New Concept Note on Affordable Efficient Energy Utilization with Right Selection of Reliable Solar Converters for Household Loads

This paper presents a detailed description of three methodologies to electrify the rural households of small loads with reliable and economical method using solar energy as input source of power. It is observed that high DC voltage is better and economical solution rather than AC based solar systems and low voltage DC systems. In this paper, three methodologies were analysed to select the right combination of portable converters with low prices, which may further enhance the energy access and affordability to common people. The proposed three methodologies were tested through action research in collaboration with a team of scientists and technical experts of National Institute of Solar Energy. The comparative analysis is carried out on three different converters, various kind of house loads and types of power supply i.e. AC/DC. The performance, quality and economic evaluation has been carried out with the help of MATLAB SIMULINK and other measuring instruments specific for solar photovoltaic systems. The derived results were analysed and inferences made for use in village household loads and their income groups. Further, a three-step analytical framework on village-level power energy efficient power at affordable power preposition was presented. This study will help in the designing as well as in the performance and economic evaluation of converters based on solar photovoltaic systems of different technologies.

1 Introduction: The cumulative imbalance in atmosphere due to consumption of non-renewable energy sources which continuously leads to environmental degradation and therefore, the researchers investigate environment friendly and clean renewable energy resources. Solar energy is becoming progressively important and now established for various technologies, which is responsible for appropriate selections to electricity users to receive power from the grid source and can supply power to grid in order to achieve individual user demands and alternatively to be a power producer as they can easily supply extra power to grid as well by the concept of grid fed. Solar power converters are unique in design and cost effective renewable energy resource. Solar power converters, being able to convert the energy direct coming from sun through solar photovoltaic modules convert into electrical energy using various conversion approaches. Understanding the concept of electronics devices such as diode and transistors and also the voltage and current relationship for linear devices [1], [2].
Improvements in high voltage gain DC-DC converter [3] to attain high efficiency and output power.
[4], [5], [6]. Study of different technologies of transformer-less converters through high step up voltage gain, steady analysis and detailed discussion on boundary operating conditions [7], [8]. The solar power converters proposed the features of light weight, lesser cost, easy and noiseless operation which results in improved life, better reliability and less maintenance [9]. The lack of presence of experimental values on total power consumption with comparative analysis of different technologies of solar power converters motivates the researchers to work more. Therefore, the principle operation of the circuit is to control the strategies and features of overall system. Study their characteristics in detail as simulation and experimental outcomes are presented to validate hypothetical investigation [10].
Research efforts in components and behavioural analysis of different technologies of DC-DC converters like sepic, flyback and cuk in order to increase the efficiency are underway [11], [12], [13], [14], and [15].
By analysing the circuit geometry of power converters comes under the approach of improving the performance of existing converters. The DC-DC boost converter and ZVS & ZCS operation have been investigated by many researchers [16], [17][18][19][20][21][22][23][24]. Bascope, et al. [25] analysed the performance of different topologies of DC-DC converters i.e. buck, boost, buck-boost, cuk, sepic and zeta then proposed a new converter with high power and low current ripple. However, the proposed design of the circuit is more complex. Kim et al. [26] proposed the development in designing of the coupled inductor using ideal coupling coefficient in order to attain the reduced ripple current. Therefore, to discover the optimal coupling coefficient, inductor (L1, L2) current ripple by analysing the optimal circuit. Yang and He [27] presented a solar photovoltaic system with high efficiency connected with utility grid. The suggested  [34], [35] and [36], at high output voltage applications switching power losses occur [37]. However, these studies do not consider the quality and performance evaluation using international standard [38] and cost analysis according to Indian households. In the present study, high power converter practice is used to improve output voltage of the 12 V input dc source to dc interface system towards the utility grid source through DC to AC conversion system. Distinct solar photovoltaic module [39] using fuel cell energy conversion method [40], [41] and [42] are predominantly low voltage source applications and therefore high voltage gain boost converter is necessary to normalize the voltage of the DC-DC interface. The effect of the other parameters for instance input power and output power, total harmonic distortion, power factor on the device performance has been discussed as well.
There are three technologies of high efficiency converters are used with solar photovoltaics as an input power source: 1. Solar PV based Boost Converter (high step up DC-DC converter).

