IOSR Journal of Engineering (IOSRJEN) e-ISSN: 2250-3021, p-ISSN: 2278-8719 Vol. 3, Issue 10 (October. 2013), ||V4|| PP 30-37 www.iosrjen.org 30 | P a g e Transformer Less Boost DC-DC Converter with Photovoltaic Array G.Neelakrishnan, M.Kannan, S.Selvaraju, K.Vijayraj, M.Balaji, D.Kalidass 1 (AP/EEE, Muthayammal college of Engineering) 2 (AP/EEE, Muthayammal college of Engineering) 3 (AP/ECE, Muthayammal college of Engineering) 4 (AP/ECE, Muthayammal college of Engineering) 5 (AP/ECE, Muthayammal college of Engineering) 6 (AP/EEE, Muthayammal college of Engineering) Abstract: - Nowadays, transformer less converters are preferred for higher efficiency, low size and cost. The output voltage of PV arrays is relatively low, requiring a high step-up converter to obtain the DC voltage input of the inverter, the performance and effectiveness of some standard and improved boost converter circuits are discussed and compared in terms of voltage gain, power loss and switch voltage stress requirement. In fact, those performances are examined with deriving formulas and equations of current, voltages, power loss and voltage gain. Keywords: - Transformer less, Boost converter, PV Array,; simulation for Transformrer less Boost converter; open loop and closed loop. I. INTRODUCTION The DC to DC or boost converter is the front-end component connected between the PV array and the load. The conventional Isolation Two transistor has additionally, the magnitude if Ringing is not easily predictable during the design stage. The Ringing also increases the voltage stress of primary winding of the Transformer. As a result, the conversion efficiency is degraded and the electromagnetic interference problem becomes severe under this situation. To increase the conversion efficiency, many modified step-up converter topologies have been investigated by several researchers. The output of the FC or PV cells is typically an unregulated low-level DC voltage that needs to be stepped up to a regulated higher level, for many potential practical applications, and boost converter stages are employed for this purpose. In many applications, the use of a transformer can provide increased output/input voltage gain, as required. However, there are a number of applications where transformer-less power electronic energy converter systems could potentially offer significant advantages, including cost and converter size reduction. the installation of PV generation systems is rapidly growing due to concerns related to environment, global warming, energy security, technology improvements and decreasing costs. PV generation system is considered as a clean and environmentally-friendly source of energy. The main applications of PV systems are in either standalone or grid connected configurations. Standalone PV generation systems are attractive as indispensable electricity source for remote areas. However, PV generation systems have two major problems which are related to low conversion efficiency of about 9% to 12 % especially in low irradiation conditions and the variation of amount of electric power generated by PV arrays continuously with weather conditions. Therefore, research works are carried out to increase the efficiency of the energy produced from the PV arrays. In fact, this converter uses two inductors of the same inductance level, and the two switches being simultaneously . Similarly to the other converter circuits, the operation of such a converter is subdivided into two modes; the CCM and the DCM. For an CCM, the switches S1 and S2and are both turned on, and the equivalent circuit of the converter. During this stage, inductors and are charged in parallel from the DC source where as the capacitor releases its energy to the load. Moreover, capacitors and are charged from the DC source. For an DCM, the switches and are turned off, the inductors L1 and L2 and capacitors C1 and C2 are series connected with the DC source in order to transfer the stored energy to the capacitor and the load.The benefit of choosing the PWM over analog control is increased noise immunity which the PWM is sometimes used for communication. Switching from an analog signal to PWM can increase the length of a communications channel dramatically. At the receiving end, a suitable RC (resistor-capacitor) or LC (inductor capacitor) network can remove the modulating high frequency square wave and return the signal to analog form. So, the filter requirement can be reduced and the overall inverter size can be reduced. II. CONVENTIONAL ISOLATION ZETA CONVERTER TOPOLOGY Semiconductor devices is based on the maximum values of the voltage and current stresses withstood by the switches and the diodes. The magnetic and static components are selected as follows. The main drawback