DRUPS unit

Create a single-answer multiple-choice quiz for Power System Engineers on DRUPS (Diesel Rotary Uninterruptible Power Supply). The quiz must assess both theoretical understanding and practical engineering knowledge. Cover DRUPS fundamentals, electrical power flow, normal operation, utility failure, kinetic-energy ride-through, diesel engine starting and loading, rectifier, inverter, DC link, motor-generator, static bypass, maintenance bypass, synchronization, protection, fault conditions, power quality, load flow, short-circuit behaviour, and troubleshooting. Questions should progress from fundamental concepts to advanced engineering scenarios. Include realistic situations such as utility failure, diesel-start failure, bypass operation, overload, short circuit, loss of synchronization, abnormal voltage/frequency, and restoration of utility supply. Include some numerical questions involving kW, kVA, power factor, current, loading percentage, frequency and fault current where appropriate. Each question must have exactly four plausible options with only one technically correct answer. Avoid questions based purely on memorization. Prefer questions that require the engineer to understand