Term 2 Flashcards
(179 cards)
1
Q
What is an Electricity Grid?
A
Network of synchronised power generators connected to customers by transmission lines and distribution systems.
2
Q
Define a Generation System
How are generation systems classified
A
Where electrical Power is generated from different types of energy sources
Non-Renewable / Renewable
Conventional/ Non-Conventional
3
Q
Define a transmission System
A
Network of power lines and substations that transport electrical energy from generation facilities to distribution networks over long distances
4
Q
What impacts does increasing the voltage have on a transmission system?
A
P loss = I^2R
P Transmitted = VXI
Increase power transmitted between sending a receiving ends
Reduce Power Losses
5
Q
Evaluate OHTL and UGTL
A
OGTL - Overground Transmission Lines
More Cost Effective, Easier to Maintain, Vulnerable to weather
UGTL -underground transmission lines
More reliable and Durable , Harder and more costly to repair
6
Q
What are the Advantages and Disadvantages of a HVAC Transmission System
A
Advantages
Transformers can be used
Circuit Breaker –> Failsafe
Cheaper at Short Distances
Easy Control
Disadvantages
Stability
Skin Effect
More Cables
Reactance’s introduced
Reactive Power Loss
Limits on Power ( v1v2sin(phase)/ Xl)
7
Q
What are the Advantages and Disadvantages of a HVDC Transmission System
A
Advantages
Fewer Cables
Cheaper in Long Distances
No Skin Effect (Thinner Cables)
No Synchronisation necessary (Stability)
No Reactance
No Reactance Power Loss
Disadvantages
Requires Rectifiers at the Sending ed; inverters at the receiving end
Complicated Novel System
Much more complex DC circuit breakers required
Cost
Hard to Control
8
Q
Derive the Limit on Power for AC Tranmission?
A
9
Q
A
10
Q
derive Line voltage
A
11
Q
Define power electronics
A
use of electronic components, circuit theory, design techniques and analytical tools to control, condition and convert electrical power
12
Q
Calculate the efficiency of a linear regulator power converter that steps down the voltage from 12V to 5V
(buck converter)
A
13
Q
What function do the following converters serve:
Rectifier Cycloconverter DC/DC converter Inverter
A
Rectifier: Converts AC (alternating current) to DC (direct current) for use in devices that require a steady DC supply.
Cycloconverter: Directly converts AC power from one frequency to another, enabling variable frequency control for AC motors.
DC/DC Converter: Converts one DC voltage level to another, allowing different parts of a system to operate at different voltage levels.
Inverter: Converts DC (direct current) to AC (alternating current), often used to supply power to AC devices from a DC source like a battery.
14
Q
Draw a Single Phase Diode Rectifier (1A Half-Wave)
A
Negative half cycles are blocked
15
Q
Draw a Single Phase Diode Rectifier (1B Full-Wave)
A
Negative and positve half cycles are used
16
Q
Draw a Three-phase dioide rectifier (1C)
A
17
Q
Draw a single-phase H-Bridge Inverter (2A)
A
18
Q
Draw a three phase Inverter (2B)
A
19
Q
What is the difference between direct (3A) and indirect (3B) converters
A
Direct:
No Intermediate DC Stage
Lower cost
Higher Efficiency
more harmonic distortion
Complex Control required
Indirect:
Intermediate DC Stage
Can produce higher and lower frequencies (Direct only does lower)
Less harmonic distortion
higher cost
Lower efficiency
20
Q
Draw a Buck Converter
Derive the voltage transfer function of a Buck Converter
How do you control a Buck Converter
A
Use a PI Controller to apply a pwm signal to the gate of the transistor (mosfet), use negative feedback to adjust the PWM duty cycle at the base.
21
Q
Draw a Boost Converter
Derive the voltage transfer function of a Boost Converter
How do you control a Boost Converter
A
Use a PI Controller to apply a pwm signal to the gate of the transistor (mosfet), use negative feedback to adjust the PWM duty cycle at the base.
22
Q
Draw a Voltage agaisnt time plot of a boost converter
Explain how the efficiency and quality of the waveform can be improved
A
23
Q
What is the function of a buck-boost converter
A
A buck-boost converter can either increase or decrease the input voltage to maintain a stable output voltage.
24
Q
Draw a Buck-Boost Converter
Derive the voltage transfer function of a Buck-Boost Converter
How do you control a Buck-Boost Converter
A
Use a PI Controller to apply a pwm signal to the gate of the transistor (mosfet), use negative feedback to adjust the PWM duty cycle at the base.
