Rapid Development Of Power Electronics Research Articles

Coordinated control and application of multi-terminal DC distribution system

Because of the rapid development of power electronics, DC loads, and distributed energy resources, the advantages of DC distribution systems are increasingly prominent. This paper provides a brief description of the concepts and functional advantages of DC distribution systems, introducing the main equipment of multi-terminal DC (MTDC) distribution system, the topologies, and the typical application scenarios of each topology. The coordinated control technology of MTDC distribution system is analysed and summarized in terms of control architecture, coordinated control, damping control, and operation mode. The existing MTDC distribution demonstration projects are summarized, and recent typical projects are introduced. Finally, the issues that can be studied regarding to the innovation and application of MTDC distribution system are pointed out.

The influence and application of SiC MOSFET driver modules in the contemporary power electronics industry

Technological progress has driven the rapid development of power electronics and enhanced the scale of the industry. SiC MOSFET devices have obvious advantages in applications such as high temperature resistance, high voltage resistance, and low switching loss. However, the different characteristics of such devices will bring related problems that seriously affect the reliability of the device and system. The drive circuit is effective in solving these problems with its small input resistance, parasitic inductance, and large enough drive voltage and current. Starting from the concept and related theoretical composition of SiC MOSFET driver module, this paper mainly analyses the impact of the driver module on the contemporary power electronics industry, and explains the application of the core research theory of the circuit to the industrial level. This paper also analyses the current situation of power electronics industry from the perspective of innovation theory, and looks forward to the prospect of power semiconductor devices.

Transient thermal measurement on nano-metallic sintered die-attach joints using a thermal test chip

The rapid development of power electronics has challenged the thermal integrity of semiconductor packaging. Further developments in this domain can be supported significantly by utilizing fast and flexible thermal characteristic evaluation. This study employs the transient dual interface method (TDIM) to characterize and compare the thermal resistance of Ag- and Cu-sintered die-attach joints using an in-house developed thermal test chip (TTC). The proposed TTC with 82.5% active area achieves a temperature sensitivity of 12 Ω/K and maximum power of 360 W per cell, which are 50% and 44% higher than the state-of-the-art, respectively. The uniformity of the temperature distribution (1 °C at 68 W) is verified by infrared thermography. The cost-effective manufacturing process allows the design to be applied to any substrate, such as SiC or GaN. Ag and Cu sintering is performed to bond the TTC on a Cu substrate, and the junction-to-case thermal resistance of the sintered structures is extracted. The lowest junction-to-case thermal resistance of 0.144 K/W is measured for the device sintered using Ag paste. Meanwhile, the Cu sintered structure exhibits a comparable value of 0.158 K/W. The proposed TTC in combination with TDIM accelerates the introduction of novel and cost-effective materials such as Cu.

Design and Analysis of TCSC Performance for 1200 kV UHVAC Transmission System

Background: Technical feasibility of Ultra High Voltage (UHV) Transmission system is proven through many UHV projects worldwide and research is going on to make it commercially viable. The rapid development of Power Electronics in the field of UHV AC power system has resulted in the economic and efficient transmission of bulk power over long distances. Methods: In order to improve the voltage profile of the transmission system, power transfer capability, transient and dynamic stability; Flexible AC Transmission System (FACTS) devices have been introduced at UHV level. The present paper focuses on the design and evaluation of TCSC system for the Indian UHVAC system for its Wardha Aurangabad Line, which is at present operating at 400 kV but will be upgraded soon to 1200 kV. A flow chart is prepared for the determination of the values of TCSC inductor and capacitor. Result: PSCAD/ EMTDC Software-Simulation based study is carried out to analyze the behavior of the UHV transmission line with TCSC. The effect of improvement in power transfer capability, with and without the use of TCSC scheme; through Constant- Current mode, closed-loop control has been investigated for a healthy line and a faulty line. Conclusion: With the use of TCSC, an increase of 52% is observed in the power transfer capability of the line, which is raised from about 5000 MW to 7777 MW. The paper will prove a milestone for academicians, researchers, and design engineers in the field of Power Electronics and Power Systems.

Experimental observation of destabilization in a DC bus system and its stabilization with delayed feedback control

Direct-current (DC) bus systems are expected to play a significant role in next-generation power technology because of the rapid development of power electronics. However, it is well known that the bus line voltage can become unstable when electric power through the bus line is constantly consumed by loads. Bifurcation analysis of this instability has been previously performed. It has been reported that in theory, delayed feedback control, which was developed to stabilize chaotic systems, can suppress this instability. For practical applications, it is necessary to confirm these analytical results with circuit experiments. In this study, the dynamics of a DC bus system without control and with delayed feedback control are experimentally investigated. The following three main results are obtained. First, bifurcation phenomena are experimentally found to occur with an increase in power consumption in the DC bus system without control. Second, it is experimentally found that delayed feedback control stabilizes the operating point. These results provide experimental evidence that delayed feedback control can be utilized as a stabilization method for DC bus systems. Third, it is experimentally demonstrated that the delayed feedback controller can track the operating point when the power consumption changes slowly, but not when it changes rapidly. A frequency-domain analysis is conducted to analytically estimate the upper limit of the acceptable power consumption rate of change. The estimated upper limit is useful for designing the controller and restricting the change rate of power consumption.

An Analysis on the Effectiveness of Harmonics Reduction for Variable Frequency Drive by Reactors

Recently, due to the rapid development of Power Electronics, the usage of Non Linear Load variable frequency drivers (VFDs) is increasing in the electric propulsion vessels and offshore plants. And harmonics which is generated by the variable frequency drives is an important issue should be solved. Ac line reactors and dc link reactors are widely used in variable frequency drives to improve the drive performance such as reducing input current harmonics, elevating input power factor, and protecting the drives from surges, etc. The effectiveness of both types of reactors in reducing input harmonics is affected by the loading of the drives and the system source impedance. And it considered that inductance of DC link reactors should be about 1.7 times of AC line reactors for same effect. The rules to evaluate the needs and effectiveness using ac line or dc link reactors are proposed for practical appications. In this paper, a simulation is performed to investigate of such factors using software PSIM.

A Fuzzy Based Approach for PWM Inverter fed Induction Motor V/f speed control

Induction motors are the most widely used for appliances, industrial control, and automation; however, many applications need variable speed operations. The rapid development of power electronics controllers in recent years has attracted the attention of researchers for making use of flexible characteristics of an induction motor in variable frequency drives. It presents a compact embedded fuzzy system for three-phase induction motor scalar speed control. The control strategy consists of keeping constant the voltage frequency ratio of the induction motor supply source