View
9
Download
0
Category
Preview:
Citation preview
National Smart Metering ProgramNational Smart Metering Program
NSMP Business Requirements Work Stream
Interval Energy Data Channels
Version number: Version 1.0
Status: Final
Author: Dr Martin Gill
Date published: 6th February 2011
File name: NSMP Interval Energy Data Channels v1.0.doc
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 2 of 14
Security Classification: Unrestricted
Table of Contents
1 DOCUMENT CONTROL ........................................................................................................................... 3
1.1 VERSION CONTROL ............................................................................................................................... 3 1.2 APPROVAL ............................................................................................................................................. 3 1.3 REFERENCES ......................................................................................................................................... 3 1.4 DISCLAIMER ........................................................................................................................................... 3
2 INTRODUCTION ......................................................................................................................................... 4
2.1 BACKGROUND ........................................................................................................................................ 4
3 DEFINITIONS TO BE USED FOR ENERGY FLOWS .......................................................................... 4
3.1 ACTIVE ENERGY .................................................................................................................................... 4 3.2 REACTIVE ENERGY ................................................................................................................................ 5 3.3 FOUR QUADRANT METERING ................................................................................................................ 5
4 ENERGY MEASUREMENTS FOR EACH METER CONFIGURATION ............................................ 7
4.1 GLOSSARY DEFINITIONS ....................................................................................................................... 7 4.1.1 Accumulated Energy .................................................................................................................. 7 4.1.2 Interval Energy ............................................................................................................................ 8
4.2 ENERGY QUANTITIES ............................................................................................................................. 9 4.2.1 Single Phase Single Element Meters ...................................................................................... 9 4.2.2 Three Phase Meters ................................................................................................................ 10 4.2.3 Single Phase Two Element Meters ....................................................................................... 11
APPENDIX A – GLOSSARY ............................................................................................................................ 13
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 3 of 14
Security Classification: Unrestricted
1 Document Control
1.1 Version Control
Version Date Description Amended by
0.1 6/11/2009 First Draft Dr Martin Gill
0.2 5/1/2010 Included reference to AS62053.23, added disclaimer and updated figures to use varh
Dr Martin Gill
0.3 31/3/2010 Included discussion of the recorded measurements
Dr Martin Gill
0.4 12/4/2010 Update to include the new definitions agreed by the BRWG
Dr Martin Gill
1.0 6/2/2011 Release as Final Dr Martin Gill
1.2 Approval
Authorised by Signature Date
NSSC Program Director
18/2/11
1.3 References
The following documents are referred to in this document.
Document Name Version
Electricity metering equipment (ac) — Particular requirements Part 23: Static meters for reactive energy (classes 2 and 3)
AS 62053.23—2006
Handbook for Electricity Metering Edison Electric Institute
10th Edition
National Metering Identifier Procedure (NMI) Version No: 5 16 July 2006
NMSP Function 11 Import/Export Version 1.0
NSMP Power Factor Measurement Version 1.0
NSMP Smart Metering Infrastructure Functionality Specification Version 1.1
1.4 Disclaimer
This discussion paper was produced by Dr Martin Gill of KEMA Consulting in order to assist the Business Requirements Working Group (BRWG) in the development of the Smart Metering Infrastructure Minimum Functionality Specification. This paper has not been vetted or endorsed by the BRWG or the National Stakeholder Steering Committee (NSSC).
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 4 of 14
Security Classification: Unrestricted
2 Introduction
2.1 Background
The National Smart Metering Infrastructure Functionality Specification (SMI F.S.) supports the measurement and recording of both active and reactive energy. This document details the conventions that will be used for active and reactive energy measurement.
The smart meter is also able to store the active and reactive energy in trading intervals. This document details the accumulated energy values recorded by each meter configuration and available for storage in interval energy channels.
3 Definitions to be Used for Energy Flows
3.1 Active Energy
The SMI F.S requires that all meter are capable of measuring and recording bi-directional energy flows1. The smart meter must be capable of separately recording active energy export and active energy import. The National Electricity Market (NEM) clearly defines the direction of active energy flow, which is viewed from the perspective of the electricity network. As such active energy export is energy supplied to the customer and active energy import corresponds to energy supplied from the customer to the grid (for example from on-site generation).
