This document presents a wind energy conversion system using a permanent magnet synchronous generator (PMSG) connected to a T-source three-phase matrix converter. The system aims to efficiently harness wind power and deliver it to a load. A PMSG is connected to a three-phase diode rectifier and input capacitors, with the output fed to a T-source network and three-phase matrix converter. The converter can boost output voltage regardless of input voltage and regulate it through shoot-through control. MATLAB/Simulink models are developed and simulations show the converter produces controlled output voltage and current waveforms to power the load efficiently with fewer components than traditional converter topologies.

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Wind Energy Conversion System Using PMSG with
T-Source Three Phase Matrix Converter
K.T.Maheswari1
Assistant Professor,
1
Department of Electrical and Electronics Engineering,
Bannari Amman Institute of Technology
Erode, India
maheswarikt@gmail.com
S.Viswanathan2
PG Scholar,
2
Department of Electrical and Electronics Engineering,
Bannari Amman Institute of Technology
Erode, India
Viswa3e@gmail.com
Abstract-This paper presents an analysis of a PMSG wind power system using T-Sourcethree phase matrix converter. PMSG using T-
Source three phase matrix converterhas advantages that it can provide any desired AC output voltage regardless of DC input with
regulation in shoot-through time. In this control system T-Source capacitor voltage can be kept stable with variations in the shoot-
through time, maximum power from the wind turbine to be delivered. Inaddition, of a new future, the converter employs a safe-
commutation strategy toconduct along a continuous current flow, which results in theelimination of voltage spikes on switches without
the need for a snubber circuit. With the use of matrix converter the surely need forrectifier circuit and passive components to store
energy arereduced. The MATLAB/Simulinkmodel of the overall system is carried out and theoretical wind energy conversion output
load voltage calculations are madeand feasibility of the new topology has been verified and that theconverter can produce an output
voltage and output current. This proposed method has greater efficiency and lower cost.
Index Terms- Matrix Converter (MC),Maximum Power Point Tracking (MPPT),Permanent Magnet Synchronous Generator (PMSG),
T-Source Inverter (TSI), Z-Source Inverter (ZSI).
————————————————————
1. INTRODUCTION
he renewable energy sources gained special importance over
the years because of depletion of conventional energy
sources. Wind energy is a very important renewable energy
source and lots of technologies have been introduced to fetch
power from wind energy.
PMSG wind power system using T-Source three phase matrix
converter is an efficient way of harnessing power.Permanent
magnet synchronous generator has numerous merits like high
power factor, high efficiency, and low cost, gearless operations.
PMSG system includes diode rectifier, boost DC-DC converter
and three phase inverter [4-6]. Control of inverter provides
extracted power to the utility load side and boost converter is
controlled for maximum power point tracking (MPPT).
This system becomes complex, expensive because of extra
active devices and controls.T-Source inverter overcomes voltage
limitations of traditional inverter voltage is boosted with single
stage converter, both switches in the same inverter must turn ON
in same time that is shoot-through state, due to this shoot-through
state short circuit across any phases leg is allowed therefore
reliability of system greatly improved [8].
Based on the advantages of T-Source three-phase matrix
converters this paper presents application of T-Source inverter
connected to wind power system which uses PMSG and
generated power deliver to load.
Fig.1.General Block Diagram of the Proposed Topology
2. T-SOURCE INVERTER
As with a conventional ZSI [1], the TSI can handle, shoot through
states when both switches in the same phase leg are turned on.
The T-Source network is used instead of the LC-network for buck
the output voltage by inserting shoot through states in the PWM
[5-8].
TSI operates in two modes:
1) Shoot through Mode
2) Non Shoot through Mode.
2.1Shoot through Mode
Fig.2 shows the equivalent circuit of T – source inverter in shoot
through mode operation. This shoot through a zero state in
traditional voltage source inverter. It can be obtained in three
T

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different ways, such as shoot through via any one phase leg or
combination of two phase leg. During this mode, diode is reverse
biased, separating DC link from the AC line. A desired voltage
can be maintained at the output by controlling the interval of
shoot through state.
