Siemens sinamics dcp - Page 402

Operation
7.21 Technological functions
SINAMICS DCP
400 Operating Instructions, 09/2019, A5E34382853K
The MPP tracker comprises the following subfunctions:
● Search interval
● Power calculation
● Current setpoint
● Setting value and setting signal
● Plotting the PV array characteristic
Search interval
The search interval specifies at which time intervals (cycles) the current setpoint will be
changed. The search interval of 2 seconds is set in the factory (p54005).
Power calculation
The actual power is continuously calculated and compared with the power in the previous
cycle.
Current setpoint
The MPP tracker supplies a current setpoint at its output for the DCP (if p55050 = r54021).
The current setpoint is generated via a ramp-function generator; after each cycle (p54005)
the ramp-function generator receives a pulse to count up or count down, and the current
setpoint is then increased or decreased by the current step (p54006).
The ramp-function generator is held when a current limit (p54002), which can be specified
via BICO, is reached.
The current setpoint can be output with either a positive or negative sign depending on which
side of the DCP the PV array is connected (p54009). As standard, the PV array is connected
at side 2, and the current setpoint is negative.
Setting value and setting signal
● Pulse enable:
As long as the pulses are not enabled (r0899.11 = 0), the output (r54021) is set to the
current setpoint for manual operation (p54000).
●
Manual/Automatic operation:
– Automatic mode:
The MPP tracker is active.
The current setpoint of the algorithm (r54020) is available at the output (r54021).
– Manual mode:
The MPP tracker is deactivated.
The current setpoint at output (r54021) can be specified via BICO (p54000).
The output of the algorithm (r54020) is set to the specified current setpoint (p54000).
Switchover between the manual and automatic mode is realized via binector p54001.