SunSpec String Combiner Models

Transcription

1 Document #: Document Status: DRAFT Version 1.4 SunSpec String Combiner Models SunSpec Alliance Interoperability Specification Contributors: John Blair, John Nunneley, Steve Lewis, Rafal Pabich, Alessio Costantini, Aaron McNally, Aaron Parker, Lynn Linse, Lior Handelsman, Yaron Binder, Ronnie Petterson, Bob Schmitt, Matthew Perry, Bryan Thomas, Peter Rexelius, Steve Drouilhet, Martin Beran, Bob Fox, Cliff Baumann ABSTRACT The SunSpec Alliance Interoperability Specification suite consists of the following documents: SunSpec Technology Overview SunSpec Information Model Specification SunSpec Information Model Reference Spreadsheet Collection of SunSpec Device Category Model Specifications SunSpec Plant Extract Document This document is a member of the collection of Device Category Model Specifications; it covers string combiner models. String Combiner Models Specification 1

2 License Agreement and Copyright Notice Copyright SunSpec Alliance All Rights Reserved. Modbus is a copyright of Modbus.org. All other copyrights and trademarks are the property of their respective owners. This document and the information contained herein is provided on an "AS IS" basis and the SunSpec Alliance DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY OWNERSHIP RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. This document may be used, copied, and furnished to others, without restrictions of any kind, provided that this document itself may not be modified in anyway, except as needed by the SunSpec Technical Committee and as governed by the SunSpec IPR Policy. The complete policy of the SunSpec Alliance can be found at Prepared by the SunSpec Alliance 4030 Moorpark Avenue, Suite 109 Website: info@sunspec.org San Jose, CA Change History Revision Date Reason JKN: Reflect 401,402 models superseded by 403, Change to new SunSpec document format Updated descriptions. Underlying model definitions are unchanged. String Combiner Models Specification 2

3 Contents Introduction... 4 String Combiner Data Points... 4 String Combiner Data Models and Modbus Maps... 4 Combiner and Input String Event Flags... 4 Basic String Combiner Modbus Mapping (403)... 4 Advanced String Combiner Modbus Mapping (404)... 4 About the SunSpec Alliance... 5 String Combiner Models Specification 3

4 Introduction This SunSpec Alliance Interoperability Specification describes the data models and Modbus register mappings for string combiner devices used in Photovoltaic systems. The specification describes a basic device map and an advanced device map. Both maps may contain any number of combiner inputs and are therefore variable in length. Combiner units that support environmental measurements should include an appropriate model from the SunSpec Environmental Models specification. The full set of specifications is available for download at We strongly suggest that you download the latest versions, and note the status of the models you wish to implement, before beginning your implementation. String Combiner Data Points The following types of data points are provided to describe string combiners: String Combiner DC values String Combiner Event Flags String Combiner String Input Values String Combiner Data Models and Modbus Maps Combiner and Input String Event Flags String combiner models have numerous event flags. Any number of events may be active at the same time, and as a result the data elements containing flags are implemented as bit- maps. The Evt field applies to the Combiner as a whole while the InEvt field applies to the specific string input. Events at the InEvt level are logically OR d to produce the corresponding Evt value. Users can trigger on the combiner level event and then drill down to the string level to determine which string(s) are at fault. Fields with bitmaps are also available for vendor- specific additions to combiner or string level event flags. Basic String Combiner Modbus Mapping (403) The Basic String Combiner Modbus Mapping is a variable length model. The model supports combiners of any number of inputs. Combiner level readings provide combined values for Current, AmpHours, Voltage, Status, and Events. Individual string readings are provided for the Current and Events. Advanced String Combiner Modbus Mapping (404) String Combiner Models Specification 4

5 The Advanced String Combiner Modbus Mapping is a variable length model. The model supports combiners of any number of inputs. Advanced measurements and metered values for Voltage, Power, Energy, and Performance Ratio are provided at the Combiner and Input String level. Performance Ratio is defined to be the Actual Performance / Expected Performance. Actual Performance is measured and metered by the device. The Expected Performance is calculated based on a variety of factors. The method of calculation for the Expected and Actual Performance is not part of this specification and is vendor specific. About the SunSpec Alliance The SunSpec Alliance is a trade alliance of developers, manufacturers, and service providers, together pursuing information standards for the distributed energy industry. SunSpec standards address most operational aspects of PV and other distributed energy power plants on the smart grid including residential, commercial, and utilityscale systems thus reducing cost, promoting innovation, and accelerating industry growth. Over 60 organizations are members of the SunSpec Alliance, including global leaders from Asia, Europe, and North America. Membership is open to corporations, nonprofits, and individuals. For more information about the SunSpec Alliance, or to download SunSpec specifications at no charge, please visit String Combiner Models Specification 5