Figure 1: Direction for Import and Export within the NEM By convention active energy flows are considered to align with the X-axis of a graph. The following figure depicts the two separate active energy values recorded by the smart meter:
Figure 2: Active Energy Flows
1 In the original list of Ministerial Council on Energy (MCE) recommended functions this was Function 11 Import/Export
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 5 of 14
Security Classification: Unrestricted
3.2 Reactive Energy
The SMI F.S requires the smart meter to be able to measure bi-directional reactive energy flow2. Conventions for the direction of reactive energy flow are not as clearly defined as those for active energy flow. It is proposed that the SMI F.S. follow the conventions outlined in Australian Standard AS:62053.23—2006, with the exception that the perspective is changed to align with the NEM pool rather than the meter.
The following figure depicts the two separate reactive energy values recorded by the smart meter. These are drawn on the same axes as depicted in Figure 2 highlighting that reactive energy measurements align with the Y-axis. The difference will be explained in greater detail in Section 3.33.
Figure 3: Reactive Energy Flows
3.3 Four Quadrant Metering
As outlined above the smart meter is required to separately record active energy import, active energy export, reactive energy import and reactive energy export. Measurement of these four values is often referred to as four quadrant metering.
The NEM defines all energy flows relative to the “pool”. Energy export therefore describes flow out of the pool, while energy import describes flow into the pool. This applies to both active energy (kWh) and reactive energy (kvarh).
Following the convention detailed in AS: 62053.23—20064 and in the 10th edition of the handbook for Electricity Metering from Edison Electric Institute we define the quadrants as shown in Figure 4 and Table 1.
2 In the original list of MCE recommended functions this was Function 10 Power Factor 3 For even greater detail the reader is referred to the NSMP Power Factor discussion paper. 4 Noting that in AS:62053.23 Imported and Exported are taken from the perspective of the customer premise while the NSMP uses the NEM perspective of energy flow to and from the Pool.
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 6 of 14
Security Classification: Unrestricted
Figure 4: Four Quadrant Metering The direction of energy flow for active and reactive power corresponding to each quadrant is shown in Table 1.
Table 1: Definitions Used for Four Quadrant Metering
Quadrant Watts vars
1 Exported Exported
2 Imported Exported
3 Imported Imported
4 Exported Imported
The voltage and current waveforms corresponding to each axis shown in Figure 4 are shown in Figure 5. These axis points depict ‘purely’ active energy flow and ‘purely’ reactive energy flows:
Figure 5: Voltage and Current Waveforms Corresponding to Each Axis
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 7 of 14
Security Classification: Unrestricted
The voltage and current waveforms corresponding to each quadrant are shown in Figure 6 below.
Figure 6: Voltage and Current Waveforms Corresponding to Each Quadrant
4 Energy Measurements for Each Meter Configuration
4.1 Glossary Definitions
Terms in common usage within the metering community do not align with the terms used in chapter 10 of the National Electricity Rules. This section attempts to arrive at a common definition for each of the ‘data types’ that can be read from smart meters.
4.1.1 Accumulated Energy
The SMI F.S. provides the glossary definition of accumulated energy value as
Accumulated energy value means the value resulting from the measurement representing a flow of energy at a metering point.
If we consider a simple spinning disk electricity meter then a single value is displayed on the meter, this accumulated energy value represents a particular quantity (depending on how the meter is installed):
Figure 7: Accumulated Energy Value A smart meter will have several different measurement quantities for which it records separate accumulated energy values. This leads to the glossary definition of accumulated energy data.
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 8 of 14
Security Classification: Unrestricted
Accumulated energy data means one or more accumulated energy values.
Reading the Accumulated energy data is described in the following figure:
Figure 8: Accumulated Energy Data
4.1.2 Interval Energy
With the addition of a meter clock it is possible to make measurements at specific times (or over specific time periods). This results in the measurement of energy flows in trading intervals. Identification of each of these data streams requires clarification.
Interval energy value means the value resulting from the measurement representing a flow of energy at a metering point over a trading interval.
Figure 9: Interval Energy Value When a series of consecutive Interval energy values are collected this is results in an Interval energy channel. The glossary definition is given as:
Interval energy channel means a series of interval energy values measured and stored over consecutive trading intervals.
