Trimark Associates Inc. has commissioned a unified control and data telemetry system to manage 23 SMA Sunny Central 800CP-US photovoltaic inverters at SunEdison's 24 MW Cascade solar project in California.
The 150-acre PV power plant incorporates over 75,000 SunEdison Silvantis monocrystalline modules mounted on SunEdison AP90 single-axis trackers. Cascade is supplying electricity to San Diego Gas & Electric through a 20-year power purchase agreement.
Trimark says the T1-S data acquisition and control system provides a unified user interface and allows site operators to send commands to connect or disconnect inverters, adjust maximum power generation levels and establish power factor set points. Operators can control all inverters as a single resource or each inverter separately.
The system provides real-time operational data to the California Independent System Operator (CAISO), performance monitoring and data visualization, device status and alarms, and historical trending and reporting. In related work, Trimark also integrated CAISO revenue metering and meteorological instrumentation for Cascade.
Trimark says regulatory and business drivers are causing a shift in system requirements surrounding control of utility-scale PV generation, as utilities and grid operators begin to address higher penetrations of distributed energy resources on the grid. Inverter control requirements have been driven by regulations and standards such as pending IEEE 1547 A, pending California Public Utility Commission Rule 21 updates, UL 1741 and IEC 61850.
‘These changes are causing the industry to shift from systems that provide exclusively autonomous control to systems that provide a combination of autonomous dynamic and interactive immediate controls capabilities,’ says Robert Wood, Trimark's chief technology officer.
In addition, Wood says, many resource owners are requesting more data and control of their sites for use in performance improvement and asset management.