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what is the base rotational speed, and max armature voltage of a motor (sep-ex)
Base Rotational Speed of a Motor: The speed at which a motor runs when connected to the rated voltage and delivering the rated torque.
Max Armature Voltage: The highest voltage that can be applied to the armature of a motor without causing damage or excessive wear.
Base Rotational speed is running at a Va Max --> however this maybe wrong in reality
29
what is Max Speed of a DC Motor (sep-ex)
The angular velocity of a motor without a load
30
How does the power of a motor change as speed increases (sep-ex)
Power kept constant
Torque decreases at same rate to increase in speed
31
Draw a torque-speed and power speed graph for a spex ex motor
-Armature voltage control occurs first then field control
Give an advantage for the control of this type of motor
Armature voltage and field current are independent
more flexible control of speed and torque compared with other motors
32
Describe a way the armature voltage and field current is control in a sep-ex motor
Controlled by Buck, Boost and Buck-boost converters
33
What's a disadvantage to using a buck converter for DC Motor control
Unidirectional Speed Control (DC motor cant go in reverse)
34
Draw and name a solution for bidirectional motor control
H-Bridge Chopper
35
Why does adding a PI Controller and Derivative (D) reduce the spike in armature current and torque when a DC separately excited motor changes speed?
36
Draw the general response for a dc sep ex motor increasing speed through a increase in armature voltage with a PI and T-D and without a PI and T-D
37
draw and derive the torque and angular speed equations for a sep ex motor (steady state)
what can angular speed be approximated to?
Stray inductance in armature wiring and field current winding aswell
38
demonstrate an increase in armature voltage on a. torque speed graph for a sep-ex motor
39
demonstrate an increase and decrease in field current on a. torque speed graph for a sep-ex motor
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kf = 0.417
ra = 0.834
va=100v
if=1a
42
kf = 0.417
ra = 0.834
if=1a
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48
Why do photovoltaic (PV) systems primarily utilise the infrared and visible regions of the solar spectrum, and what challenges do they face in utilizing ultraviolet (UV) light?
Solar Irradiance: The total energy in the spectrum is known as solar irradiance.
PV Systems can access both the infrared and visible regions of the spectrum, making up approximately 95% of the available solar irradiance.
PV systems cant access the ultraviolet (UV) region due to the silicon bandgap (energy difference between conduction and valence bands)
49
Explain the challenge with producing universal PV systems.
The intensity of solar radiation differs depending on region
eg. Germany has lower intensity then Australia
Different sizes of panel are needed for the same power generation.
50
Explain "Full sun"
The insolation (power/m^2) at noon is highest, as sun is at highest point in the sky.
The insolation of 1000 W/M^2 is known as full sun
51
Explain "Peak Sun Hours" or "Equivalent Sun Hours"
It a way of Expressing the total energy available in a region
where 1000 W/M^2 is "Full Sun"
52
In PSH
53
What is the optimal compass direction of a PV Module in the northern and southern hemisphere
Northern Hemisphere --> Face South
Southern Hemisphere --> face North
54
calculate the energy of a photon with 500 GHZ frequency
calculate energy of a photon with a wavelength of 900nM
55
Explain the Photovoltaic Effect
56
What are the three types of material used in PV Cells, and describe the efficiency, life span and manufacture costs of each
Monocrystalline - 20+%, 25-30 Yr, High
Polycrystalline - ~16%, 25-30 Yr, Moderately High
Thin-film - up to 12%, <20 Yr, Low
57
Explain the considerations of putting PV cells in series and parallel, and series-parallel arrangements
Connecting cells to Form PV Modules
Series : Cumulative Voltage, Same Current : If one cell breaks whole panel doesn't work
Parallel: Cumulative Current, Same Voltage: if one cell breaks , it still works but low voltage.
Series-parallel: Increases in current and voltage : Compromise between both arrangements
58
What is my total voltage and current?
59
What is a PV String and a PV Array
PV String - Several modules connected in series (solar panel)
PV Array - Several PV Strings connected together.
60
Label and explain the :
Short Circuit Current
Maximum Power point
Open Circuit Voltage
Label and explain the the :
Short Circuit Current -> Connect Two terminals together (Short circuit)
Maximum Power point with a connected load
Open Circuit Voltage --> If no current was flowing (no load)
61
Draw an IV Graph demonstrating how the curve of a PV cell changes for increasing values of intensity.
