Power Systems and FACTS Controllers Practice Questions PDF

Unit - IV / Part - A / 1 Marks Sl. Questions No. 1. In an IUPQC system, how are the series and shunt Voltage Source Converters (VSCs) connected to the feeders? (a) Both VSCs are connected in series to both feeders (b) Both VSC...

Unit - IV / Part - A / 1 Marks Sl. Questions No. 1. In an IUPQC system, how are the series and shunt Voltage Source Converters (VSCs) connected to the feeders? (a) Both VSCs are connected in series to both feeders (b) Both VSCs are connected in shunt to both feeders (c) VSC-1 is connected in shunt to feeder-1, and VSC-2 is connected in series with feeder-2 (d) VSC-1 is connected in series with feeder-1, and VSC-2 is connected in shunt to feeder- 2 2. Which control strategy for DVRs results in the minimum value of the injected voltage magnitude? (a) Pre-Sag Compensation (b) In-phase Compensation (c) Minimum Energy Compensation (d) Maximum Sag Compensation 3. Which device is commonly used in DVRs for fast response? (a) Thyristor (b) IGBT or IGCT (c) Relay (d) Transformer 4. What is the primary function of a Dynamic Voltage Restorer (DVR)? (a) To increase power generation efficiency (b) To compensate for voltage sags and swells (c) To reduce the cost of electricity (d) To enhance the physical security of power systems 5. What is the observed effect on the DC capacitor voltage when IUPQC is implemented, according to the experimental results? (a)The DC capacitor voltage becomes highly unstable (b)The DC capacitor voltage shows no noticeable change (c)There is a significant drop in the DC capacitor voltage (d) The DC capacitor voltage remains stable 6. Which components are combined to form a UPQC? (a) DVR and DSTATCOM (b) STATCOM and SSSC (c) TCSC and UPFC (d) FACTS and Energy Storage 7. What does the series-connected converter in a UPQC aim to control? (a) The harmonic content in the source current (b) The magnitude of the load bus voltage (c) The DC bus voltage (d) The energy storage capacity of the system 8. How does the UPQC manage to regulate the load bus voltage? (a) By injecting variable active voltage in phase with the source current  (b) By providing long-term energy storage solutions (c) By enhancing the power factor of the system (d) By increasing the voltage level for high-capacity transmission 9. What is the main control objective of the shunt-connected converter in UPQC? (a) To increase the transmission capacity of power lines (b) To store electrical energy for future use (c) To regulate the DC bus voltage and balance the source currents (d) To compensate for voltage sags and swells at the load bus 10. A DSTATCOM operates at a point where the V-I characteristics are linear. If the susceptance (B) of the system is increased while keeping the voltage constant, how does the reactive power (Q) change? (a) Q increases proportionally with B (b) Q decreases proportionally with B (c) Q remains constant despite changes in B (d) Q increases with the square of B 11. Which control strategy is typically used for the operation of DSTATCOM in a distribution network? (a) Direct Torque Control (b)Vector Control (c) Slip Ring Control (d) V/f Control 12. What is the primary purpose of a DSTATCOM in a power distribution network? (a) To generate electrical power (b) To compensate for reactive power (c) To transmit electrical power over long distances (d) To convert AC power to DC power 13. What does the vector diagram of DSTATCOM indicate when reactive power is supplied? (a) VI leads I (b) VI lags I (c) VI is in phase with I (d) VI and I are not related 14. What components are included in a DSTATCOM system? (a) VSI and an ac filter (b) dc energy storage device (c) Coupling transformer (d) All of the mentioned 15. In the context of UPQC, what does the term `PCC` stand for? (a) Power Conversion Circuit (b) Power Control Center (c) Point of Common Coupling (d) Power Charge Controller 16. What is the primary function of the Voltage Source Converters (VSCs) in an IUPQC system? (a) To store energy (b) To convert mechanical energy into electrical energy (c)To connect back to back through a common energy storage dc capacitor (d) To supply power to residential areas 17. What are the two main problems IUPQC aims to solve in the power distribution system? (a) Energy storage and conversion (b) Voltage sags and equipment efficiency (c) Harmonic elimination and swell mitigation (d) Power generation and transmission 18. What functions does the shunt bidirectional converter perform in an IUPQC system? (a) Only injects reactive current to compensate current harmonics (b) Only provides reactive power to improve the power factor (c) Draws fundamental current and compensates for power loss (d) All of the above 19. How does the IUPQC improve power quality in two feeders? (a) By transmitting power over long distances (b) By regulating bus voltage and load current (c) By converting AC power to DC power (d) By increasing the power output of generators 20. What technology is used in IUPQC for generating gating signals? (a) Direct Torque Control (b) Sinusoidal Pulse Width Modulation (PWM) (c) Vector Control (d) Multilevel Inverter Control Unit - V / Part - A / 1 Marks/MCQ Sl.No. Questions 1. Considering the integration of renewable energy sources into the grid, how do adaptive controllers in FACTS need to evolve? (a) They should become more static to ensure stability with the unpredictable nature of renewable sources. (b) Adaptive controllers must evolve to handle the increased variability and intermittency of power generation from renewable sources. (c) There's no need for evolution; current controllers are fully equipped to handle such integration. (d) The focus will shift entirely to energy storage rather than adapting to generation variability. 2. What potential issue must be carefully managed when implementing an adaptive controller in a FACTS device?  (a) Oversimplification of the system model (b) Overfitting the controller to specific operational scenarios (c) Risk of instability due to rapid parameter changes (d) Reduction in the quality of power supplied to the end-users 3. What role does an adaptive controller play in the dynamic compensation of FACTS devices? (a) It decreases the system's ability to respond to load changes. (b) It maintains a constant power flow under static conditions only. (c) It dynamically adjusts the compensation based on load variations and system disturbances. (d) It simplifies the network topology for easier management. 4. How do adaptive controllers in FACTS contribute to the mitigation of power system oscillations? (a) By statically setting system parameters to their optimal values. (b) Through continuous real-time adjustment of control parameters to dampen oscillations effectively. (c) By disconnecting the oscillating parts of the system. (d) Using only passive network elements for oscillation suppression. 5. In the context of FACTS, what is the advantage of using online learning algorithms in adaptive controllers? (a) They eliminate the need for any form of feedback mechanism. (b) They can improve control strategies in real-time by learning from the system's current state and performance. (c) They significantly reduce the computational power needed for control. (d) Online algorithms are solely used for their ability to operate without internet connectivity. 6. What is a potential drawback of using a dead-beat controller in FACTS devices? (a) It can only be used in digital systems. (b) It may lead to overshoot or instability in the presence of model inaccuracies or unmodeled dynamics. (c) It is incompatible with renewable energy sources. (d) It significantly increases the operation costs due to energy inefficiency. 7. Which of the following is a key advantage of using a dead-beat controller in FACTS devices? (a) It requires no knowledge of the system model. (b) It ensures that the control action is executed over an indefinite number of sampling periods. (c) It provides quick response and precise control over the system parameters. (d) It is only applicable for linear systems. 8. What is the primary purpose of using FACTS (Flexible AC Transmission Systems) in power systems?  (a) To increase the power generation capacity. (b) To control power flow and improve the stability and efficiency of power transmission systems. (c) To reduce the cost of electricity. (d) To replace traditional transformers. 9. Which of the following is a key benefit of implementing adaptive controllers in FACTS? (a) Reduction in physical size of FACTS devices (b) Improved system stability and adaptability to varying network conditions (c) Complete automation of the power distribution network (d) Elimination of the need for system protection devices 10. The participation factor in a damping controller design indicates: (a) The fraction of total power controlled by the damping controller (b) The contribution of a state variable to a particular oscillation mode (c) The efficiency of power usage by the controller (d) The impact of the controller on the system's reactive power 11. In the context of damping control, what does the term 'modal controllability factor' signify? (a) The capability of a controller to regulate power flow (b) The effectiveness of a controller in influencing specific oscillation modes (c) The resistance of a controller to external disturbances (d) The efficiency of a controller in converting electrical to mechanical energy 12. What is the primary objective of tuning supplementary modulation controllers (SMCs) in power systems? (a) To minimize the real parts of all eigenvalues in the system (b) To maximize the transfer function gain at the fundamental frequency (c) To optimize damping across several critical swing modes (d) To ensure maximum power transfer capability 13. What is the purpose of tuning supplementary modulation controllers (SMCs) in power systems? (a) To adjust the voltage levels across the network (b) To manage the power flow in transmission lines (c) To damp critical swing modes and improve stability (d) To increase the reactive power compensation 14. In the analysis of damping of power oscillations using series FACTS controllers, which assumption is NOT made? (a) The real power drawn by loads varies linearly with bus frequency (b) The bus voltage magnitudes are constants (c) The mechanical damping is considered in the generator models (d) The electrical network is assumed to be lossless 15. Which component is essential in a feedback control system to modulate the value of TCSC reactance?  (a) Transfer function (b) Eigenvalue (c) System input (u) (d) Power Oscillation Damping (POD) 16. What does the matrix [K] represent in the swing equation? (a) Kinetic energy matrix (b) Modal inertia matrix (c) Stiffness matrix evaluated at the equilibrium point (d) Damping coefficient matrix 17. What is the primary purpose of a Power Swing Damping Controller (PSDC)? (a) To increase power generation (b) To damp oscillations in power systems (c) To enhance power transmission efficiency (d) To reduce the cost of electricity 18. In the context of modal transformation of swing equations, what is the significance of the transformation matrix [Q]? (a) It represents the eigenvalues of the system (b) It allows for the diagonalization of matrices [M] and [K] (c) It denotes the mechanical damping in the system (d) It indicates the power output of the generators 19. What does the NPI (Negative Phase Indicator) index provide information on? (a) The amount of reactive power controlled by the damping controller (b) The phase information on the eigenvalue shift due to the controller (c) The efficiency of power usage by the controller (d) The impact of the controller on the system's power transfer capacity 20. What is the primary objective of designing damping controllers in power systems? (a) To increase the power transfer capacity (b) To improve system stability by damping oscillations (c) To reduce the overall cost of electricity (d) To enhance the efficiency of power generation