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This paper presents the performance evaluation of a proposed single-phase bidirectional active neutral-point-clamped (ANPC) five-level converter (5LC) for active filtering in grid-to-vehicle (G2V), vehicle-to-grid (V2G) and vehicle-to-home (V2H) applications. In the system, the 5LC is series-connected with an electric vehicle battery charger based on a dual active half-bridge DC-DC converter (DAHBC). A cascaded strategy with a proportional-resonant compensator controls the 5LC whereas the DAHBC is controlled by a single phase-shift technique. A performance comparison is carried out for the proposed topology versus three NPC/ANPC 5L converters found in literature with similar topologies. The simulation results obtained in MATLAB-SimPowerSystems along with the experimental results obtained from a laboratory prototype validate the following: a) the first two literature topologies have the highest efficiencies, but they are incapable of balancing the voltage of the split-capacitors what increases the total harmonic distortion of both the grid current in the G2V/V2G modes and the 5LC output voltage in the V2H mode while producing a sluggish transient response, b) the 3rd literature topology like the proposed one properly balance the capacitors voltage and achieve a faster dynamics, but at the expense of an efficiency reduction, and c) unlike the former topology that continuously applies a natural but wasting unfedback voltage balancing strategy, the proposed one that includes a closed-loop control allows achieving an ANPC 5LC with a superior performance featured by a higher efficiency, a reduced switches stress, a flatter power losses distribution and a better power quality improving under the three modes of operation.

In the last years, the manufacturing and installation costs of photovoltaic generators (PV) are gradually shrinking. This reduction in costs incentives the use of PV by the end user to satisfy its own demand and sell the surplus energy to the power distribution network. This paper evaluates the competitiveness to integrate small-scale PV in the city of Quito-Ecuador. These PV will be used to self-consumption for residential and commercial users affiliated to "Empresa Eléctrica Quito", which is the entity that manages the power requirements in Quito city. The levelized cost of electricity incurred by building and operating a PV is calculated and compared with the price used to purchase energy from the electrical distribution network. The concept of grid parity is analyzed by this comparison, including electricity tariffs and costs for the year 2018. OpenDSS software is used to estimate the energy supplied from PV in function of temperature and irradiation data gathered in Quito city. Finally, annual economic benefits obtained by the users are determined. Results show that there is not grid parity in 2018 yet, but the parity status could be reached by economic incentive schemes as Net Billing. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of two novel half-switching frequency signal injection (HSFSI) demodulation algorithms for encoderless field-oriented control (FOC) of permanent magnet synchronous machines (PMSMs) intended for electric vehicle (EV) propulsion. The proposed rotating and pulsating HSFSI demodulation algorithms do not require voltage measurements or approximations for estimating the rotor position angle. The proposed HSFSI algorithms have been quantitatively and qualitatively compared by MATLAB-SimPowerSystems simulations, as well as experimentally against the two equivalent classical high-frequency signal injection (HFSI) approaches. A 2.5 kW PMSM with radially inset rotor magnets has been used for experimentally evaluating and validating the performance analysis and the comparison of the four algorithms fully implemented to work in real-time on a TI C2000 digital signal processor (DSP). The results obtained with an 80 kW interior (I)-PMSM intended for EV propulsion also show that the proposed algorithms allow a better machine control performance in terms of a smaller torque ripple generation and a faster current control loop. [ABSTRACT FROM PUBLISHER]

This paper analyzes the effects of the rotor position error in the performance of field-oriented-controlled permanent-magnet synchronous machine (PMSM) drives intended for electric vehicle (EV) traction applications. A special focus is given to the torque ripple generated along the characteristic trajectories in the different operating regions of the PMSM. An extended and generalized model of the torque ripple produced by the PMSM as a function of the rotor position error is analytically deduced. An infinite-speed interior-(I)PMSM drive and a finite-speed surface-mounted (SM)-PMSM drive are considered for the simulations carried out in MATLAB-SimPowerSystems. The experimental results have been validated with a TM4 EV drive controlling an 80-kW SM-PMSM. The torque ripple has been evaluated for both motoring and regenerative braking operation modes under maximum torque conditions going from 100 N · m at 1000 r/min up to 55 N · m at 9000 r/min. The obtained simulation and experimental results demonstrate the good accuracy of the proposed model for evaluating the torque ripple produced in PMSMs due to the error from the rotor position sensor. [ABSTRACT FROM PUBLISHER]

This paper presents a novel algorithm based on polynomial approximations (PAs) for an efficient error compensation of magnetic analog encoders (MAEs) in permanent-magnet synchronous machines (PMSMs) intended for electric vehicle (EV) propulsion. The proposed PA algorithm requires a negligible memory space compared to a very high-resolution look-up table (LUT). The use of polynomials allows compensating every possible input rotor position without carrying out an interpolation or a rounding to the nearest quantized value. The PA algorithm has been implemented to work in real time on a TM4 EV drive controlling an 80 kW PMSM. The performance of the algorithm has been validated at 6000 and 9000 r/min under +85 and {\pm}55 Nm of torque, respectively. The electromagnetic interference (EMI) effects have been minimized using a type-2 phase-locked loop (PLL). The proposed PA algorithm assisted with the PLL is capable of reducing the total position error to a range as small as {\pm}\text{0.2}^\circ$. The combination of these two algorithms is a promising solution for compensating the position error in quadrature analog encoders. The experimental results obtained with the 80 kW PMSM demonstrate the feasibility of low-cost MAEs for achieving high-performance field-oriented control (FOC) of PMSMs in EV drives. [ABSTRACT FROM PUBLISHER]