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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN 0976 – 6553(Online) Volume 5, Issue 6, June (2014), pp. 17-29 © IAEME 17 ENHANCED FAULT RIDE-THROUGH TECHNIQUE FOR PMSG WIND TURBINE SYSTEMS USING DC LINK BASED ROTOR-SIDE CONTROLLER Anas Abdulqader khalaf Bharati Vidyapeeth Deemed University, Pune ABSTRACT In the field of renewable energy generation has been observed wind energy. Where the technology is more rapid growth. It attracts attention as one of the most effective ways in terms of the cost of generating electricity from renewable energy sources. The system wind generation has application for support grid. Voltage of the wind generator permanent magnet synchronous generator (PMSG) is directly driven by a variable due to the sporadic nature of wind energy. Voltage fluctuation and power of major concern in the connected network systems generate electricity using a wind converter list. Inverter is essential for interaction of from wind sources with Ac network. There are many as possible inverter the topology and inverter switch plans and each one will have its comparative advantages and disadvantages. Synchronous generators used a variable speed the permanent magnet to extract the utmost of energy from wind energy conversion system. The is suggested common strategy for power control the permanent magnet synchronous generator a system based on wind energy conversion (WECS) operating under different the network conditions. In the strategy, is used by the converter generator to dominate the voltage The DC link converter side of the network is responsible for the controlling the energy flow injected into the grid. Console by the generator has the potential inherent damping of torsional oscillations caused by the characteristics of the drive train. It uses the control of the part of the grid to meet the (power) requirements of active and reactive current laws specified in the grid. At the same time alleviate the distortions from the current network fault even with non-symmetric. Errors through the network, the converted by the generator automatically reduces the current transformers to keep the prey DC voltage generator acceleration caused by that organization Pitch. Compared with the traditional strategy, chopper, DC, which aims to help ride through the fault of the WECS, Could be eliminated if you use the proposed plan. Compared with the control system variable regulator. The proposed strategy has the responses faster and more accurate power which is beneficial to the recovery grid. The simulation results CHECK the effectiveness of proposed strategies. The hybrid control scheme proposed for energy storage systems (ESS), helicopters braking fault ride through the capability and suppress fluctuation INTERNATIONAL JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY (IJEET) ISSN 0976 – 6545(Print) ISSN 0976 – 6553(Online) Volume 5, Issue 6, June (2014), pp. 17-29 © IAEME: www.iaeme.com/ijeet.asp Journal Impact Factor (2014): 6.8310 (Calculated by GISI) www.jifactor.com IJEET © I A E M E
Transcript
Page 1: 40220140506002

International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print),

ISSN 0976 – 6553(Online) Volume 5, Issue 6, June (2014), pp. 17-29 © IAEME

17

ENHANCED FAULT RIDE-THROUGH TECHNIQUE FOR PMSG WIND

TURBINE SYSTEMS USING DC LINK BASED ROTOR-SIDE

CONTROLLER

Anas Abdulqader khalaf

Bharati Vidyapeeth Deemed University, Pune

ABSTRACT

In the field of renewable energy generation has been observed wind energy. Where the

technology is more rapid growth. It attracts attention as one of the most effective ways in terms of

the cost of generating electricity from renewable energy sources. The system wind generation has

application for support grid. Voltage of the wind generator permanent magnet synchronous generator

(PMSG) is directly driven by a variable due to the sporadic nature of wind energy. Voltage

fluctuation and power of major concern in the connected network systems generate electricity using a

wind converter list. Inverter is essential for interaction of from wind sources with Ac network. There

are many as possible inverter the topology and inverter switch plans and each one will have its

comparative advantages and disadvantages. Synchronous generators used a variable speed the

permanent magnet to extract the utmost of energy from wind energy conversion system. The is

suggested common strategy for power control the permanent magnet synchronous generator a system

based on wind energy conversion (WECS) operating under different the network conditions. In the

strategy, is used by the converter generator to dominate the voltage The DC link converter side of the

network is responsible for the controlling the energy flow injected into the grid. Console by the

generator has the potential inherent damping of torsional oscillations caused by the characteristics of

the drive train. It uses the control of the part of the grid to meet the (power) requirements of active

and reactive current laws specified in the grid. At the same time alleviate the distortions from the

current network fault even with non-symmetric. Errors through the network, the converted by the

generator automatically reduces the current transformers to keep the prey DC voltage generator

acceleration caused by that organization Pitch. Compared with the traditional strategy, chopper, DC,

which aims to help ride through the fault of the WECS, Could be eliminated if you use the proposed

plan. Compared with the control system variable regulator. The proposed strategy has the responses

faster and more accurate power which is beneficial to the recovery grid. The simulation results