Solar PV based Boost
The ratio of change in current is held constant therefore, the gain in current is linear despite the fact that the switch is in closed condition,

Switch open condition analysis of a high step up DC-DC converter:
In switch open state, as shown in the circuit diagram of Fig. 4, the inductor current can't be change immediately. Hence, diode turn out to be in forward bias state in order to provide a smooth path for inductor current and the voltage across the inductor is given by the equation (4), assuming that the Vo (output voltage) is constant.
Output Power, The rate of change in inductor current is constant. Hence, when the switch is open, the change in current is linear. Therefore, the output voltage is known by the equation given below:  Eff at max load: 100 Watt of system having efficiency at max load 89.26% and consumes 112 watts in 1 hour and for 1 hour we need 9.33 Ah battery and for 10 hours we need 93.33 Ah battery. The graph between load and efficiency as given in Fig. 6, shows the efficiency of the system according to the load and input power is also calculated.  Efficiency calculations: The concept of efficiency is measurable and it is quantitatively determined by the ratio of valuable work performed by the machine or performed in a process to the total energy consumed or heat taken in or the ratio of useful output to the input Table 1 shows the parameters calculated for performance evaluation of an inverter. Efficiency = (Output measured / Input Measured) *100 (7) The rated output efficiency calculation from the measured data is given below:

DC-AC converter or (OFF Grid) Standalone inverters
Where, Po is the rated output power from power conditioner (kW), Pi is the input power to power conditioner at rated output (kW), ηR is the rated output efficiency (%).

Solar PV High efficiency proposed DC-DC converter: A high step up solar photovoltaic based
buck-boost converter [44]. A buck-boost converter can be obtained by cascade connection of the two basic converters as shown in Fig. 10: • Buck converter (step-down converter) [45] • Boost Converter (step-up converter) Hence, the operation of the given circuit is explained in two modes. In first condition or mode 1, switch is turned on and the function of the diode is reverse biased. Hence, input current increases instantaneously and flows through the inductor and switch. During mode 2 state, switch is in turned off state and the flow of current continues towards the inductor, capacitor, diode and load. The energy stored in this particular mode through the inductor and is transferred to the load and the inductor current (iL) falls till the switch S is turned on again in the next phase.

Analysis for switch closed condition:
While the switch is in closed state as shown in Fig. 11, the inductor voltage is given by the equation:  The rate of change in inductor current is constant and inductor current starts increasing linearly.
Therefore, the preceding equation for switch close condition is expressed as:

Economic Analysis:
Electrification in rural areas resulted in socioeconomic developments, also country dwellers are now able to operate electric appliances and devices and utilize renewable energy sources efficiently intended for expediency and also for the learning and education of their children. In this paper we proposed five functional values as shown in Fig. 15. For renewable energy generation, it is necessary to integrate power electronics segments to make improvement in power source, for instance semiconductors, switching devices, filters, heat sinks and some additional components like voltage and current sensors, various low voltage power supplies, housekeeping equipment's, control circuits etc. these tends to scale with power the Table 2 and Table 3 given below shows the procedure and performance analysis of the proposed three solar power converters respectively.    Table 5 given below shows the experimental test results of total power consumption by load. From above, DC system is having all benefits related to distances covered, efficiency, power conversion, minimum hardware, maintenance, cost etc. with using all existing electrical equipment's except ceiling fan. All existing fans are consuming 70 to 150 W of power so to run, but for solar is a very costly affair by changing it to new fan, system cost is much lower. It is believed that DC system is more hazardous than AC, but it has been test-run at various sect of peoples working on it, the shock felt by person is very much lower than 230 V AC shock. It is due to uses lower voltage (130V) than AC which is 230 V with peak of 350 V. In the Fig. 16 combined efficiencies of all the power converters using solar photovoltaics is given with different loads.
Uncertainty Measurement: Uncertainty evaluation of a result of the measured value is well defined as the margin of error of the measured quantity when clearly stated by a range of values approaching to enclose accurate calculation as shown in Table 7 which illustrates the standard uncertainty at full load and overall uncertainty limit based on the experimental values.   Table 6: Average efficiency and efficiency at full load As the above given Table 6 shows the average efficiency and efficiency at full load of all the three solar power converters. Hence, from the above MATLAB results as well as from the experimental results with theoretical analysis shows that the High efficiency proposed DC-DC converter (12 V DC System) is better in among all the three technologies on the basis of load, input power and efficiency.

Sr.
No. energy source, cost and efficiency are two main issues in the field of renewable. Hence, the primary focus is to develop a system which is low-cost and highly efficient, fitting to our national mind-set and targeted to serve the necessities of those developing countries where electricity is limited or not able to reach, e.g. low cost and highly efficient DC-AC Converters or DC-DC converter based on Solar

Converters
Photovoltaic. This research work identifies the technologies that enable the integration of renewable energy sources in the electric power system, power electronics, DC-DC converters, power management, power conversion and control for renewable energy interface, especially PV. The main features of the proposed converters include high efficiency and high voltage gain. The simplicity of its design have continuous input and output current. To conclude, the recommended concept can be prolonged without difficulty to other power transformation systems in order to achieve high-voltage demands.