Ming-Fa Tsai

Model construction and verification of a BLDC motor using MATLAB/SIMULINK and FPGA control

This paper presents the model construction of a brushless DC motor via MATLAB/SIMULINK and FPGA control, so that one can evaluate the performance of the BLDC motor control with various control schemes using MATLAB/SIMULINK. The constructed model consists of a BLDC motor dynamics block, a Hall-sensor signals generation block, a back-emf block, and a PWM-generation logic block. In order to evaluate the model, various cases of simulation studies are carried out. The control and PWM-generation logic block then can be transferred to digital hardware circuit in VHDL hardware description language for co-simulation verification in the MATLAB/SIMULINK and ModelSim environment. Experiment results by using FPGA control are also obtained to verify the correctness of the constructed BLDC model.

Design and implementation of a CPLD-based SVPWM ASIC for variable-speed control of AC motor drives

In this paper, we present the design and implementation of an SVPWM ASIC for variable-speed control of AC motor drives, employing an Altera FLEX 10K100A CPLD device. Given the d-q axes sinusoidal references from the EPROM look-up tables, the ASIC can generate alternating-reversing switching PWM sequences to control the motor speed. The firing times of the PWM sequences are functions of the switching period, the DC bus voltage, and the component voltage of the reference vector. The computation of the functions is simple, and hence can be easily carried out by digital hardware. Simulation and experimental results show the performance of the proposed SVPWM ASIC.

A novel MPPT control design for wind-turbine generation systems using neural network compensator

This paper presents a novel maximum-power-point-tracking (MPPT) algorithm in wind-turbine generation systems using neural network compensator based on the slope of the wind-turbine mechanical power versus rotation speed to avoid the oscillation problem and effect of uncertain parameters. Because the characteristics of the wind-turbine rotation speed is determined by the wind speed and air density conditions, the technologies of changing the location of the maximum power point must be developed in the applications of MPPT control in order to make the windturbine generator get the optimal efficiency from wind energy at different operating conditions. In this study, the uncertainties in wind-turbine generation systems are compensated by a neural network, the duty cycle of dc/dc converter is determined by a PI controller, and the parameters is determined by a genetic algorithm with the help of MATLAB. From the simulation results, the validity of the proposed MPPT controller can be verified under variations of wind speed, air density, and the load electrical characteristics in wind-turbine generator systems.

A novel MPPT control design for PV modules using neural network compensator

In this study, based on the slope of power versus voltage, a novel MPPT algorithm using neural network compensator is proposed to avoid the oscillation problem and effect of uncertain parameters in photovoltaic (PV) systems. However, the characteristics of PV output voltage and output current are determined by the solar irradiation conditions, ambient temperature, and the load electrical characteristics, thereby the technologies of changing the location of the maximum power point must be developed in the applications of maximum-power-point-tracking (MPPT) control in order to make the PV arrays get the optimal efficiency from solar energy at different operating conditions. In this study, the uncertainties in PV systems are compensated by a neural network and the duty cycle of dc/dc converter is determined by a PI controller. The control objectives of this study is to achieve MPPT for the PV systems including solar cell arrays, a dc/dc converter, and an output load despite the variation of solar irradiation, ambient temperature, and the load electrical characteristics in PV systems. From experimental results, the validity of the proposed MPPT controller can be verified under a certain solar irradiation and a partially shaded condition, respectively.

Design of a quadrature decoder/counter interface IC for motor control using CPLD

In this paper we present the design of a quadrature decoder/counter interface IC (ASIC) that performs the decoding, counting, and bus interface function in digital motor control systems, employing an Altera FLEX 10 KA CPLD device. The ASIC contains a pair of digital filters, a quadrature decoder, an up/down counter, a latch and inhibit circuit, and an 8-bit bus interface to a digital processing system. The design of the digital filter is based on the finite state machine model with datapath (FSMD). A novel scheme for detecting the motor rotation direction is also proposed. The ASIC can be applied to a digital motor control system for getting the rotation speed or position of the motor, which is equipped with an optical encoder. The data acquisition can be extended to 16-bit integer format by two continuous reading cycles. Simulation and experimental tests are shown to verify the ASIC functions properly.

