Coordinated Transient Voltage Support Considering Induction Motor Dynamics in PV-Integrated Distribution Networks Under Symmetrical Faults

During symmetrical faults in photovoltaic (PV)-integrated distribution networks, induction motor (IM) deceleration elevates reactive-power demand and delays post-fault voltage recovery, whereas conventional voltage-driven support can withdraw prematurely upon initial voltage rebound. To resolve this mismatch, this paper proposes a coordinated transient voltage support (CTVS) strategy that explicitly incorporates IM electromechanical dynamics. A coupled differential-algebraic equation (DAE) model integrating third-order IM dynamics, distributed PV (DPV) DC-link dynamics, and network power balance is formulated, from which a trajectory-local closed-loop Q–V sensitivity is derived to characterize location-dependent support effectiveness. The CTVS controller coordinates critical-bus voltage magnitude, voltage-decrease rate, and rotor slip through fixed spatial participation coefficients under local converter current limits and DC-link voltage feedback. Case studies on a modified IEEE 33-bus feeder under Bus-32 three-phase faults demonstrate that, for the representative 140 ms fault, CTVS suppresses post-fault secondary voltage depression and reduces the sustained recovery delay to 23.85 ms, compared with 342.30 ms for local low-voltage ride-through and 390.85 ms for adaptive Q–V droop control. Matched ablations identify slip-conditioned support persistence as the principal contributor to sustained voltage recovery, whereas the fixed spatial coefficients provide a local allocation advantage under unsaturated conditions rather than a separate large-disturbance recovery benefit under the tested conditions.