WO2008107214A1

WO2008107214A1 - An apparatus and method for controlling electrical power usage

Info

Publication number: WO2008107214A1
Application number: PCT/EP2008/050392
Authority: WO
Inventors: Luigi Pichetti; Marco Secchi; Antonio Secomandi; Alessandro Donatelli
Original assignee: International Business Machines Corporation; Compagnie Ibm France
Priority date: 2007-03-06
Filing date: 2008-01-15
Publication date: 2008-09-12
Also published as: JP2010520736A; KR20100003285A

Abstract

A solution forcontrolling and managing the usage of domestic electrical power in order to avoid undesired interruption of the service. According to a preferred embodiment of the present invention, a removable device is proposed which can be interposed between any appliance and the meter to prevent and manage power break down in a home electrical system. The device interacts with a server which monitors and controls the total electrical power usage of the system; the server authorisesnew requests of power consumption by any of the appliances only if such requests can be satisfied without exceeding a predetermined maximum allowed load of the system.

Description

An apparatus and method for controlling electrical power usage

Field of the invention

The present invention relates to the information technology field. More specifically, the invention relates to electrical power metering systems.

Background Art

The problem of controlling and managing the usage of domestic electrical power in order to avoid undesired interruption of the service is a well known and long felt problem. Modern integrated electrical systems provide some protections and some mechanisms which try to prevent and manage these accidents.

For example co-pending application EP 06127206.8 filed on 27 December 2006 discloses a method and system for an integrated system which prevents and/or manages excessive power loads with an interaction between the appliances or the electricity points within the house and the electric meter.

The above described method and system, however requires some form of "intelligence" in the wiring system and it is conditioned by the level of such "intelligence". This is not a big issue when the electrical power system is designed with this object in mind and all the components are integrated and properly communicate with each other. On the other hand, when similar protection and controlling system are to be applied to an existing system, things might be a little more difficult. For this reason a more flexible system which allows to adapt an existing electrical power usage metering system would be highly desirable.

It is an object of the present invention to overcome the above described drawbacks of the prior art.

Summary of the Invention

According to the present invention we provide an apparatus for controlling power usage adapted to be connected to an electrical power network system, the system including a server element monitoring the power usage of the system, the apparatus including: first electrical connecting means to connect at least one electrical power consuming element to the apparatus; second electrical connecting means to connect the apparatus to the electrical power network system; means for detecting a start command for the at least one electrical power consuming element, when the at least one electrical power consuming element is connected to the apparatus; means for determining the required amount of electricity power, necessary for the at least one electrical power consuming element; means for transmitting to the server a request for the required amount of electrical power; means for receiving a response from the server; switching means, responsive to an authorisation received by the server, to connect the at least one electrical power consuming element to the power network system.

Reference to the drawings The invention itself, as well as further features and the advantages thereof, will be best understood with reference to the following detailed description, given purely by way of a non-restrictive indication, to be read in conjunction with the accompanying drawings, in which:

Figure 1 is a schematic block diagram of a data processing system in which the solution according to an embodiment of the invention is applicable;

Figure 2 (2a and 2b) illustrates an exemplary application of the solution according to an embodiment of the invention;

Figure 3 shows the possible interaction between server and clients according to a preferred embodiment of the invention; and

Figure 4 is a diagram describing the flow of activities relating to an implementation of the solution according to an embodiment of the invention.

Detailed Description

With reference in particular to Figure 1, a distributed data processing system 100 is illustrated. The system 100 has a client/server architecture, wherein server 105 manages a plurality of clients 110. Multiple clients 110 are connected to server 105 (for example, clients 110 can be coupled to household or electronics appliances, e.g. washing machine, DVD recorders, computers) . For this purpose, the server 105 and the clients 110 communicate through a network which allows to communicate the intention to turn on the appliance/switch associated to a given client; typically, the network 115 is implemented by means of a medium which is able to carry electronic control signals, for example by means of conveyed waves, which is a common method to propagate low voltage control signals over regular electrical wires (e.g. 220/110 volts and 50/60 hertz) . This allows each client 110 to access the server 105, even remotely. Besides conveyed waves over electrical wires, alternative ways can be used for exchanging control signals between server and clients, e.g. any radio frequency signals, suitable for home-ranges (i.e. WiFi) or Bluetooth signals.

