenance and operation thereof. Such network protectors are located in widely scattered underground vaults and have the important goal of providing reliable electrical power distribution and protection to critical infrastructure (e.g., large buildings; factories; electrical utilities).
There is room for improvement in communication systems that address local and remote control and monitoring of network protectors, sensors and/or devices.
This need and others are met by embodiments of the invention, which provide flexible connectivity through the integration of a set of wireless network technologies. For example, a wireless network architecture comprises wireless personal, local and wide area network technologies integrated through a gateway. The gateway includes, for example, wireless personal, local and wide area communication network interfaces that provide pervasive and flexible control and monitoring of geographically scattered network protectors, sensors and/or devices by personnel located at a remote location (e.g., from a control/monitoring and dispatch center) and/or a local location (e.g., in the vicinity of a network protector, sensor and/or device; at street level).
In accordance with one aspect of the invention, a power distribution communication system comprises: a number of network protectors; a number of sensors or devices; a number of wirelessly communicating user interfaces; and a gateway comprising: a wired communication network interface structured to communicate with at least one of the network protectors, the sensors or the devices, a first wireless communication network interface structured to wirelessly communicate with at least another one of the network protectors, the sensors or the devices, a number of second wireless communication network interfaces structured to wirelessly communicate with the wirelessly communicating user interfaces, and a processor operatively associated with the wired communication network interface, the first wireless communication network interface and the number of second wireless communication network interfaces.
The number of second wireless communication network interfaces may include at least one of a wireless local area communication network interface and a wireless wide area communication network interface.
The number of second wireless communication network interfaces may include a wireless local area communication network interface and a wireless wide area communication network interface.
As another aspect of the invention, a power distribution communication system comprises: a number of network protectors; a number of sensors or devices; a number of wirelessly communicating user interfaces; a wired communication network; a gateway comprising: a wired communication network interface structured to communicate with a first group of some of the network protectors, the sensors or the devices over the wired communication network, a number of first wireless communication network interfaces structured to wirelessly communicate with the wirelessly communicating user interfaces, and a processor operatively associated with the wired communication network interface and the number of first wireless communication network interfaces; and a number of second communication network interfaces structured to provide communications between: (a) the wired communication network interface through the wired communication network, and (b) a second group of some of the network protectors, the sensors or the devices through wireless communications, the second group being different than the first group.
The number of first wireless communication network interfaces may be one first wireless communication network interface.
The one first wireless communication network interface may be a Wi-Fi Hot Spot interface.
The number of first wireless communication network interfaces may be a first wireless communication network interface and a second wireless communication network interface.
The first wireless communication network interface may be a Wi-Fi Hot Spot interface and the second wireless communication network interface may be one of an Ethernet cellular modem, an Ethernet radio modem and a fiber optic modem.
A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:
As employed herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).
As employed herein, the term “wireless” shall expressly include, but not be limited by, radio frequency (RF), light, visible light, infrared, ultrasound, wireless area networks, such as, but not limited to, IEEE 802.11 and all its variants (e.g., without limitation, 802.11a; 802.11b; 802.11g), IEEE 802.15 and all its variants (e.g., without limitation, 802.15.1; 802.15.3, 802.15.4), IEEE 802.16 and all its variants, other wireless communication standards (e.g., without limitation, ZigBee™ Alliance standard), HyperLan, DECT, PWT, pager, PCS, Wi-Fi, Bluetooth™, and cellular.
As employed herein, the term “communication network” shall expressly include, but not be limited by, any local area network (LAN), wide area network (WAN), intranet, extranet, global communication network, the Internet, wired communication network and/or wireless communication network.
As employed herein, the term “wireless communication network” means a communication network employing wireless communications.
As employed herein, the term “wired communication network” means a communication network employing non-wireless, wired communications.
As employed herein, the term “sensor” means an apparatus structured to input data or information and to output related data or information to a wireless communication network or a wired communication network. A sensor may optionally include or be operatively associated with zero or a number of devices. Non-limiting examples of sensors include sensors structured to sense temperature, voltage, current, voltage (stray) (e.g., from an energized, conducting surface that might be harmful or lethal to a service person or other person), gas (dissolved), gas (atmospheric), humidity, liquid level, pressure, sudden pressure (e.g., of a transformer compartment which sudden pressure might precede a catastrophic failure) and/or video information.
As employed herein, the term “device” means an apparatus structured to input data, information or a control command from a wireless communication network or a wired communication network and to output corresponding data, corresponding information or a corresponding control action. A device may optionally include or be operatively associated with zero or a number of sensors. Non-limiting examples of devices include fans, actuators, trip units, annunciators, and indicators.