CHECK the effectiveness of proposed strategies. The hybrid control scheme proposed for energy

storage systems (ESS), helicopters braking fault ride through the capability and suppress fluctuation

INTERNATIONAL JOURNAL OF ELECTRICAL ENGINEERING &

TECHNOLOGY (IJEET)

ISSN 0976 – 6545(Print) ISSN 0976 – 6553(Online) Volume 5, Issue 6, June (2014), pp. 17-29

© IAEME: www.iaeme.com/ijeet.asp Journal Impact Factor (2014): 6.8310 (Calculated by GISI) www.jifactor.com

IJEET

© I A E M E

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ISSN 0976 – 6553(Online) Volume 5, Issue 6, June (2014), pp. 17-29 © IAEME

18

the power output of the permanent magnet synchronous generator (PMSG) of wind turbine systems.

Errors through the grid. In DC link is controlled by the voltage link ESS rather than converting both

sides of the line (LSC). While LSC is utilized as a STATCOM to inject the current recession in the

grid to assist in the voltage grid.

Index Terms: PMSGs, WECS, ESS, STATCOM, LSC.

LITERATURE SURVEY

1) Modelling of grid-connected wind driven by the system using PMSG Rungs Kota method:

Like the wind farm PMSG connected to the grid by solving differential equations which

describe the using the method of Rungs Kota (Sermutlu 2004) as described by the RESOLUTION

graph ends with temporal variation from currents. Voltages The active energy and reactive.

2) Wind power grid-connected Chipmunks cage induction generator (SCIG) the system:

The wind driven by SCIG, The associated stator winding straight to the network and driven

by the rotor from of wind turbines is converted to energy captured by of wind turbines into electrical

energy by induction generator The broadcast on the grid by the pro-winding. Are controlled in a

corner of the pitch in order to reduce the production of generator power to their face value at high

wind speeds. In order to generate energy, it must be induction generator the speed of slightly higher

than synchronous speed. Is providing reactive force absorbed by the induction generator by the grid

or by certain devices such as the capacitor the banks, SVC, STATCOM or synchronous condenser

(The Math Works 2008A) The analysis is based on transient current the system simulation on

MATLAB / SIMULINK for approximate wind speeds fixed and variable.

3) grid-connected wind power doubling Fed Induction Generator (DFIG) the system:

The wind driven by doubling-fed induction generator (WTDFIG) Adapter AC / DC / AC

linking among the rotor of the generator to the grid. Split transforms AC / DC / AC to the two

components: The rotor side transforms (RSC) and the grid side transforms (GSC) and adapters are

voltage sources that use IGBTs confined forced to compile AC voltage from a DC voltage source.

And synthesizing voltage AC is at the frequency of the power and for the slip frequency for us. A

capacitor connected to the DC side acts serves as the source of DC voltage. The of Couplings

inductor L use a to connect to the grid. The rotor is connected to a three-phase filter by slip rings and

brushes The associated stator three-phase filter straight to the grid. Is converted to energy captured

by the wind turbines into electrical power by induction generator and transmitted to the grid from the

stator and rotor windings. Control system generates a corner of the pitch signals fait accompli default

and effort of VGC and respectively for control of the power compared to the wind turbines against

the authorities of reference which have been obtained from the flow characteristic. A Proportional-

Integral (PI) regulator is used to limit the power error to zero. While adjusting the bus voltage DC

and reactive force or voltage The network stations (The Math Works 2010A). Compared to the

system SCIG, The is based on transient analysis of the current the system also DFIG simulation

MATLAB / SIMULINK for approximate wind speeds fixed and variable.

Compare DESIGN OF WIND TURBINE BASED PMSG between literature survey

CONTROL SCHEME and PROPOSED CONTROL SCHEME A PMSG-based WECS is simulated and analyzed when subjected to the system faults. the

PMSG-based wind power unit connected to the utility grid via a step-up transformer and

transmission line. This PMSG-based WECS was implemented in MATLAB/ SIMULINK, where the

above three different converter models are used separately for the purpose of comparison.

