A new generation of smart plugs to add free connectivity to household appliances v1.0

A new generation of smart plugs to add free connectivity

to household appliances

Valerio Aisa1

1Scientific Advisory, Indesit Company Spa, Via Lamberto Corsi 55, Fabriano (AN), 60044, Italy

(Contact: [email protected] / [email protected])

Abstract The willingness to transform the Energy System into an “enabled smart grid” means a clear change in the

role of major appliances, which must change from being “stand alone” offline tools to real “online networked smart devic-

es”. This improvement in technology requires the appliance to be capable of communicating with the electrical meters for

a more convenient management of the power consumption as well as their transformation into “sensors” to offer elderly

people living alone the possibility to use them for assistance and help. To make those changes real we have to solve some

technical issues related, for example, to the networking technology. These issues are limiting the quick development of the

new phase. For this reason, Indesit Company (a leading European appliance manufacturer) in cooperation with Renesas

Electronics Corporation has developed an innovative low cost networking technology named “Power Modulation”, based

on a new generation of smart plugs. This solution is freely available to all other manufacturers.

Keywords smart appliances, smart grids, smart plugs, smart sockets, smart adapters, energy management, ambi-

ent assisted living, internet of things, low-cost connectivity, power modulation, home automation, application pro-

files, communication standards.

1. Introduction

There are two important worldwide trends that drive the

development of connectivity in the home: the evolution of

the electric grid for improving efficiency, known as "smart

grid revolution", and the need to stimulate the use of tele-

medicine technologies for assisting elderly at home in order

to improve their wellness and independency and at the same

time to reduce social costs. Both of these require the col-

laboration of "smart objects", in particular smart appliances,

which are able to communicate. The necessary communica-

tion infrastructure, mainly based on radiofrequency, can be

the same for both situations (Figure 1). The present paper

shows how household appliances can work both as energy

saving devices and as "vitality sensors" for the elderly,

thanks to a breakthrough communication technology that is

based on a new generation of smart plugs and which doesn't

influence the cost of the appliances.

1.1. Smart grids and Smart appliances.

The growing demand for energy and the absolute need to

reduce climate impact in the world is producing a strong

convergence of scientific, industrial and political interests

towards the use of information and communication tech-

nologies (ICT) to support the process of structural trans-

formation of each phase of the energy cycle: from genera-

tion to transmission, from distribution to sale, to accumula-

tion and, above all, to the smart consumption of energy.

This valuable link between ICT and the world of energy is

commonly identified with the term Smart Grid. Therefore,

within the concept of Smart Grid there is the need to collect

and process in real time information generated by appropri-

ate measuring devices and sensors, distributed on the net-

work in order to achieve a coordinated control of different

parts.

There is also the need to encourage a more active role of

the end users in the industrial sector and especially in the

residential sector, aimed at stimulating - through appropri-

ate levers of economic convenience - a more careful and

collaborative participation in the management of energy

consumption to reduce peaks through the leveling of power

absorption profiles [1]. In both cases the creation of ade-

quate communication infrastructures [2,7] associated with

the distribution network is thus essential.

1.2. Ambient Assisted Living and smart appliances.

The average lifetime of the population is increasing eve-

rywhere, thanks to the achievements of medicine and the

work to prevent disease that most countries have been pur-

suing for some time. This fact is positive but, nevertheless,

causes an aging population of the planet and generates so-

cial costs, with the consequent need, for the governments of

most developed countries, to create the necessary condi-

tions for citizens to keep their autonomy and independence

in their own homes for as long as possible, at the same time

reducing healthcare costs.

Figure 1. Main drivers to add connectivity to household appliances.

One of the most effective ways to meet these needs is by

encouraging the use of telemedicine to assist the elderly in

their homes, aimed at maintaining a high quality of life and

drastically reducing the need for hospitalization.

The research activities of Indesit Company highlighted

how household appliances (which are able to communicate)

can play the role of "sensors of the vitality" of the user

(Figure 1), able to monitor his/her daily interactions with

the appliances - the opening of the doors of the refrigerator,

for instance - to infer his/her habits and report any unusual

behavior that might occur in connection with situations of

hardship or danger for the user.