Particularly, the server 105 consists of a computer being formed by several units that are connected in parallel to a system bus 120. In detail, one or more microprocessors (//P) 125 control operation of the server 105; a RAM 130 is directly used as a working memory by the microprocessors 125, and a ROM

135 stores basic code for a bootstrap of the server 105.

Several peripheral units are clustered around a local bus 140

(by means of respective interfaces) . Particularly, a mass memory consists of one or more hard-disks 145. Moreover, the server 105 includes input units 160 (for example, a keyboard), and output units 165 (for example, a monitor) . An adapter 170 is used to connect the server 105 to the network 115. A bridge unit 175 interfaces the system bus 120 with the local bus 140. Each microprocessor 125 and the bridge unit 175 can operate as master agents requesting an access to the system bus 120 for transmitting information. An arbiter 180 manages the granting of the access with mutual exclusion to the system bus 120.

According to a preferred embodiment of the present invention, clients 110 are removable devices which can be interposed between the power network and the corresponding appliances without any modifications needed to the wiring system or to the appliance itself.

With reference to Fig 2a a preferred embodiment of the present invention is shown. According to this embodiment, client 110 is a removable device which can be interposed between an electrical device (e.g. a house appliance) and the server 105 (not shown in this Figure) e.g. as female/male plug adaptor. For the rest of the present description we will refer to the server 105 as "power enabler device" (PED) while we will refer to client 110 as "Power request broker Devices"

(POD) . Optional control 201 can be used to set and adjust the value of expected power load which will be required by the corresponding device once it has been connected. This value will be communicated to the PED in order to get consensus to the new requested power load. Manual adjustment it's the most simple way of setting the POD, but more advance method and system could be implemented instead, as better explained later.

Fig 2b shows a schematic diagram of the main components of POD. Modules 203 and 205 are needed to communicate with server 105 over network 115. CW sender 203 sends <ID> and/or <needed load> CW signal to PED. CW receiver 205 awaits the response by PED 105. Conveyed Waves seems to be the best solution for transmitting information between POD and PED; they can transmit low-voltage control signals over power lines, however alternative transmission solutions might be implemented as discussed. Module 207 causes the circuit to close and provides the requested power to the associated device, once consensus by the PED has been obtained. In this described embodiment a relais module is used, but those skilled in the art will easily understand that other equivalent solutions could be used instead. A sensor 209 is needed to detect that a new power load is being requested and triggers the transmission of the request to the PED. Optionally sensor 209 can be more sophisticated and automate handshaking renewal, to handle situations where permanent-connected appliances gets turned on, or where appliances with varying power consumption levels are to be managed. Such sensor can detect that the appliance is being powered on, i.e. a significant power variation is demanded from the appliance, in addition to the stand-by current. The measurement can be obtained, for example with a current meter which is able to report the dynamic resistance variation. More complex embodiment are possible for the POD which could be provided with additional modules, e.g. an internal memory to keep track of previous requests or for storing useful information on the associated appliance consumption needs. A more advanced embodiment of the POD could implement an introspection feature which is able to inspect the associated appliance in order to detect its factory load characteristics. This would avoid the manual initial setup.

Another possible implementation is to embed the POD directly into the appliance. Many modern electrical appliances include electronic control logic (dishwashers, washing machines, microwave ovens, all electronic appliances, etc) , and hence can be easily extended to host such additional POD logic. Being POD embedded in the appliance, greater interaction among POD and appliance can be implemented. For instance, it is not only possible to introspect factory parameters about standard power needs (e.g. static info like peak needs) but to introspect current appliance settings (e.g. amount of heat / cold needed) and to estimate the more accurate electrical power needs, according to such current settings. In this way, when POD sends a power-on request to the PED, it can be much more precise about the real appliance power needs. An additional possible feature is the ability to detect varying power needs, for appliances which have a time-varying load demand. In this case POD can exchange control signals with PED, not only for power on requests, but in general, for all the significant status variation needs. For example, during a 2 hours cycle of a typical washing machine, there are repeated activities which require a modest power load (300-500 watts during washing or wringing time), in addition to a couple to time-delimited activities which however requires intensive power load (1-1.3 kWatts, for water heating, but just 5 to 10 minutes) . Being embedded POD able to interact with both appliance internal state, and with PED for consensus, it can act as a real-time broker and make more frequent, power-accurate requests to the PED, and figure out if the appliance can switch among its consumption status, or if it has to wait for a consensus.

