Cascaded H-bridge Type Power Electronic Transformer Electromagnetic Interference Study Based on Parallel Simulation

A Solid-State Transformer as Enabling Technology for Microgrids for Integration into the Power Distribution System: An Overview

Power electronic transformers (PETs) contains numerous power electronic modules and multiple power conversion stages, potentially leading to an increased failure rate. The complex impacts of insulated gate bipolar transistor (IGBT) faults and strong coupling between power conversion stages make it difficult to accurately locate faults using traditional methods designed for single stage converters. To address this challenge, a simple method to locate and tolerate a single IGBT open-circuit fault of PETs is proposed, by integrating and synthesizing the dynamic characteristics of measurement signals of PET and key node information of the controller loops. The proposed method is easy to implement without using additional sensors, and it can transfer between normal operation and fault tolerant operation without noticeable inrush current or voltage. Experimental tests validate the effectiveness of the proposed approach.

Power semiconductor devices have been widely used in the fields of daily consumer goods, industrial manufacturing and transportation. Power semiconductor devices can generally be divided into two categories: controllable power semiconductors and uncontrollable power semiconductors. The first category mainly includes bipolar transistors, power MOSFET and IGBT (insulated gate bipolar transistors). The second category includes various types of power diodes. IGBT is widely used in various fields because of its advantages such as high input impedance, fast switching speed and low on-state voltage drop. However, because IGBT operation has a very high voltage and current change rate in the process of turning on and off, the electromagnetic compatibility problem caused by the module becomes more and more prominent. In this paper, the finite element simulation is used to analyze the internal structure damage caused by the repeated action of thermal stress on IGBT module, so as to study the quality and reliability of IGBT module more intuitively. IGBT device failures include total or partial functional failures (failures that occur upon commencement of operation can be excluded from failures). In addition, according to the IGBT module bonding line state (whether all failure), determination of failure boundary, so as to better show the electromagnetic interference characteristics of IGBT module failure state. Based on the basic mechanism of IGBT accelerated aging failure, finite element modeling of IGBT is carried out with Ansys software, and the simulation results are analyzed to obtain the electromagnetic interference characteristics of IGBT module during the opening and closing process.

Power electronic transformer (PET) which has a big potential application value in smart grid is an electrical power transformer device adopting power electronic converter and high frequency switch transformer. A new PET with power factor correctors (PFC) is proposed in this paper. Due to high power level of PET, PFC should have a high power level as well. Therefore, the multi-phase interleaved PFC is employed. The paper describes the one cycle control principle, proposes a current synthesis method based on IGBT current, and then analyses the relationship between ripple current and duty cycle of IGBT. In addition, the whole PFC system is simulated completely by means of Matlab/Simulink. In order to verify the theoretical analysis and simulation analysis, a four-phase interleaved PFC with a rated output power of 8.0kW is designed and implemented based on the an analog control chip. The obtained results show that the interleaved PFC by means of one cycle control and current synthesis is feasible, capable of reaching a good suppression effect of ripple current.

Since the introduction of silicon-based thyristors in 1957, researchers in the field of power semiconductor devices have achieved remarkable progress. In the late 1960s, the gate turn-off thyristor (GTO) made it possible to turn off the latching thyristor devices using their gate terminals, enabling switching frequencies exceeding 1 kHz. In the mid-1970s, new silicon bipolar junction transistors and metal-oxide-semiconductor field-effect transistors (MOSFET) were introduced, pushing switching frequencies upward above 10 kHz. The insulated-gate bipolar transistor (IGBT) was developed in the 1980s with combined features of the MOSFET and bipolar transistor that made it an appealing choice for many power electronics applications, including motor drives. Today, IGBTs are the dominant power switching devices for power electronic converters operating at voltages greater than 600 Vdc.