2. Indesit's past experience in smart ap-pliances

Indesit addressed connectivity for the first time about 25

years ago, when President Vittorio Merloni conceived

ArisionTM, the "digital butler" able to speak and control the

home, born in 1985 in Merloni Elettrodomestici (Indesit

Company since 2005). It was the first device able to enter

into a relationship with the household by using voice mes-

sages.

The experience of Arision was a strong stimulus for the

future commitment of the Company in introducing digital

technology into the control systems of household appliances,

with the aim of giving the products a greater versatility and

"intelligence".

2.1. Birth of Margherita DialogicTM (1995).

The aforementioned commitment began to show the first

results in the second half of the '80s, with the first digital

products for cooking and refrigeration, but found its full re-

alization in the '90s, when Vittorio Merloni decided to

launch the ambitious project - at that time really very inno-

vative for the white goods industry - to acquire all the skills

necessary for autonomously developing digital control sys-

tems for its products.

From this project Margherita Dialogic (1995) was born,

the first digital washing machine capable of communicating

with the surrounding environment, and then (1997) the be-

ginning of Indesit relationship with Enel, the big Italian

utility, aimed at optimizing the energy consumption of the

home through the dialogue of the household appliances

with the new digital electricity meter (under development at

that time).

2.2. Ariston DigitalTM and Leon@rdoTM (1999).

The interaction with Enel, Echelon1 and the Massachu-

setts Institute of Technology (MIT) of Boston allowed the

Company, under the strong commitment of Francesco Caio

(CEO, at that time) and President Vittorio Merloni, to de-

vise and implement Ariston Digital (1999), the first system

of household appliances (Figure 2) capable of communi-

cating (using LonTalk protocol) with each other and with

the outside world through Leon@rdo (Figure 3), the first

"Internet appliance" dedicated to the kitchen.

Figure 2. Ariston Digital, the first system of connected household

appliances (1999).

Figure 3. Leon@rdo, the first internet appliance for the kitchen (1999).

2.3. Margherita2000.comTM (1999) and Margherita

Pay-per-Use TM (2002).

Through the Ariston Digital experience - characterized

by the great success of Margherita2000.com (Paris, De-

cember 1999, see Figure 4), the first appliance capable of

communicating with a mobile phone and of interacting with

the web, and then the success of Margherita Pay-per-Use

(2002), the first washing machine in leasing, where the user

1 Echelon (Palo Alto, CA), leader in the field of data communication, was partner

of Enel in the project for developing its new electricity meter.

didn't buy the product but just its service -, the Company

gained international credit and visibility.

Figure 4. Margherita2000.com, the first washing machine controllable

through a cellular phone or a PC (1999).

2.4. Energy@home project (2009).

After this experience, Indesit was able to start playing an

active role in CECED [4] - the European organization of

manufacturers of home appliances - with the opportunity to

effectively contribute, along with Electrolux,

Bosch-Siemens, Whirlpool, Miele and other manufacturers

of white goods, to the development of common communi-

cation rules to ensure interoperability between products of

different brands [5,6].

It was a long standardization process which in recent

years has found its first important concretization with the

recent project named Energy@home [7] - sponsored by

Enel and developed in collaboration with Telecom Italia and

Electrolux - which officially started in October 2009 and

which will finish by the end of 2012.

The goal of this project is to define, develop and make

available all the hardware and software components re-

quired to minimize the cost of electricity and reduce CO2

emissions through an appropriate dialogue between the

household appliances and the digital energy meter, and to

open the home to the world of new web based services

(Figure 5).

The dialogue between the electric utility and the house-

hold appliances is based on a new device of Enel’s called

Smart Info (SI), which has access via PLC (Power Line

Communication) to all the data generated by the electricity

meter and can benefit from a broadband internet connection

made available by Telecom Italia through its new Home

Gateway.

Figure 5. Energy@home global architecture.