Short Circuit Current is directly proportional to irradiance
62
Draw an Power-V Graph demonstrating how the curve of a PV cell changes for increasing values of intensity.
63
Draw an Power-V Graph demonstrating how the curve of a PV cell changes for increasing values of temperature
64
Draw an IV Graph demonstrating how the curve of a PV cell changes for increasing values of temperature
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What is Fill Factor
69
What is the constant Current and Constant Voltage regions of a IV curve for a PV system
Constant Current = Between (Isc,0V) to Max Power point
Constant Voltage = Between max Power point and ( 0A, Voc)
70
Express efficiency in terms of fill factor
71
Draw the one diode model of a PV Cell
72
Why does the Shunt resistance of a PV cell decrease as it ages?
Microcracks: Thermal Cycles and mechanical stresses create alternate pathways for current to flow.
Degradation of Materials: prolonged exposure to UV radiation, moisture, and temperature fluctuations
High voltage stresses can cause ion migration within the cell, leading to the formation of shunts
73
Draw the IV graph for a module with 1 cell, 2 cells in series, 2 cell sin parallel, 3 cells in series and 3 cells in parallel
74
In a PV module of 5 cells connected in series with no bypass system, one of the cells are covered.
Draw the IV graph before and after the shading effect
"Red arrows in wrong direction"
75
In a PV module of 5 cells connected in series with a bypass system, one of the cells are covered.
Draw the general System
Draw the IV graph before and after the shading effect
"Red arrows in wrong direction"
76
What are blocking diodes in PV systems
Solar panels can be damaged if its terminals are reversed. Blocking diodes prevent this
77
Why are PV systems DC.
Whys is it favourable to keep them DC
-> Voltage induced is directly proportional to light intensity. Light intensity is near constant
-> Maximum power is Peak Current * Peak Voltage. If the system was AC the power generated would be lower Prms = Peak Power / root(2)
78
Within On-grid Systems how can you improve the mismatch handling of your PV array?
Central Inverter
Array --> DC to AC Converter --> Grid
String Inverter
String --> DC to AC --> Grid
Connect every string to its own DC to AC converter
Each string is controlled to its own MPPT -> better control
Multi-String Inverter
String --> DC to DC --> DC to AC.
Each string is controlled to its own MPPT -> better control
Module Inverter
Each module is connected to a micro inverter DC-AC
Excellent Control
79
What is the fill factor of the cell?
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How many strings are in the power plant?
85
Express Equations for :
Energy in Wh
Wh
Wh in Ah.
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A PV system is used to generate ac grid energy, What equation calculates the amount of AC energy generated from the system?
88
What is the Daily Energy Requirement by the PV system?
89
What is the Total Daily Charge and Energy Requirement of the entire external system system?
90
What is the Total Daily Charge and Energy Requirement of the PV Array?
91
If the ESH of the country is 3h
What is the required current generated by the PV array
92
In the Netherlands the average annual solar irradiance is 1000 kWh/M^2
Calculate the ESH/PSH of the Netherlands
93
Design a PV Array suitable for powering the following system within a country where the PSH is 3h.
Calculate the amount of energy going to storage, and the minimum capacity of the battery required
94
You require to store 10.92 Ah of charge from a 12v system and only have 12.8V, 6Ah batteries in stock. How do you store the power?
Connect the Batteries in Parallel to get 12Ah.
Use a Buck-boost / boost converter to convert the 12v to 12.8v
95
The customer likes your design and wants you to design a system that provides 36v not 12v to this system, design a new PV array & calculate he amount of wasted energy. PSH = 3h
96
Draw a labelled power against wind speed graph for a wind turbine
97
What is:
Cut-in Speed
Rated Speed
Cut-Out Speed
Cut-in : Minimum Wind speed at which the turbine will Deliver useful power
Rated-Speed : speed at which the rated power is reached (max power output of electrical generator)
Cut-Out : Maximum wind speed the turbine is allowed to deliver power (governed by design and safety)
98
Explain what is pitch control on a turbine (aerodynamic torque control)
If the wind speed is operating above the rated speed, the pitch of the blades are adjusted to lose excess energy and keep the turbine operating at rated power.