Model reference adaptive control design for the buck-boost converter

In this study, a model reference adaptive digital control scheme is proposed for the buck-boost converter. The control design of the buck-boost converter is a challenging work because the buck-boost converter, which is a non-minimum phase (NMP) system, has a right half-plane zero. This controller design is based on the small signal model of the buck-boost converter and a reference model. A cost function of the output error and weighting control input is minimized for the buck-boost converter using the model reference adaptive control scheme. In the case that the plant parameters are uncertain (or unknown), a digital controller with model reference adaptive control scheme is proposed for the buck-boost converter using the recursive least-squares (RLS) algorithm to estimate the uncertain parameters. To verify the validity of the proposed controller, experimental set-up is built for the buck-boost converter and the fully digital adaptive controller is implemented by a digital signal processor TMS320-F28335. From the experimental results, sound performances on voltage regulation can be achieved for the buck-boost converter with uncertain parameters using the proposed controller.

CPLD realization of a digital programmable PFC control IC for single-phase half-bridge boost AC-DC converters

In this paper we present a digital programmable PFC control IC for single-phase half-bridge boost AC-DC converters, employing an Altera Flex 10K100 CPLD device. We also propose a multiple-loop control scheme for this PFC control IC to achieve a near-unity power factor under large load variations. The control scheme is simple in architecture and thus facilitates realization of the proposed digital controller using the CPLD-based circuit design approach. We adopted hierarchical, modular, and circuit resource concurrency design method for reducing the design complexity of the control IC. Owing to the high-speed nature of the CPLD, the sampling frequency of the constructed IC can be raised up to the range that cannot be achieved using a conventional microprocessor-based digital controller. Besides, the control parameters in this IC are programmable and the variables can be observed via an interface to a monitoring processor. Simulation and experimental results are presented to verify the viability of the proposed control IC.

Modeling and estimation of state of charge for Lithium-Ion batteries using ANFIS architecture

This paper presents the modeling and estimation of state of charge (SoC) for Li-ion batteries using ANFIS architecture. The system consists of two phases of operation. The phase 1 is the SoC modeling process. The phase 2 is the real-time estimation process. Firstly, on the phase-1 operation, a brand-new Li-ion battery is used for a completely discharge cycle which consists of 355 cycles of discharge/charge command profile to collect the data of extracted charge, internal resistance, and no-load voltage for training the ANFIS. On the phase-2 operation, the trained parameters of the system are then used to construct the estimator by using MATLAB/SIMULINK. The estimator is then used for the estimation the SoC of a Li-ion battery under test by getting the data using only one cycle of the command profile. Finally, four Li-ion batteries are tested and the result shows the brand-new batteries have higher SoC value than the used batteries.

Design and implementation of an FPGA-based digital control IC of maximum-power-point-tracking charger for vertical-axis wind turbine generators

This paper presents the design of an FPGA-based digital control IC of maximum-power-point-tracking (MPPT) charger for vertical-axis wind turbine generators. The output of the charger can be connected to a 48V battery to supply power to a DC load or an electric vehicle drive system. A novel MPPT scheme, which is the mixing of the conventional perturbation and observation method and a linear approximation method, to get the maximum output power of the wind turbine generation system with faster tracking speed is proposed. The simulation model of wind-turbine generation is built in PSIM simulation software tool and used to analyze the converter and MPPT system operation under different wind speed conditions. Based on the simulation model, the digital control IC of the MPPT charger is then designed. The digital MPPT control IC has been designed by using VHDL hardware description language. The simulation models for the MPPT control IC have also been constructed and verified by using Simulink, ModelSim, and PSIM cosimulation tools. The designed circuit has been implemented on an Altera Cyclone FPGA logic device. Simulation and experimental results are shown to verify the viability of the proposed control IC of the MPPT charger.

Design of a Digital Programmable Control IC for Single-Phase Controlled Rectifiers

This paper presents the design of a digital programmable control IC which is intended for controlling thyristors to produce a constant current source via a single- phase controlled rectifier. The architecture of the control IC consists of three major parts: a single-phase controlled triggering circuit, an inverse cosine look-up table, and a proportional-integral current controller. All the three parts have been designed using VHDL language. The simulation model of a constant current source based on a single-phase controlled rectifier has also been constructed by using Simulink and ModelSim cosimulation tool. The designed control IC circuit has been implemented on an Altera Flex 10K FPGA logic device. Further, the control parameters in this IC are programmable and the variables can be observed via an SPI interface to a monitoring processor. Simulation and experimental results are shown to verify the viability of the proposed control IC properly