The local network HAN (Home Area Network) is based

on radio frequency and employs low power ZigBee tech-

nology [3]. The ZigBee based communication node, which

is located within each element of the system (Smart Info,

Home Gateway, appliances, smart plugs, smart sockets...),

has a new "application profile", currently being developed

by the four partners of the project. This new profile incor-

porates the results of many years of work, aimed at ensuring

interoperability between products of different brands, which

was carried out by CECED during the first half of the pre-

vious decade and recently standardized by CENELEC [5,6],

and its purpose is to complement the preexisting profiles

Smart Energy (SE) [8,9] and Home Automation (HA) [10]

of ZigBee protocol. It incorporates and extends the features

of earlier SE and HA profiles in order to give to each ap-

pliance the full potential that comes from its new role as an

"intelligent" element of a home automation system, and it is

technically configured as an extension of the same "ZigBee

Home Automation profile" (addition of appropriate new

clusters to HA profile), expressing the results of many years

of experience on connectivity issues of European manufac-

turers of household appliances.

Indesit has recently joined the ZigBee Alliance [3] and is

making a great effort, supported by strategic alliances

[11,27], towards the aim of reducing the time-to-market of

its "intelligent" products.

3. Problems for connecting white goods

The great pioneering effort made by Indesit in the mid

90s, appreciated also internationally [12, 13], could not be

finalized to the market for the following three main reasons:

the total lack at that time of communication rules

shared by the various manufacturers of white goods,

the almost total absence in homes of broadband (In-

ternet penetration in the home relates to recent years and is

still in progress)

and, last but not least, the excessive cost of the con-

nectivity.

While the first two problems will be completely solved,

the third one remains a barrier to the spread of connectivity

for mass products: although there will be, day by day, tech-

nical solutions with more affordable costs (such as

ZigBee-based communication nodes, for instance), never-

theless the introduction of a communication node inside an

appliance still causes considerable "side effects".

3.1. First problem: tying household appliances to a spe-

cific communication technology can be risky and expen-

sive.

A first obstacle comes just from the presence of a com-

munication node within a product, tying it to a specific

communication technology. This is risky, because it requires

frequent updates to the product caused by the natural evolu-

tion of the adopted protocol. In fact, the need to update the

product would be a great burden for the user, because it re-

quires the presence of specialized technicians, and it is very

unusual for the white goods field.

3.2. Second problem: household appliances with a

communication node inside can be sold only through

specific channels.

A second problem is the cost of the communication node

which, placed inside a household appliance, increases its

industrial cost and decreases its competitiveness. This cost

is increased also by the need to introduce mechanical

(hardware), electrical (extra wires) and electronic changes

to install the communication node. As a consequence of this,

it is substantially impossible to sell products with a com-

munication node inside using traditional distribution chan-

nels.

The use of a communication node on board may be use-

ful in the case of high-end products, where specialized dis-

tribution channels are used.

3.3. Third problem: too much time is needed to replace

all the household appliances already installed in the

houses.

A third problem, which concerns the "home system" and

refers to the management of electricity consumption ac-

cording to the concept of the smart grid, is that the time re-

quired by the new generations of smart appliances to re-

place all the products currently present in the houses is

about ten or more years, so it is too long to properly support

the parallel development of the new electricity networks.

This leads us to seek new solutions to accelerate the de-

ployment of appliances which are able to collaborate with

electric utilities and to support new value added services.

3.4. Power Modulation (PM)2, the communication tech-

nology developed by Indesit to solve the previous prob-

lems.

The above mentioned problems have suggested, since the

early 2000s, the exploration of other paths in addition to the

classical solution represented by a "communication node"

inside the household appliance, and Indesit Company de-

veloped and successfully tested a technical solution that is

very cheap and absolutely adequate for managing the ener-

gy issues coming from the smart grid's opportunities [14],

and much more.

