electrical power drivers et3026 wb lecture 9-13
TRANSCRIPT
March 22, 2009
1
Elektrische Aandrijvingen WTB
Lokatie/evenement
P.BAUER
March 22, 2009 2
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Figure 21.1 Potential level method of representing voltages. Figure 21.2 Potential levels of terminals 1, 2, and 3.
Fundamental Elements of Power Electronics
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Figure 21.3 Changing the reference terminal. Figure 21.4 The relative potential levels are the same as in Fig. 21.2.
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Voltage across some circuit elements
Figure 21.5 Potential across a switch. Figure 21.6 Potential across a resistor.
Figure 21.7 Potential across an inductor. Figure 21.8 Potential across a capacitor.
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Figure 21.9 Basic rules governing diode behavior. Diode
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Figure 21.10 (continued) a. Average current: 4 A; PIV: 400 V; body length: 10 mm; diameter: 5.6 mm. b. Average current: 15 A; PIV: 500 V; stutype; length less thread: 25 mm; diameter: 17 mm. c. Average current: 500 A; PIV: 2000 V; length less thread: 244 mm; diameter: 40 mm. d. Average current: 2600 A; PIV: 2500 V; Hockey Puk; distance between pole-faces: 35 mm; diameter: 98 mm. (Photos courtesy of InternationaRectifier)
Figure 21.10 (continued) a. Average current: 4 A; PIV: 400 V; body length: 10 mm; diameter: 5.6 mm. b. Average current: 15 A; PIV: 500 V; stud type; length less thread: 25 mm; diameter: 17 mm. c. Average current: 500 A; PIV: 2000 V; length less thread: 244 mm; diameter: 40 mm. d. Average current: 2600 A; PIV: 2500 V; Hockey Puk; distance between pole-faces: 35 mm; diameter: 98 mm. (Photos courtesy of International Rectifier)
Figure 21.10 (continued) a. Average current: 4 A; PIV: 400 V; body length: 10 mm; diameter: 5.6 mm. b. Average current: 15 A; PIV: 500 V; stud type; length less thread: 25 mm; diameter: 17 mm. c. Average current: 500 A; PIV: 2000 V; lengt h less thread: 244 mm; diameter: 40 mm. d. Average current: 2600 A; PIV: 2500 V; Hockey Puk; distance between pole-faces: 35 mm; diameter: 98 mm. (Photos courtesy of International Rectifier)
Figure 21.10 a. Average current: 4 A; PIV: 400 V; body length: 10 mm; diameter: 5.6 mm. b. Average current: 15 A; PIV: 500 V; stud type; length less thread: 25 mm; diameter: 17 mm. c. Average current: 500 A; PIV: 2000 V; length less thread: 244 mm; diameter: 40 mm. d. Average current: 2600 A; PIV: 2500 V; Hockey Puk; distance between pole-faces: 35 mm; diameter: 98 mm. (Photos courtesy of International Rectifier)
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Figure 21.11 a. Simple battery charger circuit. b. Corresponding voltage and current waveforms.
Figure 21.11 (continued) a. Simple battery charger circuit. b. Corresponding voltage and current waveforms.
Battery charger with resistor
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Battery charger with inductor
Figure 21.12 a. Battery charger using a series inductor. b. Corresponding voltage and current waveforms.
Figure 21.12 (continued) a. Battery charger using a series inductor. BCorresponding voltage and current waveforms.
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Figure 21.12c See Example 21-1.
Example 21.1
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Figure 21.13a a. Single-phase bridgerectifier. b. Voltage levels.
Figure 21.13b a. Single-phase bridge rectifier. b. Voltage levels.
Single bridge diode rectifier
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Figure 21.13c Voltage and current waveforms in load R.
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Figure 21.14 a. Rectifier with inductive filter. b. Rectifier with capacitive filter.
Figure 21.15 Current and voltage waveforms with inductive filter.
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Figure 21.18 Dual 3-phase, 3-pulse rectifier.
