Easier way to change load and gen values and export to excel

answered 2012-08-03 03:10:30 -0500

JervisW
1298 ●20 ●34 ●55

updated 2012-08-08 01:37:10 -0500

Here is a tutorial for learning Python for PSSE. I'm constantly improving it, message me if you have any ideas.

But to address your immediate problem this is a script that completes the following steps:

1. Read the load power and generator power for specific bus and machine ids from a CSV file
2. Update the loads and generators with their new values in PSSE
3. Export bus voltages into a single spreadsheet

Here it is:

"""
Change the load and generation levels in a PSSE case.
Assume that the CSV file has the following headings:

load?, p, q, bus, id

so for a load entry it reads:
1, 200, 150, 20045, 2

and for a generator entry it could look like:
0, 600, 0, 20020, C

We can change many loads and files in the same file, just by adding new rows!
"""
import csv

import psspy
psspy.throwPsseExceptions = True

LOAD_GEN_DATAFILE = 'c:/studies/2012/load-and-gen-data.csv'
STUDY_CASE = 'c:/studies/2012/top-secret-new-generator.sav'
OUTPUT_VOLTAGES = 'c:/studies/2012/new-bus-voltages.csv'

psspy.case(STUDY_CASE)

# read the entire CSV into Python.
data = list(csv.reader(open(LOAD_GEN_DATAFILE)))

# assume CSV has columns as described in the doc string
for isload, p, q, bus, _id in data:
        # convert the types from string to Python numbers
        p = float(p)
        q = q.isdigit() and float(q)
        bus = int(bus)

        if isload.isdigit() and int(isload):
            psspy.load_data_3(bus, _id, realar1=p, realar2=q)
        else:
            psspy.machine_data_2(bus, _id, realar1=p)

    # solve case after adding all loads / machines.
    psspy.fnsl()

# now to write the new bus voltages to a file.
ierr, (voltages,) = psspy.abusreal(sid=-1, string=["PU"])
ierr, (buses,) = psspy.abusint(sid=-1, string=["NUMBER"])

csvfile = open(OUTPUT_VOLTAGES, 'wb')
writer = csv.writer(csvfile)

for row in zip(buses, voltages):
    writer.writerow(row)

csvfile.close()

Try this out, I haven't got a copy of PSS/E here to see if it works myself :)