Nowadays interconnections of non-synchronous AC grids with VSC-HVDC links become attractive in preventing cascading outages. To share the spinning reserves, link is expected to balance frequencies interconnected under tolerable disturbances. Based on synchronous generator emulation control (SGEC) strategy, this paper presents a communication-free scheme for frequency regulation link. Under disturbance, scheduled powers rectifier and inverter are changed their actual powers, respectively. As...

The modular multilevel matrix converter (M3C) is a topology that can realize direct ac-to-ac power conversion. To increase the reliability of M3C, submodule (SM) fault ride-through capability required to avoid unscheduled shutdown caused by failures components in its SMs, such as open-circuit insulated gate bipolar transistors. Although this kind has been widely studied for regular dc–ac (MMC), existing diagnosis criteria and fault-tolerant control processes are not directly applicable M3C....

SUMMARY This paper deals with the design of a three-degree-of-freedom (3-DoF) parallel kinematic mechanism (PKM) high orientational capability. First, type synthesis method based on Grassmann line geometry and line-graph is proposed, novel 3-DoF PKM derived this method. Thereafter, parasitic motions are identified under two different orientation description methods, i.e., Tilt-and-Torsion angles (T&T angles) Roll-Pitch-Yaw (RPY angles), optimization considering motion/force...

Modular multilevel converter (MMC) is an attractive topology for medium- and high-voltage applications due to the merits of high modularity, easy scalability, high-quality output voltage, fault tolerance submodules. This letter focuses on control a three-phase MMC under single arm condition, which can further improve ability MMC. According three essential operating constraints MMC, this proposes feasible voltage current configuration method failed guarantee its stable operation with reduced...

The modular multilevel matrix converter (M3C) is a promising topology for high-voltage and high-power direct ac-to-ac power conversion applications. Fault tolerance ability one of the advantages M3C. To further enhance reliability M3C, this article proposes novel branch current configuration method fault conditions, which available either or two branches are failed. By deriving basic configurations analyzing dc equations under feasible can be directly derived. In terms minimizing maximum...

Envelope tracking (ET) and envelope elimination restoration (EER) are crucial techniques which can significantly improve the efficiency of radio frequency power amplification (RFPA) system in RF communication applications. The two gain more attention progress recent years, benefitting from excellent switching characteristic wide band-gap devices. amplifier (EA), a high bandwidth DC/DC converter, is entailed both to precisely amplify signal. This paper proposes modular cascaded multilevel...

Previously used ICs, which are resold as new, result in undue lost revenue, cause lower performance, reduced life span, and even catastrophic failure of platforms systems. Non-invasive inexpensive techniques needed to establish the authenticity such ICs that do not have special in-built structures for counterfeit detection. Although delay circuit increases with its age, it cannot directly reveal age chip, is also greatly influenced by process variation. In this work, we show relationship...

It is challenging to power a large number of gate drivers the series‐connected insulated bipolar transistors (IGBTs) in high‐voltage application because multiple isolated supplies are needed. In this study, novel wireless transfer (WPT) system using repeater coils designed solve problem. Every two form unit, which transfers one load. With units system, loads can obtain simultaneously. To eliminate undesirable magnetic couplings between these coils, used and same unit placed perpendicularly....

Modular multilevel converter (MMC) is difficult to operate when driving a motor with large constant load torque at low speed, due the voltage fluctuation of submodule (SM) capacitors on this condition. Quasi two-level PWM an alternative control method solve problem. This paper proposes new strategy implement quasi for three-phase MMC inverter. Arm current commutation realized by delay time each signal, and SM are kept balanced change connecting relationship between signals SMs, without...

The modular multilevel matrix converter (M3C) is an attractive topology for high-voltage and high-power direct ac-to-ac power conversion applications. SM fault-tolerant control of great importance the M3C. This letter proposes optimum common-mode voltage injection (CMV) method which can maximize input output ranges M3C after nonredundant submodules (SMs) are failed. injected CMV calculated in real-time according to relationship between fundamental reference maximum available each branch, be...

