• Journal of Power Electronics
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• v.13 no.6
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• pp.1016-1023
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• 2013

Predictive current control offers the potential for achieving more precise current control with a minimum of distortion and harmonic noise. However, the predictive method is difficult to implement and has a greater computational burden. This paper introduces a theoretical analysis and experimental verification for an improved predictive current control technique applied to single phase grid connected voltage source inverters (VSI). The proposed technique has simple calculations. An ATmega1280 microcontroller board is used to implement the proposed technique for a simpler and cheaper control system. To enhance the current performance and to obtain a minimum of current THD, an improved tri-level PWM switching strategy is proposed. The proposed switching strategy uses six operation modes instead of four as in the traditional strategy. Simulation results are presented to demonstrate the system performance with the improved switching strategy and its effect on current performance. The presented experimental results verify that the proposed technique can be implemented using fixed point 8-bit microcontroller to obtain excellent results.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.567-570
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• 1996

A predictive current control technique for an induction motor employing a resonant DC link inverter is proposed to overcome the disadvantage of the current regulated delta modulation(CRDM) which was employed to control the resonant DC link inverter. The discrete model of an induction motor and estimation of back EMF are investigated and a novel predictive current control technique is newly developed based on this discrete model and estimated back EMF. Using the proposed control technique, the minimized current ripple with reduced offset can be obtained. The usefulness of the proposed technique is verified through the computer simulation.

• Journal of Power Electronics
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• v.18 no.2
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• pp.573-587
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• 2018

Recently evolved power electronics' based domestic/residential appliances have begun to behave as single phase non-linear loads. Performing as voltage/current harmonic sources, those loads when connected to a three phase distribution network contaminate the line current with harmonics in addition to creating a neutral wire current increase. In this paper, an enhanced performance three phase four leg shunt active power filter (SAPF) controller is presented as a solution for this problem. The presented control strategy incorporates a hybrid predictive fuzzy-logic based technique. The predictive part is responsible for the SAPF compensating current generation while the DC-link voltage control is performed by a fuzzy logic technique. Simulations at various loading conditions are carried out to validate the effectiveness of the proposed technique. In addition, an experimental test rig is implemented for practical validation of the of the enhanced performance of the proposed technique.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.2
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• pp.175-180
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• 2017

The measurement of three-phase current is important to control the instantaneous torque of a interior permanent magnet synchronous motor(IPMSM) using a three-phase inverter. Therefore, shunt resistors are used in low-cost motor-driving systems to measure three-phase current instead of additional current sensors that are too expensive for these systems. However, in certain regions of a space vector plane, shunt resistors cannot reconstruct three-phase current in high-speed driving mode. In this paper, predictive current control is used to compensate for the three-phase current in those regions, which results in a reduction of current ripple in a three-shunt sensing inverter(TSSI) and torque ripple in IPMSM.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.391-393
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• 1995

An improved predictive control technique using adaptive load estimation is proposed. The conventional predictive control technique has not concerned load variations and system parameters. Thus control performances are undesirable such as large current ripples and offset. In this paper the proposed controller employing a simple adaptive algorithm to estimate load is expected to be useful to overcome the problems of conventinal predictive controller.

• Journal of Electrical Engineering and information Science
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• v.1 no.1
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• pp.51-57
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• 1996

An improved predictive current control technique for a zero current switched(ZCS) buck-boost series resonant inverter(SRI) is proposed to overcome the inherent disadvantages such as the uncontrollable large overshoot and the large current ripple. Using the proposed technique, four quadrant operations of the output voltage and current for an uninterrutible power supply(URS) application are guaranteed and the buck-boost operation can also be obtained without an additional bidirectional switch.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.1
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• pp.36-45
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• 1998

A simple source voltage clamped resonant link (SVCRL) inverter is proposed to clamp the DC link voltage to the input source voltage and reduce the current rating of resonant inductor. The current control of a permanent magnet synchronous motor (PMSM) using a predictive current control technique (PCCT) employing the SVCRL inverter is also investigated to overcome the disadvantage of the current regulated delta modulation (CRDM) control technique. By using the PCCT based on the discrete model of a PMSM and estimation of back EMF, the minimized current ripple with small number of switchings can be obtained. Finally, the comparative computer simulation and experimental results are given to show the usefulness of the proposed technique.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1889-1900
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• 2018

Harmonic current mitigation is vital in power distribution networks owing to the inflow of nonlinear loads, distributed generation, and renewable energy sources. The active power filter (APF) is the current electrical equipment that can dynamically compensate for harmonic distortion and eliminate asymmetrical loads. The compensation performance of an APF largely depends on the control strategy applied to the voltage source inverter (VSI). Model predictive control (MPC) has been demonstrated to be one of the effective control approaches to providing fast dynamic responses. This approach covers different types of power converters due to its several advantages, such as flexible control scheme and simple inclusion of nonlinearities and constraints within the controller design. In this study, a finite control set-MPC technique is proposed for the control of VSIs. Unlike conventional control methods, the proposed technique uses a discrete time model of the shunt APF to predict the future behavior of harmonic currents and determine the cost function so as to optimize current errors through the selection of appropriate switching states. The viability of this strategy in terms of harmonic mitigation is verified in MATLAB/Simulink. Experimental results show that MPC performs well in terms of reduced total harmonic distortion and is effective in APFs.

• The Korean Journal of Pain
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• v.28 no.4
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• pp.244-253
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• 2015

Background: Although circumcision for phimosis in children is a minor surgical procedure, it is followed by pain and carries the risk of increased postoperative anxiety. This study examined predictive factors of postoperative pain and anxiety in children undergoing circumcision. Methods: We conducted a prospective cohort study of children scheduled for elective circumcision. Circumcision was performed applying one of the following surgical techniques: sutureless prepuceplasty (SP), preputial plasty technique (PP), and conventional circumcision (CC). Demographics and base-line clinical characteristics were collected, and assessment of the level of preoperative anxiety was performed. Subsequently, a statistical model was designed in order to examine predictive factors of postoperative pain and postoperative anxiety. Assessment of postoperative pain was performed using the Faces Pain Scale (FPS). The Post Hospitalization Behavior Questionnaire study was used to assess negative behavioral manifestations. Results: A total of 301 children with a mean age of $7.56{\pm}2.61$ years were included in the study. Predictive factors of postoperative pain measured with the FPS included a) the type of surgical technique, b) the absence of siblings, and c) the presence of postoperative complications. Predictive factors of postoperative anxiety included a) the type of surgical technique, b) the level of education of mothers, c) the presence of preoperative anxiety, and d) a history of previous surgery. Conclusions: Although our study was not without its limitations, it expands current knowledge by adding new predictive factors of postoperative pain and postoperative anxiety. Clearly, further randomized controlled studies are needed to confirm its results.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.539-541
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• 1994

The average current mode control of zero current switched series resonant converter is proposed. The conventional current controllers such as bang bang current controller and predictive current cantroller have some demerits like current offset and complexity. In this paper, the proposed current control technique are conventional current control techniques are comparatively studied. By the proposed control technique. the current cantroller can be simplely implemented without current offset.