As employed herein, the term “wireless communicating user interface” shall expressly include, but not be limited by, any communicating device having a user input and/or output interface and a wireless communication port (e.g., without limitation, a wireless communicating device; a personal computer (PC); a data phone; a remote control, dispatch or monitoring center; a portable wireless communicating device).
As employed herein, the term “portable wireless communicating device” shall expressly include, but not be limited by, any portable communicating device having a wireless communication port (e.g., without limitation, a portable wireless device; a portable personal computer (PC); a Personal Digital Assistant (PDA); a portable data phone).
As employed herein, the term “gateway” shall expressly include, but not be limited by, any node on any communication network that serves as an entrance and/or exit to and/or from one or more other communication networks that use different operational protocols.
As employed herein, the term “gateway/controller” shall expressly include, but not be limited by, a gateway that is structured to monitor a number of discrete inputs and/or to autonomously react to the discrete inputs and control some number of discrete outputs.
Referring to
One of the wirelessly communicating user interfaces 122 is operatively associated with a remote system 136, which is above ground. The example nodes 102,104,106,108 communicate with the gateway 124, and, in this example, are located below ground. The second wireless communication network interface 132 is a wireless wide area communication network (WAN) interface structured to communicate with the remote system 136 through a global communication network, such as the example Internet 138, which may employ wired, wireless and/or fiber optic communication. The remote system 136 is structured to monitor a number of the nodes 102,104,106,108 (e.g., network protectors and/or sensors), control a number of the nodes (e.g., network protectors and/or devices), or accumulate data from a plurality of the nodes (e.g., network protectors and/or sensors) over a geographical region formed by a number of underground vaults, such as 140,142. Although two example vaults are shown, one, three or any suitable number of vaults may be employed.
The gateway 124 is located in the underground vault 140 and a plurality of the nodes, such as 106,108 (e.g., network protectors, sensors and/or devices) are located in the other underground vault 142, which, in this example, is adjacent the first underground vault 140. The wired communication network interface 126 is structured to communicate with a wired/wireless data collector 144 including a wired communication network interface 146 communicating with a number of nodes (e.g., network protectors, sensors and/or devices), such as 108, located in the second underground vault 142 and a wireless communication network interface 148 wirelessly communicating with a number of nodes (e.g., network protectors, sensors and/or devices), such as 106, also located in the second underground vault 142.
The example INCOM wired communication network interface 178 is structured to communicate with a first group of some of the network protectors 152,154, the sensors 156,158 or the devices 160,162 over the INCOM serial sub-network 172. In this example, the INCOM serial sub-network 172 communicates with the example serial collectors 174,175 and the network protectors 152,154. The example serial collectors 174,175 are structured to provide communications between: (1) the wired communication network interface 178 through the INCOM serial sub-network 172, and (2) a second group of some of the network protectors 152,154, the sensors 156,158 or the devices 160,162 through wireless communications. In this example, the serial collector 174 in one underground vault 186 employs wireless communications (e.g., without limitation, ZigBee™ Alliance standard) to communicate with the sensor 156 and the device 160, while the other serial collector 175 in another underground vault 188 employs wireless communications (e.g., without limitation, ZigBee™ Alliance standard) to communicate with the sensor 158 and the device 162.
The system 200 of
The system 202 of
The system 220 of
The system 222 of
The system 224 of
The system 250 of
The system 250 includes the INCOM serial sub-network 172 and a wireless Zigbee sub-network, through the wireless low rate-personal area network interface 252, that typically, although not necessarily, are located underground, such as under street 254. The network protectors, such as 152, typically include at least a circuit breaker (not shown) and a control relay (not shown), each one operatively coupled to a transformer (not shown) and an associated electrical network (not shown).
The example gateway/controllers 176,176A,176B are electronic devices that include among other components: (1) the processor 182, such as, without limitation, a microprocessor, such as a microcontroller, that is programmed for performing the various operations and functions described herein; (2) a number of wireless communication interfaces capable of wirelessly transmitting and receiving data using any of one or more known wireless protocols, including, without limitation, short-range RF protocols such as Bluetooth or Zigbee; (3) a wired communication interface capable of transmitting and receiving data using any suitable wired protocol, including, without limitation, INCOM; and (4) a memory (not shown) for storing data and routines executable by the processor 182.
The example gateway/controllers 176,176A,176B provide an In-vault Communication Service (ICS) that directly gathers critical information from the various network protectors, sensors and/or devices located, for example, in a single vault or in plural adjacent underground vaults, and from the environment surrounding the network protectors (e.g., the vaults; the area immediately above the vaults). The ICS provides, for example: (1) the initial data collection from local electronic devices, sensors and/or network protectors; and (2) final delivery of a number of control commands to the network protectors and/or to a number of devices (e.g., fans; actuators) that are part of the network and that are located in the vaults.
