1. POWER SEMICONDUCTOR SYSTEMS I Author: Ales Havel E-mail: ales.havel@vsb.czales.havel@vsb.cz Phone number: 4287 Headquarters: E227 Web page: http://homen.vsb.cz/~hav278/

2. Presentation contents  Main types of converters  AC-DC converters Single phase rectifiers Construction possibilities, wiring Load voltage and current waveforms Mathematics Neat examples Three phase rectifiers Construction possibilities, wiring Load voltage and current waveforms Mathematics Neat examples  DC-DC converters  DC-AC converters  AC-AC converters

3. Power converters  A power semiconductor converter is an electrical device for converting electrical energy.

4. Division of AC/DC converters  Properties of rectifiers  Number of input phases Single phase rectifiers Three phase rectifiers n – phase rectifiers  Number of pulses P = 1, 2, 3, 6…  Possibilities of output voltage control Without control Diode rectifiers Half-controlled rectifiers Diodes + Thyristors Full-controlled rectifiers Thyristors  Wiring Bridge rectifiers Node rectifiers

5. Half-wave single phase diode rectifiers Voltage Current Resistive load Inductive load

6. Half-wave single phase diode rectifiers Voltage Current R+L+D0 load R+L load

7. Half-wave single phase diode rectifiers Voltage Current R+C load R+V load

8. Two pulse diode rectifiers Voltage Current

9. Two pulse thyristor controlled rectifiers

10. Important mathematical relations Output to Input phase RMS voltage ratio p[-]U L / U 1 [-] 10.45 20.90 31.17 62.34 Limit of load current continuity for resistive load p[-]α[°] 330 660 The output AVG voltage of diode rectifier or thyristor rectifier with control angle α = 0°: The output AVG voltage of thyristor rectifier with control angle α. Condition 1: The load current must be continuous Condition 2: No parallel bypass diode on the load

11. Example 1- submission Calculate the output AVG voltage of the 2-pulse bridge controlled rectifier, if you know the following values: α = 60°, U 1 = 230V

12. Example 1- solution a) General calculation approach: b) Calculation utilizing the basic relation: c) Calculation utilizing the table values:

13. Example 1- question? How will change the output AVG voltage value if we use the bypass diode parallel to the load? Solution:

14. Six pulse thyristor controlled rectifiers

16. Thank You for your attention