HVDC (High Voltage Direct Current) Systems MCQs December 23, 2025July 15, 2024 by u930973931_answers 50 min Score: 0 Attempted: 0/50 Subscribe 1. What does HVDC stand for? (A) High Voltage Distributed Current (B) High Voltage Direct Current (C) High Voltage Discharge Capacitor (D) High Velocity Direct Converter 2. Which of the following is a key advantage of HVDC over HVAC (High Voltage Alternating Current)? (A) Lower efficiency (B) Higher transmission losses (C) Lower cost of installation (D) Limited transmission distance 3. In HVDC systems, what is the purpose of using converters? (A) To convert AC to DC and vice versa (B) To store electrical energy (C) To control voltage fluctuations (D) To connect transformers 4. Which component is used to convert DC to AC in an HVDC system? (A) Transformer (B) Converter (C) Rectifier (D) Inverter 5. What is the typical voltage level used in HVDC transmission? (A) Below 100 kV (B) Around 230 kV (C) Above 500 kV (D) 1000 V 6. Which type of HVDC system uses two separate lines for transmitting power in opposite directions? (A) Bipolar HVDC (B) Monopolar HVDC (C) Back-to-back HVDC (D) Symmetrical HVDC 7. What is the primary advantage of a monopolar HVDC system? (A) Lower transmission losses (B) Simplicity in installation (C) Reduced environmental impact (D) Higher power transmission capacity 8. In an HVDC system, what is the purpose of the grounding electrode at the converter station? (A) To regulate voltage levels (B) To protect against lightning strikes (C) To provide a return path for current (D) To increase system efficiency 9. Which type of HVDC transmission is used to connect two asynchronous AC systems operating at different frequencies? (A) Back-to-back HVDC (B) Monopolar HVDC (C) Bipolar HVDC (D) Series HVDC 10. In an HVDC system, which component controls the flow of power between the AC and DC sides? (A) Transformer (B) Converter (C) Rectifier (D) Inverter 11. Which of the following is a disadvantage of HVDC transmission compared to HVAC transmission? (A) Higher losses over long distances (B) Lower efficiency (C) Limited capacity for power transmission (D) Higher cost of installation 12. In an HVDC system, what is the typical frequency of DC transmission? (A) 50 Hz (B) 60 Hz (C) 0 Hz (D) 100 Hz 13. Which factor limits the maximum transmission distance of HVAC systems? (A) Voltage level (B) Current carrying capacity (C) Line impedance (D) Both A and B 14. What is the approximate efficiency of HVDC transmission lines compared to HVAC lines? (A) Lower (B) Higher (C) Equal (D) Cannot be determined 15. Which of the following is not a typical application of HVDC technology? (A) Long-distance power transmission (B) Undersea power cables (C) Residential power distribution (D) Connecting asynchronous power grids 16. Which type of HVDC system uses a ground electrode on one side and a conductor on the other for power transmission? (A) Bipolar HVDC (B) Monopolar HVDC (C) Series HVDC (D) Back-to-back HVDC 17. What is the primary function of the smoothing reactor in an HVDC system? (A) To control power flow (B) To maintain a constant DC voltage (C) To improve efficiency (D) To convert AC to DC 18. Which statement about HVDC transmission is true? (A) It is limited to short-distance applications. (B) It is less expensive than HVAC transmission. (C) It does not require converter stations. (D) It has lower efficiency compared to HVAC transmission. 19. Which of the following is a challenge associated with HVDC transmission lines? (A) Lower capacity for power transmission (B) Higher risk of electric shock (C) Difficulty in synchronizing with AC grids (D) Limited applications in renewable energy systems 20. What is the purpose of the bypass switch in an HVDC converter station? (A) To switch between AC and DC modes (B) To bypass the DC line during maintenance (C) To regulate voltage levels (D) To synchronize with the AC grid 21. Which type of HVDC system is used for connecting two AC systems of different frequencies? (A) Bipolar HVDC (B) Monopolar HVDC (C) Series HVDC (D) Back-to-back HVDC 22. In a bipolar HVDC system, what is the purpose of the metallic return electrode? (A) To reduce power losses (B) To provide a ground path for the return current (C) To increase transmission capacity (D) To regulate voltage fluctuations 23. Which component is used to smooth the DC voltage in an HVDC transmission system? (A) Inverter (B) Rectifier (C) Capacitor (D) Transformer 24. Which of the following factors contributes to the high efficiency of HVDC transmission? (A) Lower resistance losses (B) Higher magnetic losses (C) Higher dielectric losses (D) None of the above 25. Which type of HVDC system is used for point-to-point transmission over long distances? (A) Series HVDC (B) Back-to-back HVDC (C) Monopolar HVDC (D) Bipolar HVDC 26. What is the primary advantage of using HVDC for undersea cable transmission? (A) Lower installation cost (B) Higher efficiency (C) Ability to transmit AC directly (D) Reduced electrical losses 27. In an HVDC system, what is the typical frequency of AC voltage before conversion? (A) 0 Hz (B) 50 Hz (C) 60 Hz (D) 400 Hz 28. Which type of HVDC system is used to improve system stability and power flow control? (A) Monopolar HVDC (B) Back-to-back HVDC (C) Series HVDC (D) Bipolar HVDC 29. What is the primary disadvantage of monopolar HVDC systems compared to bipolar HVDC systems? (A) Higher transmission losses (B) Limited power capacity (C) Need for additional ground electrodes (D) Lower efficiency 30. Which statement about HVDC technology is true? (A) It is primarily used for short-distance transmission. (B) It operates only at low voltage levels. (C) It is more expensive than HVAC transmission. (D) It allows asynchronous interconnection of power grids. 31. What is the function of the transformer in an HVDC converter station? (A) To convert DC to AC (B) To convert AC to DC (C) To step up or step down voltage (D) To provide grounding 32. Which type of HVDC system is used for connecting renewable energy sources to the grid? (A) Series HVDC (B) Back-to-back HVDC (C) Monopolar HVDC (D) Bipolar HVDC 33. In a bipolar HVDC system, what is the purpose of the metallic return path? (A) To control power flow (B) To provide a ground path for the return current (C) To increase transmission capacity (D) To synchronize with the AC grid 34. Which of the following is a benefit of using HVDC technology for long-distance transmission? (A) Lower cost (B) Higher transmission losses (C) Lower electrical losses (D) Limited power capacity 35. Which component is used to convert DC to AC in an HVDC system? (A) Rectifier (B) Inverter (C) Converter (D) Transformer 36. Which type of HVDC system uses a solid ground return path? (A) Monopolar HVDC (B) Bipolar HVDC (C) Back-to-back HVDC (D) Series HVDC 37. What is the primary advantage of using HVDC technology for renewable energy integration? (A) Higher efficiency (B) Lower installation cost (C) Direct compatibility with AC grids (D) Ability to transmit power over long distances 38. In an HVDC system, what is the function of the smoothing reactor? (A) To convert DC to AC (B) To regulate voltage levels (C) To step up or step down voltage (D) To provide grounding 39. Which of the following is a characteristic of HVDC transmission lines? (A) High losses at low voltage (B) High losses at high voltage (C) Low losses at low voltage (D) Low losses at high voltage 40. Which type of HVDC system is used to connect two asynchronous AC grids operating at different frequencies? (A) Back-to-back HVDC (B) Monopolar HVDC (C) Bipolar HVDC (D) Series HVDC 41. What is the purpose of using converters in an HVDC system? (A) To convert AC to DC and vice versa (B) To store electrical energy (C) To control voltage fluctuations (D) To connect transformers 42. Which component is used to convert DC to AC in an HVDC system? (A) Transformer (B) Converter (C) Rectifier (D) Inverter 43. What is the typical voltage level used in HVDC transmission? (A) Below 100 kV (B) Around 230 kV (C) Above 500 kV (D) 1000 V 44. Which type of HVDC system uses two separate lines for transmitting power in opposite directions? (A) Bipolar HVDC (B) Monopolar HVDC (C) Back-to-back HVDC (D) Symmetrical HVDC 45. What is the primary advantage of a monopolar HVDC system? (A) Lower transmission losses (B) Simplicity in installation (C) Reduced environmental impact (D) Higher power transmission capacity 46. In HVDC systems, what is the purpose of using converters? (A) To convert AC to DC and vice versa (B) To store electrical energy (C) To control voltage fluctuations (D) To connect transformers 47. Which component is used to convert DC to AC in an HVDC system? (A) Transformer (B) Converter (C) Rectifier (D) Inverter 48. What is the typical voltage level used in HVDC transmission? (A) Below 100 kV (B) Around 230 kV (C) Above 500 kV (D) 1000 V 49. Which type of HVDC system uses two separate lines for transmitting power in opposite directions? (A) Bipolar HVDC (B) Monopolar HVDC (C) Back-to-back HVDC (D) Symmetrical HVDC 50. What is the primary advantage of a monopolar HVDC system? (A) Lower transmission losses (B) Simplicity in installation (C) Reduced environmental impact (D) Higher power transmission capacity