# A Voltage Multiplier Circuit Based Quadratic Boost Converter for Energy Storage Application
## 1 Introduction
High gain and low stress across capacitors and continuous input current are desirable features required in the dc-dc converter [17; 18] used in fuel cell and electric vehicle applications. Interleaved boost converters [19; 20; 21] are derived from H- bridge structures and have very low voltages stress across devices. The input current drawn from the source is also very small; however, these structures need multiple VMCs to increase the voltage to desirable limits. In some interleaved structures, the number of components may increase to obtain high voltage at the output. Z-source dc-dc converters can be employed to get continuous input current with reduced voltage stress [22; 23] with moderate voltage gain. The parasitic resistance of the inductor influences the voltage gain and efficiency of the converter. The higher the value of parasitic resistance, the lower the voltage gain and losses will increase, resulting in a drop of efficiency at higher [24] duty ratios. Some other new dc-dc converter structures with high voltage gain are proposed in [25; 26]. Quadratic boost converters provide high voltage gain, especially at low duty ratios. The non-isolated configurations of these structures do not use any transformer and are suitable in solar PV applications for medium power applications. The voltage stress across switch, diodes, and capacitors is generally low in these structures, which is another advantage apart from high-gain; however, the number of components may increase [27; 28; 29; 30] if a very high quadratic gain is required. The paper's main contribution is the proposed new dc-dc converter with desirable characteristics like high voltage gain with a reduced number of components, low voltage stress on switching devices, and continuous input current. Further, the proposed converter has a quadratic gain, which is achieved by using only two inductors. It is to be noted that a smaller number of inductors in the circuit makes the circuit less bulky. The other key feature of the proposed converter is that the duty ratio can be changed widely to obtain the desired output voltage which is not possible in Z-source type of converters [22; 23]. The main advantages of the proposed topology are as follows:1. The voltage gain is higher than the conventional quadratic boost converter (CQBC) [18], and twice the quadratic boost converter (TCQBC) proposed in [30]. The voltage gain of more than 10 times can be achieved for the duty of less than 0.5. 2. The voltage stress across switches of the proposed converter is much less than the output voltage V\({}_{\text{o}}\), which is an improvement over the quadratic converters proposed in [18; 30] in which the voltage stress is equal to V\({}_{\text{o}}\). Moreover, the diodes and capacitors also have low voltage stress, leading to the selection of low voltage rating devices and subsequently improving the converter's efficiency. 3. To achieve this high voltage gain, the coupled inductor is not used, and hence the problem of leakage inductance and the need for a snubber circuit is avoided. 4. The input current is continuous, which is another significant advantage of the proposed topology. 5. The control of the proposed converter is easy, as two switches are turned ON and OFF simultaneously. In Section 2 the structure and working of the proposed converter is discussed. In Section 3 losses in the converter and non-ideal gain of the converter are shown. In Section 4 comparison of the proposed converter with other converters are shown. In Sections 5 and 6, hardware results and conclusions are discussed.