The ICS is provided, for example, through a suitable wireless communication network (e.g., without limitation, Zigbee; Low-Rate Personal Area Network (LR-PAN)), such as through the wireless low rate-personal area network interface 252 (
Non-limiting examples of physical variables that are monitored by the ICS include: temperature, voltage, current, voltage (stray) (e.g., that could energize a sidewalk grating or any unexpected contact surface within the vault), gas (dissolved), gas (atmospheric), humidity, liquid level, pressure, sudden pressure (e.g., of a transformer oil housing), ionizing radiation and/or video information.
The various network protectors, sensors and/or devices may be provided within a vault underground. Typically, to provide adequate protection, such vaults are made of concrete and are rather thick (e.g., about 2 to 3 inches or more) and, as a result, wireless signals may not be able to penetrate the concrete. Fortunately, such vaults are also provided with a grating 256 (
In this example, the system 250 is a master/slave system. Specifically, gateway/controller 176B is both the INCOM master and the Zigbee master. The network protectors 152,153,154 and the serial collector 175 are INCOM slaves, and the sensor 156, device 160 and network protector 161 are Zigbee slaves, such that data communication is initiated by the gateway/controller 176B either on its own, as described below, or upon receipt of a request from a client system, such as for example and without limitation, a portable wireless communicating device, such as PDA 170, or a remote station (not shown) through remote long range communication through the example above-ground cellular infrastructure 208. Also, the serial collector 175 is a Zigbee master and the sensor 158, device 162 and network protector 163, in this example, are Zigbee slaves.
For example, in one particular embodiment, the gateway/controller 176B may be programmed to automatically and continuously, periodically or upon the occurrence of an event, such as a circuit breaker trip, collect data from one or more of, and preferably all of, the various network protectors, sensors and devices. Once collected, the gateway/controller 176B will then store (log) the data, preferably in a non-volatile manner, for subsequent transmission to the portable wireless communicating device 170 or a remote station (not shown), as described below.
The gateway/controller 176B is able to communicate with each of the various network protectors, sensors and/or devices. In particular, the gateway/controller 176B is structured to selectively request and receive data from and provide control commands to each of the various network protectors and devices. As such, the gateway/controller 176B is able to collect data, such as, without limitation, the network phase-to-neutral voltages, the transformer phase-to-neutral voltages, the feeder currents, the circuit breaker status (open or closed), and a stored log or buffer of recent breaker events, that is collected by the microcontroller-based control relay of each network protector, and is able to selectively provide breaker trip and re-close commands to each network protector. For this purpose, each of the various network protectors, sensors and devices is provided with a unique address to enable the gateway/controller 176B to identify it and distinguish it from the other network protectors, sensors and devices.
The example gateway/controllers 176,176A,176B provide a Local Access Service (LAS) that employs a suitable Wireless Local Area Network (WLAN) (e.g., without limitation, an IEEE 802.11-based network) to provide communication capabilities for a field operator to control and/or monitor the various network protectors, sensors and/or devices located within vaults that are scattered in a relatively small geographical region (e.g., a city block).
The LAS provides: (1) field operator monitoring of a number of network protectors and their environment; (2) field operator control of a number of network protectors and/or a number of networked devices; and (3) data aggregation of in-vault data tailored for field operation in a relatively small geographical region (e.g., a city block).
The example portable wireless communicating device, which may be, for example and without limitation, a portable personal computer, the PDA 170 or a cell phone, is provided with wireless communication functionality that is compatible with the WLAN LAS employed by the gateway/controller 176B to enable the portable wireless communicating device and the gateway/controller 176B to communicate with one another. As a result, the portable wireless communicating device 170 is able to wirelessly request and receive from the gateway/controller 176B the data that has been collected from each of the various network protectors, sensors and/or devices. In addition, the portable wireless communicating device 170 is able to wirelessly transmit control commands for one or more of the various network protectors and/or devices to the gateway/controller 176B, which then relays them to the appropriate network protectors and/or devices over the corresponding wireless communication network through the wireless low rate-personal area network interface 252 or over the INCOM wired communication network 172 through the INCOM interface 178.
As will be appreciated, the gateway/controller 176B is provided with appropriate hardware and software to enable the data to be converted from the format in which it is received over the example INCOM wired communication network 172 or the example Zigbee wireless low rate-personal area network to the internal format (e.g., without limitation, comma separated value (CSV) files; XML formats; any suitable representation of data in any organized manner) that is employed for processing by wireless gateway/controller 176B and to the format that is employed to transmit it wirelessly to the portable wireless communicating device 170 (e.g., Bluetooth, Wi-Fi, or any other suitable wireless local area network technology) and vice versa.
The example gateway/controllers 176A,176B provide a Remote Access Service (RAS) that employs a suitable Wireless Wide Area Network (WWAN) to provide communication capabilities for a remote or mobile operator to control and/or monitor a number of the various network protectors, sensors and/or devices located within vaults that are scattered in a relatively large geographical region (e.g., a city).
