Electrical Efficiency Increase in CPVT Collectors by Spectral Splitting

Concentrating photovoltaic-thermal (CPVT) collectors have to face the challenge of contrary temperature requirements in the single receiver parts. The PV cells require low temperatures to achieve high efficiency, whereas the thermal part should generate high temperatures for providing industrial heat. The approach of “Spectral Splitting” can offer a solution for compact CPVT receivers; however, a clear quantification of the expected conversion efficiency is difficult. Therefore, this paper describes a modelling methodology for obtaining electrical and thermal performance parameters for a Spectral Splitting configuration using semiconductor-doped glass combined with appropriate heat transfer fluid. The PV technologies c-Si, CIGS and CdTe are considered. The presented model yields distinct results for maximising the electrical efficiency, calculates the reduction in waste heat dissipation within the cells and assesses the impacts of concentration factor and cell temperature. An optimised configuration could be found with CIGS cells, impinged by a selected wavelength spectrum between 868 nm and 1100 nm, where the theoretical efficiency reaches 42.9%. The waste heat dissipation within the cells is reduced by 84.9%, compared to a full-spectrum operation. The depicted CPVT receiver design using bendable thin-film PV cells will be realised as a prototype in a subsequent project phase.

A Novel Optimized V-VLC Receiver Sensor Design Using μGA in Automotive Applications

Vehicular visible light communication is known as a promising way of inter-vehicle communication. Vehicular VLC can ensure the significant advancement of safety and efficiency in traffic. It has disadvantages, such as unexpected glare on drivers in moving conditions, i.e., non-line-of-sight link at night. While designing a receiver, the most important factor is to ensure the optimal quality of the received signal. Within this context, to achieve an optimal communication quality, it is necessary to find the optimal maximum signal strength. Hereafter, a new receiver design is focused on in this paper at the circuit level, and a novel micro genetic algorithm is proposed to optimize the signal strength. The receiver can calculate the SNR, and it is possible to modify its structural design. The micro GA determines the alignment of the maximum signal strength at the receiver point rather than monitoring the signal strength for each angle. The results showed that the proposed scheme accurately estimates the alignment of the receiver, which gives the optimum signal strength. In comparison with the conventional GA, the micro GA results showed that the maximum received signal strength was improved by −1.7 dBm, −2.6 dBm for user Location 1 and user Location 2, respectively, which proves that the micro GA is more efficient. The execution time of the conventional GA was 7.1 s, while the micro GA showed 0.7 s. Furthermore, at a low SNR, the receiver showed robust communication for automotive applications.

Area-Efficient Universal Code Generator for Multi-GNSS Receivers

Although conventional global navigation satellite systems (GNSS) receivers were originally designed for single signals, studies on multi-signal receiver design have recently been actively conducted to achieve high accuracy, precision, and reliability. However, in order for a multi-signal receiver to support various codes, the receiver should support the generation of individual codes. Therefore, the resulting problem of increased complexity must be solved. This paper proposes a hardware structure for an area-efficient linear feedback shift register (LFSR)-based multi-frequency universal code generator. Whereas the existing universal code generators were configured so that feedback polynomials, output registers, and initial values can be selected by placing read-only memories (ROMs), multiplexers (MUXs), and exclusive ORs (XORs) by register bit, in the case of the proposed universal code generator; the circuit was implemented by applying the hardwiring technique to those register bits that have fixed values. According to the results of field programmable gate array (FPGA) implementation, the proposed LFSR-based universal code generator can improve look up table (LUT) by up to 37% and register by up to 78% when compared to conventional code generators, and LUT by up to 36% when compared to the previous universal code generator. Therefore, the proposed universal code generator is a good candidate for implementing multi-frequency receivers to achieve high precision and high reliability.

Multi-GNSS Software Receiver Design Optimization for Accuracy Improvement

Recently, tremendous research has been conducted on Global navigation satellite systems (GNSS) software receivers to better serve the current challenging environments that suffers from multipath fading. Therefore, the development of GNSS receivers has seen a new rush toward a multi-GNSS as a solution for fading problems. In this paper, a multi-GNSS software receiver is designed, optimized, and its performance is presented. The implemented software receiver covers three different signals from two GNSS constellations, namely GPS L1, GPS L2, and Galileo E1. In this paper. the fundamentals of stages of GNSS signal reception (acquisition, tracking, and navigation) are discussed where each stage is customized and optimized for each considered signal and the stage of mutli-GNSS data combination is optimized afterword. The performance of the optimized multi-GNSS software receiver is examined under different combination scenarios where the Least-Square Estimation (LSE) method using precise positioning (PP) algorithms is adopted. Results showed that using multi-GNSS receiver enhances the accuracy of Position, Velocity, and Timing (PVT) solution. Keywords: GNSS, PVT, GPS, Galileo, and accuracy

On-Sun Testing of a High Temperature Solar Receiver's Flux Distribution

Concentrated solar power (CSP) is a promising technology in transitioning to renewable energy because of its abundance in nature and thermal energy storage capability. Among the four types of available CSP technology, including parabolic trough, linear Fresnel, power tower, and parabolic dishes, a power tower using a central receiver has more potential to generate high-temperature heat in a scale supporting power cycles efficiency and achieve low levelized cost of energy (LCOE). Other than the conventional type of receiver design, the high-absorptive receiver concept developed and presented in this paper is novel in its design approach. The novel receiver design originated from National Renewable Energy Laboratory (NREL) consists of an array of solar flux absorb tubes. The solar absorb tubes require uniform flux distribution and in-depth flux penetration through the three different reflective sections of tubes in a hexagonal shape. To evaluate this unique receiver design and thermal performance, the flux distribution, flux uniformity, and intensity were numerically simulated using ANSYS FLUENT and SolTrace modeling program. On-sun testing has been done at NREL high flux solar testing facility, based on the computational analysis.

Research on Dual-Phase Non-Salient Pole Receiver for EV Dynamic Wireless Power Transfer System

Dynamic wireless power transfer (DWPT) technology shows a vast development prospect for EV application, with advantages of reducing the demand for battery capacity and improving the user experience. However, the need to improve output performance leads to a challenge in receiver design with limited space and allowable load on the EV side. In this paper, a design of a dual-phase non-salient pole (NSP) receiver for the EV DWPT system with bipolar transmitter is proposed, aiming at providing a solution to the contradiction between reducing the volume or cost and improving the misalignment tolerance of the receiver. The coupling principle of the proposed receiver is analyzed. The structure parameters are optimized by the finite-element simulation method. Combined with specific design indexes, it is proven by comparison with the existing dual-phase receiver that the proposed receiver is 35.4% smaller in volume and needs 47.0% shorter wires. Moreover, the significant advantage of the proposed dual-phase NSP receiver in misalignment tolerance is verified by simulations and experimental comparisons.