Power Electronics as an Enabling Technology for Renewable Energy Integration

Blaabjerg, F.,Chen, Z. The Korean Institute of Power Electronics 2003 JOURNAL OF POWER ELECTRONICS Vol.3 No.2

The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity, to produce, distribute and use the energy as0 efficient as possible and furthermore to set up incentives to save energy at the md-user. Two major technologies will play important roles to fulfill those targets. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficiency power electronics in power systems for high efficiency and high performance applications. This paper discusses both areas, in particular the power electronic application in wind power integration.

Sensorless DTC-SVM for Induction Motor Driven by a Matrix Converter Using a Parameter Estimation Strategy

Kyo-Beum Lee,Blaabjerg, F. IEEE 2008 IEEE transactions on industrial electronics Vol.55 No.2

<P>This paper presents a new direct torque controlled space vector modulated method to improve the sensorless performance of matrix converter drives using a parameter estimation scheme. The flux and torque error are geometrically combined in a new flux leakage vector to make a stator command voltage vector in a deadbeat manner. A new sensorless method of estimating the rotor speed, flux, stator resistance, and rotor resistance is derived and verified with experimental results. Common terms in the error dynamics are utilized to find a simpler error model involving some auxiliary variables. Using this error model, the state estimation problem is converted into a parameter estimation problem assuming the rotor speed is constant. The proposed adaptive schemes are determined so that the whole system is stable in the sense of Lyapunov. The effectiveness of the proposed algorithm is verified by experiments.</P>

Effects of power cycling test condition and test strategy on lifetime estimation of power modules in power electronic systems

Choi, U.M.,Lee, J.S.,Blaabjerg, F. Elsevier 2019 Microelectronics reliability Vol.100 No.-

<P><B>Abstract</B></P> <P>One of the main purposes of an accelerated power cycling test is to develop a lifetime model for the lifetime prediction of power modules. It is important to select proper test conditions when the power cycling test is performed since it is closely related to the lifetime model parameters and also to the testing time. In this paper, the effects of power cycling test condition and test strategy on the lifetime estimation of power modules are studied. The lifetime models of the IGBT module are developed by the accelerated power cycling tests with different test conditions and also by calibrated accelerated power cycling test. As a case study, the lifetime of IGBT module in motor drive system is estimated with different lifetime models and the results are compared.</P>

An Improved DTC-SVM Method for Sensorless Matrix Converter Drives Using an Overmodulation Strategy and a Simple Nonlinearity Compensation

Kyo-Beum Lee,Blaabjerg, F. Institute of Electrical and Electronics Engineers 2007 IEEE transactions on industrial electronics Vol.54 No.6

<P>In this paper, an improved direct torque control (DTC) method for sensorless matrix converter drives is proposed, which is characterized by minimal torque ripple, unity input power factor, and good sensorless speed-control performance in the low-speed operation, while maintaining constant switching frequency and fast torque dynamics. It is possible to combine the advantages of matrix converters with the advantages of the DTC strategy using space-vector modulation and two PI controllers. To overcome the degrading of dynamic torque response compared with the basic DTC method and the phase-current distortion due to the nonlinearity of the matrix converter, an overmodulation strategy and a simple nonlinearity-compensation method using transformation are also presented. Experimental results are shown to illustrate the feasibility of the proposed strategy.</P>

Simple Power Control for Sensorless Induction Motor Drives Fed by a Matrix Converter

Kyo-Beum Lee,Blaabjerg, F. IEEE 2008 IEEE transactions on energy conversion Vol.23 No.3

<P>This paper presents a new and simple method for sensorless control of matrix converter drives using a power flowing to the motor. The proposed control algorithm is based on controlling the instantaneous real and imaginary powers into the induction motor. To improve low-speed sensorless performance, the nonlinearities of a matrix converter drive such as commutation delays, turn-ON and turn-OFF times of switching devices, and on-state switching device voltage drop are modeled using a PQ power transformation and compensated using a reference power control scheme. The proposed sensorless control method is applied for the induction motor drive using a 3 kW matrix converter system. Experimental results are shown to illustrate the feasibility of the proposed strategy.</P>

