Monitoring system for photovoltaic system
ABB’s PVI-PMU enables customers to control active and reactive power of the inverters in accordance with eeG-2009§6 and BDEW norms.
Thanks to its two RS485 ports, the PVI-PMU can be used for controlling the power generated by ABB Inverters in PV plants where an external data acquisition system has been installed too.
The proprietary Aurora Protocol is the communication protocol the PVI-PMU uses to exchange data with all ABB Inverters; meanwhile, the power control management commands, sent by an external source, are received through a dedicated analog and digital inputs.
The PMU provides three different control functions for the implementation of active power limitation and three different operating modes for reactive power control.
This combination of the “digital” input status and the signals received from the analog inputs enables one of the three active power control functions.
1. Active power limitation in four steps
2. Active power limitation in 11 steps
3. Continuous active power limitation
Reactive power is controlled using the 4-20 mA analog inputs.
Using the combination of analog and digital inputs, three different reactive power management operating modes are selectable:
1. Fixed cos(ϕ) based on the inverters nominal power
2. Fixed cos(ϕ) based on inverter instantaneous power
3. Fixed tan(ϕ) based on inverter instantaneous power