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Figure 21.19 Three-phase, 6-pulse rectifier with inductive filter.
Three-phase 6 pulse rectifierFigure 21.20 Voltage and current waveforms in Fig. 21.19.
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Figure 21.21 Another way of showing EKA using line voltage potentials. Note also the position of E2N with respect to the line voltages.
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Figure 21.22 Successive diode connections between the 3-phase input and dc output terminals of a 3-phase, 6-pulse rectifier.
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Figure 21.23 Line-to-neutral voltage and line current in phase 2 of Fig. 21.20.
Effective, fundamental line current
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Figure 21.24 Symbol of a thyristor, or SCR.
The thyristor
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Figure 21.25 a. A thyristor does not conduct when the gate is connected to the cathode. b. A thyristor conducts when the anode is positive and a current pulse is injected into the gate.
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Figure 21.26 Range of SCRs from medium to very high power capacity.
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Figure 21.27 a. Thyristor and resistor connected to an ac source. B. Thyristor behavior depends on the timing of the gate pulses.
Figure 21.27 (continued) a. Thyristor and resistor connected to an ac source. b. Thyristor behavior depends on the timing of the gate pulses.
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Figure 21.28 a. Thyristor connected to a dc source. b. Forced commutation.
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Figure 21.29 A discharging capacitor C and an auxiliary thyristor Q2 can force-commutate the main thyristor Q1. Thus, the current in load R can be switched on and off by triggering Q1 and Q2 in succession.
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Figure 21.30 a. SCR supplying a passive load. b. Voltage and current waveforms.
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Figure 21.31 a. SCR supplying an active load. b. Voltage and current waveforms.
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Figure 21.32 a. Line-commutated inverter. b. Voltage and current waveforms.
Line commutated inverter
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Figure 21.33 a. Electronic contactor. b. Waveforms with a resistive load.
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Figure 21.34 Elementary cycloconverter.
Cycloconverter
Figure 21.35 Typical voltage output of a cycloconverter.
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Figure 21.36 Three-phase, 6-pulse thyristor converter.
3 phase 6 pulse contr.converter
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Figure 21.40a Delay angle: zero.
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Figure 21.40b Delay angle: 15°.
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Figure 21.40c Delay angle: 45°.
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Figure 21.40d Delay angle: 75°.
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• The 3 phase converter is connected to 3 phase 480 V 60 Hz source, Load 500 V dc resistance 2 ohm. Calculate the power supplied to the load for delays of 15 and 75.
Example 21.17
• Ed = 1,35 E cos ά
voltage drop on R• E= Ed - Eo
• Id = E/R
• P = EdId
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Figure 21.41 Three-phase, 6-pulse converter in the inverter mode.
Inverter mode
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Figure 21.42a Triggering sequence and waveforms with a delay angle of 105°.
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Figure 21.42b Triggering sequence and waveforms with a delay angle of 135°.
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Figure 21.42c Triggering sequence and waveforms with a delay angle of 165°.
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Figure 21.43 Permitted gate firing zones for thyristor Q1.
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Figure 21.44 Equivalent circuit of a thyristor converter.
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Figure 21.45 Equivalent circuit of a 3-phase converter in the rectifier mode.
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Figure 21.46 Equivalent circuit of a 3-phase thyristor converter in the inverter mode.
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Figure 21.47 Voltage and current waveforms in the thyristor converter of Fig. 21.39 with a delay angle of 45°.
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Figure 21.48 See Example 21-11.
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Figure 21.49 a. Instantaneous commutation in a rectifier when ∝ = 45° (see Fig. 21.58). b. Same conditions with commutation overlap of 30°, showing current waveshapes in Q1, Q3, Q5.
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Figure 21.49 (continued) a. Instantaneous commutation in a rectifier when ∝ = 45° (see Fig. 21.58). b. Same conditions with commutation overlap of 30°, showing current waveshapes in Q1, Q3, Q5.