99
What is the formula that calculate the amount of available power in the wind and amount of Extracted power
100
What is Tip speed ratio
Ratio between the tangential speed of the blades tip and the wind stream speed
Tangential Speed = : radius * angular veleocity
101
Explain the issue with MPPT on wind turbine systems
As velocity increases the optimal wind turbine speed increases.
Hence the torque of the system must be reduced to get a higher turbine speed. (speed Control
102
How is the maximum power point achieved on a wind turbine
As wind speed increase, torque of the system must be reduced to get a higher turbine speed for optimal power generation . (speed Control)
103
What happens the the frequency and Amplitude of the turbine generator signal as windspeed increases.
What are the formulas Associated
Frequency and Magnitude Increases
104
What are the two challenges with Gird Connected Wind Turbines
Rotor speed should be varying for MPPT
Generator frequency (stator speed) should be constant as the stator is connected to the grid
105
Evaluate the performance of a fixed speed Squirrel Cage induction motor as a wind turbine generator
Stator connected to grid
Grid keeps the frequency of the stator at 50Hz
No Speed Control or MPPT
106
Evaluate the performance of a Variable speed wound rotor induction motor as a wind turbine generator
Stator connected to grid
Grid keeps the frequency of the stator at 50Hz
Using the variable resistor to change the slip, which can be used to control rotor speed and achieve MPPT
Power lost within the Variable Resistor however
107
Evaluate the performance of a Variable speed synchronous generator system PMSM as a wind turbine generator
Grid connected to Ac-Dc then DC-AC system, so 50Hz is achieved from a varying frequency Fs.
Rotor speed control and MPPT is achievable
More Efficient then a Variable Resistance to Adjust Slip
108
Evaluate the performance of a Variable speed Wound Rotor "Doubly Fed" generator system as a wind turbine generator
Stator connected to grid
Grid keeps the frequency of the stator at 50Hz
Using the AC-Dc and Dc-Ac inverters to adjust the rotor current frequency to change the slip, which can be used to control rotor speed and achieve MPPT
Difficult to Control
More efficient then Wound Rotor systems (variable resistor)
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What led to the success of ICE vs BEV's in the late 1800s & early 1900s.
What advantage do BEV's hold?
The Specific Energy Density of Petrol and such fossil fuels is much large then batteries (9000 wh/kg vs 30 wh/kg)
(Battery to fuel tank ratio = 30)
A Much higher efficiency vs ICE's
(90% vs 20% )
111
Sketch the Optimum Characteristic Curve for a Car.
Use it to explain why a BEV provide better acceleration.
Armature control using a Sep-Ex DC motor provides the same curve.
112
Draw the typical characteristic curve for an ICE engine (No Gears)
113
Draw the typical characteristic curve for an ICE car (with Gears)
114
Explain why an ICE car requires gears but an BEV doesnt to achieve the same performance.
BEV's characteristic curve is much closer to the optimum (dark green), we use a gear box to try and mimic the ideal curve as close as possible.
115
How do you calculate the gear ratio for a gearbox?
116
Draw the typical characteristic curve for an BEV
117
What is a BEV architecture, draw a block diagram for it.
Battery: Stores electrical energy to power the system.
Charger: Replenishes the battery with external electrical energy.
Motor Driver (Power Converter): Regulates energy from the battery to drive the motor efficiently.
MC (Motor Coupling): Connects the motor to the transmission to transfer mechanical energy
.
Electric Motor: Converts electrical energy into mechanical motion.
Trans (Transmission): Transfers motor-generated mechanical energy to the wheels for efficient motion.
Wheels: Propel the vehicle by converting mechanical energy into movement.
118
What is a series PHEV architecture, draw the block diagram
Battery: Supplies electrical energy to power the motor driver and the wheels.
Charger: Replenishes the battery with external electrical energy.
Motor Driver (Power Converter): Regulates energy from the battery to drive the motor efficiently.
MC (Motor Coupling): Connects the motor to the transmission to transfer mechanical energy.
Electric Motor (EM): Propels the vehicle by converting electrical energy into mechanical motion.
Fuel: Provides energy for the internal combustion engine (ICE).
Internal Combustion Engine (ICE): Converts fuel into mechanical energy to charge the battery.
Generator (Gen.): Converts mechanical energy from the ICE into electrical energy for the battery.
Transmission (Trans.): Transfers mechanical energy to the wheels efficiently.
Wheels: Propel the vehicle by converting mechanical energy into movement.
119
What is a parallel PHEV architecture, draw the block diagram
Battery: Supplies electrical energy to power the motor driver and electric motor.