High-voltage direct current (HVDC) techniques play an important role in the power transmission, especially for distance district. For HVDC, control system is necessary to operation of flexible transmission system, so it significant research its strategy. Normally, traditional method proportional integral (PI) under dq frame but if grid voltage unbalanced, cannot reach required aim. So article proposed full-order terminal sliding mode (TSM) system. In strategy, cross-coupled term two-phase...

In this paper, a novel wireless power transfer system (WPT) is designed for powering the multiple gate drivers in modular multilevel converter. Considering that are usually distributed over long distance, repeater units designed, which placed coaxially along route. Then magnetic field can be enhanced by these and high efficiency ensured even with distance. Each unit corresponds to load consists of two coils both bipolar. Moreover, bipolar same perpendicularly remove coupling between them. A...

Switching function is very important for the dynamic phasor model of converters. It used to represent relationship between AC side voltage/current and DC in models The existing switching functions consider no effect commutation failure (CF), which restricts development A method obtain considering effects CF proposed this study. First, following a detailed analysis, two phenomenon are found that: (1) if there only single CF, then corresponding can be calculated through normal three phase...

Modular multilevel dc/dc converters (MMDC) have emerged recently for medium-voltage dc applications. Under single-circulant modulation, the submodule (SM) capacitor voltages in MMDC are found to be evenly divided only at some specific modulation coefficients. To obtain inherent balance capability under all coefficients and expand application range of circulant a simple dual-circulant is proposed this letter. On basis self-balancing SM realized by using additional switching patterns generated...

Wireless power transmission has become more and popular these years. Since the system volume is strongly related with resonant frequency, a high-frequency high-efficiency transmitter required. In this paper, high efficiency based on GaN electron mobility transistors (HEMTs) for wireless transfer presented. order to solve crosstalk problem during highspeed switching, an active miller clamp driver circuit proposed. A 320 V/5 kW, GaN-based prototype been build tested. Experimental results...

To solve the problem of crosswind disturbances and thrust boundedness for tailsitter vertical take-off landing (VTOL) unmanned aerial vehicle (UAV) control, this paper presents a control method by taking advantage aircraft's rolling freedom to decrease relax restriction on maximum thrust. First, mathematical model was constructed illustrate relationship wind direction, aircraft attitude disturbance force. Next, new extraction algorithm using direction designed based traditional backstepping...

With the development of distributed power generation, fluctuation its output may bring a higher risk serious cascading failure in an urban grid with change natural conditions. The existing assessment methods fail to consider generation. Therefore, this paper proposes method for failures grids including generation and electric vehicles. Firstly, based on probabilistic models wind power, photovoltaic, vehicles, random flow algorithm semi-invariants is applied solve flow. And then, fault chains...

Introduction: The urban distribution system plays a crucial role in efficient power within areas. increasing frequency and intensity of extreme events recent years pose significant challenges to the reliable operation systems. While extensive research focuses on emergency control strategies for large-scale grids, there is need targeted attention address arising when becomes isolated from superior grid due events. Methods: This paper aims enhance system's resilience by investigating...

When a multi-machine system losses synchronism, it may be separated into two or more electrical islands along with the separation interfaces, which are generally composed of several tie-lines. The characteristics interface tie-lines as follows. First, active power on these lines crosses zero and oscillates periodically. Second, there exits one point that is called out-of-step center interface, whose voltage fluctuation amplitude significantly larger than other points. farther away from...

In order to strike the target with high precision, beam pointing accuracy of laser weapon needs reach μrad level. The hysteresis, creep and frequency non-linearity piezoelectric ceramics (PZT) are main factors that affect system's accuracy. improve dynamic control fast steering mirror (FSM), motion principle FSM is introduced. electromechanical model mathematical object proposed. Smith predictive algorithm used design parameters validate by simulation.

In classical paradigm of model identification, a single prediction value is returned as point estimate the output. Recently, interval (IPM) has been receiving increasing attentions. Different from generic models, an IPM gives confidence that covers majority training data while being tight possible. However, due to randomness sampling data, reliability constructed uncertain. this paper, we focus on general class IPMs where fraction samples can be discarded pursue robustness, and establish...