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This paper proposes a method to successfully embedded three control waveforms, PWM (Pulse Width Modulation), PFM (Pulse Frequency Modulation), and PWM-PFM (pulse width frequency modulation), into an FPGA (Field-Programmable Gate Array) chip. The three types of control modulation are generally used in power supply design. A single function IC with PWM or PFM is already on the market. However, there is no such chip on the market to integrate these three control modulation functions into one IC chip. An HDL (Hardware Description Language) algorithm that can satisfy the above three functions at the same time is proposed and implemented in the FPGA chip. We also proposed several experimental measurements to prove that these three functions do coexist in the FPGA chip.

Several continuous-time tracking controllers of the DC-to-DC boost converters had been addressed, but few literature touched the digital tracking control because that was a challenging theoretical problem which consists of nonlinear, non-minimum phase and saturated control. Given a continuous-time nonlinear boost converter with continuous tracking control, this paper proposes a new sampled-data feedback laws from the available analog counterpart via digital redesign such that the state trajectories of the sampled-data closed-loop systems close to the continuous-time one in the sense of state-matching. An existing boost converter circuit has been demonstrated to visualize the feasibility of the proposed methodology.

The paper presents a fuzzy control method to achieve the maximum power extraction from wind power system. This control goal is called maximum power point tracking (MPPT). The buck-boost converter is used for energy conversion in MPPT control without the need to gauge the speed of the drive shaft and wind. Therefore, the cost of the wind turbine controller proposed in this paper is lower than general ones. The proposed controller is based on fuzzy rule base, so it has robust resistance to outside interference sources.

This paper investigates the use of fuzzy logic control together with Genetic Algorithm (GA) to tune corresponding membership functions in a pulse width modulation voltage (PWM)-based converter for battery charging. For quick charging purposes, a current-charging mode is built on the charging battery series with small impedance resistance. Once the rechargeable battery voltage reaches the preset output voltage value during the current-charging mode, constant voltage-charging mode should take to do the battery charging. No matter what you use a voltage/current mode for battery charging, the PWM converter with tuning duty cycle is necessary to obtain various output voltages to charge battery. The proposed pulse width modulation (PWM) control strategy based on fuzzy logic systems is applied to charge batteries for buck converter. A simulation is proposed to illustrate the efficiency of the design proposed in this paper.

A new design flow is proposed to greatly improve the efficiency and accuracy of the HDL program design. This paper successfully completes the FPGA (Field-Programmable Gate Array) chip’s external communication I2C interface design of new design flow not traditionally one. FPGA chip is often used in mobile phones, military, aerospace or other industries. Even INTEL and Microsoft and other large companies have begun to acquire FPGA-related companies, showing its importance. But the FPGA language is written in the Hardware Description Language (HDL) which is a mechanical engineering staff obstacles. Therefore, this article makes use of the MATLAB / SIMULINK tool, which is familiar with the engineering staff, to complete the FPGA chip’s I2C interface design. The advantage is that the functional simulation and HDL program can be completed at the same time, do not have to perform the function after the simulation before designing HDL program. The traditional design wastes many times to revise back and forth between function simulation and HDL program design. Finally an experimental illustration is proposed to verify the proposed design of the I2C communication interface for an HDL program on the read and write experiments of Electrically-Erasable Programmable Read-Only Memory (EEPROM).

In this paper, a new digital redesign composed of pulse width modulator (PWM) is proposed. The proposed PWM combines fuzzy logic with genetic algorithm (GA) to tune the parameter of the proposed controller such that the output response of hybrid system closely matches the one of original continuous system. Finally, an illustrated example is proposed to show the proposed method is superior to the existing one.

This paper utilizes Takagi and Sugeno’s fuzzy model to approximate the nonlinear homing missile–target dynamics. On the basis of Takagi and Sugeno’s fuzzy model we construct a robust digital controller to handle the missile for intercepting the unpredictable maneuvering target. The derived stability conditions are also proposed to support the stability of the digital closed-loop systems. An example is given to demonstrate the efficiency of the proposed missile digital controller.

The design of a rule-based controller for a class of master-slave chaos synchronization is presented in this paper. In traditional fuzzy logic control (FLC) design, it takes a long time to obtain the membership functions and rule base by trial-and-error tuning. To cope with this problem, we directly construct the fuzzy rules subject to a common Lyapunov function such that the master–slave chaos systems satisfy stability in the Lyapunov sense. Unlike conventional approaches, the resulting control law has less maximum magnitude of the instantaneous control command and it can reduce the actuator saturation phenomenon in real physic system. Two examples of Duffing–Holmes system and Lorenz system are presented to illustrate the effectiveness of the proposed controller.

In this paper, a fuzzy logic controller (FLC) for a nonlinear system with uncertain perturbation is proposed. Based on the Lyapunov synthesis approach, we construct the FLC not only to stabilize the perturbed nonlinear system but also to guarantee a prescribed H∞ norm bound of the closed-loop transfer function from the disturbance to the controlled output. A given example illustrates the availability of the proposed design method.

