Francisco J. Perez-Pinal

Bio: Francisco J. Perez-Pinal is an academic researcher from Instituto Politécnico Nacional. The author has contributed to research in topics: Boost converter & Power electronics. The author has an hindex of 9, co-authored 56 publications receiving 390 citations. Previous affiliations of Francisco J. Perez-Pinal include Mohawk College & McMaster University.

A New Common-Mode Transformerless Photovoltaic Inverter

Abstract: Transformerless inverters are being widely used in grid-connected photovoltaic (PV) generation systems. Transformer elimination, in grid-connected PV systems, has many advantages. This not only reduces cost, size, and weight, but also increases the whole system efficiency. However, once the transformer is removed, there is no galvanic isolation between grid and PV array; as a consequence, leakage current appears due to parasitic capacitance to the ground, resulting in prohibitive electromagnetic interference and security issues.

Relative coupling strategy

Abstract: Multi-motor arrangements have grown as an important field in the manufacturing process where high-performance applications that are able to achieve precise control of position, speed, acceleration, and deceleration are required. Several approaches exist for such synchronisation control all of them with the main aim to synchronize multiple machine axes and to emulate the actions of the mechanism they replace. However, so far little work has been done in the relative speed and position error between axes during the start-up, shutdown conditions and under load impacts on any motor. This paper present a novel multi-motor synchronisation strategy called relative coupled strategy, which can be easily applied into a real industrial environment. This novel approach is specifically compared with the electronic (virtual) line shaft. Results are presented showing the ability of the novel and current strategies to cope with different load conditions.

Stability of an Electric Differential for Traction Applications

Abstract: The use of an electric differential (ED) constitutes a technological advance in vehicle design along the concept of more electric vehicles (MEVs). EDs have the advantage of replacing loose and heavy mechanical differentials and transmissions with lighter and smaller electric motors directly coupled to the wheels via a single gear or an in-wheel motor. To date, EDs have been proposed for two- and four-wheeled vehicles. Despite its long reported success and possible advantages in terms of flexibility and direct torque control of the wheels during cornering and risky maneuvers, the ED has several problems that have limited its applicability, for instance, an increment of control loops and an increase of computational effort. Therefore, the main purpose of this paper is to present a simple and easy-to-implement ED that ensures both reliability and good path tracking. The proposed strategy has the advantage of being linear and, therefore, easy to implement. Furthermore, a rigorous proof of stability is presented, and connections with other controllers are discussed. Features and advantages of the proposed scheme are illustrated via numerical simulations in a 4-kW system, which is able to handle 500-kg mass and deliver peak power up to 10 kW during transit periods.

Performance comparative of OpenCV Template Matching method on Jetson TX2 and Jetson Nano developer kits

Abstract: Template Matching is a widely used method for object detection in digital images, it requires great processing power since it is an exhaustive method that compares the intensity levels of a source image pixel-to-pixel with a template image that contains the object to identify. Nowadays there are dedicated embedded systems that provide high processing capabilities, such as the NVIDIA Jetson family. This work presents the experimentation and the performance comparison between the Jetson Nano and Jetson TX2 development kits, when implementing the Template Matching method, in order to get an evaluation criterion to select one of them in image processing projects. It was carried out to six images with different sizes and two variants in terms of the size of the template image. The processing times for the sequential implementation using the CPUs and the parallel implementation with the GPUs were obtained quantitatively. It was observed that the processing times using the parallel versions on average doubled those of the sequential versions and that the Jetson TX2 exceeded the Jetson Nano in execution speeds.

Hexagonal Geometry Coil for a WPT High-Power Fast Charging Application

Abstract: Magnetic cores for inductive wireless power transfer (WPT) have many applications and regularly use E, U, pot, and planar/circular shape coils. The systems for wireless energy transfer are not conveniently in the power levels required for some applications, as for the electric vehicle (EV), for instance, and there is a necessity to study different coil geometries to improve its efficiency and decrease its volume and weight. In this article, we presented a new hexagonal-geometry coil design placed in the secondary of a WPT, and the tests demonstrate that a Type-II system compliance requirements (SAE J2954) can be accomplished with greater efficiency and lighter weight compared to the circular coil. Finite element analyses accurately allow predicting the mutual inductance and achieving the optimal coil parameters and an experimental setup allows obtaining a rated power output of 7.7 kW operating at 85 kHz. The experimental testbed comprises a series-series resonance compensation circuit, a spiral coil used as primary, the proposed hexagonal pad for the secondary coil, and an ac-output, half-bridge inverter as a source, achieving a lighter, and efficient system in a realist scenario.

Review of Battery Charger Topologies, Charging Power Levels, and Infrastructure for Plug-In Electric and Hybrid Vehicles

Abstract: This paper reviews the current status and implementation of battery chargers, charging power levels, and infrastructure for plug-in electric vehicles and hybrids. Charger systems are categorized into off-board and on-board types with unidirectional or bidirectional power flow. Unidirectional charging limits hardware requirements and simplifies interconnection issues. Bidirectional charging supports battery energy injection back to the grid. Typical on-board chargers restrict power because of weight, space, and cost constraints. They can be integrated with the electric drive to avoid these problems. The availability of charging infrastructure reduces on-board energy storage requirements and costs. On-board charger systems can be conductive or inductive. An off-board charger can be designed for high charging rates and is less constrained by size and weight. Level 1 (convenience), Level 2 (primary), and Level 3 (fast) power levels are discussed. Future aspects such as roadbed charging are presented. Various power level chargers and infrastructure configurations are presented, compared, and evaluated based on amount of power, charging time and location, cost, equipment, and other factors.

Grid-Connected Integrated Battery Chargers in Vehicle Applications: Review and New Solution

Abstract: For vehicles using grid power to charge the battery, traction circuit components are not engaged during the charging time, so there is a possibility to use them in the charger circuit to have an onboard integrated charger. The battery charger can be galvanically isolated or nonisolated from the grid. Different examples of isolated or nonisolated integrated chargers are reviewed and explained. Moreover, a novel isolated-high-power three-phase battery charger based on a split-phase permanent-magnet motor and its winding configuration is presented in this paper. The proposed charger is a bidirectional high-power charger with a unity power factor operation capability that has high efficiency.

Design of loosely coupled inductive power transfer systems

Abstract: The model of inductive power system is set up,and how to choose the compensation topology and resonant frequency is analyzed.According to the analysis result,the model of inductive power system is set up,and the impact of the power transfer due to the variety of load is analyzed.