EEL 4242 POWER ELECTRONICS

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EEL 4242POWER ELECTRONICS

• DC-DC CONVERTERS

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Step Down Converter
Figure 5.1

• Constant frequency operation
• Variable frequency operation

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PWM Waveform Generation
Figure 5.2

• which is also called the modulation voltage, M
  

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Step Down Operation with RL Load
Figure 5.3
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Step Down Operation with RL Load
Figure 5.4
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Modes of Operation
Figure 5.4
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Modes of Operation
Figure 5.4
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Discontinuous Operation

• For a continuous load current

Figure 5.4
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Step-Up Operation

• The average output voltage

Figure 5.6
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Step-Up Operation

• For controllable power

Figure 5.7
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Step-Up Operation
Figure 5.8
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Converter Classifications

• 1st Quadrant converter
• 2nd Quadrant converter
• 1st and 2nd quadrant
• 3rd and 4th quadrant
• Four-quadrant

Figure 5.10
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1st Quadrant Converter

• Both the voltage and the current are positive

Figure 5.8
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2nd Quadrant Converter

• Both the voltage is positive and the current is
  negative

Figure 5.11
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2nd Quadrant Converter
Figure 5.11
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1st and 2nd Quadrant Converter

• S1 and D4
• S4 and D1

Figure 5.12
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3rd and 4th Quadrant Converter

• S3 and D2
• S2 and D3

Figure 5.13
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Four Quadrant Converter
Figure 5.14
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Switching Mode Regulators

• Buck Regulator
• Boost Regulator
• Buck-Boost Regulator
• Cuk Regulator

Figure 5.15
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Buck Regulator
Figure 5.16
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Buck Regulator

• The critical values for a continuous inductor
  current and capacitor voltage

Figure 5.16
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Boost Regulator
Figure 5.17
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Boost Regulator

• The critical values for a continuous inductor
  current and capacitor voltage

Figure 5.17
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Buck-Boost Regulator
Figure 5.18
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Buck-Boost Regulator

• The critical values for a continuous inductor
  current and capacitor voltage

Figure 5.18
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Cuk Regulator
Figure 5.19
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Cuk Regulator
Figure 5.19
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Cuk Regulator

• The critical values for a continuous inductor
  current and capacitor voltage

Figure 5.19
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Rectified Fed Converter
Figure 5.23
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Input Filter
Figure 5.26
Figure 5.27
Figure 5.28
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Summary

• A dc-dc can convert a fixed dc voltage to a
  variable dc voltage.

• A four-quadrant converter allows power flow to
  and from load.

• Switching mode converter can produce output
  voltage higher and lower than the input voltage.
  

• The rectifier fed boost converter is commonly
  used for unity power factor correction (UPFC).
  

• What was the major idea?

• What was the muddiest idea?