Before revision: Four variables are associated with each bus: voltage |V| phase angle |δ| active or real power |P| reactive power |Q| Based on these values, a bus may be classified into the above-mentioned three categories as - P Q V δ P-V bus known known unknown unknown P-V bus known unknown known unknown Slack bus unknown unknown known known Real and reactive powers (i.e.
After revision: Four variables are associated with each bus: voltage |V| phase angle |δ| active or real power |P| reactive power |Q| Based on these values, a bus may be classified into the above-mentioned three categories as - P Q V δ P-Q bus known known unknown unknown P-V bus known unknown known unknown Slack bus unknown unknown known known Real and reactive powers (i.e.