Title: Module 4 Test, Part 1
Course: WIND 100WH Introduction to Wind Energy > Section: WIND 100WH Introduction to Wind Energy

Q: What does the image above indicate?
- The yaw control system or blade pitch control system loop waveform
- Electrical power generation and the resultant vector and waveform
- Fluctuating wind pattern waveform
- None of the above
A: Electrical power generation and the resultant vector and waveform

Q: What is it called when an electrical source has a waveform that changes polarity?
- Hertz
- Alternating Current
- Frequency
- Direct Current
A: Alternating Current

Q: The amount of time it takes for a sine wave to complete one full alternation is called the _________.
- synchronous time
- asynchronous time
- period
- wave time
A: period

Q: Referring to the figure above, when is the coil producing the most amount of voltage?
- At 35° only
- At 90°, 270°, and so on (when it’s vertical in the magnetic field)
- When it is horizontal within the magnetic field
- None of the above
A: At 90°, 270°, and so on (when it’s vertical in the magnetic field)

Q: The amplitude of the waveform indicates the __________ of the waveform throughout time.
- peak voltage
- time and period
- frequency
- period
A: peak voltage

Q: What is the period of the 60Hz ac waveform?
- 16.7 seconds, or 16.7ms
- 0.016,6 seconds or 16.6ms
- 160 periods, or 160k
- 60Hz
A: 0.016,6 seconds or 16.6ms

Q: To increase magnetic strength of a coil, you must do what to it?
- Add more air within the coil and use larger wire
- Add more loops on the coil in the same amount of area
- Add more shunts to the circuit
- Remove shunts from the circuit
A: Add more loops on the coil in the same amount of area

Q: The shaft and attached components within a generator is called the ___________.
- output shaft
- commutator
- armature
- rotor
A: armature

Q: Brushes and commutator segments provide ____________.
- electrical contact and timing for the generator
- electrical timing for the PLC
- electrical power to the generator
- a decrease in torque as the motor increases in rpm
A: electrical contact and timing for the generator

Q: A motor/generator shaft's bearings are located within the ____________.
- coil
- end plates
- slip ring plates
- drop out plate
A: end plates

Q: What type of generator is most commonly used in older wind turbines because of its ease of connection to the grid?
- ac induction generator
- ac induction generator
- Synchronous generator
- DC induction generator
A: Synchronous generator

Q: The generator used in modern, large turbines that uses multiphase wound rotors is called a/n ____________.
- asynchronous type generator
- synchronous type generator
- doubly-fed generator
- multi-phasor generator
A: doubly-fed generator

Q: What’s the electrical current that flows through the rotor coils of a stationary-armature alternator called?
- Flux inducing current
- Constant (K) current
- Exciter current
- Lossless dampening current
A: Exciter current

Q: What are the two basic functional-parts of an alternator?
- The rotor and stator assembly
- The coil and stator assembly
- The PM coil and rotor assembly
- The field and running-current coil
A: The rotor and stator assembly

Q: What type of motor produces more torque than similarly-sized induction motors? Hint: it uses brushes and slip rings.
- Wound rotor motors
- Steel laminated rotor motors
- ac motors
- Induction motors
A: Wound rotor motors

Q: The cage rotor within a motor/generator is sometimes referred to as a/n ___________.
- laminated steel rotor
- squirrel cage assembly
- All of the above
A: All of the above

Q: The magnetic field of a coil can be increased by doing what?
- By placing lead cores inside the coil
- By making the core larger
- By decreasing the number if coil windings
- By increasing the permeability of the core
A: By increasing the permeability of the core

Q: Dashed lines represent the ___________ of the magnetic fields.
- field poles
- flux lines
- segments
- field connections
A: flux lines

Q: In a magnet, atoms are grouped in regions called _______ regions.
- polarity
- dominant
- dipole
- unipolar
A: dipole

Q: If dipoles are mostly random within a metal, this metal would be a _____________ magnet.
- weak
- strong
- varying core
- random core
A: weak

Q: What’s an advantage of electromagnets over permanent magnets?
- It can be strengthened easily.
- The coil can be turned on or off.
- Most very powerful permanent magnets are expensive.
- All of the above
A: All of the above

Q: A generator, relay, and solenoid utilize the properties of _________.
- electromagnetism
- electronic differentiation
- fluid mechanics
- power mechanics
A: electromagnetism

Q: The amount of rotating force available at the shaft of a motor (or other devices) is called ___________________.
- electrical force
- torque
- pressure grade
- angular power
A: torque

Q: On a separately excited generator, the voltage can come from a/n ______________.
- magnetic field
- battery
- ac source
- power inverter
A: battery

Q: There are three different types of compound generators. The main advantage of these units is that they are able to produce_______, under different loads.
- constant current output
- constant voltage output
- constant electrical flow output
- constant resistance output
A: constant voltage output

Q: A DC PM generator uses a _______________ and a DC wound field generator uses a ______________ as their source of magnetic fields.
- magnet / field coil (an electromagnet)
- battery / coil
- winding / transformer (mutual inductor)
- flux magnet / coil
A: magnet / field coil (an electromagnet)

Q: A wound generator requires an external electrical power source to generator power.
- True
- False
A: True

Q: What is the difference between a generator and an alternator?
- A generator generates electrical power (DC or ac), an alternator is any generator that produces ac.
- A generator generates ac electrical power, an alternator is any generator that produces some form of ac.
- A generator generates DC electrical power, an alternator is any generator that produces some form of ac.
- A generator generates electrical power (DC or ac), an alternator is not a generator.
A: A generator generates electrical power (DC or ac), an alternator is any generator that produces ac.

Q: A three-phase motor is basically three single-phase motor armatures placed how many degrees apart?
- 300°
- 120°
- 250°
- 330°
A: 120°

Q: A generator, or alternator, cannot produce more mechanical power than the equivalent input power. What is this called? The use
of percentages for efficiency in power equations and other equations are called what?