Figure 10: Interval Energy Channel
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 9 of 14
Security Classification: Unrestricted
When a number of interval energy channels are read we refer to this as interval energy data:
Interval energy data means the interval energy channels stored by a meter.
Figure 11: Interval Energy Data
4.2 Energy Quantities
A smart meter complying with the SMI F.S. will be capable of measuring active and reactive energy flow in a power conductor. The SMI F.S. has chosen to separately record imported and exported energy flows, so the measurement of an energy flow into the premises (exported from the pool) will be recorded separately from energy flow from the premises (Imported to the pool).
There is a fundamental limitation on a single measurement element, it can only measure the difference between the energy flows in the power conductor. So while we record two separate values they actually refer to the same measurement. It is only when that single value is positive we have chosen to record the value as an “exported” accumulated energy value and when negative as an “imported” accumulated energy value.
Metering configurations may contain different numbers of measurement elements which may result in different energy quantities. This is discussed in the following sections.
4.2.1 Single Phase Single Element Meters
Single phase single element meters have a single measurement element. They are only capable of measuring the total energy flow at the connection point. The measurement of active and reactive energy flow results in the record of four accumulated energy values. Corresponding to total imported active energy, total exported active energy, total imported reactive energy and total exported reactive energy. The four recorded accumulated energy values can be selected for storage in Interval energy channels.
This metering configuration and the supported accumulated energy values are shown in Figure 12.
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 10 of 14
Security Classification: Unrestricted
Figure 12: Energy Data Values Supported by Single Phase Single Element Meters
4.2.2 Three Phase Meters
Three phase meters typically employ three measurement elements5 to measure energy flows through a metering point. The total active and reactive energy is calculated as the sum of the energy flow measured on each measurement element. The calculation results in the active and reactive energy flows through the metering point. As for the single phase single element meter this results in four separately recorded accumulated energy values, referred to as total imported active energy, total exported active energy, total imported reactive energy and total exported reactive energy. The four accumulated energy values can be selected for storage in interval energy channels. This metering configuration and the supported accumulated energy values are shown in
Figure 13.
Figure 13: Energy Data Values Supported by Three Phase Meters
The accumulated energy values recorded each of which can be selected for storage in trading intervals for the meter configurations single phase single element and three phase are detailed in Table 2:
Table 2: Accumulated Energy Values Recorded by Single Phase Single Element and Three Phase Meters
5 Three phase four wire meters will employ three measurement elements while three phase three wire meters can employ two measurement elements. The summation of all measurement elements applies regardless of the actual number of measurement elements.
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 11 of 14
Security Classification: Unrestricted
Accumulated Energy Values recorded by the meter
Total Imported Active Energy (kWh)
Total Exported Active Energy (kWh)
Total Imported Reactive Energy (kvarh)
Total Export Reactive Energy (kvarh)
4.2.3 Single Phase Two Element Meters
The SMI F.S. describes a single phase two element meter. It was initially assumed that the two element meter could be used in place of two single phase meters, however this would result in eight accumulated energy values corresponding to the values listed in Table 2 for both element 1 and element 2. There are two issues with this assumption. Firstly it would not support the measurement of net energy flows at the metering point and secondly this would provide too many channels of reactive energy data. These will now be discussed:
The discussion paper NSMP Function 11 Import/Export highlights that legislated feed-in tariffs require the meter to measure the instantaneous net flow through the metering point. The total active energy through the metering point is calculated as the sum of the energy flow measured on each measurement element. This is exactly the same requirement as depicted for three phase meters (described in section 4.2.2) where the meter calculates the flow across the measurement elements. For active energy this results in six different active energy values, total imported, total exported, element 1 imported, element 1 exported, element 2 imported and element 2 exported.
Reactive energy measurement was added to the SMI F.S. for audit purposes, as such the values are only required per connection point (not per measurement element). In a similar manner to the calculation of total active energy, the reactive energy flows across the measurement elements are summed resulting in only two reactive energy values, total imported reactive energy and total exported reactive energy.
The resulting eight accumulated energy values are shown in Figure 14.
