datasheets.com EBN.com EDN.com EETimes.com Embedded.com PlanetAnalog.com TechOnline.com  
Events
UBM Tech
UBM Tech

Design Article

Enabling next gen smart utility meters

Milen Stefanov, Texas Instruments Inc.

10/2/2012 11:24 AM EDT

1.1 New wM-Bus mode for smart gas, water or heat meters
In alignment with ETSI 300220v2.3.1, a new “N”-mode physical (PHY) layer has been introduced within the latest draft of EN13757-4:2011 (also called wM-Bus) document. The 75 kHz bandwidth has been split into 6 narrowband channels of 12.5 kHz each. Four channels of 4.8kbps with GFSK and two at 2.4kbps with GFSK modulation have been defined.

A secondary communications link, capable of 19.2kbps with 4-GFSK modulation, has been defined with the purpose of optimizing data throughput in optional multi-hop links (Figure 2).


Figure 2: wM-Bus mode N (as per EN13757-4:2011 draft document)

Field tests with 169MHz systems in France have already proven that the longer achievable range leads to significant simplification of the network architecture. With the proper deployment of data collectors at 169MHz, smart grid networks in Europe without repeaters become a realistic scenario.


Figure 3: wM-Bus N-modes and ETSI 300220v2.3.1 relationship (Source: EN13757-4:2011 Draft)

The new wM-Bus N-mode is explained in Figure 3; this 169MHz narrowband solution is well suited to become the choice for future gas and water meter installations in several European countries.




WKetel

10/3/2012 9:18 PM EDT

I see a whole lot of discussion about the technology for the communication with the smart meters but only a small amount about how this is going to save enough energy to be worth the effort. Of course, the very first use will be to raise prices a lot just when everybody wants power the most. We all know that is the primary goal of the two way system. The other goal is to eliminate the expense of manual meter reading, which will reduce the utilities costs quite a bit, but will not reduce our price for power at all.
The way to eliminate all of the privacy concerns is to keep the specific minute-by-minute consumption data in the meters, and to just totalize the product of KWH and the rate at the time of consumption. Then the utility could poll the meters to determine the charge for that month's power. No customer information except for the total charge would ever need to be sent out, just as in the past when meters were manually read. The utility has no need of individual household consumption at any particular time, only block by block, or subdivision by subdivision. The assertion that they need to know the individual rate of use at any particular instant is not valid.

Sign in to Reply



GPBobby

1/18/2013 11:06 PM EST

Data is only useful to the extent that it can alter some outcome, in this case, a customer's use of electricity. Almost no electrical customer even knows that their new smart meter is capable of turning off their power. The above article states, "to enable utilities to ease peak power demand..." where ease should be read as: a) a total disconnect; b) a rolling brown out; c) by interfacing with your own personal in home network to turn off selective appliances such as A/C, dryers, heat pumps or any other device which has built in communication capability.

I can see a small business in modifying newer appliances (if possible) to make sure they cannot communicate. The polite way to modify power consumption is to let the consumer know (by checking an Internet site at their convenience) their current charge per kWh. Then let them decide what devices to turn off.

Sign in to Reply



pekon_

1/24/2013 11:42 PM EST

But if this was so lucrative, then why did google retired their power-meter service ?
http://www.google.com/powermeter/about/

Its just that there isn't enough eco-system built around to manage|optimize energy. And also its usage is expensive.

Many companies have smart-metering products from long, but lack of government urgency, and tough norms are also pulling this market low.


[pekon]

Sign in to Reply



GermanInTI

2/27/2013 4:46 PM EST

Not only MCU but also memory is a key factor for smart utility meters. TI is somehow leading the MCU part but not the memory, suprisingly even having a great technology called FRAM in Texas. FRAM makes the meter design extremely simple and flexible. Fujitsu and Ramtron leads the memory market for smart meters with FRAM. TI wake up...

Sign in to Reply



Please sign in to post comment

Navigate to related information

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)