101+ Power Supply Engineering Terms and Definitions: The Ultimate Guide for Board Exam

Are you struggling to memorize countless power supply terms for your upcoming board exam? You’re not alone. Many engineering students find themselves drowning in technical jargon, flipping through textbooks late at night, and wondering which concepts will actually appear on the exam.

Power supply systems form the backbone of electrical engineering, and examiners consistently test these fundamentals. Yet most study materials either oversimplify critical concepts or bury important definitions in dense, technical language that’s hard to retain.

This comprehensive guide cuts through the confusion. I’d compiled 110+ essential power supply terms and definitions specifically targeted for board exam preparation. Each term is explained in clear, straightforward language that’s technically accurate yet easy to understand and remember.

As a former board exam taker myself, I know the pressure of trying to predict what will appear on the test. That’s why I’ve organized these terms into logical sections based on their frequency in past exams. Whether you’re reviewing basic rectification principles or need to understand advanced power factor correction techniques, this guide provides the precise knowledge you need to answer with confidence.

Don’t waste valuable study time searching through multiple sources. Bookmark this page, review these definitions regularly, and approach your exam with the certainty that you’ve mastered the essential vocabulary of power supply engineering.

Basic Power Supply Concepts

1. Power Supply: An electronic device that supplies electrical energy to an electrical load, converting available power from a source to the correct voltage, current, and frequency needed by the load.

2. AC Power Supply: A power supply that delivers alternating current (AC) where the electric charge periodically reverses direction, typically from utility grid sources.

3. DC Power Supply: A power supply that delivers direct current (DC) where the electric charge flows in only one direction, commonly used in electronic devices.

4. Linear Power Supply: A power supply that uses a linear regulator to provide a stable DC output voltage by dissipating excess power as heat.

5. Switching Power Supply: A power supply that uses switching regulators to efficiently convert electrical power, offering higher efficiency than linear supplies by rapidly switching between on and off states.

6. Uninterruptible Power Supply (UPS): A device providing emergency power when the input power source fails, protecting connected equipment from power disruptions.

7. SMPS (Switched-Mode Power Supply): A power supply incorporating a switching regulator that efficiently converts electrical power by rapidly switching between full-on and full-off states.

8. Voltage Regulation: The ability of a power supply to maintain a constant output voltage regardless of changes in load current or input voltage.

9. Current Regulation: The ability of a power supply to maintain a constant output current regardless of changes in load resistance or input voltage.

10. Transient Response: The ability of a power supply to respond to sudden changes in load current while maintaining output voltage stability.

Power Supply Components

11. Transformer: An electrical device that transfers electrical energy between two or more circuits through electromagnetic induction.

12. Rectifier: A device or circuit that converts alternating current to direct current by allowing current to flow in only one direction.

13. Filter: A circuit element that removes ripple and noise from the output of a rectifier in a power supply.

14. Regulator: A circuit that maintains a constant output voltage or current despite variations in input voltage or load conditions.

15. Feedback Loop: A control mechanism in power supplies that compares the output with a reference value to maintain regulation.

16. Heat Sink: A passive component that enhances heat dissipation from hot components in power supplies, protecting them from overheating.

17. Capacitor Bank: A group of capacitors connected in parallel or series to store electrical energy and filter voltage fluctuations.

18. Inductor: A passive electronic component that stores energy in a magnetic field when electric current flows through it, used in power supply filters.

19. Diode Bridge: An arrangement of four diodes connected to provide the same polarity of output voltage regardless of input polarity.

20. Choke: An inductor used in power supplies to filter out high-frequency noise and smooth current flow.

Rectification and Conversion

21. Half-Wave Rectification: A rectification process where only half of the AC waveform passes through to the output, resulting in pulsed DC.

22. Full-Wave Rectification: A rectification process where both halves of the AC waveform are converted to DC, resulting in more efficient power conversion.

23. Bridge Rectifier: A circuit using four diodes arranged in a bridge configuration to convert AC to DC using both halves of the AC cycle.

24. Center-Tapped Rectifier: A full-wave rectifier using a center-tapped transformer and two diodes to convert AC to DC.

25. Ripple Voltage: The residual periodic variation in the DC output voltage of a power supply resulting from incomplete suppression of the alternating waveform.

26. Smoothing Circuit: A filter circuit, typically using capacitors, designed to reduce ripple voltage in rectified power supplies.

27. Power Factor Correction (PFC): A technique to improve the power factor of a power supply by making the input current waveform follow the input voltage waveform.

28. Active PFC: Power factor correction achieved using active electronic circuits to shape the input current waveform.

29. Passive PFC: Power factor correction achieved using passive components like inductors and capacitors.

30. Voltage Doubler: A circuit that produces an output voltage approximately twice the peak input voltage, using capacitors and diodes.

Regulation and Control

31. Series Regulator: A voltage regulator that acts as a variable resistor in series with the load, controlling current flow to maintain constant output voltage.