IGBT in power system has been dominating MOS (Metal Oxide Semiconductor) transistor since IGBTs (Insulated Gate Bipolar Transistor) guarantee better conduction loss and large current capacity. The radiation induced characteristics of IGBT are mainly emphasized the threshold shifting due to the oxide charge trapping in MOS and the reduction of current gain in the bipolar transistor being inherently composed in the IGBT structure. A lot of analysis on IGBT irradiation has been carried out by researchers. The IGBT in the converter plays an important role in switching. In this paper, the IGBT macro-model for the DC/DC converter is implemented and analyzed the electrical characteristics by SPICE simulation model. In addition, the design SPICE parameters of BF (forward beta), KP (MOS trans-conductance), and <i>V</i>_T (threshold voltage) by &gamma; radiation effects are evaluated.

Coordinated optimal dispatch of photovoltaic units with updated power electronic transformer

Power electronics transformers (PETs) have better application in smart grid because they have more advantages than conventional transformers with a structure integrating the power electronic equipment and medium frequency transformers (MF transformers). As an important part of PET, the MF transformer undertakes significant functions of voltage conversion, energy transfer and electrical isolation. Its performance determines the efficiency and reliability of the overall system. This paper mainly discusses design procedure and efficiency optimization of MF transformers. The method of computing leakage inductance is also presented to achieve the series resonance. Finally the optimal MF transformer prototype is validated with finite element simulation.

Energy and research on energy systems places a focus on all facets of electrical energy, as well as innovation in energy production and delivery, alternative resources, and efficient devices. Systems and equipment for converting, providing, and utilising energy as a kind of electricity are the subject of research initiatives. Power electronics are now a more integral part of power systems, enhancing quality and efficiency and fostering the gradual materialization of intelligent, efficient energy. Many different types of power electronics exist in power systems. The architectural study of changing electrical transformed from one medium to another is known as power electronics. Fields such as electronics reprocess or recover more than 80percent of the entire of the electricity produced at a world average rate of 3.4 billion kilowatts per hour each year. Power electronics converters, sometimes referred to as power converters or switching converters, are used to process or convert electrical energy. Electricity comes in two flavours: AC power and DC power. The distribution system is divided into AC distribution systems and DC distribution systems based on the type of power it uses. Power system analysis is an essential part of electrical power system design. Calculations and simulations are performed to verify that the electrical system, including the system components, is properly specified to perform as planned, withstand the expected stress, and be protected from failures. Advantages of Power Electronics: High power density electricity. Improved efficiency up to 99% in energy conversion. Because to its efficiency and dependability, switching power supply are also being used in medical devices with acoustically sensitive applications. Power system reliability, in general, relates to problems like service interruption and power outages. This is frequently described as a goal to try relying on codes specifically relevant to the consumer. SAIFI, SAIDI, and CAIDI are common dependability index values for US applications. DEMATEL (Decision Making Trial and Evaluation Laboratory) They are divided into analysis using the Nonmetal mineral product industry, General equipment manufacturing, Mining and washing of coal, Textile industry, Food manufacturing industry It is the interaction between the factors Visualized and assesses dependent relationships Through the structural model Also deals with identifying important. Power Electronics in Power Systems, Power Electronics in Transportation Systems, Energy Conservation, Heating &amp; Lighting Control and Renewable Energy Integration Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank. Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank.

Like the widely-used semiconductor switch, Insulated Gate Bipolar Transistors (IGBTs) are subject to many failures and degradation in power electronic converters. In Short Circuit Fault (SCF), as the most reported failures in IGBTs, drastic, sudden temperature rise, and peak SCF current are widespread failures owing to a relatively long delay of the protection subsystem. This paper proposes a protection strategy to limit the junction temperature rise by limiting the SCF current by adding a small value resistor in the IGBT emitter. Second, it reduces the SCF current to a value much less than the saturated current. With the proposed control approach, sudden temperature rise during SCF is controlled, preventing significant failure in IGBTs. The extension of the permissible SCF time is achieved even for the cases with temporary arcs. A simple control loop activates in the SCF condition and does not create slow transients for the IGBT. The results of this paper are validated through simulation and experiment.