Fig.2. Shoot ThroughMode
Thus the T–Source inverter highly improves the reliability of the
inverter since short circuit across any phase leg is allowed and it
cannot destroy the switches in the inverter.
2.2 Non – Shoot through Mode
Fig.3. shows the equivalent circuit of TSI in Non – shoot through
mode operation. In this mode, the inverter bridges operate in one
of traditional active states, thus acting as a current source when
viewed from T –source circuit [8]. During active mode, voltage
impressed across load.
Fig.3. Non-Shoot Through Mode
The diodes conduct and carry current difference between the
inductor current and input DC current. Note that both the
inductors have an identical current because of coupled inductors.
The T-Source network can operate in six possible states, in which
three states are desired while the other three are undesirable. And
the undesirable states can be avoided by choosing appropriate
values of the inductors and capacitors of the impedance network.
3. THREE-PHASE MATRIX CONVERTER
The important advantage of matrix converter is elimination of
theDC link filter in circuits. Zero switching loss devices can
transfer input power to output power without any other loss. But
practically it does not exist. The switching frequency only decides
THD of the converter. Maximum power transfer to the load is
decided by the nature of the control algorithm. Matrix converter
has a maximum input, output voltage transfer ratio limited to 60-
87 % for sinusoidal input and output waveforms, which can be
improved. Further, matrix converter requires more semiconductor
devices than a conventional AC-AC indirect power frequency
converter. Since monolithic bi-directional switches are available,
they are used for switching purposes of the converter.
3.1 Three Phase Matrix Converter
The instantaneous power flow path does not have to equal power
output. The main difference between the input and output power
must be absorbed or delivered by an energy storage element
within the converter.The matrix converter replaces the multiple
conversion stages and the intermediate energy storage element by
a single power conversion stage, and uses a matrix of
semiconductor bidirectional switches connecting input and output
terminals. With this general arrangement of switches, the power
flow through the converter can reverse. Because of the absence of
any energy storage element, the instantaneous power input must
be equal to the power output, assuming ideal zero-loss
switches.However, the reactive power input does not have to
equal power output. It can be said again that the phase angle
between the voltages and currents at the input can be controlled
and does not have to be the same as at theoutput three phase
matrix converter consists of only nine bi-directional switches.
Fig.4.General Architecture of Three Phase Matrix Converter
It has been arranged into three groups of three switches. Each
group is connected to each phase of the output only. These
arrangements of switches can connect any input phaseonly [2-4].
3.2 Commutation Methodsusing in Matrix Converter
The commutation has to be actively controlled at all times. It is
important that no two bidirectional switches are switched on at
the same time. This results in short circuit at capacitor input and
open circuit at inductive load occurs. There are two different
types of commutation of the matrix converter available and it is
explained in the following section.
3.2.1 Dead Time Commutation of matrix converter
This type of commutation method is used in the inverter side only
provided. It means that load current freewheel to throw
antiparallel diode during the dead time period. In a case of the
matrix converter dead time commutation method is useless. It
results in the open circuit at the load side only. Then forced spike
only occurs across the switches. To avoid this snubber clamping
devices are provided this method. This is a power path to the load
current during the dead time and hence the design of snubber
circuit is more difficult[10].

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3.2.2 Current Commutation Based on Multiple Steps using
matrix converter
This type of commutation uses bidirectional switches. These are
more reliable in current commutation and obey the basic rules. It
can be able to control the direction of the current. This strategy is
essential in case of controlled current flow. This commutation
technique relies on knowledge of the output current direction.
This current direction can be difficult to reliably determine and
allow current levels in high power drives.
To avoid this problem a technique of using the voltage across the
bi-directional switch to determine the current direction has been
developed. This technique provides reliable, current commutation
using an intelligent gate drive circuit which controls the firing of
the IGBTs and detects the direction of current flow within the
bidirectional switch cell. The current direction information
calculated by the active gate drive is passed to all the other gate
drivers on the same output leg.
In this way all the gate drivers contribute to operate a safe
commutation. In matrix converter commutation issue is taken
care by Matlab simulation. Forced commutation is an employed
throughout the process.