This solution is called “Power Modulation” (PM) and,

thanks to the strong support of the University of Parma, it

has been implemented on silicon [15,16,17,18,19] by

Renesas Electronics Corporation (the Japanese Company

2 PM Technology is property of Indesit Company Spa

(www.indesitcompany.com). Its technical support for producers of smart plugs

and household appliances has been totally delegated by Indesit to SPES

(www.spesonline.com).

founded by Hitachi, Mitsubishi and NEC), creating a pe-

ripheral device for microcontrollers named PMI (Power

Modulation Interface). After the signing of a free license

agreement (March 29th, 2010) between Indesit and Renesas,

the Indesit PMI peripheral device has been added by

Renesas to a new family of 32 bit microcontrollers dedicat-

ed to smart appliances. In such a way, the low cost commu-

nication technology of Indesit is now freely available,

through Renesas RX210 microcontroller family3, or other

similar microcontrollers4, to all manufacturers of electrical

household appliances that want to use it.

3.5. Main features of PMI, a peripheral for microcon-

trollers dedicated to smart appliances.

PMI (Power Modulation Interface) is an LSI that incor-

porates PM technology to enable serial data communication

using the power supply cables of home appliances. When

combined with a smart adapter (SA), or an interface be-

tween home appliances equipped with the PMI module and

house power wall outlets, the PMI provides a home net-

working system that connects various home appliances by

using general AC power lines used in a house.

Furthermore, the PMI peripheral device has three other

important functions: the Dynamic Demand Control (DDC)

feature to support smart grid needs; a rigorous measurement

of mains voltage (+/- 2%) to improve the performance of

the appliance (capability to adapt its working cycle to opti-

mize energy consumption); an early recognition of a power

failure to avoid losing data related to the working status of

the appliance, a very useful function that helps designers of

digital control systems for household appliances to safely

manage power failures.

3.6. Dynamic Demand Control (DDC).

Recent trials based on an old concept proposed in 1979

by Prof. Fred. C. Schweppe of MIT (Boston, USA) are

showing how it is possible to contribute to the stability of

the electric grid through the synergistic and synchronized

action of digital appliances capable of continuously moni-

toring the value of the mains frequency [21]. This is the

concept of "Dynamic Demand Control" (DDC) [22-24], i.e.

the possibility that a set of domestic appliances distributed

over a large geographical area (maybe an entire country like

the UK or Italy) and synchronized through the same fre-

quency, can act in a synchronous manner to transfer or ab-

sorb power when the mains frequency, respectively, tends to

fall below a certain threshold lower than 50 Hz or to rise

above a certain threshold greater than 50 Hz (Figure 6).

In this way the joint and synchronous action of thousands

of appliances produces, through the sum of the small con-

tributions of electrical power from each one, corrective ac-

tions which make it possible to ensure a substantially stable

balance between the power generated by the power plants

3 For more info about Renesas RX210 microcontrollers family, please contact

Mr. Massimiliano Mazzoni ([email protected]). 4 The PMI peripheral, owned by Indesit, is freely available for manufacturers of

microcontrollers that want to use it inside their products. For more info, please

contact Valerio Aisa ([email protected]).

and that absorbed by the downstream users, minimizing

or even eliminating the costly interventions upstream

(switching on of generators for meeting the increased de-

mand for power, or putting them in standby mode when

there is an excess of production) which cause great ineffi-

ciency and increased harmful emissions to the environment.

Appliances which are best suited to performing this func-

tion are refrigerators, water heaters, and HVAC systems, i.e.

those products that have a thermal accumulation (hot or

cold) which allows them to manage the DDC function, pre-

serving the quality of their performance in any working

condition.

Figure 6. Dynamic Demand Control based on mains frequency.

The DDC function is considered very important in some

countries like Europe and USA, where trials are under way:

the presence inside the PMI peripheral of a precise grid

frequency meter, which is capable of signaling via "inter-

rupt" situations where this frequency falls below a certain

threshold or rises above another threshold, represents a

great opportunity to develop "DDC enabled" appliances,

which can help to restore the balance between the power

available on the grid and the power absorbed by the various

electric users connected to it.

This feature can be effectively used in refrigerators, wa-

ter heaters and HVAC devices, that are capable of tolerating

brief reductions of their power consumption. Indesit is

presently supplying Fridges for a DDC trial in the UK,

supported by RLtech, NPower and the UK Government.

3.7. Liberalization of Power Modulation through a new

generation of low-cost 32 bit microcontrollers dedicated

to smart appliances.

