The new Elgar TerraSAS Solar Array Simulators from Ametek simulate photovoltaic (PV) dynamic solar irradiance and temperature characteristics over a range of weather conditions from clear to cloudy and over a specified time interval to produce the current / voltage (IV) characteristics for the specified PV array for those conditions. They are available from Westek Electronics .
For ease of use, the system's simulation engine is able to download data from the National Renewable Energy Laboratory (NREL) Solar Advisor Model database defining key parameters - open circuit voltage (Voc), short circuit current (Isc) and maximum power point voltage (Vmpp) at 25 degrees C and 1000 W/m2 irradiance - so that the IV curve can be calculated according to a standard solar cell model for virtually any fill factor or solar material. Other PV panel IV curves can be entered manually.
Systems with multiple panels with different characteristics resulting in "multiple hump" IV curves also can be simulated. In addition, the TerraSAS Solar Array Simulators are capable of simultaneously simulating up to 24 parallel channels for use with micro-inverters.
An essential part of this testing is to provide the inverter under test with accurate simulation of the PV array response to its maximum power point tracking (MPP) function. To perform this task, the power source must accurately process the PV array's IV curve without filtering the low frequency ripple voltage produced by the inverter to track MPP.
The modular, rack-mounted Elgar TerraSAS Solar Array Simulators offer single or multiple programmable DC power supplies in 1 to 15 kW increnets, a controller module and simulation engine for sequencing IV curves, keyboard and GUI, as well as relay assembly for output isolation and polarity reversal.