GB2475565A

GB2475565A - Identifying an appliance by data on the earth pin of its plug

Info

Publication number: GB2475565A
Application number: GB0920577A
Authority: GB
Inventors: Chi Biu Wong; Philip Moore
Original assignee: De Montfort University
Current assignee: De Montfort University
Priority date: 2009-11-24
Filing date: 2009-11-24
Publication date: 2011-05-25
Also published as: WO2011064535A2; GB0920577D0; WO2011064535A3

Abstract

An energy management system comprises a central processing unit for monitoring and controlling an electrical power supply, and one or more electrical devices capable of being plugged into electrical power sockets of that power supply using electrical plugs which are square 3-pin plugs of the kind used in the United Kingdom. Each plug carries along the top edge 5 of its earth pin 4 encoded data for identifying the associated electrical device, and each socket includes a reader (7, Fig 3) positioned to read the encoded data when the plug is inserted into the socket, and means for communicating the encoded data to the central processing unit. The reader therefore communicates to the central processing unit in real time the identity of each electrical device connected to the power supply, which permits active control of the power supply. The data may be a bar code and may be printed directly onto the pin or onto a strip of paper, foil or film adhered to the pin. Alternatively, it may be a series of indentations or protrusions on a plastic or foil strip (6, Fig 2).

Description

TITLE

Energy Management System.

DESCRIPTION

Field of the Invention.

The invention relates to an energy management system for monitoring energy consumption, providing an indication of the health of an electrical appliance or device plugged into an electrical power supply, and optimizing the use of energy through active control of the use of each such appliance or device.

BACKGROUND

Proposals exist for energy management systems which monitor and even control the supply of electrical power through a power supply network in a domestic or industrial environment such as a home or factory. It is essential for the optimal use of such a system that the central processing unit (CPU) of the management system should be capable of identifying the electrical appliances or devices plugged into the system and drawing power. Typically a CPU would have an associated keyboard, so that a user could input to the CPU an identification of the device or devices connected to the supply network, optionally together with an identification of the power outlet socket from which each is drawing power. The CPU could then monitor the power consumption of each device, and either log that power consumption for a report to be printed out at a later date or actively control the power supply to that device. For example, if the CPU were able to identify that a device were drawing electrical power in a manner incompatible with the normal functioning of the device, and if it were also told which power outlet socket the device was plugged into, then it could intervene and cut off the power to that device while maintaining the power supply to all other devices connected to the supply network.

It will be appreciated that it is desirable for the identification of each device and the electrical power outlet socket from which it is drawing power to be done automatically and in real time, so that no keyboard input (which is time-consuming and liable to operator error) is needed before the CPU can monitor the power consumption and control the power supply to each individual device. That until now has been an evasive desideratum, because it would be too expensive to install in each device a transmitter for transmitting to the CPU a device identification and an indication of the location of that device, enabling the CPU to keep a log of which devices are drawing power from which electrical outlet power supply sockets. Even if each device were provided with a RFID transponder and each socket were provided with a transceiver for scanning for RFID transponders in the vicinity, the system could not be set up with sufficient accuracy to identify which device was connected to each individual socket. The best that could be achieved would be to identify that a particular device was in the proximity of a particular socket or group of sockets.

The invention provides a solution to the above problem.

THE INVENTJON

The invention provides an energy management system according to claim 1. The invention is based on the observation that the top edge of the earth pin of a square 3-pin plug is the only edge which does not fulfil any other function in any currently commercially available plug/socket combination. The side edges of the earth pin are used to make contact with the earth terminal of the socket in use. The bottom edge, being the edge nearest the live and neutral pins, may be used to contact a lever or cam inside the socket, to cause a cover or shroud over the live and neutral terminals to be moved aside as the plug is inserted into the socket. The top edge has no common function. According to the invention it is that top edge which carries encoded data for identifying the associated electrical device. That encoded data may printed onto the earth pin top edge directly or on an adhesive strip secured to the top edge of the earth pin. In normal use of the device, whenever its associated plug is inserted into a power outlet socket, the earth pin is pushed into the corresponding earth aperture in the socket and can be directly accessed by the reader in the socket. That reader can be an optical reader for reading an identification code such as a bar code, which has the advantage that there needs be no physical contact with the identification code as the plug is inserted into the socket. The plug can therefore be inserted into and removed from the socket for any number of times without experiencing any physical abrasion of the identification code along that top edge.