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Figure 21.50 Waveshape of i1 in thyristor Q1 for a delay angle ∝. The extinction angle γ permits Q1 to establish its blocking ability before the critical angle of 300° is reached. At 300° the anode of Q1 becomes positive with respect to its cathode. The figure also shows the relationship between angles ∝, β, γ, and u.
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Figure 21.51 Typical properties and approximate limits of GTOs and thyristors in the on and off states.
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Figure 21.54 Typical properties and approximate limits of IGBTs.
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Figure 21.59 E and I in the inductor of Fig. 21.58.
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Figure 21.60a Currents in a chopper circuit.
• Io = (Ia + Ib)/2 • IS = Io (Ta/T) • IS = Io D
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Figure 21.60b Current in the load.
• EsIs = EoIo
• Eo=EsIs/Io
• Eo= D Es
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Figure 21.60c Current pulses provided by the source.
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Example 21-11Charge 120 V battery from 600 V dc source using a dc chopper, average current 20 App ripple 2 A, f =200Hz• dc current from the source• dc current in the diode• the duty cycle• inductance of the inductor
• P = EoIo
• Is = P/ Es
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Example 21-11Charge 120 V battery from 600 V dc source using a dc chopper, average current 20 App ripple 2 A, f =200Hz• dc current from the source• dc current in the diode• the duty cycle• inductance of the inductor
• ID = Io- Is
• D = Eo/ Es
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Example 21-11Charge 120 V battery from 600 V dc source using a dc chopper, average current 20 App ripple 2 A, f =200Hz• dc current from the source• dc current in the diode• the duty cycle• inductance of the inductor
• ID = Io- Is
• D = Eo/ Es
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2 quadrant DC-DC converter
• EL=D EH
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Figure 21.64 Power can flow from EH to EO and vice versa.
• IL = (EL- Eo)/ R
EL > Eo
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Figure 21.65 Circuit of Example 21-13.
EL < Eo
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Example 21-13.
100 V, 30 V, S ohm, 10 mH, 20 kHz, D=0,2
Value and direction of ILPp ripple
• EL = D EH= 20V
• IL = (Eo- EL)/ R
• T = 1/f
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Figure 21.66 See Example 21-13.
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Figure 21.67 See Example 21-13.
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Figure 21.69 Two-quadrant electronic converter.
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Figure 21.70 Four-quadrant dc-to-dc converter.
• EL = D EH= 20V
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Figure 21.70 Four-quadrant dc-to-dc converter.
• ELL = EH (2D-1)
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Figure 21.73 Four-quadrant dc-to-dc converter feeding a passive dc load R.
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Figure 21.74 Four-quadrant dc-to-dc converter feeding an active dc source/sink Eo.
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Figure 21.75a Switching semiconductor and snubber.
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Figure 21.76a The square wave contains a fundamental sinusiodal component.
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Figure 21.76b Single-phase dc-to-ac switching converter in which D = 0.5 and f can be varied.
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Figure 21.77 Four-quadrant dc-to-ac switching converter using carrier frequency fc and three fixed values of D.
• ELL = EH (2D-1)
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Figure 21.78 Frequency and amplitude control by varying D.
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Figure 21.79 Frequency, amplitude, and phase control by varying D.
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Figure 21.80 Waveshape control by varying D.
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Dc-AC SINE WAVE CONVERTER
• ELL = EH (2D-1)
• EH given
• ELL requested f(t)
• E = Em sin (360ft+ θ)
• D(t) = 0.5 [1+Em/EH sin (360ft+ θ)]
• amplitude modulation ratio
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Example 21-14
• 200V dc source 4 q, switching converter operating at the carrier of 8kHz, desired sinusoidal 120 V 97Hz and θ=35
• Em = 120 Sqrt(2) = 170 V
• m= Em / EH = 170/200 =0,85
• mf= fc / f= 8000/97 =82,47
• D(t) = 0.5 [1+Em/EH sin (360ft+ θ)]
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Figure 21.82 Positive half-cycle of the fundamental 83.33 Hz voltage comprises six carrier periods of 1 ms each.
