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Saturday, 20 March 2021

Novel Single Stage Power Factor Corrected LED Driver Topology for Space Constrained Applications of Aircraft Exterior Lighting System

ABSTRACT:

 This paper proposes a novel converter topology based on a single stage LED driver with Power Factor Correction (PFC) which is optimized for weight, volume and cost, for space constrained environments such as Aerospace exterior lighting product. The proposed topology utilizes a single switch to harmonize the input current as well as control the intensity of lighting system. A typical Power Factor Pre-regulator (PFP) uses a bulk energy storage capacitor, which is subjected to wear out a higher altitudes due to low pressure conditions and freezes a negative temperatures, resulting in poor reliability converter for Aerospace applications. Unlike a regular Power Factor Pre-regulator (PFP), the proposed topology avoids the use of bulk energy storage capacitor which results in a fast transient response with enhanced reliability, reduced board real estate and weight. The proposed LED driver topology can control the LED current with both Buck and Boost mode of control, making it a good choice for applications with wide input voltage variation. A 110 W prototype based on proposed converter was built to verify the operation of proposed topology. The experimental results are in line with the predicted performance. The proposed converter is able to achieve a power factor of 0.988 with an input current THD of < 10%.

SOFTWARE: MATLAB/SIMULINK

 CONCLUSION:

This paper presents a novel LED driver topology, capable of input power factor correction, for space constrained applications, such as Aerospace exterior lighting product line. Due to the compact design of the proposed LED driver topology, it can be of great advantage for an integrated power supply solution for Aerospace exterior lighting product offerings. The proposed LED driver topology can control the LED current with both Buck and Boost mode of control, making it a good choice for applications with wide input voltage variation. The proposed LED driver topology has been verified by mathematical analysis, circuit simulation and performance has been demonstrated experimentally as well. The proposed LED driver topology promises an appreciable amount of savings in term of real estate, power loss, and heat sink requirements while enhancing the power density of the converter and its reliability. Typically, it’s the bulk output capacitor that wears out with pressure variation (wear out phenomenon accelerates at altitudes more than 8000m due to the reduced pressures); which can be avoided with the proposed topology. Depending upon the load (number of LEDs) and  input voltage; in order to protect LEDs, a reverse blocking diode may be required during the Buck operation. For Boost application, reverse blocking diode will not be required even with today’s technology. Authors have been granted a U.S. Patent 9363291 [8] against the propose novel LED driver topology.

REFERENCES:

[1] L. H. Dixon, "High Power Factor Preregulators for Off- Line Power Supplies," Unitrode Power Supply Design Seminar Manual SEM600, 1988. (Republished in subsequent Manuals)

[2] Spiazzi, G., and Mattavelli, P. (1994) “Design criteria for power factor preregulators based on SEPIC and Cuk converters in continuous conduction mode,” IEEE IAS Conference Record, 1994, 1084-1089.

[3] Z. Ye, F. Greenfeld, and Z. Liang, “Single-stage offline SEPIC converter with power factor correction to drive high brightness LEDs,” in Proc. IEEE Appl. Power Electron. Conf., 2009, pp. 546–553.

[4] C.Zhou and M.Jovanovic, "Design Trade-offs in Continuous Current-Mode Controlled Boost Power-Factor Correction Circuits", HFPC Cod. Proc., 1992, pp. 209-220

[5] L. H. Dixon, "Average Current Mode Control of Switching Power Supplies," Unitrode Power Supply Design Seminar Manual SEM700, 1990

 

Saturday, 13 March 2021

The Study of Single-phase PWM Rectifier Based on PR Control Strategy

 ABSTRACT:

Synchronous PI controller is usually used to track current in three-phase PWM rectifier with zero steady-state error which is difficult to achieve in the single-phase system. A novel proportional-resonant (PR) control scheme for single-phase PWM rectifier is proposed in the paper. Compared with traditional PI control and current hystereis control (CHC) methods, the PR control structure is simple and can reduce control time delay significantly. The simulation results verify the feasibility of the proposed control scheme in the disturbance rejection. In addition, sinusoidal current zero static error control can be achieved without a coordinate transformation and the DC voltage can automatically adjust to changes of grid voltage, load value and frequency which contributes to energy conversion and bidirectional flow of electricity.

