SMA POWER PLANT CONTROLLER - Manual (Page 33)

SMA Solar Technology AG 7 Operation
Operating Manual PPC-BE-P7-en-13 33
7.6.5 Adjusting the Configuration of the Power Plant Controller Slaves
Using Power Plant Controllers, you can monitor a PV power plant with up to 1,000 central inverters. The master/slave
concept of the Power Plant Controllers enables all 1,000 inverters to be controlled uniformly and simultaneously.
The Power Plant Controller master transmits the output values for the active and reactive power control to the
Power Plant Controller slaves and to all inverters connected to the master. A Power Plant Controller master can control
up to ten Power Plant Controller slaves.
In the Power Plant Controller master, the IP addresses of the Power Plant Controller slaves and the mode of the slave
operation must be set. If necessary, the Power Plant Controller slaves can be divided into different control groups. It can
also be set whether the Power Plant Controller master must pass the disconnect command to the slave or not. The settings
for the fast stop command can only be made using the user level "service technician".
Procedure:
1. Log into the user interface of the master as an installer (see Section 11.3.1, page 54).
2. Go to PPC > Grid system services > Device table PPC slave.
3. Enter the number of slaves for this Power Plant Controller master in the Number PPC slave field.
4. Enter the name of the slave in the Device name field.
5. Enter the IP address of the slave in the fields IP1 to IP4.
6. Adjust the setting for the mode of the slave operation in the Slave mode field:
7. If necessary, enter the number of the group that the slave belongs to in the Control group field.
7.7 Adjusting the Settings of the Modbus Server
The communication between the Power Plant Controller and the grid operator or a higher-level SCADA system takes
place via Modbus protocol. You can disable communication with the grid operator via Modbus protocol and change
the IP address of the Modbus server. You can configure whether setpoint changes are only to be accepted if the change
counter register is set simultaneously in the Modbus protocol.
If the Modbus Client is inactive, the connection will automatically be cut off after 60 seconds, even if the setting Setpoint
monitoring is activated. The time can be adjusted from 1 s to 60 s in the field Setpoint monitoring time.
Mode of slave
operation
Description
1 The active power setpoints are processed by the controller of the master and transmitted as
output values to the slave. The slave does not control but transmits the output values to the
inverters.
or
Cascade control: The active power output values of the master are processed by the slave
controller as setpoints and sent to the inverters. For this mode of slave operation, the slave
must receive the actual values from an additional network analyzer. This network analyzer
must record the values of the part of the PV power plant that is to be controlled. For cascade
control, therefore, an additional network analyzer is required for each slave.
The reactive power setpoints are processed by the slave's own controller.
2 The reactive power setpoints are processed by the controller of the master and transmitted as
output values to the slave. The slave does not control but transmits the output values to the
inverters.
The active power setpoints are processed by the slave's own controller.
3 The active and reactive power setpoints are processed by the controller of the master and
transmitted as output values to the slave. The slave does not control but transmits the output
values to the inverters.