• D(t) = 0.5 [1+Em/EH)
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Figure 21.85 A two-quadrant PWM chopper and its load. The filter eliminates the unwanted carrier frequency component.
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Figure 21.87 A comparator determines the crossing points between the miniature version ES of the wanted waveshape EL(t) and a triangular waveshape, thereby producing the control signal D(t). The signal triggers the switches in the chopper to generate the PWM waveshape that contains the wanted output EL(t). .
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DC-AC 3 phase converter
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Figure 21.91 a. PWM pulses between terminals A and Y, and their sinusoidal EAY component. b. PWM pulses between terminals B and Y, and their sinusoidal EBY component.
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Figure 21.91 a. PWM pulses between terminals A and Y, and their sinusoidal EAY component. b. PWM pulses between terminals B and Y, and their sinusoidal EBY component.
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Figure 21.93 Block diagram of a 3-phase PWM converter.
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Example 21.15
•3 phase 245 V 60 Hz wanted, dc = 500 V , fc=540 Hz
• the peak value of fundamental voltage•L1 N
• ELN = 245/ sqrt(3)= 141 V
• Em = ELN sqrt (2) = 200 V
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Figure 21.95 See Example 21-15.
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Figure 21.94 A more detailed diagram of a 3-phase PWM converter using IGBTs and a 3-phase RLC filter to suppress the carrier frequency components. The capacitors across the dc side provide a path for the reactive currents that are drawn by the 3-phase load.
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Figure 21.97 Three-phase PWM voltages produced by a dc-to-ac converter operating at a carrier frequency of 540 Hz with a 500 V dc input. Top: EAY, EBY, ECY outputs, peak sinusoidal component = 200 V. Bottom: EAB, EBC, ECA outputs, peak 60 Hz sinusoidal component = 346 V, RMS value = 245 V.
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Energy management
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Variable voltage system
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Series hybrid drivetrain
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Parallel hybrid drivetrain
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Energy storage
can be classified as• Mechanical Energy Storage. • Magnetic Energy Storage. • Thermal Energy Storage. • Chemical Energy Storage.
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Energy storage device
Fundamental properties• the energy that can be stored in the element;• the power that can be drawn from/charged in the
storage element;• the specific energy (energy per unit weight);• the specific power (power per unit weight);• the energy density (energy per unit volume);• the power density (power per unit volume).
March 22, 2009 98
Energy storage device
Technology and economy• cycle life;• self-discharge;• costs • fast charge time;• cell voltage;• load current;• maintenance requirement;• energy efficiency.
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Mechanical Energy Storage: Fly Wheels
• Principle: Energy is stored in the form of Mechanical Energy.
• Light weight fiber composite materials are used to increase efficiency.
• Energy density=0.05MJ/Kg, η=0.8
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•The Energy Density is defined as the Energy per unit mass:
•Where,
V is the circular velocity of the flywheel σ is the specific strength of a material ρ is the density of the material
•
2E 1 Vm 2
σ= =
ρ
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Properties of some materials used for building flywheels.
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Advantages and disadvantages:
• Very compact when compared to other energy storage systems.
• Flywheels are used for starting and braking locomotives.
• A flywheel is preferred due to light weight and high energy capacity.
• It is not economical as it had a limited amount of charge/discharge cycle.
March 22, 2009 104
Batteries
• the lead-acid battery, nickel cadmium battery (NiCd), the nickel metal hydride battery (NiMH) and the Lithium ion battery (Li-ion).
