This question already has an answer here:

With a private Ethereum Proof-of-Authority network set up containing 3 sealer nodes, what can we do to estimate the TPS (Transactions per second) of the POA network?

marked as duplicate by TC8, Achala Dissanayake, Richard Horrocks, Ismael, flygoing Jul 19 '18 at 1:42

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.