The liberalization of PM (on March 29th, 2010) allows

any manufacturer of household appliances to use it without

paying any royalty: therefore it is expected that this oppor-

tunity will speed up the diffusion of smart appliances.

Indesit decided to share its patented technology with its

competitors in order to open the market of connected ap-

pliances.

3.8. The new generation of washing Machines produced

by Indesit Company will be based on "power modula-

tion" technology.

Indesit is promoting PM by applying this technology on

the new generation of its products. In particular, Indesit top

management has officially planned to use Renesas (PMI

based) RX210 microcontrollers for the next platform of

washing machines, presently under development, which

will be on the market from 2014 (about four million pieces

per year).

4. Introduction to Power Modulation (PM) technology

PM Technology has the aim of adding point-to-point5

communication capability to a household appliance without

affecting its industrial cost, because it uses the same elec-

tronic resources already present in it.

To do this, the appliance should have a control system

based on a microcontroller and at least one electric load

controlled through a triac (T1, Figure 7).

The basic concept of PM is transmitting data by modu-

lating the power absorbed by one of its low power electric

loads. In this way, it is possible to transmit 50 or 60 bit per

second, depending on the mains frequency, i.e. 6 or 7 bytes

of coded data per second [15,16].

At first sight, this kind of transmission with such a lim-

ited baud rate seems to be too limited, but actually covers

perfectly what is necessary to satisfy all the needs related to

energy and healthcare issues and much more. In fact, to

transmit the status of the appliance, or some other infor-

mation like a time interval, a temperature, statistical data,

diagnostic data, fault codes, and so on, only few bytes are

necessary.

Furthermore, PM communication is bidirectional: the ap-

pliance can receive 25 or 30 bytes per second, depending on

the mains frequency. This means the appliance can receive,

for instance, commands and information through a local

network from an energy manager placed in the home; and,

in turn, it can send, day by day, statistical and diagnostic

data to a remote service centre which offers the customer

high level services like remote assistance and preventive

maintenance. For more details about PM technology, please

see the referenced documents [16-20].

4.1. The new role of smart plugs (smart adapters).

In order to connect a "PM enabled" household appliance

to a local network, a special adapter (commonly called

“smart adapter”) placed between the appliance power cable

and an electric socket is needed.

The “smart adapter” is simply a “smart plug” with a

power meter, a proper logic for decoding the data sent by

5 PM Technology is a point-to-point communication that allows a household

appliance to directly communicate with a proper “smart plug” or “smart socket”

that provides its power supply (from the mains) and the connection to a local

network.

the appliance, and means for its connection to a local net-

work (any LAN technology can be used). It can also be in-

tegrated inside a socket, so creating a “smart socket”.

Thanks to Renesas Electronics Corporation and the Uni-

versity of Parma [15-20], PM technology was embedded

inside a microcontroller peripheral device (named PMI,

Power Modulation Interface) in order to guarantee repeata-

bility of the data transmission from the household appliance.

For this reason, Indesit is today able to offer the license of

PM technology to any interested manufacturer of “smart

plugs” and “smart sockets” to develop a new generation of

devices that can interact with the grid and, at the same time,

are able to communicate directly with the household appli-

ances that receive AC power supply through them.

Smart plugs of the latest generation (Figure 8) are actu-

ally able to measure the energy consumption of the related

appliances and to share such data with proper energy man-

agement systems. They can also switch off the appliances

through a relay, when necessary.

However, using smart plugs with on/off control is con-

sidered unacceptable, for several reasons (mainly for safety

issues) [25], by white goods manufacturers and consumers,

because such plugs typically don't know the working status

of the related appliances and can cause malfunctioning or

inefficiencies.

A good way to overcome this limitation is to inform the

smart plug about the working status of its appliance to al-

low them to interrupt the power supply only when this ac-

tion doesn't cause problems: this communication can be

made directly by the appliance itself thanks to PM technol-

ogy.

4.2. PM can promote a new generation of smart plugs.

Smart plugs of the latest generation (Figure 8), that are

able to communicate energy data to a local network, are al-

so suitable for adding PM communication, because it can be

easily implemented inside a traditional “smart plug” just by

adding the proper logic (software) to decode the data sent

from the household appliance through the PMI peripheral

device of Renesas RX210 microcontrollers.

