FPGA based five-phase sinusoidal PWM generator

Multiphase machine has became popular in many rotational drive applications due to its reliability, high efficiency and high quality of waveforms. Moreover, this machine (e.g. 5-phase induction machine) can provide more options for selecting the most optimum voltage vector since the number of switching devices of the inverter increases that can enhance torque capability and improve dynamic performances. However, the great advantageous offered cannot be realized if the switching and control strategy performed at very low sampling frequency which does not guarantee for the multiphase drive to operate at optimum operations. This paper presents the realization of five-phase sinusoidal PWM signal generator at fast sampling frequency using one-chip programmable gate array (FPGA). It can be shown that the generation of sinusoidal PWM using FPGA can perform the switching frequency of the inverter at 40 kHz switching frequency that may raise potential for excellent drive performances

MATLAB/SIMULINK BASED ANALYSIS OF VOLTAGE SOURCE INVERTER WITH SPACE VECTOR MODULATION

Space vector modulation (SVM) is the best modulation technique to drive 3-phase load such as 3-phase induction motor. In this paper, the pulse width modulation strategy with SVM is analyzed in detail. The modulation strategy uses switching time calculator to calculate the timing of voltage vector applied to the three-phase balanced-load. The principle of the space vector modulation strategy is performed using Matlab/Simulink. The simulation result indicates that this algorithm is flexible and suitable to use for advance vector control. The strategy of the switching minimizes the distortion of load current as well as loss due to minimize number of commutations in the inverter

Review on Adjustable Speed Drive Techniques of Matrix Converter Fed Three-Phase Induction Machine

Adjustable Speed Drive (ASD) fed Matrix Converter is an interesting topic and is widely discussed in several articles. ASD provides many advantages, especially in the industrial sector because it increases work efficiency so as to reduce production costs. The induction machines construction is sturdy and its relatively inexpensive maintenance makes it more desirable in industrial process applications. Whereas the Matrix Converter (MC) construction without dc-link capacitors makes it more compact compared to conventional converters. This article discussed the ASD control modulation technique by using MC on a three-phase induction motor

Strategies for FPGA Implementation of Non-Restoring Square Root Algorithm

This paper presents three strategies to implement non restoring square root algorithm based on FPGA. A new basic building block is called controlled subtract-multiplex (CSM) is introduced in first strategy which use gate level abstraction. The main principle of the method is similar with conventional non-restoring algorithm, but it only uses subtract operation and append 01, while add operation and append 11 is not used. Second strategy presents the first strategy in register transfer level (RTL) abstraction. In third strategy, a modification for the implementation of conventional non-restoring algorithm is presented which also use RTL abstraction. The all above strategies is implemented in VHDL programming and adopt fully pipelined architecture. The strategies have conducted to implement successfully in FPGA hardware, and each of the strategies is offer an efficient in hardware resource. In generally, the third strategy is superior.DOI:http://dx.doi.org/10.11591/ijece.v4i4.600

High-Speed Computation using FPGA for Excellent Performance of Direct Torque Control of Induction Machines

The major problems in hysteresis-based DTC are high torque ripple and variable switching frequency. In order to minimize the torque ripple, high sampling time and fast digital realization should be applied. The high sampling and fast digital realization time can be achieved by utilizing high-speed processor where the operation of the discrete hysteresis regulator is becoming similar to the operation of analog-based comparator. This can be achieved by utilizing field programmable gate array (FPGA) which can perform a sampling at a very high speed, compared to the fact that developing an ASIC chip is expensive and laborious

A New Fixed Switching Frequency Direct Torque Controlled PMSM Drives with Low Ripple in Flux and Torque

Direct Torque Control (DTC) has gained popularity for development of  advanced  motor  control  due  to  its  simplicity  and  offers  fast  instantaneous torque  and  flux  controls.  However,  the  conventional  DTC  which  is  based  on hysteresis  controller  has  major  drawbacks,  namely  high  torque  ripple  and variable  inverter  switching  frequency.  This  paper  presents  an  improved switching strategy for reducing flux and torque ripples in DTC of PMSM drives; wherein  the  torque  hysteresis  controller  and  the  look-up  table  used  in  the conventional  DTC  are  replaced  with  a  constant  frequency  torque  controller (CFTC)  and  an  optimized  look-up  table,  respectively.  It  can  be  shown  that  a constant switching frequency is established due to the use of the CFTC while the reduction of torque and flux ripples is achieved mainly because of the selection of optimized  voltage  vector (i.e.  with an optimized  look-up  table).  This paper also  will  explain  the  construction  of  DTC  schemes  implemented  using MATLAB-Simulink  blocks.  Simulation  results  were  shown  that  a  significant reduction of flux and torque ripples which is about 90% can be achieved through the proposed DTC scheme.

Torque improvement of PM motor with semi-cycle stator design using 2D-finite element analysis

This paper presents sizing approaches to improve output torque performance in PM motor when partial stator body is removed. As the output torque performance is directly proportional to the electric loading, Q, modification on stator geometry affects the output torque performance and special procedures have to be taken to restore the desired output torque capability. Influences of split ratio, tooth body width, airgap and magnet thickness of  magnet in PM motor with asymmetry stator design are carried out and the performance verification are referred to the back-emf, average output torque, torque ripple as well as cogging torque. From the investigation using 2D-Finite Element Analysis, optimum size of tooth body width and optimum number of coil turns result better output torque while other sizing approaches result no significant change as quick saturation took place

Implementation Of Carrier-Based Simple Boost Pulse Width Modulation (PWM) For Z-Source Inverter (ZSI) Using Field Programming Gate Array (FPGA)

In recent years, the research on the Z-source inverter (ZSI) has received a wide acceptance due to its attractive solution for example in the renewable energy interface that requires voltage boost capability. The conventional inverter circuit based on the SPWM technique for example does not able to fully utilize its DC input voltage to produce a greater output voltage. The ZSI shoot-through implementation in high switching frequency requires a processor with fast sampling and high precision. In simulation, this can be easily carried out with the available advanced engineering software. In the hardware implementation however, the processor used is not only handle the switching, but also needs to read the data obtained by the sensor, voltage and current control, information display etc. This limits the capacity that can be used to implement the switching fast sampling with high precision. The aims of this work are to implement high precision of carrier-based simple boost PWM for ZSI using FPGA and to verify its real time hardware implementation. The high precision of PWM control algorithm based on the FPGA platform is verified by comparing the simulation results with the experimental results for different modulation index and boost factor, and a good agreement is concluded. It is observed that the application of FPGA reduces complexity, increases speed and the design of the switching technique can be altered without having to modify the hardware implementation

A New Fixed Switching Frequency Direct Torque Controlled PMSM Drives with Low Ripple in Flux and Torque

Direct Torque Control (DTC) has gained popularity for development of advanced motor control due to its simplicity and offers fast instantaneous torque and flux controls. However, the conventional DTC which is based on hysteresis controller has major drawbacks, namely high torque ripple and variable inverter switching frequency. This paper presents an improved switching strategy for reducing flux and torque ripples in DTC of PMSM drives; wherein the torque hysteresis controller and the look-up table used in the conventional DTC are replaced with a constant frequency torque controller (CFTC) and an optimized look-up table, respectively. It can be shown that a constant switching frequency is established due to the use of the CFTC while the reduction of torque and flux ripples is achieved mainly because of the selection of optimized voltage vector (i.e. with an optimized look-up table). This paper also will explain the construction of DTC schemes implemented using MATLAB-Simulink blocks. Simulation results were shown that a significant reduction of flux and torque ripples which is about 90% can be achieved through the proposed DTC scheme