If the POD is able to introspect (e.g. with the power request detection sensor) the appliance status, it is possible to automate interaction with PED, without specific human intervention. So, not only the user can interact through the appliance interface directly, without the need to interact with switches of the electrical home system, but it is also covered the scenario where "time" or "events" (through a timer/scheduler or a thermostat) are automatically orchestrating appliances. For instance at a given time, in an unattended house, a thermostat tries to trigger the air conditioning on, because a time/temperature threshold is reached, but at the same time a dishwasher was operating; also in this unattended scenarios, PODs and PED will prevent unattended overload situations, load activation may be denied or deferred, and messages logged. Also, being PODs able to optionally introspect or even interact with appliance load characteristics and its power settings, POD can send more accurate power load demand requests, when interacting with PED. This can be beneficial both in term or maximizing usage of total available load among house appliances, and in term of time-orchestration of time-varying loads for dynamic appliances .

With reference to Fig 3, PODs 110 are connectable to one or more appliances 301 on one side and to the PED through the electrical wires on the other side. PED 105 is normally connected to the meter/switch 303 and to one or more PODs 110. In a state of the art home electrical system PED 105 provides a functionality which can range from a mere alerting service to a proper control and management of the electricity consumption within the house. PED could be located anywhere between the main meter/switch, normally provided by the electrical distribution company, and the household appliances or, more in general, the electrical devices to be managed. Its preferred location is however inside the apartment itself, near the remainder of the main internal switches (normally used to section the electrical network between e.g. 10 and 16 A loads) . The meter/switch 303 can be either a legacy electro-mechanical model or an electronic one.

In any case, according to a preferred embodiment of the present invention, the role of the PED is to give consensus, whenever a new appliance is being turned on.

As described in co-pending patent application EP

06127206.8, there are many different scenarios with corresponding different ways of working of the PED, depending on the amount of logic that we can assume to be inside the different PODs of the house (it is not necessary that all PODs have the same level of logic)

EMBODIMENT ONE

According to a preferred embodiment of the present invention, each POD is not only able to send an ID signal to the PED, but is also able to receive a consensus signal, over the wire. Once such consensus signal is received (e.g. a CW signal) , it will then activate the power to the associated appliance, acting in a "relais" mode as described with reference to Fig 2b above. The advantage of this solution, is that no direct wiring is needed from PED to PODs, as consensus signals are routed through junctions to the proper switch (e.g. "<switchIDXack>" or "<switchIDXnoack>") . Also, in this case all junction wires to PODs are always powered (as in today's layouts) and it's the switch that, working in relais-mode, powers the appliance when consensus is got from PED. PODs really act as real power switches with the difference that power-on happens only if they receive consensus from the PED.

EMBODIMENT TWO

According to a more simple embodiment, the only information a POD is able to transmit over the wire is a unique signal ID (e.g. unique deviation out of a base CW frequency, or a unique resistance) each time the corresponding appliance or device is switched on (for either turning on lights or enabling an appliance) .

PED receives signal IDs from POD, and have a static table where, for each ID, it lists the associated known load. PED is normally connected to a power meter, so it's instantly aware of the current total load in use, it's able to forecast if, giving power to the wire to which the specific POD is connected, the total power threshold would be violated, and in this case it won't activate the specific wiring, that connects

PED to the specific POD. In this scenario, every POD (for which a sensible load is known to be possibly connected) must have a direct wiring which connects it to the PED; such wire is usually not powered (it only allows ID signal exchange) and gets powered with 220/110 voltage, only if consensus is given from PED. In case of PODs which are powered from intermediate junctions, and that have no direct wiring with the master-PED, slave PEDs could be added in the intermediate junctions.