In practice, to add PM technology to a traditional

"smart plug", it is necessary to perform the following

two operations: insert proper logic to decode the data

sent from the appliance and add proper hardware to send

data to it.

Depending on the type of modification, we can have

two different solutions: the simpler one that is based on

the unidirectional use of PM, and the second one based

on the bidirectional use of the same communication

technology. In the first case, the appliance communicates

to the smart plug its working status, the events of inter-

action with the user (for healthcare applications) and

other information useful for assisting the product re-

motely; in the second case, the appliance can send data

and receive commands, working as a smart appliance

suitable for communicating with smart grids and for of-

fering web based services.

4.3. How a smart plug can monitor the status of the

controlled appliance.

Digital appliances (based on PMI microcontrollers) can

periodically send information about their operating status

(and many other data ...) by modulating the power absorp-

tion of one of their triac controlled electric loads. Smart

plugs can capture the information about the working status

of the related appliance by properly decoding the fluctua-

tion of the power absorbed by it, and then decide to open

the relay contact (switch off) only if the appliance agrees.

To do this, the smart plug needs a power meter and proper

software to decode the digital data sent by the appliance.

Figure 7. PM communication system: (a) smart adapter, (b) digital household appliance.

4.4. Benefits for the appliance makers

White goods makers can sell PM enabled products with

greater margins than standard ones, because these products

have new potentialities based on a free connectivity that

justify a major price. Of course, a PM enabled product pro-

duces greater margins than a standard one, if its potentiali-

ties are well presented; furthermore, it opens the white

goods market to new business opportunities coming from

the offer of value added services based on the web.

Other benefits are:

PM adds two-way connectivity at no cost to a standard

appliance (provided with a digital control), useful for con-

necting it to a local network for various purposes: energy

management, remote assistance, monitoring and control of

the appliance, monitoring of the user's daily behavior, and

so on. As an alternative to this approach, it should be nec-

essary to put a "communication node" inside the appliance

with a considerable cost (depending on the type of the

adopted communication technology), causing an increment

of the global cost of the appliance. Therefore, an appliance

with a communication node inside cannot be sold through

normal distribution channels, but needs dedicated ones.

PM avoids tying an appliance to a specific communi-

cation technology through a "communication node" (stand-

ard or not) located inside the appliance itself, because it

moves the node from the appliance to an external device

(smart plug / smart socket): this makes it possible to elimi-

nate the cost of the node from the appliance, avoiding the

difficulties/cost of inserting and testing the node during the

production of the appliance, and the need for frequent and

expensive updates of the communication protocol. While an

appliance with a communication node inside can be used

only with a home system that uses the same communication

technology, a PM enabled appliance can be connected to

any local network, just using the "smart adapter" compati-

ble with the desired local network.

PM dramatically simplifies the tools necessary for

testing an appliance during its production and also reduces

the testing time, because it is possible to send commands

directly to the appliance through its power cable to switch

ON and OFF each internal electric load, measure its ab-

sorbed power (through the "smart adapter") and compare

the measured data with reference values. Therefore the

testing tools become simple and cheap, the testing time is

reduced and consequently the cost of the testing process

decreases.

Figure 8. Smart Plugs, the retrofitting devices for traditional household appliances?

PM allows a standard appliance to work as a peripher-

al device of any home automation system (via a smart

plug/socket) without adding cost to the product. Producers

of home automation systems consider interacting with PM

enabled appliances through proper smart sockets to be very

important, because it is a very simple and cheap way to

include standard household appliances in their system.

PM is adaptable to any standard application profile

(e.g.: smart energy SEP1.X, future SEP2.0, Zigbee home

automation profile improved with Energy@home results)

and to any protocol (Zigbee, Z-Wave, WiFi, Bluetooth,

Konnex, LonTalk, HomePlug AV, ...). Unlike an appliance

with a communication node on board (that can be connected

only to a local area network compatible with the technology

of that node), a "PM enabled appliances" can be connected

to virtually any local network, simply by using the smart

adapter compatible with that network.