As an alternative, the encoded data may be an array of protrusions or indentations formed along or in the top edge of the earth pin of the plug, and the reader may be a probe or an array of probes for sensing the pattern of the protrusions or indentations.

Such protrusions or indentations may be formed directly on or in the top edge of the earth pin, or may themselves be protrusions or indentations formed on or in a surface of an adhesive strip adhered to the top edge of the earth pin. It is necessary only that such an adhesive strip should have the strength to maintain the coded data in readable form to withstand multiple insertions of the plug into different power outlet sockets.

The electrical power socket may be a fixed wall power socket or a socket of a power adaptor or extension cable. If, for example, the power socket is one of the sockets of a 1 -to-2 or I -tho-3 power adaptor which itself plugs into a fixed wall power socket to present two or three socket connections for other electrical devices, then the adaptor is preferably provided with encoded data along the top edge of its earth pin identifying it as an adaptor, and a reader together with means for communicating the read encoded data to the processing unit.

The processing unit may be a central processing unit (CPU) receiving data from a number of electrical devices simultaneously and which controls the electrical power supply accordingly, or it may be an individual processing unit associated with the particular individual power socket, for example as a piece of firmware embedded into that socket. Such embedded firmware can if desired be upgraded throughout its lifetime via a built-in radio communications link or via other mechanisms such as a built-in communications port such as a RS232 or USB port.

A particular advantage of the energy management system of the invention is that the processing unit is made aware of which electrical device is plugged into which power outlet socket in real time, without the need for any keyboard entry. Of course, that information is only as reliable as the reliability of the encoded data correctly identifying the device to which the electrical plug corresponds. However sealed electrical plugs are becoming quite widely used, and it follows therefore that once a plug is coded to identify the device to which it is connected, that coding will be an accurate identification of the electrical device for the lifetime of the device. If an electrical plug is used which can be opened up for rewiring, to permit the plug to be changed, then the use of an adhesive strip as described above for carrying the encoded data to identify the electrical device is a most useful opinion.

The system of the invention requires a reader in each socket. Each reader must be able to transmit the encoded data from the plug to the processing unit. If that processing unit is a piece of firmware embedded in the socket itself, then that may be a hard-wired communications link. If the processing unit is a remote CPU, then technology exists for that transmission of data to be down the wire conveying the power supply to the socket, but it will usually be preferred for the transmission of data to be a low power radio frequency communication, communicating the data identifying both the device plugged into any socket and the socket itself directly to the CPU. A ZigBee TM or ZWave TM communication device is suitable. Each power socket would need to be provided with such a device, but that is an acceptable level of expense as compared with the cost of having an embedded ID chip and RFID at each electrical device and at each socket.

The automatic real-time identification of what electrical device is plugged into which socket enabled a range of advanced functions to be realized in terms of power consumption active control and monitoring. To take but a few examples, if an expected power consumption of an electrical device is recorded in the processing unit or CPU, then when the system senses that such a device has been plugged into an electric power supply network, the system can monitor the power consumption of the device and can either warn the user in a printed data report or through other alert mechanisms such as text messaging if the device is showing an abnormal power consumption pattern, or can disconnect that particular socket from the system, thereby preventing further use of a device with a fault condition. If the device is a charger for a mobile phone, then the processing unit or CPU can be loaded with information concerning the optimum charge time, and the power supply automatically terminated when that charge time has been attained. If the device is a television set with a standby facility, then unnecessary power consumption can be reduced if the processing unit or CPU causes the power supply to be terminated when the standby power consumption level has been detected for more than a predetermined time duration. All of this is possible in an otherwise conventional system of energy consumption monitoring and control simply because the system according to the invention has the ability to monitor in real time the range of electrical devices plugged into the power supply network, and the power sockets into which the different identifiable devices are individually plugged.

DRAWINGS

Figure 1 is a perspective view of a square 3-pin power plug.

Figure 2 is a perspective view of an adhesive strip with a row of indentations providing encoded data to identify the electrical device attached to the plug.

