Wireless Data Communication in

Substations

Mladen Kezunovic (P.I.)

Costas N. Georghiades

Alireza Shapoury

PSERC

PSerc Review Meeting

Texas A&M University

College Station

College Station, March 22, 2002

2

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

OUTLINE

Part I Summary Report

Part II Technical Report

Conclusions

3

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

OUTLINE OF PART I

Introduction Project Background and Brief History Recent Activities Statement of Work Activity Schedule Project Status

4

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Introduction

• Defining the Most Appropriate Wireless Strategy for Substation Environment

• A Continuation of the Previous Reports Presented Earlier to the PSERC Industry Advisors

• Covering Activities in the period December 2001- March 2002

5

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

• ISM (Industrial,Scientific and Medical) band

• Wide Usage

• License-free

• Higher RF Power If Spread Spectrum

• Substation Monitoring Applications

• Cost-effective Communication

• Point of Concern:Specific Environment of Substation

Project Background and Brief History

6

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

•     Theoretical analysis and technical observations

• Core Spread Spectrum TechniquesFHSSDSSS

  •     Field measurement

• FreeWave Modems

• Diagnostic Software (Setup Plan)

  •    Identifying system characteristics

Recent Activities

7

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

TASK 1. Feasibility study and planning

TASK 2. Theoretical analysis and technical observations

TASK 3. Field measurement

TASK 4. Identifying characteristics of a reliable system

TASK 5. Special concerns

TASK 6. Finalizing the results, Documentation 

Statement Of Work

8

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Activity Schedule

9

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

• Identification of the Necessary Devices for Measurement (Accomplished)

• Measurement Setup Plan (Accomplished)  

• Theoretical Development (In Progress)

• Field Measurement (In Progress)

• The Project Follows the Specified Task Schedule

Project Status

10

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

OUTLINE OF PART II

Introduction

Theoretical Analysis and Technical Observations

Field Measurement

Identifying Characteristics of a Reliable System

Conclusion

11

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

• Use real-time and off-line data for better circuit breaker maintenance management

• Utilize new technologies of wireless communications and mobile agents

• As an example, improve efficiency of circuit breaker maintenance assessment

• Demonstrate the benefits of new communication and software technologies using utility maintenance management scenarios

Introduction

12

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

• Impulsive noises and EMI Impact On Wireless Channel

• Noise Sources In Substations

• Review of The Noise Impact On Spread Spectrum Schemes

• Crude Comparison Of DSSS And FHSS

• Worst-case Analysis

• Worst-case happens under different noise profiles for DSSS and FHSS

Theoretical Analysis and Technical Observations

13

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

• DSSS indicates approximately 5dB superior to that of FHSS under worst-case noise profile of their own

• Assessment of the likelihood of the Worst-case situations necessitates measurement

14

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Devices, Configuration and Operation Modes Measuring Statistics

• Average Noise Power • Average Signal Power• Average Packet Error • Temperature

Investigating Practical Issues (E.g. Antenna Type and Location, Proper Output Power)

Field Measurement

15

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Measurement Setup

16

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Revised Measurement Setup

17

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Achievable Baud Rate For Wireless Channel Maximum BER For Data Devices Necessary Response Time For The Wireless

Device Antenna Power Supply And Isolation Adequate Data Security

Identifying Characteristics of a Reliable System

18

PSERC

PSerc Review Meeting March 22, 2002Texas A&M University at College Station

Identification of noise sources in substation Worst-case analysis for two core SS modulation

formats Extraction of the necessary parameters (to be

measured) Measurement setup (modifications, verifications and

programming ) Measurement runs (In process) General requirements for the wireless system

candidates (Ongoing)

Conclusion