WTT Control Systems & SCADA 2

Question 1

In a wind turbine SCADA system, what does the term 'polling interval' refer to?

Accepted Answer

The frequency at which the SCADA system queries RTUs or PLCs for data

Answer

Polling interval is the frequency at which the SCADA master station requests updated data from remote terminal units (RTUs) or PLCs.

Question 2

Which communication protocol is most commonly used for serial communication between SCADA systems and older wind turbine controllers?

Accepted Answer

Modbus RTU

Answer

Modbus RTU is the most widely used serial communication protocol for legacy SCADA-to-controller communication in wind turbines due to its simplicity and broad device support.

Question 3

A wind turbine's yaw control system uses a 'yaw error' signal. What does this signal represent?

Accepted Answer

The angular difference between the nacelle heading and the wind direction

Answer

Yaw error is the angular difference between the nacelle's current heading and the measured wind direction, used to command the yaw drive to realign the rotor with the wind.

Question 4

What is the purpose of a 'deadband' setting in a wind turbine PID controller?

Accepted Answer

To prevent the controller from responding to small, insignificant error signals

Answer

A deadband prevents the controller from making unnecessary corrections when the error signal is within an acceptable range, reducing actuator wear.

Question 5

Which sensor is primarily used to provide feedback for closed-loop pitch control in modern wind turbines?

Accepted Answer

Encoder or resolver on the pitch bearing or motor

Answer

An encoder or resolver mounted on the pitch motor or bearing provides precise blade angle position feedback to the pitch controller for closed-loop control.

(WTT) Wind Turbine Technician Certification Practice Test

(WTT) Wind Turbine Technician Certification Practice Test

WTT Control Systems & SCADA 2