MGVCL Exam Paper (30-07-2021 Shift 1)
If a 415 V, 50 Hz, star-connected, three-phase squirrel-cage induction motor is operated from a 415 V, 70 Hz supply, the torque that the motor can now provide while drawing rated current from the supply
increases
reduces
increases or reduces depending upon the rotor resistance
A grid-interactive photovoltaic (PV) system uses solar energy to generate renewable power that charges batteries for use during power failures and feeds power into the electricity grid. Grid-interactive systems are based on their grid-tied and off-grid counterparts.
Carrier current over the power line provides simultaneous tripping of circuit breakers at both ends of the line in one to three cycles. Thereby high-speed fault clearing is obtained, which improves the power system stability. The auto-reclosing simultaneous reclosing signal is sent thereby simultaneous (1 to 3 cycles) reclosing of the circuit breaker is obtained. For simultaneous faults, carrier-current protection provides easy discrimination.
As per answer key "pilot protection" is true but there is mistake the right answer is "none".
Bus Type - Known Parameter - Unknown Parameter Load Bus -P, Q - V, phase angle Generator Bus - P, V (magnitude) - Q, Voltage phase angle Slack Bus Voltage - magnitude and phase angle - P, Q