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Design of the Unified Power Control for the MW Class PMSG-Based WECS IN matlab

Fig. 1: PMSG BASED WECS WITH DC CHOPPER

Fig. 2: PMSG BASED WECS WITH OUT DC CHOPPER

We have different between the CONVENTIONAL CONTROL SCHEME and PROPOSED

CONTROL SCHEME in block diagram (RSC)and(GSC) in fig3 .fig4 .fig5 fig6

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Fig 3: the system RSC in proposed control scheme

Fig. 4: the system RSC literature survey control scheme

Fig. 5: the system GSC in proposed control scheme

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Fig. 6: the system GSC literature survey control scheme

SIMULATION RESULTS WITH PROPOSED AND LITERATURE SURVEY

1) Operation With Unsymmetrical Grid Faults

A)With literature survey without Dc chopper and proposed technique with chopper –AG:

Fig. 7: Rotor speed, EM torque and stator ‘A’ phase current for literature survey control scheme

system for AG fault

Fig. 8: Rotor speed, EM Torque and stator ‘A’ phase current for proposed system with chopper for

un symmetrical fault AG

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Fig. 9: DC link voltage for literature survey control scheme without dc chopper system for AG fault

Fig. 10: DC link voltage for proposed system with chopper for un symmetrical fault AG

Fig. 11: stator voltage and current for literature survey without dc copper control scheme system for

AG fault

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Fig. 12: Grid voltage and current for proposed system with chopper for un symmetrical fault AG

B) With literature survey without dc chopper and proposed technique with chopper –abg fault

Fig. 13: Rotor speed, EM torque and stator ‘A’ phase current for literature survey without dc

chopper control scheme system for ABG fault

Fig. 14: Rotor speed, EM Torque and stator ‘A’ phase current for proposed system with chopper for

un symmetrical fault ABG

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Fig. 15: DC link voltage for literature survey control scheme system for ABG fault

Fig. 16: dc link voltage across capacitor for proposed system with dc chopper for un symmetrical

fault ABG

Fig. 17: stator voltage and current for literature survey control scheme system for ABG fault

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Fig. 18: Grid voltage and current for proposed system with chopper for un symmetrical fault ABG.

2) Operation With Symmetrical Grid Faults: With literature survey without dc copper and proposed

with dc chopper technique

Fig. 19: Rotor speed, EM Torque and stator ‘A’ phase current for proposed system with chopper

It can be observed that speed and torque oscillations were high without chopper compared to

with chopper and stator current drops to nearly zero value.

Fig. 20: Rotor speed, EM torque and stator ‘A’ phase current for literature survey without dc

chopper control scheme system for ABCG fault

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Fig. 21: DC link voltage for proposed system without chopper symmetrical fault

The DC link voltage at capacitor also decreases from 1000V to zero without chopper and

voltage decreases from 1000V to 400Volts. Hence voltage can be maintained much better with

chopper circuit. It can also be verified that voltage and current at generator terminals decreases from

unity pu to zero value without chopper and is maintained at 0.1pu with chopper.

Fig. 22: DC link voltage for literature survey without dc chopper control scheme system for ABCG

fault

Fig. 23: Grid voltage and current for proposed system with dc chopper for symmetrical fault

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Fig. 24: stator voltage and current for literature survey control scheme system for ABCG fault

CONCLUSION

The converter-based WECS has the potential to improve the transient stability of the power

system because of its quick power response. However, the rating of power devices limits its

applications. In order to make maximal use of such systems, advanced control technique should be

developed to satisfy the requirements of the power systems. The conventional control strategy for the

PMSG-based WECS is mainly designed to promise the proper operation of the generator. In the

strategy, the generator torque (power) is directly controlled while the grid side power is indirectly

regulated. The disturbance at the generator side will aggravate the power responses at the grid side,

which is not desired by the PSO. The basic idea of the proposed strategy is to first satisfy the power

system requirements under different grid conditions. In the strategy, the active/reactive current

(power) is directly regulated through the grid-side converter. In order to provide enough oscillation

damping, additional active damping loop is integrated into the generated-side controller. Compared

with the conventional or variable-structured control strategies, the proposed one has the quickest and

most precise grid-side current (power) responses. During grid fault, no Dc chopper or controller

switching is necessary with the strategy and the current distortions can be mitigated when the

unsymmetrical grid fault occurs. Moreover, the proposed strategy requires no system parameters and

is simple to implement, which makes it attractive for the engineering practice. However, such a

strategy sacrifices the response of the generator-side variables and leads to the fluctuation of the dc-

link voltage. It is believed that a large dc-link capacitor can be helpful to improve the system

performance if the proposed strategy is employed.

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