iR
0E
ohmR
20
peak,storageint ohm4( )EP
R R=
+
peak,storagepeak,storage/gram
PP
m=
March 22, 2009 105
Battery model
March 22, 2009 106
Comparison of prices
0
500
1000
1500
2000
2500
VRLA[A]
Lead -acid [B]
NiCd [B] NiMH[A]
NiMH[B]
Li-ionHE [A]
Li-ionHP [C]
Pric
e [$
/kW
h]
Low High
March 22, 2009 107
Supercapacitor
sR
C culR
2
peak,storages4( )
cuPR
=
21C2E Cu=
March 22, 2009 108---------------7
0-91,33
6 [17]-750-
1200+
-200-300
70-95
-
-low environmental impact
-moderate
--20 to 40
----------65-70
Moderate
10800-1200
33
200-600
-40-80
-
flat-----20 to 50
--moderate to high
--1,01,25-1,10
1,4
1,2--15-2534
35
2-5300-6002
6 33
--753524035
-relatively low toxicity but should
be recycled
thermally stable,
fuse recommended
60 to 90 days
low-20 to 6032
2 to 4
200 to
3003
0 40
-≤0,5
5---1,2539
--3028
38-300
to 5002
6 27 37
--60-120
-Ni
MH
---------------75
-15,23
6-800-80-
15050-60
-
very flat
-----40 to 45
--moderate to high
--1,01,25-1,00
1,29
1,2--15-2034
35
2-5300-7002
6 33
--353510035
Sealed
very flat
-----40 to 50
--high--1,01,25-1,00
1,29
1,2--1034
353-10500-
200026 33
--30-3735
58-963
5
Vented
Sintered plate
flat-----20 to 45
--high--1,01,25-1,00
1,29
1,2--534 358-25500-2000 26 33
--2035403
5Vente
d Pocket plate
-Highly toxic, environmentally
unfriendly
thermally stable,
fuse recommended
30 to 60 days
moderate
-40 to 6032
1[16
]100-2003
0 [15]
-120
---1,25[14
]
--2028
[13]-1500
27
[12]
--45-80
-NiCd
---------------> 80
-9,1[11
]-500-
1000-150-
40035-50
-
-high environmental
impact
-1 check/y
ear
-10 to 30
----------75-95
Very low
5100033
50-100
-10-20
-VRLA
flat-----20 to 40
--moderately
high
--1,75
2,0-
1,8
2,1
2,0--4-6[9]
[10]61500
26 [8]--2535803
5Tracti
on
-lead and acids environmentally
unfriendly
thermally stable
3 to 6 months
high-20 to 60[7]
8 to 16
< 100[
5] [6]
-0,2
5[4
]
---2--5[3]-200-300[
1] [2]
37
--30-50
-SealedLead-acid
Best Result
Peak
End of Life
Operating
Open Circuit
Nominal
Overall
Charging
continuous
peak
Discharg
e-profile
(relatively)
ToxicitySafetyMaintenance Requirement
Overcharge Tolerance
Operating
Temperature [°C]
Fast
Charge Time [h]
Internal Resistance
[mΩ]
Power
Density
Load Current
[C]
Cell Voltage [V]Efficiency [%]
Self-discharge [%/
month]
Calendar life [years]
Cycle life
Specific Power [W/kg]
Specific Energy [Wh/kg]
Energy
Density [Wh/l]
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-low environmental impact
-no--25 to 65
----------85 –95
Low> 10> 500.000
500 –
2000
-1 –3
-Super capacitor
????????????????????????HP (info epyon)
-lowprotection
circuit recommended;
stable to 150 °C
not require
d
low, no
trickle charge
-20 to 6032
≤ 125-5030
46
-≤10
>
30
---3,3--1028
45->
1000 27 [5]
--90-120
-HP (phosphate)
-lowprotection
circuit recommended;
stable to 250 °C
not require
d
low, no
trickle charge
-20 to 6032
≤ 125-7530
[4]
-≤10
>
30
---3,643
--1028
[3]-bette
r than 300-5002
6 27
--100-135
-HP (manganese)
---------------> 95
-10,63
6-≥
1000-200-
30080-130
-HE
-low environmental impact
-moderate
--20 to 45
----------90-95
Moderate
10> 1000
33
200-1000
-60-100
-HE
sloping
-----20 to 50
--moderate;
high in
prismati
c designs
--3,0
4,0-3,0
4,1
4,0--234 35->100026
33
--1503
540035
HE (cobalt)
-lowprotection
circuit required; stable to 150
°C
not require
d
low, no
trickle charge
-20 to 6032
1,5 to 3
150-3003
0 [2]
-≤1
<
3
---3,6[
1]--1028
45 -300-
5002
6 27
--HE (cobalt)
Li-ion
Best Result
Peak
End of Life
Operating
Open Circuit
Nominal
Overall
Charging
continuous
peak
Discharg
e-profile
(relatively)
ToxicitySafetyMaintenance Requirement
Overcharge Tolerance
Operating
Temperature [°C]
Fast
Charge Time [h]
Internal Resistance
[mΩ]
Power
Density
Load Current
[C]
Cell Voltage [V]Efficiency [%]
Self-discharge [%/
month]
Calendar life [years]
Cycle life
Specific Power [W/kg]
Specific Energy [Wh/kg]
Energy
Density [Wh/l]
rage voltage under load is 3,7 V, so higher than the nominal voltage. The battery is often rated to this average voltage. pack.internal protection circuit uses 3 % of the stored energy per month.cell.conditions.
