Kalpana Chaudhary

Effect of Ionospheric Induced Depolarization on Satellite Solar Power Station

The paper presents the ionospheric efiect on the power transmitted by satellite solar power station. Consequently, the Faraday rotation and losses due to ionospheric layer are calculated at 2.45GHz frequency. It is observed that the ∞uctuation in the Faraday rotation in day time is found to be the maximum as compared to the night hours and. Loss due to depolarization is found to have the maximum value at noon hours for all the seasons (summer, winter and spring) however, the loss is the highest for summer season as compared to winter and spring season. This is logically correct because the ionization is the highest in summer in comparison to winter which gives rise to maximum electron content and maximum depolarization.

High-efficiency rectenna design for satellite solar power station

In this work, a simple and inexpensive microstrip rectenna is designed and tested in a simulation environment. The rectenna circuit consists of 2×2 microstrip patch antenna array and Rectifier Schottky diodes. Patch antenna resonates at 2.45 GHz. A rectifier is designed and tested for impedance matching and rectification efficiency. Dickson charge pump voltage multiplier is employed in the circuit to increase output voltage considering low input power. The charge pump methodology with different stages is tested and analyzed performance wise.

Comparative Study of LEO and GEO SSPS for Some Identified Sites in India

The analysis of satellite solar power station (SSPS) is carried out for some specified locations in India and consequently the performance of the system is evaluated for geostationary earth orbit (GEO)-based SSPS and low earth orbit (LEO)-based SSPS for sites located at different latitudes. The analysis of power, the received energy over a year, and the received energy during a day for the same beam intensity show better results for LEO-based SSPS system as compared to GEO-based system. However GEO-based system is advantageous in the sense that it will deliver constant energy to the load throughout a year. Thus it is concluded that GEO-based system is suitable for base load power plant. The weight of the rectenna and hence the space required for ground station for same power output for GEO-based system is greater than that for LEO-based system which will in turn increase the overall cost of the GEO-based system. These findings may help for judicious selection of orbit for placing the satellite for SSPS.

DESIGN OF DIFFERENTIAL SOURCE FED CIRCULARLY POLARIZED RECTENNA WITH EMBEDDED SLOTS FOR HARMONICS SUPPRESSION

This work presents an enhanced rectenna with a differential source feeding scheme for radio frequency (RF) energy harvesting at 2.45GHz frequency. A circularly polarized (CP) microstrip antenna with embedded slots is designed which efficiently attains harmonics suppression. By modifying size and position of two diametrically opposite triangular projections in the top patch, two orthogonal modes that have equal magnitude and are in phase quadrature are excited. The four radial slots embedded in the antenna can block 2nd and 3rd harmonics which is suitable for onboard rectenna design without harmonics filter. A microstrip tapered feed line is used to match antenna element with 50-ohm impedance. The designed antenna is then tested for RF energy harvesting in two ways. One is conventional single source fed rectenna (SSFR), and the other is proposed differential source fed rectenna (DSFR). In the DSFR, the designed antennas are differentially operated by making a difference of λg/2 path length (λg Guided wavelength), and the ports are then connected to a differentially driven optimized rectifier circuit. For comparison, an SSFR and a DSFR are fabricated and tested. The circuit parameters in each case are optimized in Agilent Design System (ADS) 2011 software to maximize RF to direct current (DC) conversion efficiency. The proposed DSFR has a maximum efficiency (RF-DC) of 41.63% at 10 dBm RF input power. In the input power range from −20 dBm to 10 dBm, the DSFR has improved performance and higher efficiency over the SSFR.

Design Study for a 5 GW Base Load Power Drawn from Satellite Solar Power Station

In this work, satellite solar power station as base load plant model estimated analysis has performed. SSPS base load power plant for 5 GW model has investigated, and its feasibility prospects are studied. The SSPS essential components sizes have estimated for 5 GW power productions on the ground. A microwave power transmission with high beam efficiency approach is adopted in this work and beam energy effect on transmitting antenna size has examined.

Design of 5.8 GHz Rectenna for Space-Based Solar Power

In this work, a simple and inexpensive microstrip rectenna is designed and tested. The rectenna circuit consists of microstrip patch antenna array resonate at 5.8 GHz and Rectifier Schottky diodes. An HSMS-8202 diode has been investigated for the antenna and rectifier circuit impedance matching and rectification efficiency. Further Dickson charge pump voltage multiplier has employed in the rectifier circuit to increase output voltage for small microwave input power condition. The charge pump methodology with different stages is tested and analyzed performance wise.

5.8-GHz Antenna Array Design for Satellite Solar Power Station

In this work, a basic and low-cost microstrip antenna array with reduced size has been designed and tested. In the implementation level, a microstrip array antenna was realized to obtain the desired gain and directivity at a preferred frequency of 5.8 GHz. The compact antenna array consists of 2 × 2 elements microstrip patch antenna. Using simple and manual tuning method in electromagnetic full-wave momentum by Agilent Advanced Design Software, a direct control of the antenna’s resonant frequency was obtained.

Design of an Improved Differentially Fed Antenna Array for RF Energy Harvesting

This work presents an enhanced rectenna with differentially fed antenna array for RF energy harvesting. First, a linear antenna array is designed considering its side lobes less than −20 dB. Two antenna array, one with a single feed and other with differential feed, is designed to operate at 5.8 GHz. The measured peak gain of single fed and differentially fed is 13.38 and 14.29 dBi, respectively, at 5.8 GHz. The two antenna array, one with a single feed and other with differential feed, is tested for RF energy harvesting. It is observed that the differentially fed rectenna has higher output DC power than the single fed rectenna. The differentially fed rectenna has higher efficiency as compared with single fed rectenna for the power density variation from 5 to 238 µW/cm2, it has maximum efficiency (RF-DC) of 82.4% at 232 µW/cm2.

Modelling and analysis of grid-tied fuel cell system with synchronous reference frame control

There are some limitations during the interconnection of fuel cells (FCs) to the utility grid. The output voltage of fuel cell is low and unregulated DC. It should be boosted and inverted before connecting to the grid. Because of the slow response time of chemical processes in FCs, a suitable power conversion unit is needed which improves the dynamic response of the system during interconnection with the utility grid. In this work, a model of 50kW solid oxide fuel cell (SOFC) system with DC-DC boost converter and DC-AC inverter has been presented. The response of the system has been analysed through simulation results. Simulation results show the improvement in the response and validate proposal of SOFC system for grid integration.

Analysis of satellite solar power station as base load power plant

In this work satellite solar power station, as base load plant design assessed investigation is performed. A 1 GW baseload power plant SSPS has examined, and its viability prospects are deliberated. The SSPS fundamental parts dimension evaluated for 1GW power delivery on the ground. A microwave beam controlled transmission with high-efficiency approach embraced in this work and beam proficiency impact on transmitting antenna estimate analysis presented. Microwave power transmission effect on space and environment is contemplated.