A Novel Design of Hybrid Energy Storage System for Electric Vehicles

ABSTRACT:  

In order to provide long distance endurance and ensure the minimization of a cost function for electric vehicles, a new hybrid energy storage system for electric vehicle is designed in this paper. For the hybrid energy storage system, the paper proposes an optimal control algorithm designed using a Li-ion battery power dynamic limitation rule-based control based on the SOC of the super-capacitor. At the same time, the magnetic integration technology adding a second-order Bessel low-pass filter is introduced to DC-DC converters of electric vehicles. As a result, the size of battery is reduced, and the power quality of the hybrid energy storage system is optimized. Finally, the effectiveness of the proposed method is validated by simulation and experiment.

KEYWORDS:

1.      Hybrid energy storage system

2.      Integrated magnetic structure

3.      Electric vehicles

4.      DC-DC converter

5.      Power dynamic limitation

SOFTWARE: MATLAB/SIMULINK

 CIRCUIT DIAGRAM:

Fig.1 Topology of the hybrid energy storage system

EXPECTED SIMULATION RESULTS:

(a) Power command and actual power

(b) Power of the super-capacitor and Li-ion battery

Fig.2 Simulation results of the proposed HESS

(a)     Battery current

(b)     Super-capacitor current

(c)     Load current

(d)     Load voltage

Fig.3 Simulation results of the proposed HESS applied on electric vehicles

CONCLUSION:

In this paper, a new hybrid energy storage system for electric vehicles is designed based on a Li-ion battery power dynamic limitation rule-based HESS energy management and a new bi-directional DC/DC converter. The system is compared to traditional hybrid energy storage system, showing it has significant advantage of reduced volume and weight. Moreover, the ripple of output current is reduced and the life of battery is improved.

REFERENCES:

[1] Zhikang Shuai, Chao Shen, Xin Yin, Xuan Liu, John Shen, “Fault analysis of inverter-interfaced distributed generators with different control schemes,” IEEE Transactions on Power Delivery, DOI: 10. 1109/TPWRD. 2017. 2717388.

[2] Zhikang Shuai, Yingyun Sun, Z. John Shen, Wei Tian, Chunming Tu, Yan Li, Xin Yin, “Microgrid stability: classification and a  review,” Renewable and Sustainable Energy Reviews, vol.58, pp. 167-179, Feb. 2016.

[3] N. R. Tummuru, M. K. Mishra, and S. Srinivas, “Dynamic energy management of renewable grid integrated hybrid  energy storage system, ” IEEE Trans. Ind. Electron., vol. 62, no. 12, pp. 7728-7737, Dec. 2015.

[4] T. Mesbahi, N. Rizoug, F. Khenfri, P. Bartholomeus, and P. Le Moigne, “Dynamical modelling and emulation of Li-ion batteries- supercapacitors hybrid power supply for electric vehicle applications, ” IET Electr. Syst. Transp., vol.7, no.2, pp. 161-169, Nov. 2016.

[5] A. Santucci, A. Sorniotti, and C. Lekakou, “Power split strategies for hybrid energy storage systems for vehicular applications, ” J. Power Sources, vol. 258, no.14, pp. 395-407,  2014.

New Three-Phase Symmetrical MultilevelVoltage Source Inverter

ABSTRACT:  

This paper presents a new design and implementation of a three-phase multilevel inverter (MLI) for distributed power generation system using low frequency modulation and sinusoidal pulse width modulation (SPWM) as well. It is a modular type and it can be extended for extra number of output voltage levels by adding additional modular stages. The impact of the proposed topology is its proficiency to maximize the number of voltage levels using a reduced number of isolated dc voltage sources and electronic switches. Moreover, this paper proposes a significant factor (F_C/L), which is developed to define the number of the required components per pole voltage level. A detailed comparison based on (F_C/L) is provided in order to categorize the different topologies of the MLIs addressed in the literature. In addition, a prototype has been developed and tested for various modulation indexes to verify the control technique and performance of the topology. Experimental results show a well-matching and good similarity with the simulation results.