KEYWORDS:

1.      Single-phase rectifiers

2.      CHC control

3.      PR-based control

SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

From the above conducted studies, one can conclude that PR-based Control strategy for single-phase PWM rectifier presents better steady-state and can successfully achieve accurate regulation with fast dynamic response with minimum harmonic distortions. The simulation results show that sinusoidal current zero static error control can be achieved without a coordinate transformation and the DC voltage could automatically adjust to changes of grid voltage, load value and frequency which contributes to energy conversion and bidirectional flow of electricity. The control algorithm is easy to be realized while the robustness and power quality is improved. The highlight of paper lies in applying PR regulator to the adjustment of sinusoidal AC current zero static error , building the system model of single-phase PWM rectifier in MATLAB/Simulink with CHC and PR control scheme respectively and giving proper comparisons to some degree.

 REFERENCES:

[1] Song H.S, Nam K, Instantaneous Phase-angle Estimation Algorithm Under Unbalanced Voltage-sag Condition, IEEE Proc Generation, Transmission, and Distribution, Vol.147, No.6, 409-415, 2000.

[2] Zmood D.N, Holmes D.G, Stationary Frame Current Regulation of PWM Inverters with Zero Steady-state Error, IEEE Transactions on Power Electronics, Vol.18, No.3, 814-822, 2003.

[3] Yuan X, Merk W, Stemmler H, Stationary-frame Generalized Integrators for Current Control of Active Power Filters with Zero Steady-state Error for Current Harmonics of Concern Under Unbalance and Distorted Operating Conditions, IEEE Trans on Industry Applications, Vol.38, No.2, 523-532, 2002.

 [4] ZHAO Qinglin, GUO Xiaoqiang, WU Weiyang, Research on Control Strategy for Single-phase Grid-connected Inverter, Proceedings of the CSEE, 60-64, 2007.

 [5] JIANG Jun-feng, LIU Hui-jin, CHEN Yun-ping, A Novel Double Hystersis Current Control Method of Active Power Filter with Voltage Space Vector. Proceedings of the CSEE, Vol.24, No.10, 82-86, 2004.

Sensor-Less Five-Level Packed U-Cell (PUC5) Inverter Operating in Stand-Alone and Grid-Connected Modes

ABSTRACT:

 In this paper a new mode of operation has been introduced for Packed U-Cell (PUC) inverter. A sensor-less voltage control based on redundant switching states is designed for the PUC5 inverter which is integrated into switching process. The sensor-less voltage control is in charge of fixing the DC capacitor voltage at half of the DC source value results in generating symmetric five-level voltage waveform at the output with low harmonic distortion. The sensor-less voltage regulator reduces the complexity of the control system which makes the proposed converter appealing for industrial applications. An external current controller has been applied for grid-connected application of the introduced sensor-less PUC5 to inject active and reactive power from inverter to the grid with arbitrary power factor while the PUC auxiliary DC bus is regulated only by sensor-less controller combined with new switching pattern. Experimental results obtained in stand-alone and grid-connected operating modes of proposed PUC5 inverter prove the fast response and good dynamic performance of the designed sensorless voltage control in balancing the DC capacitor voltage at desired level.

KEYWORDS:

1.      Multilevel Inverter

2.      Packed U-Cell

3.      Sensor-Less Voltage Regulator

4.      PUC5

5.      5-Level Inverter

6.      Power Quality

SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

The PUC5 inverter has been proposed in this paper while the capacitor voltage is balanced without involving any external controller and voltage feedback sensors. The proposed sensor-less voltage controller has been integrated into switching technique to work as open-loop system with reliable results. Moreover, another controller has been designed for the PUC5 inverter to work as unity power factor grid-connected inverter. Low harmonics components in both voltage and current waveforms generated by PUC5, no need to bulky output filters, reliable and good dynamic performance in variable conditions (including change in DC source, load, power amount injected to the grid), requiring no voltage/current sensor in stand-alone mode, low manufacturing costs and miniaturized package due to using less components and etc are interesting advantages of the introduced PUC5 topology which have been proved by experimental results in both stand-alone and grid-connected modes. The presented PUC5 inverter can be a challenging candidate for conventional photovoltaic application inverters.

REFERENCES:

[1] H. Abu-Rub, M. Malinowski, and K. Al-Haddad, Power electronics for renewable energy systems, transportation and industrial applications: John Wiley & Sons, 2014.

[2] L. G. Franquelo, J. Rodriguez, J. I. Leon, S. Kouro, R. Portillo, and M. A. M. Prats, "The age of multilevel converters arrives," IEEE Ind. Electron. Mag., vol. 2, no. 2, pp. 28-39, 2008.

 [3] C. Cecati, F. Ciancetta, and P. Siano, "A multilevel inverter for photovoltaic systems with fuzzy logic control," IEEE Trans. Ind. Electron., vol. 57, no. 12, pp. 4115-4125, 2010.

