Current and Potential Transformers in Protection Schemes

What is the role of current transformers in protection schemes?

• Current transformers increase voltage levels for protective relays.

• Current transformers regulate power flow in the system.

• Current transformers step down high currents to measurable levels for protective relays.

• Current transformers are used to measure voltage levels in the system.

How are potential transformers used in protection schemes?

• To regulate frequency in the power grid

• To measure current flow in the system

• To step down high voltage levels to a safe and measurable level for protective relays.

• To increase voltage levels for protective relays

What are some common applications of current transformers in protection?

• Voltage protection, Phase protection, Temperature protection

• Overcurrent protection, differential protection, ground fault protection

Explain the importance of potential transformers in protecting generators.

• Potential transformers are used to cool generators during operation

• Potential transformers increase generator efficiency by reducing power losses

• Potential transformers regulate the frequency output of generators

• Potential transformers step down high voltage to safe levels for monitoring and control, providing accurate voltage measurements to protective relays.

How do current transformers contribute to the protection of motors?

• Current transformers control the speed of motors based on load conditions.

• Current transformers measure the current flowing through a motor to detect overcurrent conditions and trigger protective devices.

• Current transformers regulate the voltage supplied to motors.

• Current transformers monitor the temperature of motors to prevent overheating.

Describe the role of potential transformers in safeguarding transmission lines.

• Potential transformers step down high voltage to safe levels for measurement and protection.

• Potential transformers are only used for decorative purposes on transmission lines

• Potential transformers increase the voltage on transmission lines

• Potential transformers are used to regulate the flow of electricity on transmission lines

What parameters do current transformers measure in protection schemes?

• Current magnitude, phase angle, frequency, harmonic content

• Speed, torque, efficiency

• Voltage magnitude, power factor, resistance

• Temperature, pressure, humidity

Why is accuracy crucial for potential transformers in protection applications?

• Any deviation in voltage measurement can lead to incorrect relay operations, potentially causing failure to protect the system from faults.

• Potential transformers do not require precise measurements

• Accuracy is not important in protection applications

• Inaccurate measurements have no impact on relay operations

How do current transformers help in detecting faults in transformers?

• Current transformers have no impact on detecting faults in transformers.

• Current transformers measure voltage instead of current for fault detection.

• Current transformers increase the current for monitoring, abnormal decrease indicates faults.

• Current transformers step down the current for monitoring, abnormal increase indicates faults.

What are the key features of potential transformers used for generator protection?

• High accuracy, low phase angle error, high insulation level, ability to withstand high fault currents

• Medium accuracy, medium phase angle error, medium insulation level, ability to withstand low fault currents

• High accuracy, low phase angle error, low insulation level, inability to withstand high fault currents

• Low accuracy, high phase angle error, low insulation level, inability to withstand high fault currents