KEYWORDS:

1.      Low frequency modulation

2.      Multi-level inverter

3.      Multi-level inverter comparison factor

4.      Sinusoidal pulse-width modulation (SPWM)

5.      Symmetrical DC power sources

6.      Three-phase

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig. 1. Proposed three-phase MLI topology.

EXPECTED SIMULATION RESULTS:

Fig. 2. Output line-to-line voltages ( V_AB,V_BC , and V_CA ) with low frequency (50 Hz) modulation technique. (a) Simulation.

Fig. 3. Output phase voltages ( V_AN,V_BN , and V_CN ) with low frequency modulation technique. (a) Simulation.

Fig. 4. Inverter outputs with R-L load (V_AB ,V_AN , and I_AN) with low frequency modulation technique. (a) Simulation.

Fig. 5. Pole voltages for scheme I, m_i =0.95 and f_s=2.5kHz. (a) Simulation.

Fig. 6. Line-to-line voltages for scheme I, m_i =0.95 and f_s=2.5kHz . (a) Simulation.

Fig. 7. Phase voltages for scheme I, m_i =0.95 and f_s=2.5kHz . (a) Simulation.

Fig. 8. Pole voltages for scheme II, m_i =0.95 and f_s=2.5kHz . (a) Simulation.

Fig. 9. Line-to-line voltages for scheme II, m_i =0.95 and f_s=2.5kHz  . (a) Simulation.

Fig. 10. Phase voltages for scheme II, m_i =0.95 and f_s=2.5kHz. (a) Simulation.

Fig. 11. Line-to-line voltage and phase voltage at for scheme I, m_i =0.95 and f_s=2.5kHz . (a) Simulation.

Fig. 12. Line-to-line voltage and phase voltage for scheme II, m_i =0.95 and f_s=2.5kHz . (a) Simulation.

Fig. 13. Inverter output voltages: (a) three phase line-to-line voltages ( V_AB, V_BC, and V_CA ), (b) line-to-line voltage, phase voltage and the phase current under R-L load.

CONCLUSION:

A new modular multilevel inverter topology using two modulation control techniques is presented. The proposed has several advantages compared with existing topologies. A lower number of components count such as isolated dc-power supplies, switching devices, electrolyte capacitors, and power diodes are required. So it exhibits the merits of high efficiency, lower cost, simplified control algorithm, smaller inverter's foot print and increased the overall system reliability. Due to the modularity of the presented topology, it can be extended to higher stages number leads to a good performance issues such as low, low, and low and eliminating the output filter will be obtained. Beside the low frequency modulation, two schemes are successfully applied to control the suggested . This paper also suggests a significant factor, which defines the required components to generate one voltage level across the output pole terminals. The issue related to the cost of each used component is out of scope of this paper. The system simulation model and its control algorithm are developed using PSIM and MATLAB software package tools to validate the proposed topology. A laboratory prototype has been developed and tested for various modulation indexes to verify the control techniques and performance of the topology, the similarity between the simulation and obtained experimental results was confirmed.

REFERENCES:

[1] S. J. Park, F. S. Kang, M. H. Lee, and C. U. Kim, “A new single-phase five-level PWM inverter employing a deadbeat control scheme,” IEEE Trans. Power Electron., vol. 18, no. 3, pp. 831–843, May 2003.

[2] V. G. Agelidis, D. M. Baker, W. B. Lawrance, and C. V. Nayar, “A multilevel PWM inverter topology for photovoltaic applications,” in Proc. Int. Symp. Ind. Electron., Jul. 1997, vol. 2, pp. 589–594.

[3] G. J. Su, “Multilevel DC-link inverter,” IEEE Trans. Ind. Appl., vol. 41, no. 3, pp. 848–854, May–Jun. 2005.

[4] M. Calais, L. J. Borle, and V. G. Agelidis, “Analysis of multicarrier PWM methods for a single-phase five level inverter,” in Proc. Power Electron. Specialists Conf., 2001, vol. 3, pp. 1351–1356.