 [4] M. Seyedmahmoudian, S. Mekhilef, R. Rahmani, R. Yusof, and E. T. Renani, "Analytical modeling of partially shaded photovoltaic systems," Energies, vol. 6, no. 1, pp. 128-144, 2013. [5] H. Mortazavi, H. Mehrjerdi, M. Saad, S. Lefebvre, D. Asber, and L. Lenoir, "A Monitoring Technique for Reversed Power Flow Detection With High PV Penetration Level," IEEE Trans. Smart Grid, vol. 6, no. 5, pp. 2221-2232, 2015.

 

Real-Time Implementation of a Packed U-Cell Seven-Level Inverter with Low Switching Frequency Voltage Regulator

ABSTRACT:

 

In this paper a new cascaded nonlinear controller has been designed and implemented on the packed U-Cell (PUC) seven-level inverter. Proposed controller has been designed based on a simplified model of PUC inverter and consists of a voltage controller as outer loop and a current controller as inner loop. The outer loop regulates the PUC inverter capacitor voltage as the second DC bus. The inner loop is in charge of controlling the flowing current which is also used to charge and discharge that capacitor. The main goal of the whole system is to keep the DC capacitor voltage at a certain level results in generating a smooth and quasi-sine-wave 7-level voltage waveform at the output of the inverter with low switching frequency. The proposed controller performance is verified through experimental tests. Practical results prove the good dynamic performance of the controller in fixing the PUC capacitor voltage for various and variable load conditions and yet generating low harmonic 7-level voltage waveform to deliver power to the loads. Operation as an uninterruptible power supply (UPS) or AC loads interface for photovoltaic energy conversion applications is targeted.

KEYWORDS:

1.      Packed U-Cell

2.      Multilevel Inverter

3.      Voltage Balancing

4.      Nonlinear Controller

5.      Renewable energy conversion

 SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

In this paper a new cascaded nonlinear controller has been designed for 7-level PUC inverter based on the simple model derived by multilevel inverter topology concept. Experimental results showed appropriate dynamic performance of the proposed controller in stand-alone mode as UPS, renewable energy conversion system or motor drive applications. Different changes in the load and DC bus voltage have been made intentionally during the tests to challenge the controller

reaction in tracking the voltage and current references. Proposed controller demonstrated satisfying performance in fixing the capacitor voltage of the PUC inverter, generating seven-level voltage with low harmonic content at the output of the PUC inverter and ensures low switching frequency operation of those switches. By applying the designed controller on the 7-level PUC inverter it can be promised to have a multilevel converter with maximum voltage levels while using less active switches and DC sources aims at manufacturing a low-cost converter with high efficiency, low switching frequency, low power losses and also low harmonic contents without using any additional bulky filters

REFERENCES:

[1] H. Abu-Rub, M. Malinowski, and K. Al-Haddad, Power electronics for renewable energy systems, transportation and industrial applications: John Wiley & Sons, 2014.

[2] J. M. Carrasco, L. G. Franquelo, J. T. Bialasiewicz, E. Galván, R. P. Guisado, M. A. Prats, et al., "Power-electronic systems for the grid integration of renewable energy sources: A survey," IEEE Trans. Ind. Electron., vol. 53, no. 4, pp. 1002-1016, 2006.

[3] M. Mobarrez, M. G. Kashani, G. Chavan, and S. Bhattacharya, "A Novel Control Approach for Protection of Multi-Terminal VSC based HVDC Transmission System against DC Faults," in ECCE 2015- Energy Conversion Congress & Exposition, Canada, 2015, pp. 4208- 4213.

[4] B. Singh, A. Chandra, and K. Al-Haddad, Power Quality: Problems and Mitigation Techniques: John Wiley & Sons, 2014.

[5] B. Singh, K. Al-Haddad, and A. Chandra, "A review of active filters for power quality improvement," IEEE Trans. Ind. Electron., vol. 46, no. 5, pp. 960-971, 1999

 

Front-End Buck Rectifier with Reduced Filter Size and Single-Loop Control

ABSTRACT:

This paper presents a transformerless solution for front-end rectification, which is particularly suitable for traction applications, requiring high voltages to be stepped down to appropriate dc voltage. The proposed topology is based on pulse width modulation buck rectifier (current source inverter topology) and is capable of rectification and stepping down of single-phase ac supply, in a single stage. A new control scheme is proposed to achieve constant dc output voltage and sinusoidal source current, irrespective of large ripples in the dc inductor current. The proposed scheme is configured in single-loop voltage control mode. The relevant small-signal model is derived from the large-signal model using multi order decomposition. An elaborate procedure of dc filter design is discussed, for circuit operation with minimum energy storage. All analytical results are validated by numerical simulation for sinusoidal and distorted source voltage. Experimental verification is achieved through a 1.2-kW grid-connected laboratory prototype.