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Case study
Stand alone systems with diesel generator and 4Q operation
(crane, elevator, car)• Size of the energy storage and generator (cost)• Power Management Strategy (PMS)• voltage level and interface with power
electronic converter
March 22, 2009 111
Hybrid Dynamic Systems with Energy Storage
Stand alone systems with diesel generator and 4Q operation
(crane, elevator, car)• Size of the energy storage and generator (cost)• Power Management Strategy• voltage level and interface with power
electronic converter
Fig. 3. System topology for generator with Super capacitor.
Fig. 2. System topology for generator with Li-ion HP battery.
Fig. 1. Overview of generator with energy storage for 4Q-load.
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Load profile
1. hoisting the empty spreader;2. moving the trolley without load;3. moving the crane;4. lowering the spreader without load;5. hoisting a container;6. moving the trolley with a container;7. moving the crane with a container;8. lowering the container.
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Simplified power profile
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Only Generator
• Max 1 pu, average power 0,14 pu• Breaking resistor
PB1PB2
Dia 114
PB1 The first part of the graph shows the elevator accelerating to travel up, travels up for a while at constant speed and decelerates. In the second part of the graph the elevator accelerates to travel down, travels down for a while at constant speed, and decelerates. There is a need for a large peak power for a short period during acceleration, and that during deceleration the system supplies small peak energy back during a short period.P Bauer; 28-5-2008
PB2 the power is fully being supplied by a generator. This system shows no difference with the normal case and is used as a reference.
The nominal peak power of the generator is P Bauer; 27-5-2008
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Only Generator
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Peak power shaving
• Generator Max power 0,78 pu, 0,021 pu stored
PB3
Dia 116
PB3 When the Peak Power Shaving PMS is used, the generator supplies most of the power. The storage element only supplies the power peaks needed for a short period of time. Parts of more or less constant power are supplied by the generator.T he storage element will be small. Not all regenerated energy can be stored in the storage element because of this small size.The nominal peak power of the generator is 0,78 . The energy that should be stored in the storage element is P Bauer; 27-5-2008
March 22, 2009 117
Peak power shaving
March 22, 2009 118
Dynamic Power ManagementPB4
Dia 118
PB4 The Dynamic Solution PMS (DS) is specially designed for use with a VSCF generator. Such a generator cannot react to changes in the output power instantaneously. The energy storage is used to supply/absorb the difference in needed power and power from the generator.P Bauer; 27-5-2008
March 22, 2009 119
Dynamic Power Management
March 22, 2009 120
Average power
• Generator Max 0,14 pu
PB5
Dia 120
PB5 In the Average Power PMS (AV), the generator continuously supplies the average power needed. All variations on this average power will be supplied or absorbed by the energy storage. P Bauer; 27-5-2008
March 22, 2009 121
Average power
March 22, 2009 122
Max On or Off Power Management
• Generator Max 0,33 pu
PB6
PB7
Dia 122
PB6 In the Max On or Off PMS (MOO), the generator supplies its maximum rated power or it is turned off. The generator is dimensioned in such a way that its power rating is higher than the average power neededP Bauer; 27-5-2008
PB7 P Bauer; 28-5-2008
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Max On or Off Power Management
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Only storage PB8
PB9
Dia 124
