Power system stability evaluation method, device and equipment and storage medium

The invention discloses a power system stability evaluation method, device and equipment and a storage medium. An algebraic manifold is eliminated through network order reduction, and a polynomial ordinary differential equation system for describing the transient voltage stability dynamic process of the power system is obtained; according to the polynomial differential equation set system, based on an extended interior domain method, establishing a first quadratic sum planning problem and a second quadratic sum planning problem by fixing values of different variables; through a quadratic sum planning method, repeatedly and iteratively solving the first quadratic sum planning problem and the second quadratic sum planning problem in sequence, and obtaining a stability domain of the transient voltage of the power system; and acquiring a first state variable of the power system at the current moment, and determining that the power system is in an unstable state when the first state variable is located outside the