KEYWORDS:

1.      Buck rectifier (BR)

2.      Single-loop control

3.      Single phase

4.      Traction

5.      Transformerless

SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

In this paper, a single-loop control scheme for single-phase BR has been presented. A nonlinear modulation scheme is proposed, and its effect is analyzed using a multi order system decomposition. The effectiveness of the proposed scheme is proved by simulation and experimental results. From experimental results, it is clear that the proposed control scheme is capable of maintaining sinusoidal source current and near-UPF operation with optimum filter volume, even under distorted grid conditions. Generalized design of the dc inductor, which is the most critical element, is presented in detail. Since source current wave shape is maintained despite ripples in dc current, requirement of an inner current loop is rendered superfluous. Apart from justifying the single-loop control scheme, this also entails greatly simplified controller design and realization.

REFERENCES:

[1] M. Brenna, F. Foiadelli, and D. Zaninelli, “New stability analysis for tuning PI controller of power converters in railway application,” IEEE Trans. Ind. Electron., vol. 58, no. 2, pp. 553–543, Feb. 2011.

[2] M. Carpita, M. Marchesoni, M. Pellerin, and D. Moser, “Multilevel converter for traction applications: Small-scale prototype test results,” IEEE Trans. Ind. Electron., vol. 55, no. 5, pp. 2203–2212, May 2008.

[3] P. Drabek, Z. Peroutka, M. Pitterman, and M. Cedl, “New configuration of traction converter with medium-frequency transformer using matrix converters,” IEEE Trans. Ind. Electron., vol. 58, no. 11, pp. 5041–5048, Nov. 2011.

[4] A. Rufer, N. Schibli, C. Chabert, and C. Zimmermann, “Configurable front-end converters for multicurrent locomotives operated on 16 2/3 Hz and 3 kV DC systems,” IEEE Trans. Power Electron., vol. 18, no. 5, pp. 1186–1193, Sep. 2003.

                                                                                                  

[5] S. Dieckerhoff, S. Bernet, and D. Krug, “Power loss-oriented evaluation of high voltage IGBTs and multilevel converters in transformerless traction applications,” IEEE Trans. Power Electron., vol. 20, no. 6, pp. 1328–1336, Nov. 2005

Monday, 8 March 2021

Initial Rotor Position Detection for Brushless DC Motors Based on Coupling Injection of High-Frequency Signal

ABSTRACT:

 In applications where motor inversion is forbidden, it is important to detect the initial rotor position of the motor. For this reason, based on coupling injection of high-frequency signal, a novel method of initial rotor position detection for brushless DC motors (BLDCM) is proposed in this paper. Firstly, the proposed method detects the relationship between three-phase winding inductances by injecting the high frequency detection signal into motor windings in a coupling way, and the initial rotor position is determined into two sectors with 180 degrees electric angle difference. Then, the polarity of the permanent magnet rotor is determined by applying two opposite voltage vectors to motor windings, so that the initial rotor position is determined into a unique sector, and the positioning accuracy is 30 degrees electric angle. The proposed method significantly reduces the amplitude of the detection signal while increases its frequency by the way of coupling injection, thus reducing the response current and electromagnetic torque generated by the high-frequency signal and reducing the possibility of rotor inversion. Finally, the effectiveness of the proposed method is verified by experimental results.

KEYWORDS:

1.      Brushless DC motor

2.      Initial rotor position

3.      High-frequency signal

4.      Coupling injection

SOFTWARE:MATLAB/SIMULINK

 CONCLUSION:

In this paper, the relationship between winding inductances and the rotor position of BLDCM is analyzed in detail, and a novel method of initial rotor position detection based on high-frequency signal coupling injection is proposed. The initial rotor position can be determined into a sector with 30 degrees electric angle. The proposed method overcomes the limitations of fixed DC-link voltage and limited switching frequency of the inverter by the way of coupling injection, and significantly reduces the amplitude of the detection signal while increases its frequency. Experimental results show that, compared with traditional methods, the method proposed in this paper can accurately detect the initial rotor position and effectively reduce the electromagnetic torque, thus reducing the possibility of rotor inversion in the process of initial position detection.