PM is suitable for AAL (Ambient Assisted Living) ap-

plications where a PM enabled appliance, working as a "vi-

tality sensor" of an elderly user who lives alone, can be as-

sociated with any system of telecare/telemedicine. There-

fore a PM enabled appliance can also work as a "vitality"

sensor for the elderly.

4.5. Benefits for the final consumers

The main benefits come from this fact: the consumer

buys a household appliance open to the future and he pays

for a standard product. The expression "open to the future"

means the possibility to connect the product to any future

home network related to systems offering new services, that

the consumer will decide to buy when he wants. In other

words, an inexpensive PM enabled appliance has commu-

nication potentialities that can be used when the consumer

wants, over time. To connect the appliance to a home net-

work, the consumer will use a proper smart adapter, select-

ed according to the type of local network adopted for a spe-

cific application.

Possible applications are:

Energy management (requires the presence of an en-

ergy management system).

Energy monitoring (monitoring of the energy con-

sumption of the appliance).

Home automation (the system can monitor the work-

ing status of the appliance).

Remote control through the internet (the consumer can

remotely control the appliance, when applicable).

Ambient Assisted Living applications (applications for

helping the elderly in daily life).

Application for smart phones or smart tablets that al-

low the consumer to interact with his PM enabled applianc-

es.

Applications that improve consumer awareness on en-

ergy consumption, thanks to the nature of PM which means

the presence of a power meter.

4.6. Main features of Power modulation (PM)

Summarizing, the main features of PM technology are the

following:

No cost for the manufacturer of household appliances,

because the communication is managed by the same control

systems of the appliances, based on PMI microcontrollers,

like the Renesas ones (new 32-bit RX210 family). Further-

more, after the signature of a free license agreement between

Indesit and Renesas (March 29-th, 2010), no royalty is due to

Indesit for using PM enabled microcontrollers supplied by

Renesas.

No need to tie the appliance to a specific network pro-

tocol, because the connection to a local network is managed

by the “smart adapter”. In other words, the communication

node (necessary) is moved from the appliance to the smart

adapter, and all the networking issues are managed by this

adapter. Therefore, PM technology is compatible with vir-

tually any network protocol.

Fully suitable for interacting with a smart grid, because

PM technology is able to manage all the necessary infor-

mation.

Enabler of the role of "vitality sensor" for a household

appliance.

Capability to perform the energy function called Dy-

namic Demand Control easily [21-24], because the same

PMI peripheral of Renesas RX210 microcontrollers provides

a precise measurement of the mains frequency and compares

it with a programmable threshold.

Very easy to implement: thanks to microcontrollers

with PMI peripheral on board, like the Renesas RX210

family, dedicated to “energy-aware” household appliances.

Capability to speed up the diffusion of smart appli-

ances. The availability of a new generation of "smart plugs",

which thanks to PM technology are capable of communi-

cating with their electric appliances, makes it possible to

speed up the diffusion of smart appliances interacting with

the grid.

Compatible with a standard “communication node”6,

because the control system of the appliance can easily

manage the two different communication channels.

Suitable for supporting a new generation of “smart

plugs & smart sockets”, connectable to any local network

and able to communicate directly with the related household

appliance.

Suitable for remotely assisting household appliances

without adding any cost to the product. It is possible because

the new generation of household appliances based on

Renesas 32 bit microcontrollers (RX210 family) can execute

complex routines for auto-diagnosis and will be potentially

able to capture early symptoms of possible faults – with the

help of proper sensors - to enable preventive maintenance

services.

Simpler and shorter in-line test of the appliance, with-

out the need to use expensive and complex tools. In fact,

thanks to the “power metering” function of the “smart

adapter”, it is possible to send to the appliance, for instance,

commands for sequentially activating and deactivating each

electric load of the appliance, at the same time measuring its

electrical quantities like the absorbed current and the cosphi

(displacement between the mains voltage and the mains

current related to the electric load).

