Western Wind and Solar Integration Study Phase 3 – Frequency Response and Transient Stability

Abstract

NREL prints on paper that contains recycled content. iii 2 Develop Study Databases and Establish Initial Conditions This section contains definitions and context for the study. Specifically, Section 2.1 discusses the selection and improvement of the study cases. Refinement and documentation of the study cases are reported in Section 2.2. Performance and monitoring metrics are described in Section 2.3. The development of the Hi-Mix (33% annual energy penetration from wind and solar) cases is reported in Section 2.4 through Section 2.6. 2.1 Selection of Study Cases This section covers the selection of the WECC cases from which the WWSIS-3 study cases were developed. The investigation and improvement of the selected cases are discussed in detail. The initial condition metrics for new base cases are presented. 2.1.1 Key Considerations The study databases were selected based on the following requirements: • The study case should be credible and meaningful. • The study case should have a longer horizon, e.g., extend beyond the year 2020. • The load flow in the study cases should include major system generation changesadditions and retirements-for which there is some degree of consensus in WECC. • The study case should have a transmission build-out that is realistic and not overly optimistic.

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