REFERENCES:

[1] K. Liu, Z. Zhou and W. Hua, “A Novel Region-Refinement Pulse Width Modulation Method for Torque Ripple Reduction of Brushless DC Motors,” IEEE Access, vol. 7, pp. 5333-5342, Dec. 2019, DOI. 10.1109/ACCESS.2018.2888630.

[2] C. L. Xia, G. K. Jiang, W. Chen and T. N. Shi, “Switching-Gain Adaptation Current Control for Brushless DC Motors,” IEEE Trans. Ind. Electron., vol. 63, no. 4, pp. 2044–2052, Apr. 2016, DOI. 10.1109/TIE.2015.2506144.

[3] C. L. Xia, Y. F. Wang, and T. N. Shi, “Implementation of finite-state model predictive control for commutation torque ripple minimization of permanent-magnet brushless DC motor,” IEEE Trans. Ind. Electron., vol.60, no.3, pp. 896–905, Mar. 2013, DOI. 10.1109/TIE.2012.2189536.

[4] B. Tan, X. Wang, D. Zhao, K. Shen, J. Zhao and X. Ding, “A Lag Angle Compensation Strategy of Phase Current for High-Speed BLDC Motors,” IEEE Access, vol. 7, pp. 9566-9574, Dec. 2019, DIO. 10.1109/ACCESS.2018.2887106.

[5] J. Shao, “An improved microcontroller-based sensorless brushless DC (BLDC) motor drive for automotive applications,” IEEE Trans. Ind. Appl., vol. 42, no. 5, pp. 1216–1221, Sep. 2006, DOI. 10.1109/TIA.2006.880888

A New Five-Level Buck-Boost Active Rectifier

 ABSTRACT:

 In this paper a new single-phase five-level buck boost active rectifier is introduced called capacitor tied switches (CTS). The proposed rectifier has two independent DC outputs that can be connected to two different loads. Different switching  states and the average mode of the proposed topology are analyzed to design the associated controller aims at regulating the two output DC voltages, generating five-level voltage at the input of the rectifier and finally draw unity power factor and sinusoidal current from AC grid. From AC grid view, the rectifier works in boost mode however the generated DC voltage can be split into two separate outputs which may be less than the AC peak voltage or even more leads to work in both buck and boost operation mode. Full simulation results are shown and analyzed to validate the effective operation and good dynamic performance of the proposed five-level buck-boost rectifier.

KEYWORDS:

1.      Multilevel converter

2.      Packed U-Cell

3.      Active PFC rectifier

4.      Buck-boost rectifier

5.      Capacitor Tied Switches (CTS).

SOFTWARE:MATLAB/SIMULINK

CONCLUSION:

In this paper a new topology of buck-boost active rectifier has been introduced based on slight modification of the third U-cell of the PUC original design. The proposed rectifier called CTS includes six switches tied by two capacitors as two output independent DC terminals and generates five-level voltage waveform at the input. The latter draw low harmonic current in-phase with the grid voltage making the operation at unity power factor rectifier easy in both buck and boost mode. This topology does not need additional bulky filters while switching at low frequency which constitute a big advantage of the presented CTS rectifier. Simulation results including regulated DC voltages, high power factor, and low supply THD current mainly obtained by the five-level rectifier input voltage. Moreover, good dynamic performance, fast response and reliable operation of the implemented controller and CTS converter topology were proven and discussed in details.

REFERENCES:

[1] B. Singh, B. N. Singh, A. Chandra, K. Al-Haddad, A. Pandey, and D. P. Kothari, "A review of single-phase improved power quality ACDC converters," Industrial Electronics, IEEE Transactions on, vol. 50, pp. 962-981, 2003.

[2] B. Singh, B. N. Singh, A. Chandra, K. Al-Haddad, A. Pandey, and D. P. Kothari, "A review of three-phase improved power quality AC-DC converters," Industrial Electronics, IEEE Transactions on, vol. 51, pp. 641-660, 2004.

[3] H. Abu-Rub, M. Malinowski, and K. Al-Haddad, Power electronics for renewable energy systems, transportation and industrial applications: John Wiley & Sons, 2014.

[4] L. Yacoubi, K. Al-Haddad, L.-A. Dessaint, and F. Fnaiech, "Linear and nonlinear control techniques for a three-phase three-level NPC boost rectifier," Industrial Electronics, IEEE Transactions on, vol. 53, pp. 1908-1918, 2006.

[5] L. Yacoubi, K. Al-Haddad, L.-A. Dessaint, and F. Fnaiech, "A DSPbased implementation of a nonlinear model reference adaptive control for a three-phase three-level NPC boost rectifier prototype," Power Electronics, IEEE Transactions on, vol. 20, pp. 1084-1092, 2005.