Passive components in PLECS are idealized and do not include physical parameters such as the associated resistance. You can simply place a resistor in series with a capacitor to add this effect, however. Attached is a PLECS Standalone model that contains a custom subsystem where a capacitor includes an equivalent series resistance (ESR) under the hood and is accessible as a mask parameter. It is simply provided for users who do not want to add a resistor in series connection each time in the schematic, but do require that a capacitor has an ESR associated with it.
cap_w_esr.plecs (5.79 KB)