WECC REMTF Workshop Spencer Tacke Spencert@mid.org WECC Renewable Energy System Models Workshop March 9, 2016

REMTF Workshop Accurate, validated models are required for reliable and economic power system operations NERC Reliability Standards require that power flow and dynamics models be provided

REMTF Workshop Under WECC modeling guidelines (i.e., Generating Unit Model Validation Policy), all wind and PV power plants with aggregated capacity 20 MVA or larger must be modeled explicitly in WECC power flow and dynamics base cases, using models in the WCC Approved Dynamic Model Library Manufacturer-specific dynamic models commonly provided for interconnection studies are not adequate for regional planning. WECC requires the use of approved models.

Recent Data Gathered by PPMVDTF WECC base cases have close to 29 GW of total wind generation 74 plants with 5 GW of generating capacity are connected at 24 to 35-V level, and therefore have no collector system representation 94 plants with 5.2 GW of generating capacity have no dynamic models 54 plants with 2.8 GW of generating capacity are modeled with inappropriate dynamic models

REMTF Workshop There is a significant opportunity for model improvement The REMTF (under the MVWG) has led a multi-year effort developing dynamic models for wind and PV generators The effort has been a broad industry effort The collaborative community has worked under the auspices of the WECC and the REMTF, and the developed models have been WECC approved and are in major commercial software platforms

Wind Generation Dynamic Models Development was done in phases Initial implementation of type 3 and 4 types represented a limited set of manufacturers Recently developed second generation models have the capabilities to capture a wider group of wind generation turbine makes and models

Grid-Connected PV Systems Most are residential and commercial scale connected to distribution networks But many are large generation facilities connected to the transmission system

Second Generation Models They were developed deliberately in a modular format to facilitate the ability to add new features and functions to the library of models without significant effort 1st generation models were developed without the flexibility to represent various vendor equipment 2nd generation models were developed with more flexibility and were validated against several vendor data

Goals of Second Generation Generic Models Allow for easy implementation of new modules to build on existing components and allow for the ever-growing and changing technology, and Allow for emulation of a wider range of control philosophies and thus the ability to be parameterized for representing a wide range of equipment

Wind Turbine Diagrams

The 2nd Generation Renewable Energy System (RES) Models Function 1st or 2nd Generation regc_a RES Generator/Converter Model 2nd reec_a RES Electrical Controls Model A reec_b RES Electrical Controls Model B reec_c RES Electrical Controls Model C repc_a RES Plant Controls Model A repc_b RES Plant Controls Model B 2nd (not yet finalized) wtgt_a WTG Turbine Shaft Model A wtgar_a WTC Aero-dynamic Model A wtgpt_a WTG Pitch Controller Model A wtgtrq_a WTG Torque Controller Model A wt1p_b Pitch Controller for type 1 WTG Model B wt1g Type 1 WTG generator model 1st wt1t Type 1 WTG turbine shaft model wt2g Type 2 WTG generator model wt2e Type 2 WTG variable external rotor resistance controller wt2t Type 2 WTG turbine shaft model lhvrt low/high voltage ride-through relay model lhfrt low/high frequency ride-through relay model

The 2nd Generation RES Models Model Combination Type 1 WTG wt1g, wt1t, wt1p_b Type 2 WTG wt2g, wt2e, wt2t, wt1p_b Type 3 WTG regc_a, reec_a, repc_a, wtgt_a, wtgar_a, wtgpt_a, wtgtrq_a Type 4 WTG regc_a, reec_a, repc_a (optional: wtgt_a) PV plant regc_a, reec_b (or reec_a), repc_a BESS regc_a, reec_c (optional: repc_a)

The 2nd Generation RES Models

The 2nd Generation RES Model: WTG Type 1 and Type 2

The 2nd Generation RES Model: WTG Type 3

The 2nd Generation RES Model: WTG Type 4

The 2nd Generation RES Model: PV

References WECC 2nd Generation WTG Model Specifications: https://www.wecc.biz/Reliability/WECC-Second-Generation-Wind-Turbine-Models-012314.pdf WECC PV Model Specifications: https://www.wecc.biz/Reliability/WECC-Solar-PV-Dynamic-Model-Specification-September-2012.pdf WECC PV Modeling Guide: https://www.wecc.biz/Reliability/WECC%20Solar%20Plant%20Dynamic%20Modeling%20Guidelines.pdf WECC WTG Modeling Guide: https://www.wecc.biz/Reliability/WECC%20Wind%20Plant%20Dynamic%20Modeling%20Guidelines.pdf Model User Guide for Generic Renewable Energy System Models: http://www.epri.com/abstracts/Pages/ProductAbstract.aspx?ProductId=000000003002006525