Quadratic boost converter with low-output voltage ripple

Abstract

This study proposes a non-isolated quadratic boost converter (QBC) that features a low-output-voltage ripple with respect to traditional QBCs. This advantage is in contrast with other topologies that require a higher amount of stored energy by capacitors to achieve the same output-voltage ripple specification. This benefit permits to design a compact converter, since the size of capacitors is proportional to their energy storage rating. Moreover, the proposed transformerless topology is suitable for applications that require high-voltage gains as in the case of renewable energy applications. The main properties of the converter are corroborated as well as its advantages by providing mathematical models, analytical waveforms and experiments.

Block Diagram:

 

Fig. 1  Traditional QBC

(a) Single switch QBC, quadratic boost converter [8–12], (b) Emerging QBC with

reduced energy stored, reduced energy-stored quadratic boost converter in [14, 15]

 

Expected Simulation Results:

Fig. 2  Experimental waveforms

(a) Currents through inductors and voltages across switches S1 and S2, (b) Output voltage and voltages across capacitors C1 and C2 with respect to the PWM signal, (c) Output voltage and voltages across capacitors C1 and C2 in AC mode, with respect to the PWM signal of switch with Vg = 90 V and D = 0.4

Fig. 3  Experimental waveforms

(a) Currents through inductors and voltages across switches S1 and S2, (b) Output voltage and voltages across capacitors C1 and C2 with respect to the PWM signal, (c) Output voltage and voltages across capacitors C1 and C2 in AC mode, with respect to the PWM signal of switch with Vg = 62 V and D = 0.5

 

Fig. 4  Experimental waveforms

(a)     Currents through inductors and voltages across switches S1 and S2, (b) Output voltage and voltages across capacitors C1 and C2 with respect to the PWM signal, (c) Output voltage and voltages across capacitors C1 and C2 in AC mode, with respect to the PWM signal of switch with Vg = 40 V and D = 0.6

Conclusions

 

In this paper, a novel quadratic dc–dc converter topology is presented. The main advantages of the proposed topology are: (i) the voltage gain is quadratic type, which enables the converter to work in a wide input voltage range within a reduced range of duty cycle. (ii) A voltage ripple cancelling technique can be applied to the output voltage, and then for the same energy stored in capacitors, the output-voltage ripple is smaller than existing topologies; this allows using smaller capacitors for the same voltage ripple specification. Several tests were performed over the full operation range, defined with a realistic example. Experimental results showed that the proposed converter produces a lower voltage ripple in the full operation range compared with traditional topologies. The previous propositions are demonstrated using analytical formulations and waveforms as well as by experimental results.

References

 

[1] Lessa Tofoli, F., de Castro Pereira, D., de Paula, W.J., et al.: ‘Survey on nonisolated high-voltage step-up dc–dc topologies based on the boost converter’, IET Power Electron, 2015, 8, (10), pp. 2044–2057

 

	[2] Erickson, R.W., Maksimovic, D.: ‘Fundamentals of power electronics’ (Springer, New York, USA, 2001, 2nd edn.) [3] Rosas-Caro, J.C., Ramirez, J.M., Peng, F.Z., et al.: ‘A DC–DC multilevel boost converter’, IET Power Electron, 2010, 3, (1), pp. 129–137 [4] Gandomkar, A., Parastar, A., Seok, J.: ‘High-power multilevel step-up DC/DC converter for offshore wind energy systems’, IEEE Trans. Ind. Electron., 2016, 63, (12), pp. 7574–7585 [5] Rosas-Caro, J.C., Mancilla-David, F., Mayo-Maldonado, J.C., et al.: ‘A                   transformerless high-gain boost converter with input current ripple cancelation at a selectable duty cycle’, IEEE Trans. Ind. Electron., 2013, 60, (10), pp. 4492–4499