[5] C. T. Pan, C. M. Lai, and Y. L. Juan, “Output current ripple-free PWM inverters,” IEEE Trans. Circuits Syst. II, Exp. Briefs., vol. 57, no. 10, pp. 823–827, Oct. 2010.

An Efficient Constant Current Controller for PV Solar Power Generator Integrated with the Grid

ABSTRACT:  

This paper presents the detailed design and modeling of grid integrated with the Photovoltaic Solar Power Generator. As the Photovoltaic System uses the solar energy as one of the renewable energies for the electrical energy production has an enormous potential. The PV system is developing very rapidly as compared to its counterparts of the renewable energies. The DC voltage generated by the PV system is boosted by the DC-DC Boost converter. The utility grid is incorporated with the PV Solar Power Generator through the 3-ı PWM DC-AC inverter, whose control is provided by a constant current controller. This controller uses a 3-ı phase locked loop (PLL) for tracking the phase angle of the utility grid and reacts fast enough to the changes in load or grid connection states, as a result, it seems to be efficient in supplying to load the constant voltage without phase jump. The complete mathematical model for the grid connected PV system is developed and simulated. The results verify that the proposed system is proficient to supply the local loads.

KEYWORDS:

1.      PV Solar Power Generator

2.      DC-DC Boost Converter

3.      PWM inverter

4.      PLL

5.      Constant Current Controller (CCC)

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig.1 Switching Model of Solar Inverter

EXPECTED SIMULATION RESULTS:

Fig.2 P-V Curve of the Solar Array

Fig. 3 V-I Curve of the Solar Array

Fig. 4 DC voltage delivered by the Boost converter

Fig. 5Inverter output voltage before filtering

Fig. 6 Inverter output voltage after filtering

Fig. 7 Load current for supplying the 2 MW load.

Fig.8 Load current for supplying the load of about 30 MW, 2 MVAr

CONCLUSION:

For improving the energy efficiency and power quality issues with the increment of the world energy demand, the power generation using the renewable energy source is the only solution. There are several countries located in the tropical and temperature regions, where the direct solar density may reach up to 1000W/m2. Hence PV system is considered as a primary resource. In this paper, the detailed modeling of grid connected PV generation system is developed. The DC-DC boost converter is used to optimize the PV array output with the closed loop control for keeping the DC bus voltage to be constant. The 2 level 3-phase inverter is converting the DC into the sinusoidal AC voltage. The control of the solar inverter is provided through the constant current controller. This controller tracks the phase and frequency of the utility grid voltage using the Phase- Locked-Loop (PLL) system and generates the switching pulses for the solar inverter. Using this controller the output voltage of the solar inverter and the grid voltage are in phase. Thus the PV system can be integrated to the grid. The simulation results the presented in this paper to validate the grid connected PV system model and the applied control scheme.

REFERENCES:

[1] A. M. Hava, T. A. Lipo and W. L. Erdman. “Utility interface issues for line connected PWM voltage source converters: a comparative study”, Proceeding of APEC’95, Dallas (USA), pp. 125-132, March 1995.

[2] L. J. BORLE, M. S. DYMOND and C. V. NAYAR, “Development and testing of a 20 kW grid interactive photovoltaic power conditioning system in Western Australia”, IEEE Transaction, Vol. 33, No. 2, pp. 502-508, 1997.

[3] M. Calais, J. Myrzik, T. Spooner, V. Agelidis, “Inverters for single- phase grid connected photovoltaic systems – an overview”, IEEE 33rd Annual Power Electronics Specialists Conference, Volume 4, 23-27 June 2002

[4] S. K. Chung, “Phase-Locked Loop for Grid connected Three-phase Power Conversion Systems”, IEE Proceeding on Electronic Power Application, Vol. 147, No. 3, pp. 213-219, 2000.

[5] S. Rahman, “Going green: the growth of renewable energy”, IEEE Power and Energy Magazine, 16-18 Nov./Dec. 2003.