This paper utilizes trapezoidal rule together with Genetic Algorithm (GA) to convert a continuous-time system with input and state delays to an equivalent discrete-time one. A new method has been proposed to construct the hybrid control of sampled-data system with state and input delays via digital redesign which transforms the control law of a continuous-time system with state and input delays into an equivalent one of a sampled-data system so that the states of the digitally controlled sampled-data system closely match those of the originally well-designed continuous-time system for a relatively longer sampling period. An example is given to demonstrate that the proposed digital redesign is superior to the existing ones under a longer sampling period.

This paper deals with the robust stability problem for continuous-time linear systems with external perturbation and time delay in state and control input. We derive a sufficient condition that guarantees the closed-loop delayed system stability and a prescribed H∞ norm bound of the closed-loop transfer matrix from the disturbance to the controlled output. Based on this derivation, the proposed observer-based robust controller not only reduces the influence of the disturbance, but also guarantees the closed-loop system stability. An example is given to illustrate the availability of the proposed design method.

The design of a rule-based guidance law for homing missiles onto targets is presented. The stability of the missile-target dynamics is proven. Unlike conventional approaches that solve the Hamilton–Jacobi partial differential inequality associated with the missile guidance problem, the proposed guidance law is based on heuristic fuzzy rules. Furthermore, the proposed missile guidance control law guarantees that the missile can reach the impact region and destroy the target. An example is used to illustrate the application of the proposed design method.

In this paper, an observer-based H∞ controller for systems with time-varying delays in state and control input is proposed. Using the solution of proposed modified algebraic Riccati equation, we can construct a controller which depends on the maximum value of the time derivative of time-varying delay and guarantees a prescribed H∞ norm bound of the closed-loop transfer matrix from the disturbance to the controlled output. A given example illustrates the availability of the proposed design method.

This paper proposes a new delay-independent stability criterion for uncertain systems with state time-varying delay. Then, a robust state feedback control law based on it is constructed via sequential quadratic programming method to stabilize uncertain systems. Add a proposed FLC with a small number of rules and membership functions to the above-mentioned robust state feedback control law such that not only closed-loop uncertain systems with time-varying delay are robust stable but also output performance approaches desired one. An example given illustrates the availability of the proposed design method.

The state-delayed time often is unknown and independent of other variables in most real physical systems. In this paper, a new stability criterion for uncertain systems with a state time-varying delay is proposed. Then, a robust observer-based control law based on this criterion is constructed via the sequential quadratic programming method. We also develop a separation property so that the state feedback control law and observer can be independently designed and maintain closed-loop system stability. An example illustrates the availability of the proposed design method.

In this paper, we propose the main result (Theorem 1) obtained by a direct application of two existing results to construct the robust control and to determine the allowed perturbation bound of the continuous uncertainty systems with state delay. The uncertain stabilizable bound is shown less conservative than that of other reported. An example given illustrates the availability of the proposed design method.

A self-tuning pulse-width-modulation (PWM) control is proposed to voltage control for DC/DC buck converter. This paper not only addresses that the DC/DC buck converter with proposed PWM algorithm can attain exactly the desired output voltage but also shows that Lyapunov stability of the closed-loop system is satisfied to various conditions. Use Lead-Acid battery as the load of DC/DC converter with proposed PWM to illustrate the feasibility of regulating desired output voltage.

The purpose of this study is to investigate a scheme for normal electrical loads. Whenever electricity is being used, but its voltage, current, power are not known, long-term use may cause an increase in temperature. This, in turn, can lead to an accident. Therefore, the proposed device controls the use of electrical appliances. If the system detects that the load is in danger of voltage or current spikes, it cuts off power to electrical appliances before they are damaged. The proposed electrical device can be used to monitor the use of state methods. It uses a controller and communication interface to communicate status signals transmission to monitor the terminal. This allows users to monitor usage of electrical appliances through wireless communication devices.

This paper proposes a new method based on fuzzy logic theory to adjust the pulse width of PWM (Pulse Width Modulation) control in digital redesign and to implement it by FPGA (Field Programmable Gate Array) chip. The GA (Genetic Algorithm) is utilized to adjust the parameters of fuzzy logical system such that output response of controlled hybrid system closely matches with that of analog system.

This paper proposes a new method based on gradient operator together with interval arithmetic operations to converter a continuous-time chaotic nonlinear system to an equivalent discrete-time uncertain model. The bounds of interval system matrices via the proposed method are able to tightly enclose the exact nonlinear system. Finally we take a nonlinear chaotic circuit to illustrative our method's effectiveness.

This paper presents a fuzzy controller to solve a master-slave chaos synchronization problem. At first, the method of traditional sliding mode control is considered, which utilizes the discontinuous sign function to make the system state reaching a sliding surface. Next, fuzzy rules are determined according to the Lyapunov theorem, and the fuzzy controller is designed for chaos synchronization. Finally, an example of chaos synchronization for an uncertain Duffing-Holmes system is presented to illustrate the validity and feasibility of the proposed controller.

This paper proposes a switching control design for a rotating inverted pendulum. This design mode can be extended to any other existed control system to enhance their system performance. The existed rotating inverted pendulum control system consists of two controllers, namely, swing-up controller and stabilising controller. Here, we adopt three controller candidates to enhance system performance. A fuzzy logic control (FLC) is proposed to form the third controller candidate embedded into the existing one for the non-linear rotating inverted pendulum system. A given example illustrates the availability of the proposed design method.