In this scenario, PED must know how much electrical power a POD will absorb, and this information can be statically defined in PED configuration, although it could optionally be self updated as consensus is given (usage statistics) , with an optional time-based reset policy.

A limitation of this scenario is the static load pre-configuration, and the need to direct PED-POD wires, or of intermediate PEDs. The advantage is the limited logic needed in the POD.

EMBODIMENT THREE In a more advanced embodiment, POD, in addition to be able to send its ID (sender) and to receive a consensus signal from PED (CW receiver) , might be also able to remember the last required load from the served appliance.

In this case the amount of power required from each POD may not be known a priori from PED, but PODs are able to remember last used load. PED in this case, must only reply to the given switch ID which made the request, that the requested amount of load is available, as it won't exceed the total available load. So for instance, <ID> and <needed power>, are communicated from POD to PED, and there is no more need of a lookup on a static table.

It's not essential though that this "load-memory" functionality is available inside each POD, and could be also located in the PED itself (keeping track of last power usage associated to each ID, with the optional ability for a time-based auto reset, or a manual reset) . If consensus is not given, an alert (beep) could be fired from the requesting switch.

With reference to Figure 4, the logic flow of an exemplary process that can be implemented in the above-described system to manage the power load (or overload) within a plurality of house appliances is represented with a method 400.

The method begins at start block 401 and passes to block 403 where a new request for power load is detected by the client (POD) 110. The request is then sent to the server (PED) 105 at step 405. The PED processes the request according to a predetermined process and replies to the POD (step 407) . E.g. as described in EP 06127206.8 the expected new requested load could be estimated by the system, e.g. by means of a look-up table by the PED or directly communicated by the POD 110. If the addition of the expected new load to the current one does not exceed the predetermined maximum allowed power of the meter/switch 303 then authorisation is given to POD 110 and supply of power is granted (step 409) and control goes to step 411 where e.g. the circuit is closed by means of a relais; otherwise the control goes back to step 403; in this case alternative recovery solution is implemented (not shown on the diagram) , the request is suspended but the rest of the system does not suffer of any breakdown as with prior art systems. The range of possible recovery solutions is very broad and could be a simple communication to the client (and finally to the user) that the new request is not receivable (e.g. by means of an alarm) or a more complex management of the power load depending on the logic contained in the PODs 110. The control messages exchanged between the PED and the plurality of PODs 110 can be of several different types, depending on the level of complexity of each POD. If the POD 110 is only able to send its unique identity, then the PED will need to directly control the electrical power which has to be granted to the client switch, as the client is not able to receive a consensus signal; this has implications in the electrical wiring, as star-wiring form PED to POD would be needed. On the other hand, if the POD is also able to receive a consensus control signal (e.g. a CW receiver is implemented) , then the set of messages exchanged from PED and PODs could be more complex and PED could avoid a direct control of the electrical power supply to PODs, thus delegating the PODs for the activation of the electrical load, once the consensus signal is issued by the PED. In a further extension, POD 110 may also be able to communicate additional attributes of the controlling load, so that it could be able e.g. to report the expected load demand, according to current load settings or last/historical power demand for the controlling load; this information allows PED to operate in a more dynamic way, without the need of manual power-usage settings for the different controlling client loads. Furthermore more complex recovery actions could be implemented, e.g. one of the currently connected appliances or devices could be disconnected to allow the new request to be satisfied, according to a predefined priority list.

The big advantage of the proposed solution is the fact that the PODs are independent and can be interposed between any appliance and the server (PED) without any need to modify the appliance itself and the wiring system. According to a preferred embodiment of the present invention the PODs can be tuned to a predefined power load which will be communicated to the server (PED) when the corresponding appliance will be switched on (or better when an attempt/request to switch on is detected) . This is not the most flexible solution, as it requires the intervention of a user which also has the responsibility of setting the device to the proper thresholds. On the other hand there is the ease of use and no need of any modifications to the existing systems. For a legacy system this is a substantial advantage. Of course the PODs can be provided with more "intelligence" as required, e.g. it could be possible for a POD to learn the required maximum load of the associated device or to maintain a memory of previously requested loads. From the PED point of view this does not make a big differences as, in any case, what is received from POD is a request for a precise power load and the response by the PED is tailored on this value; accuracy of the system is strictly dependent by precision of the POD request. Another variable which must be taken into account is the information made available by the appliance connected to the POD. Modern appliances could provide a wider range of information which could broaden the possible actions of the POD.

