*4.1. Input-Output Channels of Real-Time Digital Simulator*

The Opal-RT RTDS is equipped with analog and digital input-output modules. The voltage range for analog signals is ±15 V whereas the voltage levels for digital signals is 0 and +15 V.

#### *4.2. Input-Output Channels of Controller Card*

The controller used in this work is a TMS320F2812 DSP processor-based controller card. The voltage range for analog signals is ±10 V whereas the voltage levels for digital signals is 0 and +15 V.

#### *4.3. User Interface Panel Signals*

The input to the simulated PV array is solar irradiance, which can be provided to the simulated plant through the analog input channel of RTDS from a POT mounted on a user interface panel. The minimum value of the POT output refers to an irradiance of 0 and the maximum value of the POT refers to 1000 W/m2. From the user interface panel, start/stop commands, and emergency stop commands are given to the controller card for the plant operations. The controller card receives temperature signals of from the isolation transformers and power stacks from the user interface panel. The possible fault signals are also sent to the controller card hence different faults can be simulated to check the functionality of the controller and control algorithm.