With the development of high-frequency, miniaturized, and lightweight power electronic devices, third-generation semiconductor devices are more and more used in the main circuits of power electronic converters. The electromagnetic interference (EMI) generated by their fast switching can affect the performance of power electronic converters. Therefore, it is necessary to investigate the modeling and suppression methods of conducted noise in power electronic converters of third-generation semiconductor devices. This paper describes the EMI sources and coupling paths of EMI in third-generation semiconductor devices used in power electronic converters. The modeling methods of EMI are summarized from the perspectives of power devices and coupling paths. The suppression methods of conducted noise are summarized by suppressing EMI sources and improving coupling path characteristics. This paper provides a reference for the electromagnetic compatibility design of power electronic converters for third-generation semiconductor devices.

As more generators and loads are integrated by power electronic converters with complicated controls, electromagnetic transients (EMTs) simulation becomes an important tool for studying dynamic characteristics of large‐scale power systems. To accelerate system‐level EMT simulations, a fine‐grained parallel algorithm on graphics processing units (GPU) is proposed. By decomposing the computational models of the EMT simulation into heterogeneous, homogeneous and network solution computations, the simulations are mapped into three unified GPU kernels. To incorporate control signals and non‐linear features of electrical components, heterogeneous computations are formulated as layered direct acyclic graphs (LDAG) of primitive operations. An LDAG kernel is designed to carry out theses primitive operations efficiently by grouped threads. Then, homogeneous computations for state updates of electrical components are modelled as sets of fused multiply‐add (FMA) operations, which are concurrently processed by an FMA kernel. Moreover, a hybrid network solution kernel is designed to solve the network equations, which can adaptively select dense or sparse solvers. Large‐scale test systems are created and simulated on an NVIDIA K20x GPU. The results show that the proposed GPU‐based EMT simulations are accurate and achieve 10x speedups over the CPU‐based ones.

Power Electronic Transformer (PET) is a new type of energy conversion device in power system. The electronic transformers used in PET play an important role in performance of the overall power electronic system, including efficiency, size, and cost. The transformers are high power medium frequency transformer according to present technology. Based on a proposed circuit topology of PET, the design method of the electronic transformer is presented. A 30KW medium frequency transformer is designed. The selection of core material was based upon the optimization among the specifications: transformer size, efficiency, and producing cost. Thermal analysis is made by ANSYS. The temperature rise is checked by calculating the distribution of temperature field. The design of electric insulation of the electronic transformer is proved to be good by simulation.

As the insulated gate bipolar transistor (IGBT) modules have their own specific characteristic switching forms, their turn-on and turn-off times are changed according to practical applications. For the conventional gate drives, gate resistors are used to adjust the turn-on and turn-off times which change switching losses that have a significant amount in total losses. Collector current rate of change, $di_{C}/ dt$ and collector-emitter rate of change, $dv_{CE}/ dt$ are dependent on each other and they affect operating parameters in high power converters. Relations between current and voltages during the switching transitions are given and effects of the changes in electrical parameters for the operation of IGBT are described. Thereafter, closed-loop gate drive with analog control that performs independent control of $di_{C}/ dt$ and $dv_{CE}/ dt$ of a new generation IGBT module platform for high power applications is proposed. Unlike conventional gate drives, proposed closed-loop drive makes constant $di_{C}/ dt$ possible while $dv_{CE}/ dt$ is decreased to increase the efficiency of the power conversion system. This leads to decrease of the switching losses without changing the electromagnetic interference (EMI), IGBT voltage, and current stresses which are related with the rate of change of collector current. Simulations are performed in a double pulse test circuit in which new package next high power density dual (nHPD$^{2}$) family MBM450FS33F Hitachi dual IGBT with 3300V 450A ratings is modelled.

Adjustable speed AC drive (ASD) manufacturers recently migrated from bipolar junction transistor (BJT) semiconductors to insulated gate bipolar transistors (IGBTs) as the preferred output switching device. The advantage of IGBTs is that device rise/fall time switching capability is 5-10 times faster, resulting in lower device switching losses and a more efficient and smaller drive package. However, faster output dv/dt transitions and higher drive carrier frequencies increase the magnitude of common mode (CM) electrical noise and electromagnetic interference (EMI) problems. Experience suggests all PWM drives with steep fronted output voltage waveforms have these problems. This paper provides a basic understanding of EMI generated by these drives solutions to control EMI, as well as regulation standards on allowable conducted and radiated emissions to insure a successful drive system installation.