23-05-2012, 10:48 AM
Hybrid Cascaded Multilevel Inverter with PWM Control Method
[attachment=22800]
INTRODUCTION
The multilevel inverter has gained much attention in
recent years due to its advantages in high power with low
harmonics applications. The general function of the
multilevel inverter is to synthesize a desired high voltage
from several levels of dc voltages that can be batteries,
fuel cells, etc.
In this paper, the proposed hybrid cascaded multilevel
inverter includes a standard 3-leg inverter (one leg for
each phase) and H-bridge in series with each inverter leg.
It can use only a single DC power source to supply a
standard 3-leg inverter along with three full H-bridges
supplied by capacitors. Traditionally, each H-bridge
requires a DC power source [1-5]. Multilevel carrierbased
PWM method is used to produce a five level phase
voltage.
EXPERIMENT VERIFICATION
A 5 kW prototype using power MOSFETs (100V,
180A) as shown in Fig. 7 has been built in order to verify
the proposed hybrid multilevel inverter. The load is a 15
hp three-phase induction motor, which is loaded less than
5 kW. An Altera FLEX 10K field programmable gate
array (FPGA) controller is used to implement the control
algorithm to drive the motor with the real-time variable
output voltage and variable frequency.
The FPGA controller is designed as a card to be
plugged into a personal computer, which uses a
peripheral component interconnect (PCI) bus to
communicate with the microcomputer in which a Visual
Basic interface is used to input and adjust the control
schemes and parameters.
CONCLUSION
A simulation model for the hybrid multilevel inverter
is developed in PSIM and SIMULINK co-simulation
platform. The inverter output is a five level phase
voltage. The paper presents the main circuit model in
PSIM and simulation results in detail. The experiment
and FFT analysis results verified the proposed hybrid
cascaded multilevel inverter with a PWM control
method.
[attachment=22800]
INTRODUCTION
The multilevel inverter has gained much attention in
recent years due to its advantages in high power with low
harmonics applications. The general function of the
multilevel inverter is to synthesize a desired high voltage
from several levels of dc voltages that can be batteries,
fuel cells, etc.
In this paper, the proposed hybrid cascaded multilevel
inverter includes a standard 3-leg inverter (one leg for
each phase) and H-bridge in series with each inverter leg.
It can use only a single DC power source to supply a
standard 3-leg inverter along with three full H-bridges
supplied by capacitors. Traditionally, each H-bridge
requires a DC power source [1-5]. Multilevel carrierbased
PWM method is used to produce a five level phase
voltage.
EXPERIMENT VERIFICATION
A 5 kW prototype using power MOSFETs (100V,
180A) as shown in Fig. 7 has been built in order to verify
the proposed hybrid multilevel inverter. The load is a 15
hp three-phase induction motor, which is loaded less than
5 kW. An Altera FLEX 10K field programmable gate
array (FPGA) controller is used to implement the control
algorithm to drive the motor with the real-time variable
output voltage and variable frequency.
The FPGA controller is designed as a card to be
plugged into a personal computer, which uses a
peripheral component interconnect (PCI) bus to
communicate with the microcomputer in which a Visual
Basic interface is used to input and adjust the control
schemes and parameters.
CONCLUSION
A simulation model for the hybrid multilevel inverter
is developed in PSIM and SIMULINK co-simulation
platform. The inverter output is a five level phase
voltage. The paper presents the main circuit model in
PSIM and simulation results in detail. The experiment
and FFT analysis results verified the proposed hybrid
cascaded multilevel inverter with a PWM control
method.