3.3 PMSG Using Wind Energy Conversion System
The PMSG wind power system with T-Source three phase matrix
converter based load side connected.This configuration includes a
PMSG is connected to three phase diode rectifier with the input
capacitors (CA, CB and CC), a T-Source network, and inverter
system connected to load side [3]. The purpose of the input
capacitors is to serve as the DC source feeding the T-Source
network. The voltage of the generator fed to the T-Source inverter
varies according to the generator speed[6-7-9].
It is assumed that the DC voltage fed to the T-Source inverter
where VLL is the line to line voltage of the generator.
𝑉𝑑𝑐 =
3 3
𝜋
𝑉𝐿𝐿
In boost operating mode that is in shoot through state, the peak
DC link voltage across the inverter bridge is expressed as
𝑉𝑖 = 𝑋. 𝑉𝑑𝑐
Where VDC is the source voltage and X is the boost factor that is
determined by
𝑋 =
𝑡
𝑡 − 2𝑡𝑜
≥ 1
Wheretois the shoot-through time interval over a switching cycle
T.
The capacitors voltage can be expressed as bellow
𝑉𝑐 =
𝑡 − 𝑡𝑜
𝑡 − 2𝑡𝑜
𝑉𝑑𝑐 ≥ 𝑉𝑑𝑐
The capacitor voltage can be boosted by adjusting the shoot-
through time.
The output peak phase voltage can be expressed as
𝑉𝑎𝑐 = 𝑌. 𝑋
𝑉𝑑𝑐
2
The peak output phase voltage can be controlled both by
adjusting the modulation index or shoot-though time.
4. SIMULATION RESULTS
4.1 The Proposed Simulink Model of Three Phase Matrix
Converter
Fig.5.Simulink /Matlab simulation of Three Phase Matrix
Converter
4.2 Simulink Results for Output Voltage waveform for three
phase matrix converter
Fig.6. Simulink /Matlab simulation results, Output Voltage
waveform for three phase matrix converter
4.3 Simulink Results for Output Current waveform for three
phase matrix converter
Fig.7. Simulink /Matlab simulation results, Output Current
waveform for three phase matrix converter

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4.4 T-Source Three Phase Matrix Converter Pwm Pulse
Generation
Fig.8.Simulink Model of T-Source Three Phase Matrix
Converter Pwm Pulse Generation
4.5 PWM Pulse Generation
Fig.9. Simulink /Matlab simulation results, Sinusoidal Pwm
Pulse Generation
4.6 Comparison of Carrier and Reference Waveforms
Fig.10.Simulink Model of Carrier and Reference Waveforms
4.7 The Proposed Simulink Model of PMSG Using T-Source
Three Phase Matrix Converter
Fig 11.Simulink /Matlab simulation of PMSG Using T-Source
Three Phase Matrix Converter
4.8 Simulink Results for Output Voltage waveform for PMSG
Using T-Source Three Phase Matrix Converter
Fig.12. Simulink /Matlab simulation results, Output Voltage
waveform for PMSG Using T-Source Three Phase Matrix
Converter
4.9 Simulink Results for Output Current waveform for
PMSG Using T-Source Three Phase Matrix Converter
Fig.13. Simulink /Matlab simulation results, Output Current
waveform for PMSG Using T-Source Three Phase Matrix
Converter
5. CONCLUSION
In this paper, the PMSG wind power system connected to load
using T-source three phasematrix convertersare proposed. The
proposed system worked effectively with the input DC voltage
lower than the load level voltage. The converter employs a safe-
commutation strategy toconduct along a continuous current flow,
which results in theelimination of voltage spikes on switches
without the need for a snubber circuit. The proposed system
extracted the power from wind turbine and delivered high quality
voltage and current into the load side calculated by using
MATLAB/Simulink. The proposed T-source three matrix
convertersare more efficient, cost effective and have high
performance.
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AUTHOR PROFILE:
 K.T.Maheswari is currently working as Assistant Professor
in Bannari Amman Institute of
technology,India,Ph:9788459307,
E-mail: maheswarikt@gmail.com
 S.Viswanathan is currently pursuing Master of Engineering
in Bannari Amman Institute of Technology,
India,Ph:9585308233,
E-mail:viswa3e@gmail.com