Method for Detecting an Open-Switch Fault in a Grid-Connected NPC Inverter System

Ui-Min Choi,Hae-Gwang Jeong,Kyo-Beum Lee,Blaabjerg, F. IEEE 2012 IEEE transactions on power electronics Vol.27 No.6

<P>This paper proposes a fault-detection method for an open-switch fault in the switches of grid-connected neutral-point-clamped inverter systems. The proposed method can not only detect the fault condition but also identify the location of the faulty switch. In the proposed method, which is designed by incorporating a simple switching control in the conventional method, the fault condition is detected on the basis of the radius of the Concordia current pattern, and the location of the faulty switch can be identified. By using the proposed method, it is possible to detect the open-switch fault and identify the faulty switch within two fundamental periods, without using additional sensors or performing complex calculations. Simulations and experiments are carried out to confirm the reliability of the proposed fault-detection method.</P>

Power Electronics as an Enabling Technology for Renewable Energy Integration

F.Blaabjerg,Z.Chen 전력전자학회 2003 JOURNAL OF POWER ELECTRONICS Vol.3 No.2

The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity, to produce, distribute and use the energy as0 efficient as possible and furthermore to set up incentives to save energy at the end-user. Two major technologies will play important roles to fulfill those targets. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficiency power electronics in power systems for high efficiency and high performance applications. This paper discusses both areas, in particular the power electronic application m wind power integration

Junction Temperature Estimation for an Advanced Active Power Cycling Test

U. M. Choi,F. Blaabjerg,S. Jørgensen 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

On-state collector-emitter voltage (VCE) is a good indicator to determine the wear-out condition of power device modules. Further, it is a one of the Temperature Sensitive Electrical Parameters (TSEPs) and thus can be used for junction temperature estimation. In this paper, the junction temperature estimation method using on-state VCE for an advanced active power cycling test is proposed. The concept of the advanced power cycling test is explained first. Afterwards the junction temperature estimation method using on-state VCE and current is presented. Further, the method to improve the accuracy of the maximum junction temperature estimation is also proposed. Finally, the validity and effectiveness of the proposed method is confirmed by experimental results.

A Dual Mode Operated Boost Inverter and Its Control Strategy for Ripple Current Reduction in Single-Phase Uninterruptible Power Supplies

Y. Tang,W. Yao,F. Blaabjerg 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

In single-phase uninterruptible power supply (UPS) applications, it is well known that the AC side instantaneous power is not constant by nature. The resulting input current from the DC source side will inevitably contain low frequency ripple components that may largely deteriorate the system performance in terms of efficiency and reliability. In order to solve this issue, this paper presents a dual-mode operated boost inverter, which can simultaneously work in both Differential Mode (DM) and Common Mode (CM) operations. Its DM operation ensures regulated sinusoidal AC output voltage as well as active power conversion, while its CM operation is controlled in such a way that the low frequency ripple current on the DC side can be maintained in a minimum level. The proposed ripple current reduction method may not only work with linear loads, but also nonlinear loads, where more sophisticated controller design are required. Since the presented inverter essentially consists of two DC/DC boost converters, an interleaved Pulse-Width Modulation (PWM) can be adopted to further reduce the high frequency switching ripple current on the DC side. Both Simulation and experimental results are presented to demonstrate the effectiveness of input ripple current reduction.

Model predictive control for Z-source power converter

W. Mo,P.C. Loh,F. Blaabjerg 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper presents Model Predictive Control (MPC) of impedance-source (commonly known as Z-source) power converter. Output voltage control and current control for Z-source inverter are analyzed and simulated. With MPC’s ability of multi-system variables regulation, load current and voltage regulations, impedance network inductor current, capacitor voltage as well as switching frequency fixation, transient reservation and null state penalization are all regulated as subjecting to constraints of this control method. The quality of output waveform, stability of impedance-network, level constraint of variable switching frequency as well as robustness of transient response can be obtained at the same time with a formulated Z-source network model. Operating steady state and transient state simulation of MPC are going to be presented, which shows good reference tracking ability of this control method.