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 12 of 14
Security Classification: Unrestricted
Figure 14: Single Phase Two Element Meters For two element meters the accumulated energy values recorded by the meter and the corresponding interval energy channels that can be selected for storage in trading intervals are detailed in Table 3.
Table 3: Accumulated Energy Values Recorded by Single Phase Two Element Meters
Accumulated Energy Values recorded by the meter
Total Imported Active Energy (kWh)
Total Exported Active Energy (kWh)
Total Imported Reactive Energy (kvarh)
Total Exported Reactive Energy (kvarh)
Element 1 Imported Active Energy (kWh)
Element 1 Exported Active Energy (kWh)
Element 2 Imported Active Energy (kWh)
Element 2 Exported Active Energy (kWh)
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 13 of 14
Security Classification: Unrestricted
Appendix A – Glossary
The following acronyms are in the NSMP Glossary.
ACOSS Australian Council of Social Services
AEMC Australian Energy Market Commission
AEMO Australian Energy Market Operator
AER Australian Energy Regulator
AMI Advanced Metering Infrastructure (Victorian smart metering program)
AS Australian Standard
B2B Business to Business
BPRG B2B Procedures Reference Group (established under the IEC)
BPPWG Business Processes and Procedures Working Group (established under the NSSC)
BRDRG Business Requirements Definition Reference Group (established under the AMI program)
BRWG Business Requirements Working Group (established under the NSSC)
CATS Consumer Administration and Transfer Solution
COAG Council of Australian Governments
DNSP Distribution Network Service Provider
DRET Commonwealth Department of Resources, Energy and Tourism (also referred to as RET)
EEEC Equipment Energy Efficiency (E3) Committee
ENA Energy Networks Association
ERAA Energy Retailers Association of Australia
ESC Essential Services Commission
FRC Full Retail Contestability
FRMP Financially Responsible Market Participant
HAN Home Area Network
IEC Information Exchange Committee (established under section 7.2A.2 of the Rules)
IHD In-home Display
LNSP Local Network Service Provider
MCE Ministerial Council on Energy (established under the COAG)
MDA Metering Data Agent
MDF Metering Data File
MDFF Metering Data File Format
MOU Memorandum of Understanding
MRG Metrology Reference Group (established under the RMEC)
MSATS Market Settlement and Transfer Solution
MTWG Metering Technology Working Group (established under the AMI program)
NCRE National Consumer Roundtable on Energy
NSMP Business Requirements Work Stream Interval Energy Data Channels
File Name: NSMP Interval Energy Data Channels v1.0.doc Page 14 of 14
Security Classification: Unrestricted
NECF National Energy Consumer Framework
NEL National Electricity Law
NEM National Electricity Market which excludes Western Australia and Northern Territory
NEMMCO National Electricity Market Management Company
NEO National Electricity Objective (as set out in section 7 of the NEL)
NER National Electricity Rules
NSMP National Smart Metering Program
NSSC National Stakeholder Steering Committee (National Smart Metering Program)
NT Northern Territory
OMRV Operating Model Requirements Version (Victorian AMI Program)
PDRG Business Process & Data Reference Group (established under the RMEC)
PwC PricewaterhouseCoopers
PTWG Pilots and Trials Working Group (established under the NSSC)
RET Commonwealth Department of Resources, Energy and Tourism
RIS Regulatory Impact Statement
RFP Request for Proposal
RMEC Retail Market Executive Committee (an advisory committee to AEMO)
RP Responsible Person
RPWG Retail Policy Working Group (established under the MCE)
RWG Regulation Working Group (established under the NSSC)
SCO Standing Council of Officials (as established under the MCE)
SM Smart Metering
SMCN Smart Metering Communication Network
SME Subject Matter Expert
SMI Smart Metering Infrastructure
SMMS Smart Metering Management System
SMWG Smart Metering Working Group (established under the SCO)
SWIS South Western Interconnected System in Western Australia
TFWG Testing Framework Working Group
TOR Terms of Reference
TRWG Technical and Regulatory Working Group (established under the AMI Program)
WA Western Australia
WAIMO Western Australian Independent Market Operator
WEM Wholesale Electricity Market (Western Australia)
WIGS Wholesale Inter-connector Generator and Sample
WG Working Group
Recommended