PB8 The Only Storage PSM (OS) supplies only power from an energy storage device. The storage can be charged from the grid. Electricity from the grid is less expensive than electricity generated by a diesel generator (comparing [10] and [11]). Further unbalanced cycles becomes an option.P Bauer; 27-5-2008
PB9 The energy storage becomes never empty. But after one cycle the storage element contains less energy. The decrease in energy is: . The fact that the energy in the energy storage decreases makes this system, for this case study, not feasible as stand alone system.P Bauer; 27-5-2008
March 22, 2009 125
Only storage
March 22, 2009 126
Figures of merit
• energy recovery factor
• dissipation factor
recovered
regenerated
ERECE
=
dissipated
regenerated
EDIS
E=
PB10
PB11
Dia 126
PB10 The energy recovery factor is the ratio between the total amount of energy that is recovered from the load and stored in the storage element ( ), and the total energy that could be recovered from the load (P Bauer; 27-5-2008
PB11 If , the dissipated and recovered energy is only the energy that could be recovered from the load. If, , energy is dissipated that comes straight from the generator. This is a disadvantageous situation.P Bauer; 28-5-2008
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Energy recovery
March 22, 2009 128
Li-ion HP1 1overSize
EOL DOD= ⋅cycle (DOD, EOL)f x= =
PB12
Dia 128
PB12 The lifetime of a Li-ion HP battery is depended on the depth of discharge (DOD), number of cycles and the age [4]. The dependency on the DOD is not linear, a lower DOD means a much larger cycle life [4]. This relation is given schematically in Fig. 14. The lifetime of a Li-ion batteryis 10 year [4, 13].P Bauer; 28-5-2008
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Sizes of the generator and storagePB13PB14
PB15
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PB13 From energy saving point of view an optimum can be found. This is the line where all regenerated energy can be stored in the energy storage. This is given with the horizontal line in P Bauer; 28-5-2008
PB14 For the lifetime for the Li-ion HP battery it was calculated in section V that the energy storage should be oversized with a factor 42,8 to get the optimal cycle life. This optimal cycle life is given by the dashed line in (Fig. 15a).P Bauer; 28-5-2008
PB15 Combining the optimal lines of (Fig. 15a) and (Fig. 15b) result in (Fig. 15c). The line for the optimal energy saving should be multiplied with thefactor 42,8. The intersection of the obtained line and the optimal cycle life line gives an optimum. In the figure an illustration is given for the PMSs. The intersection found in (Fig. 15c) of the optimal cycle life line and the optimal energy line gives a theoretical technical optimum. P Bauer; 28-5-2008
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Comparison for costs for the different PMSs
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Data for cost calculation
3 punom,gen,peak59 10 4676 [€]P⋅ ⋅ +
[22]43 %Fuel efficiency generator
[21]35.700 [kJ/l]Caloric value diesel
[7]75 [€/kW]Price power electronics
[20]Price generator
[13]45.000 [€/kWh]Price super capacitor
[4]2.000 [€/kWh]Price Li-ion HP
[10]0,10 [€/kWh]Price electricity
[11]1,00 [€/l]Price fuel
SourceDataParameter
3 punom,gen,peak59 10 4676 [€]P⋅ ⋅ +
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Sensitivity study: Variable Fuel Prices
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Sensitivity study: Variable Li-ion Prices
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Sensitivity study: Variable Generator Prices
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Sensitivity study: Variable Power Electronics Price
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Experimental verification Max On Off
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Conclusions
• Six different pms are defined• Fuel prices and storage prices are the most sensitive
element• After an increase of 40%of fuel prices and 25%
decrease of Li-ionprices the Max On or Off method has an advantage over the dynamic solution