Examples of WWANs include, for example, cellular radio networks (e.g., GPRS; IS-95; CDMA2000, 1xEV-DO; GSM) or future IEEE 802.16-based networks.
The RAS provides: (1) mobile or remote operator monitoring of electrical parameters and surrounding network protector environment; (2) mobile or remote operator control of a number of network protectors and/or a number of networked devices; and (3) data aggregation of in-vault and local data tailored to remote and mobile operation in a relatively large geographical region (e.g., a city). The RAS includes services that the Internet can provide and, in particular, those services that can be provided through the client-server paradigm to access remote information via web servers (e.g., as part of the gateway/controllers 176A,176B) and web browsers.
The RAS may include, for example, some of the services of the LAS of Example 16. Therefore, it is possible for a mobile or remote operator to access a network protector, sensor or device through the RAS even if the user is within the LAS range. This can be beneficial, for instance, in case the LAS is temporarily unavailable.
Referring again to
Ideally, a user is interested in secure access to corresponding network protectors, sensors and devices. Therefore, access to/from the Internet 138 is preferably done through a firewall (not shown) and a web server (not shown) connected to an internal network (e.g., a company intranet) (not shown) at the remote system 136. For example, in such an installation, e-mail and/or paging alerts are possible from the information gathered by the gateway 124.
The example gateway 124 (
In addition, the example gateway 124 (
The system 270 of
The system 280 of
The gateway/controller 292 of
The gateway/controller 302 of
The gateway/controller 312 of
The various configuration links 356,358,360,362 display screens (not shown) that permit the user to configure the corresponding network protector, phase current sensor, network protector vault temperature sensor, and vault water sensor, respectively.
The various view trend links 364,366,368,370 display screens (not shown) that trend the corresponding network protector status, phase current status, vault temperature, and water in vault status, respectively, versus time.
The various download links 372,374,376,378 download the trend information and time values for the corresponding network protector status, phase current status, vault temperature, and water in vault status, respectively.
The Resolve All Events link 380 disarms all the alarms. For example, some automatic or manual actions have been taken beforehand by the crew personnel to resolve the issues in the network protector. The gateway/controller unit, in turn, stops sending alarm signals to the remote control dispatch and monitoring center. The Event History link 382 displays a pop-up display 384 of events needing attention and corresponding dates and times.
By selecting one of the links 332,334,336,338 of
In addition to the periodic and automatic update of the values/status for the sensors and the network protectors, the user may request values/status on demand. When the user clicks on one of the links 332,334,336,338 of
The sensors and network protectors transmit their values/status periodically with a period of about 20 seconds to the main application in the web server 264 of the gateway 124, which refreshes the corresponding web page and stores the last values from the sensors and the network protectors. The main application responds to on demand queries by sending the last values and status of the particular queried node and the web server 264 updates the web page.
In order to improve bandwidth usage, the main application in the web server 264 may send all of the last values and status from all sensors and network protectors, even though the user is interested in one or more particular values.
As seen in
Physical access to the network protector vault, such as 140 or 142, takes a relatively long time in view of the safety procedures to be followed by the utility crew. The disclosed system 100 allows personnel to quickly assess whether the vault needs to be accessed or not. The system 100 also enables the incorporation of control and monitoring systems (not shown) that can be used for diagnostics and prognostics.
For example, inspection of real-time parametric data, logged data since a previous visit, and video information (if available), can all lead to a relatively quick assessment of network protector health. Should any of this data indicate a potential anomaly, then an in-depth manual inspection can follow. With remote control, the network protectors can be exercised while under close supervision of the data collection portion of the system 100. Some network protectors even include internal diagnostic functionality that further enhances any routine physical operation of the network protector.
Currently, electric utilities rely on physical inspection of the vaults. The disclosed system 100 provides communication to and from the vault from and to the outside world, thereby saving a large number of man-hours. This provides the flexibility to have in-vault, local and remote access to a number of network protectors, a number of devices and/or a number of sensors. Furthermore, in addition to monitoring and/or control applications, the gateway 124 may provide the level of functionality tailored to the particular applications (e.g., a user may be interested only in remote access, only in local access, or only in in-vault communications with a selected number of sensors).
While for clarity of disclosure two sub-network interfaces 126,128 are shown being connected to one gateway 124, it will be appreciated that three or more sub-network interfaces, each including a number of sensors, devices and/or network protectors, may be connected to the single gateway 124, and that a number of gateways, each being connected to a plurality of sub-networks, may be included in a system within the scope of the invention.
As shown in
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.
This invention was made with Government support under DOE Cooperative Agreement No. DE-FC26-04NT42071 awarded by DOE. The Government has certain rights in this invention.