Charger: Replenishes the battery with external electrical energy.
Motor Driver (Power Converter): Regulates energy from the battery to drive the motor efficiently.
Electric Motor (EM): Contributes tractive power to propel the vehicle alongside the ICE.
Fuel: Provides energy for the internal combustion engine (ICE).
Internal Combustion Engine (ICE): Supplies mechanical power directly to the transmission for propulsion and tractive effort.
MC (Motor Coupling): Connects and integrates the mechanical output of the ICE and EM to the transmission.
Transmission (Trans): Transfers combined mechanical energy from the ICE and EM to the wheels.
Wheels: Propel the vehicle by converting mechanical energy into motion.
120
What is a series-parallel PHEV architecture, draw the block diagram
Battery: Supplies electrical energy to power the motor driver and the system.
Charger: Replenishes the battery with external electrical energy.
Motor Driver (Power Converter): Regulates energy from the battery to drive the motor efficiently.
Electric Motor (EM): Converts electrical energy into mechanical motion to propel the vehicle.
Fuel: Provides energy for the internal combustion engine (ICE).
Internal Combustion Engine (ICE): Converts fuel into mechanical energy to assist propulsion or charge the battery.
Generator (Gen.): Converts mechanical energy from the ICE into electrical energy for battery charging.
MC (Motor Coupling): Uses planetary gears to mechanically connect the ICE, EM, and Gen. for efficient power distribution.
Transmission (Trans.): Transfers mechanical energy to the wheels in both series and parallel configurations.
Wheels: Propel the vehicle by converting mechanical energy into motion.
121
Draw the following charger configurations
Off-Board
On-Board
On-Board Integrated charger (M-Motor and F-Filter)
122
What are the Advantages and Limitations of On-Board and Off-Board Chargers
On-Board
+ Can charge from AC supply anywhere
- Has to be small enough to fit in car-> charging power is limited
Off-Board
+ Can have a large charging power as Filter and converter can be larger as it doesn't need to be in the vehicle.
- More infrastructure required to use
123
What is an On-Board Integrated Charger?
Same converter is used in Charging the car, and powering the motor
124
What is the main disadvantage of DC motors?
How does that affect the maintained of a DC motor?
-> Terminals need to switch polarity periodically (every 1/2 cycle) (require and ac signal)
--> Done using carbon brushes and a slip ring commutator
Carbon brushes will need to be replaced ~ every 6 months
125
define a battery
What is the formula for determining the terminal voltage of a battery?
two or more cells connected in series
126
What is Ah and Wh
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128
Determine the nominal time for a current of 4.2 A to be drawn from this battery
129
What is specific energy?
What is energy density
amount of electrical energy store for every kilogram of battery mass (Wh/kg)
amount of electrical energy stored per meter cubed of battery volume (Wh/m^{3})
130
what occurs when a BEV's charge goes below 20%
Efficiency drops off massively from a greater amount of stress
131
draw an approximate sketch of the graph of the voltage supplied against capacity /mAh of nominal current C , 3C and 6C and comment on the change
At higher nominal currents the voltage supplied drops, which decreases the efficiency as the drawn Ah has not changed
132
Define the Following Terms:
Depth of Discharge
State of Charge
DOD : A value between 0-1 , where 0 is fully charged and 1 is empty
SOC : A value between 1-0 , where 1 is fully charged and 0 is empty
133
This is the formula for the Open-Circuit Voltage E of a Lead Acid Battery
What do each of the terms mean?
Plot the graph of Voltage against DOD
n = number of cells in series
DOD - depth of discharge
134
Why is battery modelling required.
-> Drawing different amounts of current charges the Open circuit voltage E and the Efficiency of the battery
-> the battery's efficiency changes as DOD and SOC changes
Hence a model is required to predict :
DOD
Open Circuit Voltage E
Power
135
A battery is quoted to have a nominal capacity of 42Ah at a 10h rate with a Peukert coefficent of 1.1
Using the peukert model, predict the effective capacitance in the following situations:
-20 A of discharge Current
-Battery Fully Discharges in 6h
136
Explain the Peukert Model
Evaluate the performance of the model
Used when Battery Fully Discharges
-> ~95% accurate
-> not very accurate at low currents,
-> high currents model performs well enough
-> doesn't consider temperature at all
-> battery aging isn't considered (but you can recalculate the value of K)
-> Self Discharge isnt considered (discharged if left unused)
137
What change is made to the peukert model when your battery doesn't fully discharge
138
Derive a formula to predict the current drawn by a battery for an electric motor of Open voltage E
139
How do you determine the Peukert Coeffiicient?
