Within a high-voltage direct current (HVDC) transmission system utilizing gas circuit breakers, which condition most reliably triggers transient voltage instability?

💡 Explanation

Unexpected load rejection increases DC link voltage; therefore, the Gas Circuit Breaker's (GCB) interruption generates high-frequency oscillations due to distributed inductance and capacitance of the line and converter transformers, rather than inductor saturation which changes impedance.

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