multi level inverter for drive application part 1

1. SYED LATEEF UDDIN B110877EE
K. PRUDHVI KUMAR B110921EE
S. RAVI PRAKASH REDDY B110494EE
Y. ROHITH B110901EE
MULTILEVEL INVERTER FOR DRIVE
APPLICATIONS

2. Multi level inverters are increasingly being considered for high power
applications because –
 They can operate at higher output voltages.
 They produce low levels of harmonic components in the switched
output voltages.
 Multi level inverters are used in medium to high voltage level
applications such as – motor drive systems, power distribution,
power quality, etc.

3. Cascaded H Bridge Inverters
Diode Clamped Inverters (neutral clamped).
Flying Capacitor Inverters (capacitor clamped).
In this project, we dealt with the Cascaded H-Bridge Inverter
structure.

4. Sinusoidal pulse width modulation (SPWM).
Space vector pulse width modulation (SVPWM).
Others.

5. To conduct simulation exercises for 3-phase cascaded H-bridge
inverter for 3-level and 5-level on Matlab Simulink.
To generate gating signals using DSP Processor.
To implement a 3-Phase 3-level inverter practically for drive
applications.

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10. Simulation of 3 Phase 3 Level Inverter

11. SVPWM SUB-SYSTEM
Sub-system for generating SV
Modulating wave

14. TMS320F28335 DSP KIT

15. GENERATING GATING SIGNALS USING DSP PROCESSOR
(TMS320F28335)
 The simulation and generation of the signals has been done using
Code Composer Studiov6.0.0 and a TMS320F28335 DSP Starter kit.
 CCS includes tools for code generation, such as a C compiler, an
assembler, and a linker.
 TMS320F28335 is a floating point device with 12 EPWM outputs.
 EPWM module supports some important features like –
1. Dedicated 16-bit time-base counter with period and frequency
control.
2. Dead-band generation with independent rising and falling edge
delay control.
3. Programmable phase-control support for lag or lead operation
relative to other EPWM modules.

16. GENERATION OF SPACE VECTOR PWM SIGNALS
 Generation of Triangular waveform:
Triangular wave can be generated using the timer which is
incorporated in the processor.
 Comparison of triangle wave with SV Modulating wave samples:

17. HARDWARE IMPLEMENTATION OF GATE DRIVE CIRCUIT
 Power of the signals generated from the DSP processor
are not sufficient for driving the switches
 This makes us to use the gate driver circuit.
 It also isolates control circuit from power circuit.
 A gate driver consists of a level shifter in combination with an
amplifier.
 An IC named TLP250 is used for both isolating and amplifying.
OPTO COUPLER

18. TLP250
 Output of
TLP250 is of12V
 The input to the driver circuit
is from (TMS320F28335) of 3.3V
magnitude.

19. GATE DRIVE PULSES (PHASE-A)
Gate drive pulses of First leg of R-phase
Gate drive pulses of Second leg of R-phase

20. DEAD BAND IN COMPLIMENTARY GATE SIGNALS

21. Experimental setup of Gate Driver circuit

22. Experimental setup of Gate Driver circuit

23. Simulation exercises were conducted on 3 phase 3-level and 5-
level inverters on MATLAB SIMULINK using SPWM & SVPWM.
DSP processor (TMS320F28335) is used for generating gating
pulses.
Gate drive circuit is practically implemented for 3 level inverter.

24. A 3 phase 3 level inverter is to be practically implemented.
Speed control of 3 phase induction motor has to carried out
done using open loop V /f control method.
THD analysis will be performed for comparing Sine and Space
vector modulation techniques.

25. THANK YOU