Figure 3 is a schematic diagram illustrating the inter-relationship between the plug of Figure 1, the associated electrical device and a power outlet socket in a system according to the invention.

Referring first to Figure 1, there is shown an electrical plug of the conventional UK square 3-pin' shape and design. It has a neutral pin 2, a live pin 3 and an earth pin 4.

The earth pin 4 has a top edge shown marked 5, being the edge remote from the neutral and live pins 2 and 3. It is that top edge 5 which carries encoded data relating to the electrical device to which the plug 1 is attached though its power cable.

The encoded data may be any suitable printed data such as a bar code printed directly onto the top edge of the earth pin 4 or onto a strip of adhesive paper or foil or film adhered to the edge 5. The edge 5 fulfils no other purpose in an electrical plug. It is the sides of the earth pin which conventionally contact the earth contactors of the socket, and it is the bottom face which contacts a cam or lever in the socket to move to one side a shroud or shield which protects the line and neutral terminals in the socket. The encoded data should be capable of identifying the device to which the plug is connected sufficiently for the energy management system to make predictions as to its expected normal pattern of power consumption in normal use, and is read by a reader (not shown in Figure 1) as will be explained later.

As an alternative to having the encoded data printed on the edge 5 or on an adhesive strip applied to the edge 5, it may be incorporated into a series of indentations or protrusions in or on the surface of an adhesive strip such as the strip 6 shown in Figure 2. Figure 2 shows, by way of illustration, a strip 6 of adhesive plastic or foil which is perforated with a row of punched holes. The adhesive strip 6 is adhered to the top edge 5 of the plug 1 as shown in Figure 1, exactly as described above with reference to a strip of printed paper or foil. The pattern in the spacing of the holes is such as to identify the device to which the plug I is connected. The plug 1 with a strip 6 attached to the top edge of the earth pin is used not with an optical reader but with a reader which comprises a series of proximity sensors or probes which identify the pattern and thus the device with which the plug is connected.

Figure 3 gives an overview of the entire energy management system of the invention.

The plug I of Figure 1 can be plugged into any of a series of electrical outlet sockets in a domestic or commercial situation. Figure 3 shows the socket choice as being either of two sockets in a twin socket installation. Each socket has an associated reader 7 which may be an optical reader for reading the data encoded in a printed identification code along the top edge 5 of the earth pin 4 of the plug 1, or a series of probes or proximity sensors for reading the data encoded in the protrusions or recesses discussed above in relation to Figure 2. The data read by either of the readers 7 is then transmitted via a link 8 to a CPU 9. The link 8 may be a short range radio link such as a ZigBee TM or ZWave TM link, but is sufficient to ensure that the CPU can recognize what devices are plugged into the individual socket outlets of the twin socket installation of Figure 3. Either the CPU can either simply display or print out data concerning the usage of electricity at the sockets or it can control the electrical power. The energy management system is greatly facilitated by the ability of the system to recognize, in real time, the individual electrical devices 11 as they are plugged into the different sockets in the electrical distribution network.

Claims

CLAIMS1. An energy management system comprising: a central processing unit for monitoring and controlling an electrical power supply, and one or more electrical devices capable of being plugged into electrical power sockets of that power supply; wherein the or each electrical device capable of being plugged into an associated electrical power socket has an electrical plug fitted thereto for providing that connection, being a square 3-pin plug of the kind used in the United Kingdom, characterized in that each plug carries along the top edge of its earth pin, being the edge remote from the live and neutral pins, encoded data for identifying the associated electrical device, and each socket includes a reader positioned to read the encoded data when the plug is inserted into the socket, and means for communicating the encoded data to the central processing unit.
2. An energy management system according to claim 1, wherein the encoded data comprises optically recognizable data and the reader is an optical reader.
3. An energy management system according to claim 2, wherein the encoded data is printed on an adhesive slip secured to the top edge of the earth pin.
4. An energy management system according to claim 2, wherein the encoded data is printed directly onto the top edge of the earth pin.
5. An energy management system according to any preceding claim, wherein the encoded data is a bar code.
6. An energy management system according to claim 1, wherein the encoded data comprises an array of protrusions or indentations formed along or in the top edge of the earth pin, and the reader is a probe or proximity sensor or an array of probes or proximity sensors for sensing the pattern of the protrusions or indentations.