Search results for: Yen-Shin Lai
chapter
The main theme of this paper is to propose a self-commissioning technique for high bandwidth servo drives. The presented self-commissioning technique include auto-identification of servo motor parameters and on-line calculation of controller gains of servo drives. The electrical parameters required for current controller, including stator resistance and inductance are identified under standstill....
chapter
The main theme of this paper is to propose a novel switching control method for bridgeless PFC converter to improve the efficiency by reducing both switching and conduction losses. Comparing to the conventional method, the power device is always on (no switching loss) to provide a current path via the turn-on resistor of MOSFET to reduce conduction losses under light load condition. As the load increases,...
chapter
A simple on-line auto-tuning technique for a resonant converter to achieve output voltage regulation while tuning the switching frequency to the resonant frequency is proposed in this paper. The proposed method can deal with resonant frequency variation caused by the resonant components tolerance and variation. The proposed technique is developed by detecting the zero-crossing point and peak point...
article
IEEE Transactions on Industry Applications > 2017 > 53 > 4 > 3635 - 3642
The main theme of this paper is to propose fast online optimal bandwidth search and controller tuning techniques for servo motor drives. The proposed controller tuning method derives the controller gains by searching the optimal bandwidth and identifying the inertia. The optimal bandwidth search can be achieved before oscillation occurs. It will be shown that the gains of speed controller of servo...
chapter
The controller design of servo drives for bandwidth improvement will presented in this paper. The delay issues caused by calculation, fdter and PWM generation, etc. are addressed. The controllers of current loop, speed loop and position loop are designed considering the delay and phase margin. Experimental results show the bandwidth for current, speed and position loops of servo drives are significantly...
article
IET Electric Power Applications > 2017 > 11 > 5 > 729 - 739
A novel model-free predictive current control (MFPCC) approach for three-phase AC/DC converters is proposed, which only measures the input currents and calculates their differences under different switching states. Existing model-based predictive current control (MBPCC) methods are based on converter models and thus require the knowledge of input current, input and terminal voltages, resistance, and...
chapter
An efficiency improvement method for two-stage server power by auto-tuning of bus voltage based upon new on-line switching frequency tracking technique is presented in this paper. The basic idea is to let the switching frequency to track the resonant frequency of converter to either reduce the turn-off losses or circulating losses of converter, and thereby improving the efficiency. The proposed on-line...
chapter
The objective of this paper is to present a new hybrid predictive current-mode control for power factor corrector with on-line parameter tuning. The proposed method can effectively solve the problems caused by inductance variation due to manufacturing tolerances, load current, magnetic intensity and temperature etc. for the power factor corrector with hybrid predictive current-mode control. The inductance...
chapter
The main theme of this paper is to propose fast on-line optimal bandwidth search and controller tuning techniques for servo motor drives. The proposed controller tuning method derives the controller gains by searching the optimal bandwidth and identifying the inertia. The optimal bandwidth can be achieved before oscillation occurs. It will be shown the gains of speed controller of servo drives are...
article
IEEE Transactions on Industrial Electronics > 2016 > 63 > 6 > 3942 - 3953
An improved model-free predictive current control (IMFPCC) method for synchronous reluctance motor (SynRM) drives is presented in this paper. The main advantages of previous MFPCC are that it does not require specific SynRM models and it requires neither motor parameters nor back-EMF estimations. However, this approach has two disadvantages: 1) two current measurements are required in each sampling...
chapter
The purpose of this paper is to present a new predictive current control method for three-phase AC/DC converters. The special features of the proposed predictive current control method include no need of converter model in prior and reduction of calculation time required for control. Since the proposed control method is modeless predictive control, the parameter variation will not affect the control...
article
Electronics Letters > 2016 > 52 > 1 > 49 - 50
A simplified model-free predictive current control (SMFPCC) for an interior permanent magnet synchronous motor (IPMSM) drive system is presented. The SMFPCC requires neither pulse width modulation nor a regulator. Unlike existing model-based predictive current controllers (MBPCCs), the proposed method is based on stator current detection, meaning that system parameters such as stator resistance, stator...
chapter
This work presents a model-free predictive current control (MFPCC) that is suitable for a voltage source inverter with a decoupled three-phase load. With this method, the load currents and the load current differences are available to predict the future load currents associated with eight possible switching states, generated by the inverter. Unlike model-based predictive current control (MBPCC), the...
article
IEEE Transactions on Industrial Electronics > 2015 > 62 > 11 > 6944 - 6954
A new control technique for two-stage server power is proposed in this paper. The proposed technique will significantly reduce power consumption under the light-load condition. The basic idea of the proposed control technique is to control both the dc-link voltage of the power factor corrector (PFC) stage and the switching method of the full-bridge stage. Under the light-load condition, the output...
chapter
The main theme of this paper is to propose a switching control method for LLC converter with larger magnetizing inductance to improve the light load efficiency. The proposed switching technique is to replace conventional frequency modulation method which is with constant duty while regulating the output voltage by varying the switching frequency, with pulse-width modulation while retaining the special...
article
IEEE Transactions on Industry Applications > 2015 > 51 > 2 > 1651 - 1659
A new phase-shift control technique for the phase-shift full-bridge converter is proposed to reduce thermal imbalance of power devices. For the full-bridge converter with phase-shift control, zero-voltage switching (ZVS) can be realized. However, the power devices for the leading leg are with higher thermal temperature since the related current to achieve ZVS is much higher than that for the lagging...
chapter
A new open loop control technique of boost converter to mitigate the temperature effect on current control of LED driver will be presented. The presented open loop control technique achieves zero voltage turn on in order to significantly reduce the reverse recovery loss of diode and mitigates the temperature impact on the constant current control. The basic idea of the presented control technique...
chapter
The paper presents infinite speed drives with both maximum torque per amp control and maximum torque per volt control for interior permanent magnet synchronous motor. The presented method controls infinite speed drives MTPA before flux weakening occurs. As the speed goes up further to flux weakening region II, maximum torque per volt control is achieved to give more output torque. Moreover, smooth...
chapter
The main theme of this paper is to propose an online DC-link voltage control technique of LLC converter for server power applications. The proposed technique on-line controls the DC-link bus voltage of power factor corrector (PFC) to limit the switching frequency of LLC resonant converter in order to reduce the conduction loss and switching loss (turn off loss) as the switching frequency is less and...
chapter
The paper will present a converter with multiple sources for energy harvest of internal combustion engine vehicle. The energy sources include solar panel, regeneration energy during braking and thermal electrical generator. Since these three energy sources have different power rating, a power distribution control method is proposed in this paper. The proposed power distribution control provides effectively...