32. Shunt Regulator: A voltage regulator that maintains a constant voltage by diverting excess current around the load.

33. Switching Regulator: A regulator that rapidly switches between on and off states to control energy flow and maintain desired output.

34. PWM (Pulse Width Modulation): A technique used in switching power supplies to control output voltage by varying the width of pulses in a fixed-frequency signal.

35. PFM (Pulse Frequency Modulation): A control technique where the frequency of pulses is varied to regulate power supply output.

36. Buck Converter: A step-down DC-to-DC converter that reduces voltage while increasing current.

37. Boost Converter: A step-up DC-to-DC converter that increases voltage while decreasing current.

38. Buck-Boost Converter: A DC-to-DC converter that can either increase or decrease voltage depending on the duty cycle.

39. Flyback Converter: A DC-to-DC converter using a transformer to store energy temporarily and transfer it to the output.

40. Forward Converter: A DC-to-DC converter where energy is transferred to the output during the on-time of the switching transistor.

Efficiency and Performance

41. Efficiency: The ratio of output power to input power in a power supply, expressed as a percentage.

42. Standby Power: The power consumed by a power supply when it is not supplying any significant power to a load.

43. No-Load Power Consumption: The power drawn by a power supply when connected to the power source but not supplying power to any load.

44. Power Density: The amount of power that can be delivered per unit volume of a power supply.

45. Line Regulation: The ability of a power supply to maintain its specified output voltage despite changes in the input line voltage.

46. Load Regulation: The ability of a power supply to maintain its specified output voltage despite changes in the load current.

47. Cross-Regulation: The effect of load changes on one output affecting the voltage levels of other outputs in multi-output power supplies.

48. Thermal Regulation: The change in output parameters of a power supply due to changes in operating temperature.

49. Output Impedance: The effective resistance of a power supply as seen by the load, affecting transient response.

50. Dynamic Response: The behavior of a power supply when subjected to rapid changes in load or input conditions.

Protection and Safety

51. Overcurrent Protection: A safety feature that limits or shuts down the power supply when the output current exceeds a predetermined level.

52. Overvoltage Protection (OVP): A circuit that protects the load from excessive voltage by shutting down the power supply or crowbarring the output.

53. Undervoltage Protection (UVP): A protection mechanism that shuts down the power supply when the output voltage falls below a specified threshold.

54. Short Circuit Protection: A feature that prevents damage to the power supply when its output terminals are accidentally shorted together.

55. Thermal Protection: A safety mechanism that reduces output power or shuts down the power supply when internal temperature exceeds safe limits.

56. Inrush Current Limiting: A technique to limit the high initial current surge when a power supply is first turned on.

57. Soft Start: A feature that gradually increases the output voltage at startup to reduce stress on components and prevent current surges.

58. Crowbar Circuit: A protection circuit that rapidly places a low-resistance shunt across the power supply output when an overvoltage condition is detected.

59. Isolation: Electrical separation between input and output circuits of a power supply to prevent direct current flow between them.

60. Galvanic Isolation: Complete electrical separation between circuits using components like transformers or optocouplers.

Advanced Power Supply Concepts

61. Resonant Converter: A switching power supply that uses resonant circuits to reduce switching losses and electromagnetic interference.

62. Zero Voltage Switching (ZVS): A switching technique where the power transistor is turned on when the voltage across it is zero, reducing switching losses.

63. Zero Current Switching (ZCS): A switching technique where the power transistor is turned off when the current through it is zero, reducing switching losses.

64. Synchronous Rectification: Using actively controlled MOSFETs instead of diodes for rectification to reduce power losses.

65. Digital Power Supply: A power supply with digital control circuits that allow programmable operation and monitoring.

66. Interleaved Converter: A power supply architecture using multiple parallel power stages operating out of phase to reduce ripple and improve transient response.

67. Current-Mode Control: A regulation technique where the peak inductor current is used as the controlled parameter in the feedback loop.

68. Voltage-Mode Control: A regulation technique where the output voltage is the only parameter used in the feedback control loop.

69. Peak Current Mode Control: A control method where switching occurs when the inductor current reaches a threshold determined by the voltage error amplifier.

70. Average Current Mode Control: A control method where the average inductor current rather than the peak current is regulated.

Power Distribution and Management

71. Power Distribution Unit (PDU): A device fitted with multiple outputs designed to distribute electric power to networking equipment and servers.

72. Voltage Bus: A power distribution pathway that delivers a specific voltage level to multiple circuits or devices.

73. Power Management IC (PMIC): An integrated circuit that manages power requirements of various subsystems within an electronic device.

74. Load Balancing: The distribution of power across multiple sources or phases to optimize efficiency and reliability.

75. Sequencing: The controlled startup or shutdown of multiple power rails in a specific order to ensure proper system operation.

76. Voltage Tracking: A technique where one power rail follows or tracks the voltage of another during startup and shutdown.

