• 한국정밀공학회지
• /
• 제16권9호
• /
• pp.34-40
• /
• 1999

In order to establish the design technique of the robust current controller in d.c series wound motor driver system, this paper proposes a method of the compensated Bang-Bang current control using d.c series wound motor driver system under the improperly variable load to get minimum time for the torque control. The compensated Bang-Bang current controller structure is simpler than that of PID plus Bang-Bang controller. This paper shows that a general 16 bits microprocessor is efficiently used to implement such an algorithm. The calculation time of software is extremely small when compared with that of conventional PID plus Bang-Bang controller. Both nonlinear operating characteristics of digital switching elements and describing function methods are used for the analysis and synthesis. Real-time implementation of the compensated Bang-Bang current controller is achieved. The concept of design strategy of the control and the PWM waveform generation algorithms are presented in this paper.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1992년도 하계학술대회 논문집 B
• /
• pp.1038-1040
• /
• 1992

Booster is used widely as one of the step-up DC/DC power converter in power conversion process for fuel cell power plant which have the electrical characteristic of the high current density and low cell voltage. In view of control system, booster can be unstable when it is operated in broad operation range because the transfer function of booster has zero in right half plane of s-domain. So for reliable operation, controller must make the system stable in whole working range. In this paper, the two control method such as digital PID control and fuzzy control is studied for booster output voltage regulation in fuel cell plant. The design procedure of PID control and fuzzy control is described. And the experiment of designed controller action is performed in various operation points for controller performance test.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권11호
• /
• pp.544-547
• /
• 2006

In this paper, we present a temperature-controlled system for MEMS electrical resistance heaters without a temperature sensor. To rapidly control the heater temperature, the microheater system developed consists of a power supply, power amplifier, digital ${\underline{P}}roportional-{\underline{I}}ntegral-{\underline{D}}ifferential$ (PID) controller, and a quarter bridge circuit with the microheater and three resistors are nominally balanced. The microheaters are calibrated inside a convection oven to obtain the temperature coefficient with a linear or quadratic fit. A voltage amplifier applies the supply voltage proportional to the control signal from the PID controller. Small changes in heater resistance generate a finite voltage across the quarter bridge circuit, which is fed back to the PID controller to compare with the set-point and to generate the control signal. Two MEMS microheaters are used for evaluating the developed control system - a NiCr serpentine microheater for a preconcentrator and a Nickel microheater for ${\underline{P}}olymerase\;{\underline{C}}hain\;{\underline{R}}eaction$ (PCR) chip.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.1001-1003
• /
• 2004

In this paper, the vibration control of CPM(Controlled-Permanent Magnet) type magnetic levitation system of 1ton is designed and implemented. The target to be controlled has 8 magnets and 4 corners of the maglev module are levitated using a digital feedback controller. The designed controller includes PID type gap controller and speed observer. Its performance is validated by some kinds of experiments.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
• /
• pp.154-161
• /
• 1999

This paper presents a new approach to the design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles. Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme, adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaptive feedforward controller, feedback controller, and PID type time-varying auxillary control elements. The proposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.

• 한국생산제조학회지
• /
• 제5권4호
• /
• pp.26-37
• /
• 1996

This paper presents a new approach to the design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaptive feedforward controller. feedback controller. and PID type time-varying auxiliary control elements. The proposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require a an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.

• Journal of Advanced Marine Engineering and Technology
• /
• 제20권4호
• /
• pp.27-35
• /
• 1996

The ship's propulsion efficiency depends upon a combibation of engine and propeller. The propeller has better efficiency as the engine has lower rotational speed. This situation led the engine manufacures to design the engine that has lower speed, longer stroke and a small number of cylinders. With this new trends the conventional mechanical-hydrualic governors for engine speed control have been replaced by digital speed controllers which adopted the PID control or the optimal control algorithm. But these control algorithms have not enough robustness to suppress the variations of the delay-time and the parameter perturbation especially in low speed engine. In this study we consider the perturbations of the engine parameters as the modeling uncetainties and design a robust speed controller for marine medium speed diesel engine by means of $ extit{H}_{infty}$control theory having the central solution. By comparing the results of the robust speed controller with those of mechanical governor and PID controller, the validity of the robust speed controller under parameter variations is confirmed. The speed control of the experimental diesel engine of carried out using actuator which is composed of PWM signal generator and D.C servo motor.

• Journal of Advanced Marine Engineering and Technology
• /
• 제20권4호
• /
• pp.349-349
• /
• 1996

The ship's propulsion efficiency depends upon a combibation of engine and propeller. The propeller has better efficiency as the engine has lower rotational speed. This situation led the engine manufacures to design the engine that has lower speed, longer stroke and a small number of cylinders. With this new trends the conventional mechanical-hydrualic governors for engine speed control have been replaced by digital speed controllers which adopted the PID control or the optimal control algorithm. But these control algorithms have not enough robustness to suppress the variations of the delay-time and the parameter perturbation especially in low speed engine. In this study we consider the perturbations of the engine parameters as the modeling uncetainties and design a robust speed controller for marine medium speed diesel engine by means of $ extit{H}_{infty}$control theory having the central solution. By comparing the results of the robust speed controller with those of mechanical governor and PID controller, the validity of the robust speed controller under parameter variations is confirmed. The speed control of the experimental diesel engine of carried out using actuator which is composed of PWM signal generator and D.C servo motor.

• Journal of Power Electronics
• /
• 제15권2호
• /
• pp.346-355
• /
• 2015

On the basis of the conventional PID control algorithm, a modified adaptive PID (MA-PID) control algorithm is presented to improve the steady-state and dynamic performance of closed-loop systems. The proposed method has a straightforward structure without excessively increasing the complexity and cost. It can adaptively adjust the values of the control parameters ($K_p$, $K_i$ and $K_d$) by following a new control law. Simulation results show that the line transient response of the MA-PID is better than that of the adaptive digital PID because the differential coefficient $K_d$ is introduced to changes. In addition, experimental results based on a FPGA indicate that the MA-PID control algorithm reduces the recovery time by 62.5% in response to a 1V line transient, 50% in response to a 500mA load transient, and 23.6% in response to a steady-state deviation, when compared with the conventional PID control algorithm.

• 한국자동차공학회논문집
• /
• 제5권3호
• /
• pp.191-201
• /
• 1997

Accurate positioning of a throttle valve is required to implement the traction control system(TCS) which improves acceleration performance in slippery roads. In this research, position control system is developed for the main throttle actuator(MTA) system which uses one throttle actuation for small volume and DC servo motor for fast response. In order to drive DC motor, PWM signal generator and PWM amplifier were built and interfaced to the motor and controller. Digital PID control law is used as basic control algorithm. In order to prevent overshoot and improve accuracy, velocity profiles are generated and implemented whenever the targer throttle angle is given from the TCS controller. Thanks to velocity profiles, the control performance was very good and only one set of PID gains was used to cover the entire operating range. Also, the resolution of position is about 0.4$^{\circ}C$, which is better than that of stepping motor also used as throttle actuator in some products. The response time of the developed system is also fast enough to implement the engine control based TCS algorithm.