GEMAC - Gesellschaft für Mikroelektronikanwendung …Streaming of gaseous and liquid substances (i.e. industrial mill, flow meter) ... Working principle (conversion of physical values

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GEMAC - Gesellschaft für Mikroelektronikanwendung Chemnitz mbH

Innovative Low Power Electronics for EnergyAutonomous Transducers: Pressure

Sensors, Inclinometers, Accelerometers andVibration Sensors

Dipl.-Ing. (FH) Dirk Hübner

Hannover 07.04.2011


Why energy autonomous?

Increasing material and energy costs

Trend to preventive monitoring of technical installations and processes

Sensors at critical points of applications

Increasing installation effort

Demand for unlimited life time

Intention:

Simple and flexible sensors with an autonomous power supply and data transmission


Fields of Application

Tire pressure sensor

Medical technology

Building automation (switches) ‏

Condition monitoring

Mobile machines


Why energy autonomous and GEMAC?

GEMAC products

Sensors for inclination, acceleration and vibration

Interpolation circuits

Field bus tester

Length measuring systems


Energy Autonomous System - Structure


Energy source

Physical principles:

Temperature difference (i.e. thermo-electrical generators) ‏Light (i.e. photovoltaic power plants, solar cell, solar thermical plants) ‏Mechanical vibration (i.e. piezo-electrical or electro-mechanical) ‏Streaming of gaseous and liquid substances (i.e. industrial mill, flow meter) ‏extension, compression, pressure (i.e. actuation) ‏Battery


Energy source - Problems / Challenges

In all cases mentioned energy is available in limited quantitiesand/or limited time.

How is it possible to generate as much energy as possible?

How can energy be stored most effectively?


Example: Vibration Generator

Energy harvesting by a coil-magnet-arrangement

Energy efficient rectifier replacing the full bridge rectifier with a NMOS-rectifier

Energy storage through battery or super-cap

e.g.: vibration generator from HSG-IMIT developed in the project IEKU supported by BMBF

Energy source

Generator

Rectifier

Energie storage


Sensor Electronic

How can the sensor information be processed and transmitted in the most energy efficient way?

Energy analysis of each step necessary


Capability influences on the sensor electronic

Sensors

Working principle (conversion of physical values to electrical signals) ‏

Number and complexity of parts for external sensor circuits

sample rate

signal conditioning

ADC

Working principle

sample rate

Micro controller

clock frequency

Architecture and Periphery


Energy analysis

87,0%

6,6%4,6%0,6%1,2%

Energieverbrauch IEKU

Initialisierung Senden MessungRuhe Rest

Main problem of energy - autonomous systems is the limited energy (time and volume) available.Therefore an exact analysis of the energetic operation within the system is necessary.

e.g. energy autarkic pressure sensor for automotive applications

Biggest energy sink is initialising of the wireless radio module

e.g.: pressure sensor for automotive application

High energy demand for Initialization of the wireless module


Energy analysis

Hardware component selection and optimizing (based on energy analysis) ‏

components with a minimum of power loss in dependence on target application

Microcontroller

ADC

Wireless radio module wireless technology selection (WLAN, Zigbee, Bluetooth, NanoNet)‏

Positive effects of using an optimized hardware:

Increased measuring accuracy and reduction of measuring time

Usage of efficient components for power supply with minimum input voltages

Minimization of PCB area


System Electronic


Firmware

Usage of special working modes such as „sleep“ or „power-down“

Testing of methods for initialization

Function reducing

Intelligent solutions for energy efficient data processing

Consideration of safety aspects

Active adaption to existing energy


Firmware

0 10 20 30 40 50 60 700

2

4

6Generatorspannung

Volt

0 10 20 30 40 50 60 70Aus

Ruhe

Messung

ÜbertragungFirmware - State

0 10 20 30 40 50 60 700

2

4

6Kondensatorspannung

Sekunden

Volt

Beispielhafter Programmablauf mit dynamisch angepasstem Sendeintervall


Firmware


Data Transmission

Methods for data transmission:

By wire Wireless radiooptical

Energy Source

Energy ConverterEnergiy Storage

Sensor electronic(Sensor, ADC, µC,..)

Wireless Data TransmissionTransmit / receive


Data Transmission

Requirements for the data transmissionHigh reliability

High availability

Less demand on energy

Application specific range of operation

Application specific data transmission rate

Conflict as not all requirements can be met

Therefore application specific adaptation necessary

Pulse mode,…


Advantages / Disadvantages Wireless RadioAdvantages

High flexibility

Low costs

New fields of application

Information availability in a wide range

Disadvantages / Main problems

Usage of primary batteries impossible

Energy demand is too high resp. energy supply is not sufficient

No optimal wireless standard for special applications available


Wireless Data Transmission

Optimized wireless driver stack effects:

High data transmission safety

Low energy demand

Wide transmission range

Possibility of using different numbers of sensors within a network


PSP A/021272

Sensor module

Logic moduleWireless radio module

Customized solution


Energy balance

-0.005 0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.040

0.005

0.01

0.015

0.02

0.025

0.03Strom - Prozessor (U an 2.128 )

Zeit in s

Spa

nnun

g in

V

0.0µWs (0.0ms) 57.0µWs (3.0ms) Messung

39.1µWs (8.0ms) Reset/Init clock 97.1µWs (10.5ms) Initialisierung Chirp Sequencer

25.7µWs (2.8ms) Registerkonfiguration 15.4µWs (1.6ms) Kalibrierung Rx

9.5µWs (1.0ms) Kalibrierung Tx

12.1µWs (1.3ms) Kalibrierung Chirp DAC Filter 15.0µWs (1.7ms) Tx

0.0µWs (0.9ms) Rest

Energie: 271µWsLeistung: 8.8mW

Auto-Mode Default-Initialisierung

-0.005 0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.040

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

Strom - Funkmodul (U an 2.092 )

Zeit in s

Spa

nnun

g in

V

0.0µWs (0.0ms) 8.4µWs (3.0ms) Messung

68.5µWs (8.0ms) Reset/Init clock 624.1µWs (10.5ms) Initialisierung Chirp Sequencer

65.7µWs (2.8ms) Registerkonfiguration 88.2µWs (1.6ms) Kalibrierung Rx

55.2µWs (1.0ms) Kalibrierung Tx

125.5µWs (1.3ms) Kalibrierung Chirp DAC Filter 77.6µWs (1.7ms) Tx

16.9µWs (0.9ms) Rest

Energie: 1130µWsLeistung: 37mW


Fields of application

Family of inclination and acceleration sensors

Current applications :

Mobile machines (building-, agricultural and forestry machines) ‏

Lorries

Ship building

Solar plants

Condition Monitoring


Examples for application of energy-autonomous sensors

Tower crane (construction progress depended on length) ‏

Vibration diagnosis (CMS) ‏

Monitoring of hydraulic pumps

Moved systems (measuring value logging and transmission at motor spindle) ‏

Reducing of cables in length and angular measuring systems


Contact

GEMAC - Gesellschaft für Mikroelektronikanwendung Chemnitz mbH

Zwickauer Straße 22709116 ChemnitzGermany

Tel : +49 371-3377115Fax: +49 371-3377272

E-Mail: [email protected] Fair 2011 Hall 9 Booth H28

Documents

GEMAC - Gesellschaft für Mikroelektronikanwendung …Streaming of gaseous and liquid substances (i.e. industrial mill, flow meter) ... Working principle (conversion of physical values