How Inverters Have, Can, and Should Be Used for Ancillary Services

16 Pages·2017·1.01 MB·English

Connecting the Dots:
How inverters have, can, and should
be used for ancillary services
Donny Zimmanck
Principal Engineer
Enphase Energy
History of Inverter Participation
Sparse grid connected systems seen as negligible.
Interconnection rules designed to enforce non-
participation
.
UL 1741
P1547 Initiated
1999 2001 2003 2005 2011 2012 2014 2015 2016 2017
UL 1741 Revised
Synchronized with
IEEE 929 and 519
2
History of Inverter Participation
Rapidly falling costs acceleration adoption. Issues
begin to be observed on high penetration circuits.
IEEE 1547 Approved
UL 1741
Underlying jurisdiction
P1547 Initiated
for Interconnections
1999 2001 2003 2005 2011 2012 2014 2015 2016 2017
UL 1741 Revised
Synchronized with
IEEE 1547.1
IEEE 929 Published
Testing of
Interconnection
Systems
UL 1741 Revised
Harmonized with
3 1547.1
History of Inverter Participation
Industry responds by developing new interconnection
behaviors. The “smart inverter” is born.
IEEE 1547A (.1A)
IEEE 1547 Approved
Amendment to allow
UL 1741
Underlying jurisdiction
Rule 21 and Rule 14H
P1547 Initiated
for Interconnections
1999 2001 2003 2005 2011 2012 2014 2015 2016 2017
UL 1741
UL 1741 Revised
Supplement A
Synchronized with
IEEE 1547.1 Rule 21 Settlement Certification for
IEEE 929 Published Rule 21 and Rule
Testing of 14H
Interconnection
Systems
HECO implements
mandatory ride-
UL 1741 Revised
through
Harmonized with
4 1547.1
History of Inverter Participation
Communication and interoperability standards to
enable coordinated DER participation in grid regulation
and control.
IEEE P1547 Revision
Will supersede Rule 21
IEEE 1547A (.1A)
as the national
IEEE 1547 Approved
Amendment to allow
UL 1741 standard.
Underlying jurisdiction
Rule 21 and Rule 14H
P1547 Initiated
for Interconnections
1999 2001 2003 2005 2011 2012 2014 2015 2016 2017
UL 1741
UL 1741 Revised
Supplement A
Synchronized with
IEEE 1547.1 Rule 21 Settlement Certification for
IEEE 929 Published Rule 21 and Rule
Testing of 14H
Interconnection
Systems
HECO implements
mandatory ride-
UL 1741 Revised
through
Harmonized with
5 1547.1
Smart Inverter Functions
Good Citizen Behaviors Ancillary Functions
• Grid Entry Fee • Historically non-free service
• Outside ANSI limits • Within ANSI limits
• Functions • More dependence on communication
• voltage ride through • Functions
• frequency ride through • commanded var
• return-to-service ramp-rate • commanded power limiting
• freq-watt with ANSI dead-band • freq-watt within ANSI limits
• volt-var with ANSI dead-band • volt-var within ANSI limits
• volt-watt with ANSI dead-band • volt-watt within ANSI limits
Fixed power factor = grey area
Reduces inverter power rating
6
Hurdles to Adoption
Standardization
1.
Manufacturers can’t support everything and the kitchen sink
•
Certification
2.
Interoperability and performance verification
•
Communication (Security)
3.
New attack surfaces
•
Scalability
4.
Exponential node increase
•
Compensation
5.
How to implement appropriate incentives
•
7
Standardization
(currently) P1547 outlines 1 or 5 protocols be used
•
IEEE 2030.5 (SEP 2.0) – REST, HTTP, IEC 61968/61850, XML
1.
IEEE 1815 – DNP3
2.
Sunspec Modbus – IEC 61850, security?
3.
IEC 61850-8-1 over MMS
4.
IEC 61850-8-2 over XMPP
5.
Alternatives allowed under mutual agreement

Issues
•
No MQTT or CoAP - Emerging stars of the IoT space
1.
• Persistent, low latency, low bandwidth connections with millions of nodes
• Flexibility vs. interoperability tradeoff
• TLS not as well established as HTTP(S)
Plugging security holes in option 3 may create interoperability issues
2.
• Sunspec more suited to site-level communications
• 2030.5 designed to be run on-top of Sunspec
8
Idea: Cloud level compliance
MQTT
Web Apps
PLC IEEE 2030.5 Server
HTTP
DERP Aggregator
IEEE 2030.5 Client
SunSpec/
Modbus HTTP
RTU
IEEE 2030.5 Server
9
Certification and Compliance
UL1741 is just a product certification
•
Product safety
•
Compliance with IEEE1547 allows grid connection
•
How are systems approved for ancillary
•
services?
2030.5 (SEP 2.0) cert program for interoperability
•
P1547 does add interoperability (will be tested by 1741)
•
System level certification testing
•
Performance verification tests?
•
Self testing
•
10