4.7. Indesit strategy on connectivity.

As already mentioned, Indesit is partner of the important

project named Energy@home [7], along with Enel, Electro-

lux and Telecom Italia, and intends to base its strategy for

connectivity on Zigbee technology and its approach is two-

fold:

Using Zigbee technology in high-end products, fol-

lowing the general trend worldwide based on appli-

ances with a communication node on board.

Adopting PM for the entire production of digital ap-

pliances (including high-end products): in this case

the Zigbee based communication node is placed in-

side the smart plug (smart adapter).

5. Conclusions

Power Modulation (PM) - a simple and very cheap

communication technology developed by Indesit over the

6 A white goods manufacturer can use PM technology as the basic communica-

tion system for the entire production of digital household appliances, because it

doesn’t cost. When a higher rate communication is requested (case of high end

products, for instance), a standard communication node can be added without any

problem.

last decade to overcome the obstacles encountered in at-

tempting to produce “smart appliances” for the connected

home - has good potential to become a "de facto" standard

able to transform traditional household appliances into

smart ones without increasing their industrial cost.

PM allows an electric appliance to exchange data with

local networks through a new concept of smart plug, capa-

ble of working as a network-adapter to avoid a direct

connection (risky and expensive) of the appliance to a do-

mestic LAN.

Indesit has decided to liberalize PM to speed-up the dif-

fusion of "smart appliances" to support the smart grid revo-

lution and to make it possible to offer telecare and other

web-based services. Such liberalization is based on micro-

controllers with a PMI peripheral inside, presently produced

by the Japanese Renesas Electronics Corporation and, in the

next future, by any other manufacturer of microcontrollers

that can be interested in this technology.

ACKNOWLEDGEMENTS

The author would like to thank Mr. Yoshinori Suzuki

(Group Manager MCU Design Dept. 5, MCU Systems Di-

vision, Renesas Electronics Corporation), Mr. Terukazu

Watanabe (Associate General Manager, General Purpose

MCU Systems Division, Renesas Electronics Corporation),

Mr. Norishige Kawashimo (General Manager, General

Purpose MCU Systems Division, Renesas Electronics Cor-

poration), Mr. Graeme Clark (Product Marketing Manager

at Renesas Technology America Inc./Europe Ltd), Mr. Andy

Harding (Digital Home Business Group Manager, Industrial

Business Group, Renesas Electronics Europe), Mr. Vincent

Mignard (Marketing Manager for white goods and motor

control at Renesas Electronics Europe), Mr. Enzo Della

Calce (former Country Manager, Renesas Technology) and

Mr. Massimiliano Mazzoni (OEM Sales Manager, IBG Italy)

for their decision to adopt "power modulation" and their

strong support to this work.

Many thanks also to Prof. Paolo Ciampolini of the Uni-

versity of Parma, which has allowed the realization of the

PMI (Power Modulation Interface) peripheral for micro-

controllers, and to Dr. Andrea Ricci which has designed it

during his PhD experience.

A special thank to Andrea Merloni, President of Indesit

Company SpA, for his decision to liberalize PM technology

in cooperation with Renesas Electronics Corporation, and,

with him, to Mirco Astolfi (Electronic Division Manager,

Indesit Company), Stefano Frattesi (Technology Center

Manager, Indesit Company), and Adriano Mencarini (for-

mer Director of Innovation & Digital Design, Indesit Com-

pany).

Many thanks and great gratitude also to Enrico

Smargiassi and Daniele Barbini, President and CTO of

ELITE, and to Davide Mancini, Franco Boldreghini and

Mauro Angelini, respectively CTO, President and Market-

ing & Sales Director of SPES, for their determinant con-

tribute in implementing and supporting PM technology.

Finally, the author wishes to express his gratitude to his

friend Dr. Arturo Colantuoni Sanvenero (former Vice Pres-

ident Marketing, Sales and Innovation at Indesit Company

Spa during the development of the Ariston Digital system,

and later European Commercial Director Integrated Home

Solutions at Whirlpool Corporation) for the patient revision

of this article, for his valuable advice and for what done in

the past to support the development of the above mentioned

networking solutions.

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Downloads: http://www.slideshare.net/vaisa1