77. Margining: The deliberate adjustment of a power supply output voltage above or below its nominal value to test system tolerance.

78. Remote Sensing: A feature that compensates for voltage drops in the connecting wires between a power supply and its load.

79. Hot Swap: The ability to replace or add components without shutting down the power supply or system.

80. Redundant Power Supply: A system with multiple power supplies that can maintain operation if one fails.

Power Quality and Conditioning

81. Power Conditioner: A device that improves the quality of the power delivered to electrical equipment by filtering noise and stabilizing voltage.

82. Line Conditioner: A device that regulates, filters, and suppresses noise in the AC power line to provide clean power to sensitive equipment.

83. Surge Protector: A device designed to protect electrical devices from voltage spikes by either blocking or shorting to ground any unwanted voltages.

84. EMI Filter: A passive electronic device that suppresses conducted electromagnetic interference on power or signal lines.

85. Harmonic Distortion: The presence of frequencies in the output of a power supply that are not present in the input, often measured as Total Harmonic Distortion (THD).

86. Common Mode Noise: Unwanted electrical signals that appear equally on all power supply conductors relative to ground.

87. Differential Mode Noise: Unwanted electrical signals that appear between the power supply conductors.

88. Power Line Communication (PLC): Technology that carries data on the same conductors used for electric power transmission.

89. Ferro-resonant Transformer: A special type of transformer that provides voltage regulation and isolation using the principle of ferro-resonance.

90. Automatic Voltage Regulator (AVR): A device that maintains a constant voltage level automatically.

Specialized Power Sources and Storage

91. Battery Backup: A system that provides emergency power when the main power source fails, using rechargeable batteries.

92. Generator: A machine that converts mechanical energy into electrical energy, often used as backup power.

93. Inverter: A device that converts DC power to AC power, used in battery-based systems and renewable energy applications.

94. Solar Power Supply: A power system that converts sunlight into electricity using photovoltaic cells.

95. Wind Power Supply: A system that converts wind energy into electrical power using turbines.

96. Fuel Cell Power Supply: A power source that generates electricity through an electrochemical reaction between hydrogen and oxygen.

97. Supercapacitor: An energy storage device with higher power density than batteries, used for short-term energy storage in power supplies.

98. Flywheel Energy Storage: A mechanical device that stores rotational energy for power supply applications.

99. Off-Grid Power System: A stand-alone power system not connected to the public electricity network.

100. Grid-Tied Power System: A power system connected to the utility grid, allowing bidirectional power flow.

Emerging Technologies

101. Wireless Power Transfer: Technology that enables power transmission without physical connections using electromagnetic fields.

102. Power over Ethernet (PoE): A technology that allows electrical power to be transmitted along with data on Ethernet cabling.

103. Silicon Carbide (SiC) Power Devices: Wide-bandgap semiconductor devices offering higher efficiency and temperature operation in power supplies.

104. Gallium Nitride (GaN) Power Devices: High-performance semiconductors enabling smaller, faster, and more efficient power supplies.

105. Digital Twin Power Supply: A virtual model of a physical power supply used for simulation, monitoring, and optimization.

106. Energy Harvesting Power Supply: A system that captures small amounts of energy from ambient sources such as light, heat, or vibration.

107. Smart Power Supply: An intelligent power supply with networking capabilities, allowing remote monitoring and control.

108. Adaptive Power Management: Advanced techniques that dynamically adjust power delivery based on real-time load requirements.

109. Multi-Phase Power Supply: A power supply using multiple phases to improve efficiency and reduce ripple in high-current applications.

110. Hybrid Power Supply: A system combining multiple power sources such as solar, battery, and grid power to optimize reliability and efficiency.

Congratulations! You’ve just equipped yourself with over 110 precisely defined power supply terms that regularly appear on engineering board exams. This knowledge doesn’t just help you pass a test—it builds the foundation for your professional engineering career.

Remember, success on the board exam isn’t about memorizing every possible term, but understanding the core concepts these definitions represent. The terms in this guide were carefully selected based on their importance in both exam settings and real-world applications. Focus on making connections between related concepts rather than isolated memorization.

In my years teaching engineering students, I’ve noticed that those who master technical vocabulary early have a distinct advantage—they can understand complex systems more quickly because they speak the language of engineering fluently.

As your exam approaches, I recommend:

• Testing yourself regularly on these definitions
• Explaining key concepts to classmates in your own words
• Drawing simple diagrams to visualize the relationships between terms
• Reviewing this guide the night before your exam for last-minute confidence

The path to becoming a licensed engineer is challenging, but with resources like this, you’re well on your way. Good luck on your board exam! When you see questions about power factor correction, switching regulators, or protection circuits, you’ll be ready to demonstrate your expertise with clarity and precision.

Have questions about specific terms? Need clarification on a concept? Drop a comment below, and we’ll help you clear any remaining doubts before your big day.