Flying Capacitor Multi Level Inverter

It gives the basic Idea about Inverter than moving towards the advantages of Multilevel Inverter .In this PPT main focus on Flying Capacitor Multilevel Inverter.

1. TOPIC- FLYING CAPACITOR MULTILEVEL INVERTER ADVANCED POWER ELECTRONICS SHEIKH MOHAMMAD SAJID RCoEM M. TECH 1 ST Sem Roll no - 07

2. INVERTER Inverter converts DC volatge into variable magnitude and variable frequency AC voltage. Ideally , Purelly sinusoidal output voltage. Practically not possible. PWM technique makes the task of extracting sinusoidal voltage from the output of inverter easier.

3. 3-PHASE FULL BRIDGE VSI

4. 3-PHASE FULL BRIDGE VSI WAVEFORM

5. ADVANTAGES OF MULTILEVEL INVERTER Reduced harmonic distortion - Multilevel converters not only can generate the output voltages with very low distortion, but also can reduce the dv/dt stresses, therefore electromagnetic compatibility (EMC) problems can be reduced. Common-mode(CM) voltage - Multilevel converters produce smaller CM voltage; therefore, the stress in the bearings of a motor connected to a multilevel motor drive can be reduced. Input current - Multilevel converters can draw input current with low distortion. Switching frequency- Multilevel converters can operate at both fundamental switching frequency and high switching frequency PWM. It should be noted that lower switching frequency usually means lower switching loss and higher efficiency.

6. FLYING CAPACITOR MULTILEVEL INVERTER This inverter uses capacitor to limit the voltage of power devices. The configuration of the flying capacitor multilevel inverter is like a diode clamped multilevel inverter except that capacitor are used to devide the input DC voltage. The voltage over each capacitor and each switch is Vdc.

7. FLYING CAPACITOR 3 LEVEL INVERTER

8. FLYING CAPACITOR 3 LEVEL INVERTER

9. FLYING CAPACITOR 5-LEVEL INVERTER

10. FLYING CAPACITOR 5-LEVEL

11. COMPONENT COUNT OF FLYING CAPACITOR The number of components in one leg of inverter are as follows: Number of active switches =2*(m-1) Number of flying capacitors = (m-1) Number of cascade capacitors = {(m-1)(m-2) }/2

12. ADVANTAGES Real as well as active power flow is controlled. Since more number of capacitor are used, short duration outages and voltage sag does not affect much as load side. Low harmonic content. Redundancies are available to balance different voltage levels. Large number of capacitors make inverter bulky. Inverter content is very complicated. Poor efficiency for real power transmission . DISADVANTAGES

13. APPLICATIONS OF MULTILEVEL INVERTER High-voltage and Medium-voltage motor drives High voltage DC transmission Flexible AC transmission system (FACTS) Traction Active filtering Utility interface for renewable energy systems