What happens to the Peukert coefficient over time
It increases
140
Determine the Peukert Coefficent
141
Define Traction
Draw a Free body diagram of a car going up a slope
Force propelling the car forward, reaction force of the drive wheels pushing agaisnt the ground
142
Define Rolling Resistance, what is the equation?
Resistive force acting against the motion of the car. from Tyre Deformation and Friction of the vehicle tyre on the road
-> usually constant
143
Define Aerodynamic Drag, what is the equation?
Friction of the vehicle body moving through the air
144
Define Hill Climbing force, what is the equation?
Component of the vehicles weight acting along the slope, agaisnt the direction of motion.
145
Define Acceleration Force , what is the equation?
The non zero resultant force of the vehicle when it is not at a constant speed
146
Show how
147
show how the ratio of the force providing the angular acceleration at the wheels to the linear acceleration of a wheels can be approximated to 0.05
Write the Equation expressing the tractive effort of a car.
148
Determine the Max Angular velocity of the wheels, acceleration of the wheels and torque applied to the wheels.
Assume no resistances to motion
149
Determine the Max Angular velocity of the motor and torque applied to the motor.
Assume no resistive forces
150
Determine the total resistive forces due to friction acting on the vehicle
151
Calculate the travel time and distance for the following vehicle under the assumptions :
Vehicle always travels at its constant top speed
A constant force is applied to the wheels from beginning to end
100% efficiency of battery (DOD), controller/generator and transmission
152
Assuming the following Vehicle has 100% efficient Regenerative braking, find the Total Energy dissipated by the car
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(lead acid battery)
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What is an Actuator? , Name 4 Common types of Actuators
a device that converts energy into motion
156
Fill in the table about Asynchronous and synchronous AC motors
157
Fill out the table about Brushed and Brushless DC Motors
158
Fill out the table about types of AC Motors
159
What is a servo motor?
How do you control a servo?
A motor that contains its internal feedback (motor + sensor) , closed loop system, very good precision
Width of the PWM pulse of the control signal going into the servo (usually 20ms period)
160
Draw a block diagram of a Variable Speed Frequency drive controlled Device
Name benefits to VSD
-> ac motor
-> VSD controls voltage and frequency of signal to control
VSD-> power converter (rectifier+inverter) and controller
--> feedback speed signal is sent back to VSD to close the loop.
Improves efficiency and provides a full range of control
161
Draw the Torque-Speed Curve for a :
Sep Ex DC motor
Induction Motor
Synchronous Motor
Constant Load
Linear Load
Quadratic Load
162
How would you move the operating point of the load curve from p1 to p2
Using a VSD (ac motor)
Decrease frequency of signal
To ensure the peak torque stays constant
Constant V/f ratio
163
four quadrant control is used to control the VSD of a car, which colours of the curve go to each quadrant?
164
What is an incremental-drive "digital" motor?
Describe briefly how it works
In a soft iron stepper motor if the phases are activated anti-clockwise in the stator which way will the rotor spin
In a permanent magnet stepper motor if the phases are activated anti-clockwise in the stator which way will the rotor spin
Type of actuator that rotates in steps
Rotor teeth move in steps according to magnetic flux orientation
The polarity of the windings change which generates a changing magnetic flux
Clockwise
anticlockwise
165
in a stepper motor the rotor will always move to the position where the magnetic forces are balanced know as the _________________________________
What is full-stepping and half-stepping
point of minimum reluctance
- Full-Stepping: The motor moves in full steps, with one phase active at a time. Provides maximum torque but lower resolution.
-Half-Stepping: The motor alternates between full steps and intermediate steps, with both phases active at once. Increases precision but slightly reduces torque.
166
fill the table evaluating the different types of stepper rotor material
167
On a stepper motor, draw a diagram and provide a formula to calculate:
Stator Angle
Rotor Angle
What condition has to be considered when choosing rotor and stator angles for a stepper motor?
The rotor angle can't be the same as the stator angle in a stepper motor because they depend on different numbers of poles
168
how do you calculate the step/stepping angle of a stepper motor
169
calculate the step angle of the following stepper motor cross section.
170
Draw the Torque speed graph of a stepper motor
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