Naturally, in order to satisfy local and specific requirements, a person skilled in the art may apply to the solution described above many modifications and alterations. Particularly, although the present invention has been described with a certain degree of particularity with reference to preferred embodiment (s) thereof, it should be understood that various omissions, substitutions and changes in the form and details as well as other embodiments are possible; moreover, it is expressly intended that specific elements and/or method steps described in connection with any disclosed embodiment of the invention may be incorporated in any other embodiment as a general matter of design choice. Only as an example, the closing of the circuit by means of a relais module, described with reference to step 411 above, could be replaced by other means of controlling the supply of power, once the PED gives its consensus.

Particularly, similar considerations apply if the system has a different structure or includes equivalent servers and/or clients. In any case, the proposed solution lends itself to be applied to scenarios in which PODs 110 are able to report additional information to the controlling PED which could be taken into account when taking the decision; this may include load priority, for possible pre-emption of different active loads, introspection of load setting etc. Similar considerations apply if the program (which may be used to implement some features of the invention) is structured in a different way, or if additional modules or functions are provided; likewise, the memory structures may be of other types, or may be replaced with equivalent entities (not necessarily consisting of physical storage media) . Moreover, the proposed solution lends itself to be implemented with an equivalent method (by using similar steps, removing some steps being not essential, or adding further optional steps - even in a different order) . In any case, the program may take any form suitable to be used by or in connection with any data processing device, such as external or resident software, firmware, or microcode (either in object code or in source code) . Moreover, it is possible to provide the program on any computer-usable medium; the medium can be any element suitable to contain, store, communicate, propagate, or transfer the program. For example, the medium may be of the electronic, magnetic, optical, electromagnetic, infrared, or semiconductor type; examples of such medium are fixed disks (where the program can be pre-loaded) , removable disks, tapes, cards, wires, fibers, wireless connections, networks, broadcast waves, and the like.

In any case, the solution according to the present invention lends itself to be implemented with a hardware structure (for example, integrated in a chip of semiconductor material) , or with a combination of software and hardware.

Alternatively, the proposed method may be implemented on a computer with a different architecture or that includes equivalent units (such as cache memories temporarily storing the programs or parts thereof to reduce the accesses to the mass memory during execution) ; more generally, it is possible to replace the computer with any code execution entity (such as a PDA, a mobile phone, and the like) .

Claims

1. An apparatus (110) for controlling power usage adapted to be connected to an electrical power network system, the system including a server element (105) monitoring the power usage of the system, the apparatus including: first electrical connecting means to connect at least one electrical power consuming element to the apparatus; second electrical connecting means to connect the apparatus to the electrical power network system; means (209) for detecting a start command for the at least one electrical power consuming element, when the at least one electrical power consuming element is connected to the apparatus; means for determining the required amount of electrical power, necessary for the at least one electrical power consuming element; means (203) for transmitting to the server a request for the require amount of electrical power; means (205) for receiving a response from the server; switching means (207), responsive to an authorisation received by the server, to connect the at least one electrical power consuming element to the electrical power network system.

2. The apparatus of claim 1 further including input means (201) for setting a predefined required amount of electrical power .

3. The apparatus of claim 1 wherein means for determining include memory means for storing look-up table containing historical power usage data of the at least one electrical power consuming element.

4. The apparatus of claim 1 wherein means for determining include memory means for storing a unique identifier to be communicated to the server when a request for the required amount of electrical power is transmitted to the server.

5. The apparatus of any preceding claim wherein means for transmitting includes means for transmitting conveyed waves over power lines.

6. The apparatus of any preceding claim wherein means for receiving include a conveyed waves receiver.

7. An electrical adaptor plug including the apparatus of any preceding claim.

8. An electronic device including the apparatus of any preceding claims.

9. A household appliance including the apparatus of any preceding claims.