A current source inverter (CSI) requires a capacitor filter for the commutation of switching device as well attenuating harmonics. Hence, CSI-fed ac machine has second-order system in continuous time domain. This paper presents design methodology closed-loop controller drive system. multiloop using pole/zero cancellation method is employed with transfer function matrix. To decouple cross-coupling terms which cause mutual interferences between d- and q-axes synchronous reference frame, two...

This paper proposes an identification method for induction motor parameters at standstill using integral calculations. The rotor time constant and magnetizing inductance are identified. During the process, to be tested is consistently excited according a predetermined current reference. Using current, emulates rated flux slip condition, even standstill. based on calculation so that results robust measurement noise. Based these features, result of proposed quite accurate, shows excellent...

When a single-line-to-ground (SLG) fault occurs on the ac side of modular multilevel converter (MMC) in an high-voltage direct-current transmission (HVDC) system, it results ac-side voltage sag and leads to instantaneous reduction MMC power capacity. Thus, calls for ride through (FRT) strategy coordinate two stations HVDC system protect MMCs against submodule (SM) capacitor overvoltage case SLG fault. In meantime, is expected track prefault active as much possible during FRT secure...

This article proposes a magnetic flux saturation model that well represents the cross of synchronous reluctance machines (SynRMs) and parameter estimation method proposed model. Existing models do not satisfy reciprocity condition or express well. The consists terms for self-saturation saturation, it expresses nonlinear relationship between current SynRMs, as satisfies condition. data are obtained at standstill using hysteresis voltage injection method. Using data, parameters estimated....

Active noise control (ANC) algorithms have been developed within the adaptive algorithm framework. However, multichannel ANC systems, which include numerous reference sensors, speakers, and error microphones, require a very long filter converging time for estimation. Traditional system identification methods, such as Wiener method, are better suited systems because of their relatively shorter time. they large amounts data to achieve accurate statistical Therefore, this article proposes...

This paper presents a control strategy of the entire frequency range operation for Modular Multilevel Converter (MMC), especially focusing on variable speed drive an AC machine. The structure MMC essentially requires energy balancing so as to mitigate voltage pulsation each cell capacitor in converter arms. In proposed strategy, two modes are employed. One is low mode start-up and machine, other normal from medium rated To reduce pulsation, this proposes strategies at mode. Theoretically,...

This paper presents a control scheme for the Modular Multilevel Converter (MMC) to drive variable-speed AC machine, especially focusing on improving dynamic performance. Theoretically, energy balance in cell capacitors is prone be unstable at startup and low frequency operation. Therefore, MMC topology essentially requires advanced strategies balancing so as suppress voltage pulsation of each capacitor. The getting larger output lower. proposes strategy robust response even zero employing...

The AC side Single Line to Ground (SLG) fault is one of the most frequent faults in power systems. And, an HVDC system based on modular multilevel converter it calls for ride through strategy transmit maximum possible electricity during secure stability. It presents different characteristics SLG at voltage regulator and dispatcher side. In this paper a comprehensive occurred both converters proposed. proposed method fast dynamics promises transmission faults. Voltage fluctuation current...

This article proposes a novel method to reduce rotor movement when estimating magnetic flux models for interior permanent magnet synchronous motors (IPMSMs) and reluctance (SynRMs). A rotation reduction technique that considers the saturation effect is proposed. hysteresis controller used inject voltages only into <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis simultaneously xmlns:xlink="http://www.w3.org/1999/xlink">dq</i>...

A switching loss of Modular Multilevel Converter(MMC) might increase drastically in HVDC system because the number sub-module(SM) is proportional to DC-link voltage. And, a special strategy for reducing frequency has been significant research issue terms overall operating efficiency MMC system. The voltage fluctuation capacitor SM, however, increases as decreases, and with large capacitance which main portion equipment cost SM required mitigate fluctuation. In this paper, reduction proposed...

In this paper, it is presented a configuration to miniaturize HPCU (Hybrid vehicle Power Control Unit) and control strategy using FPGA logic. To the HPCU, film capacitor used as DC-link instead of electrolytic capacitor. Additionally, for minimization hardware, based controller multi-module power converter. verify feasibility laboratory load test performed. With sampling frequency digital current loop can be increased by 30% compared DSP software system.

In this paper, it is described how the circulating current flows between inverters that have isolated dc link such as cascaded H-bridge (CHB) topology when they are operating in parallel. case, zero sequence current, which normally through shared link, cannot flow However, provoked by asynchronous switching instant of devices, difference dc-link voltages parallel inverters, and unbalanced impedance. The should be suppressed a sharing inductor inserted inverters. Generally, all synthesize...

PWM strategy is classified into a Continuous (CPWM) and Discontinuous (DPWM). Because the conventional DPWM has constant non-switching period which 120° of fundamental period, could bring about high Total Harmonic Distortion (THD) compared to CPWM lower switching loss than CPWM. This paper presents carrier-based Adjustable Pulse Width Modulation (ADPWM) for 3-phase Voltage Source Inverter (VSI). The can be controlled from 0° using proposed strategy. Thus, it noted that ADPWM offers tradeoff...

