{"@context":"https://schema.org","@type":"QAPage","mainEntity":{"@type":"Question","name":"Consideration of initial conditions in a state estimation calculation","text":"Hello dear PGM Community!
\nI would like to know if Is it possible to control how the state estimation algorithm starts in PGM?
\nIn Pandapower, there is a “flat” start, i.e., everything starts at 1 p.u. 0°. There it is possible to consider the results of the last cycle.
\nIs it possible in PGM to consider initial conditions for the SE-Calculation? I am considering an iterative-linear solver, but I am open to using another one.
\nThank you in advance for your help.
\nBest regards!
\nDavid
","upvoteCount":1,"answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Hi @davidcano90,
\nThe PGM also assumes a flat start (see e.g. https://power-grid-model.readthedocs.io/en/stable/user_manual/calculations.html#state-estimation). This also is the reason behind the following warning about unobservable systems (which should be fully resolved when PowerGridModel/power-grid-model#1085 is resolved):
\n![\"image\"](\"https://private-user-images.githubusercontent.com/15234327/489405890-457cad43-183a-486e-a495-4f446045f12c.png?jwt=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJnaXRodWIuY29tIiwiYXVkIjoicmF3LmdpdGh1YnVzZXJjb250ZW50LmNvbSIsImtleSI6ImtleTUiLCJleHAiOjE3NzA5NTI3MDgsIm5iZiI6MTc3MDk1MjQwOCwicGF0aCI6Ii8xNTIzNDMyNy80ODk0MDU4OTAtNDU3Y2FkNDMtMTgzYS00ODZlLWE0OTUtNGY0NDYwNDVmMTJjLnBuZz9YLUFtei1BbGdvcml0aG09QVdTNC1ITUFDLVNIQTI1NiZYLUFtei1DcmVkZW50aWFsPUFLSUFWQ09EWUxTQTUzUFFLNFpBJTJGMjAyNjAyMTMlMkZ1cy1lYXN0LTElMkZzMyUyRmF3czRfcmVxdWVzdCZYLUFtei1EYXRlPTIwMjYwMjEzVDAzMTMyOFomWC1BbXotRXhwaXJlcz0zMDAmWC1BbXotU2lnbmF0dXJlPWU2YzI4YzYwN2IwZjI2ODUyZGMzMmFlOWVmMWIzMjllYjlmZDYwYWFiOGFlYmI5NTMyMjBlMjhkZTJhZjg2NGUmWC1BbXotU2lnbmVkSGVhZGVycz1ob3N0In0.MO6sXTqEBJ8TtZloxCrUuXPCtGDz58Aym6n1AmpUDYw\")
\nThe PGM currently assumes all scenarios to be independent. As a result, it is not supported to use the final conditions of the previous calculation as an input for the next iteration.
\nCan I ask what the reason is you would like to do so? Maybe we can come up with an alternative way to achieve what you are looking for, or maybe use this as input for a new potential improvement.
","upvoteCount":1,"url":"https://github.com/orgs/PowerGridModel/discussions/66#discussioncomment-14400562"}}}