This paper proposes a parameter estimation technique for self-saturation model of synchronous motors. The standstill self-identification method requires an equation-based flux saturation modeling. selected has the form polynomial representing current with respect to magnetic flux. contains unknown parameters, including exponents, coefficients, and source permanent. exponent is crucial non-linear relationship. Therefore, estimated only represents well if appropriate selected. proposed can...

This paper presents a small film capacitor inverter-based induction motor control approach to enhance with reliability and power density of three-phase variable speed drive applications. A robust hybrid controller is developed prevent performance degradation caused by the electrolytic capacitor-less inverter fed front-end diode rectifiers. The structure combines model-based voltage (MVC) hexagon manipulating (HVMC). MVC determines command output intersection torque rotor flux linkage...

Fluorescence lifetime imaging microscopy (FLIM) is a powerful technique to visualize photophysical characteristics of biological targets. However, conventional FLIM methods have some limitations that restrict obtaining high-precision images in real time. Here, we propose high-speed time-resolved laser-scanning by incorporating novel line-to-pixel referencing method into the previously suggested analog mean-delay (AMD) method. The AMD dramatically enhances photon accumulation speed for...

In this paper, it is described how the circulating current flows between inverters which have isolated DC-link such as Cascaded H Bridge (CHB) topology, when they operating in parallel. case, Zero Sequence Circulating Current (ZSCC) flowing through shared cannot flow However, provoked by asynchronous switching instant of devices and difference voltages parallel inverters. The should be suppressed sharing inductor inserted Generally, all synthesize same output voltage reference for load...

This paper presents an estimation scheme of cell capacitor voltage for the Modular Multilevel Converter (MMC) to reduce sampling data and its associated communication time coming from enormous number cells in HVDC application. For control each cell, it is necessary know state generally measured by sensors. And, sample at every instant, measurement hardware signal processing would be prohibitive as arm MMC application above several hundreds. voltages using submodule grouping adaptive observer...

This paper presents a power converter configuration for the compound type hybrid excavator with an ultra capacitor, which is directly connected in parallel to dc-link capacitor without DC/DC converter. With this structure, efficiency of system has been improved compared conventional where was via And, control strategy suggested described. To suppress oscillation voltage observer internal devised. evaluate effectiveness proposed and strategy, extensive computer simulations have performed...

This paper proposes a flux weakening control algorithm for synchronous reluctance machines based on parameters estimated at stand-still. The proposed method consists of two parts, the determination region and current reference modification. can be determined by angle between constant torque direction voltage decreasing direction. is modified magnitude output considering saturation. As result, more suitable than existing methods that assume inductances are constant. Experimental results...

This paper describes DC link voltage control method of single phase back-to-back converter for medium motor drive system. Cascaded H-Bridge (CHB) topology is widely used to achieve operation and low harmonic distortion, simultaneously. Each power cell CHB should have the isolated by using input transformer rectifier. Instead three Active Front-End (AFE) which mostly used, AFE could make structure be simple. However, even in same windings transformer, each might different due imbalance phase....

Supercapacitor is an electrical energy storage device which offers remarkably high density when compared to conventional capacitors and power batteries. While using the supercapacitors for storage, main disadvantage their limited voltage due contemporary technology restrictions. Therefore, higher operation are connected in series achieve appropriate level. Because of difference magnitude capacitance cells, local over-voltage appears on one or more supercapacitor cells. This decreases...

In this paper, a layout of Insulated Gate Bipolar Transistor(IGBT)-based Current Source Converter (CSC) to reduce stray inductance is proposed. Due the rapid evolution IGBT, it has become competitive switching device in comparison with other high power devices even MW conversion system. The higher frequency IGBT might size passive component CSC significantly, and demerits can be diminished remarkably, while merits retained. However, since speed high, overshoot voltage across due increases....

이 연구의 목적은 대학생의 소매틱 운동 재활 인식과 경험을 알아보 는 것이다. 이를 위하여 연구 방법은 한국형 온라인 공개강좌 (K-MOOC)'소매틱 재활'에 참여한 체험보고서를 분석하고 해석하였다. 그 결과는 다음과 같다. 첫째, 재활의 인식이다. 재활은 수업에서 처음 배우는 용어이며 기존의 물리치 료와 운동과는 다른 몸과 마음의 융합적 변화를 통하여 몸의 통증 을 치료하는 방안이라는 인식이 있었다. 둘째, 재 활의 경험이다. 직접 7일간의 실습으로 경험하였다. 자신의 나쁜 생활 습관과 자세로 고통을 가져온다는 사실을 인지 하였고 재활을 통해서 좋은 올바른 자세 그리 고 스트레칭을 고통에서 벗어나 심신의 건강을 유지할 수 있다고 하였다. 결국, 통증을 바로 잡고 건강한 마음을 유지하는 것이라는 알