• Title/Summary/Keyword: Switching Numbers

Search Result 51, Processing Time 0.035 seconds

A Study On The Realization Of Multi-Threshold Function By Partition Of Switching Functions (스윗칭함수 분할에 의한 다역치함수 실현에 관한 연구)

  • Chae Tak Lim
    • 전기의세계
    • /
    • v.23 no.4
    • /
    • pp.53-59
    • /
    • 1974
  • This paper investigates the theoretical properties of a logic element called the multithreshold threshold element, which is a generalization of the single-threshold threshold element. The primary partition os a systematic method of obtaining the multi-threshold realization of a switching function by the index numbers. The concept of comparable vertices of the same index numbers introduced in this paper is very promising for testing the multi-threshold partition by the initial condition to be defined by the minterms of the same index numbers.

  • PDF

An Effective Carrier-Based Modulation Strategy to Reduce the Switching Losses for Indirect Matrix Converters

  • Tran, Quoc-Hoan;Lee, Hong-Hee
    • Journal of Power Electronics
    • /
    • v.15 no.3
    • /
    • pp.702-711
    • /
    • 2015
  • In this paper, an effective carrier-based modulation (CBM) strategy to reduce the switching losses for indirect matrix converters (IMCs) is presented. The discontinuous pulse width modulation method is applied to decrease the switching numbers in one carrier cycle, and an optimum offset voltage is selected to avoid commutations of the high output phase currents. By decreasing the switching numbers along with avoiding commutation of the high currents, the proposed CBM strategy significantly reduces the switching losses in IMCs. In addition, the proposed CBM strategy is independent of load conditions, such as load power and power factor, and it has good performance in terms of the input/output waveforms. Simulation and experimental results are provided to verify the effectiveness of the proposed CBM strategy.

A Study on the Restoration System for Distribution Networks Using Dynamic Division Method (동적분할 기법을 이용한 배전망의 정전복구 시스템에 관한 연구)

  • 임찬호
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.17 no.3
    • /
    • pp.64-72
    • /
    • 2003
  • Comparing with transmission networks, the faults in distribution networks more often occurs because of the complicated structure and the adjacency to customers. Moreover the faults give direct damage to customers. So fault diagnosis and blackout restoration in distribution networks are very important elements to reduce the damage of customers and to maintain the stability. The restoration problem of distribution networks is subject to time. Minimizing the switching numbers in restoration process is the crucial element. In other words. the best restoration is to restore all blackout area through just one switching, if not the restoration has to be accomplished through several switching. This paper proposes the efficient restoration system in distribution networks to minimize the switching numbers. The proposed system uses the dynamic division method of hierarchical structure which consists of heuristic searching method and meta algorithm. The proposed system is applied to the sample networks, and the results showed a promising possibility.

A new approach to the minimization of switching functions by the simple table method (Simple table 방법에 의한 논리함수 최소화의 신방법)

  • 황희융
    • 전기의세계
    • /
    • v.28 no.6
    • /
    • pp.61-77
    • /
    • 1979
  • This paper is concerned with minimization process of the binary logic function. This paper describes an algorithm called the SIMPLE TABLE METHOD that well suited to minimization a switching function of any number of variables. For the Simple Table construction, a theorem based upon the numerical properties of the logic function is derived from the relationships governing minterms of the given function. Finally the minimal sum of products can be obtained in terms of the Direct Method or the Indirect Method from the table and table characteristics derived from the Simple Table. The properties and table characteristics used in this paper are described. All the minterms of a switching function are manipulated only by decimal numbers, not binary numbers. Some examples are used as a vehicle to guide the readers who are familiar with the Karnaugh map and Quine-McCluskey tabular method to this New method. These examples not only treat how to handle Don't Care miterms but also show the multiple output functions.

  • PDF

A Novel Dead Time Minimization Algorithm for improving the inverter output waveforms (인버터 출력파형 개선을 위한 새로운 휴지기간 최소화 알고리즘)

  • Han, Yun-Seok;Choe, Jeong-Su;Kim, Yeong-Seok
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.48 no.5
    • /
    • pp.269-277
    • /
    • 1999
  • In this paper, a novel dead time minimization algorithm is proposed for improving the output waveform of an inverter. The adverse effects of the dead time are mainly described by the voltage drop and the distortion factor of waveforms. The principle of the proposed algorithm is organized with forbidding unnecessary firings fo the inverter switches which are not conducted even though the gate signal is impressed. The proposed methods are explained with the conduction mode of output currents. The H/W and S/W implementation method of the proposed algorithm are also presented. The validity of the proposed algorithm is verified by comparing the simulation and experimental results with conventional methods. It can be concluded from the results that the proposed algorithm has the advantage which is able to reduce the harmonics in the output voltages and which the output voltage can nearly be equal to the reference value. Another advantage of the proposed method is the reduction of total numbers of switching so that the switching losses of inverter drives can be minimized.

  • PDF

Maximum Boost Space Vector Pulse-Width Modulation Strategy of Z-Source Inverters

  • Kim, Seong Hwan;Park, Jang Hyun
    • Journal of IKEEE
    • /
    • v.19 no.1
    • /
    • pp.73-79
    • /
    • 2015
  • In this paper, maximum boost space vector pulse-width modulation(MBSVPWM) strategy of Z-Source Inverters(ZSIs) is proposed. Conventional space vector pulse-width modulation(SVPWM) method of Voltage Source Inverters(VSIs) is modified to produce unique PWM patterns that realize the maximum boost control of ZSIs. This proposed method minimizes the switching power losses of ZSIs by reducing the numbers of the shoot-through states. Moreover, some switches keep ON state and the switching transitions do not occur during the specific sectors. An experimental system has been built and tested to verify the effectiveness of the proposed strategy.

Optimal Design of an Outer-rotor Flux-switching Permanent Magnet Motor for High Speed Operation (외전형 FSPM(Flux Switching Permanent Magnet) 전동기의 고속 운전을 위한 최적 설계)

  • Lee, Jae-Kwang;Jang, Jin-Seok;Kim, Byung-Teak
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.11
    • /
    • pp.2035-2042
    • /
    • 2011
  • In this paper, we proposed the outer-rotor type of FSPM motor for high speed operation and optimized motor shape. First of all, combinations of pole and slot numbers are examined for the optimal back-EMF and cogging torque, then optimizes the better shape design of the permanent magnet, rotor pole width. Further, The winding turns are obtained by circle of the voltage limit equation and motor parameters to minimize the current and to improve the efficiency. As a result, the performance of the designed model is satisfied, and it is verified through a two-dimensional finite element method (2D-FEA).

A Pulse Width Modulation(CPWM) Technique with Chaos Phenomenon (혼돈 특성을 갖는 펄스폭 변조(CPWM)방식)

  • Kim, J.N.;Kim, J.H.;Jung, Y.G.;Lim, Y.C.
    • Proceedings of the KIEE Conference
    • /
    • 2006.04b
    • /
    • pp.270-274
    • /
    • 2006
  • This paper proposes a Chaos Pulse Width Modulation(CPWM) technique. For generating the chaotic numbers by chaos phenomenon, chaos area $\lambda$=0.99 in bifurcation tree of the proposed double tent mapping is used. A micro-controller is used for the generation of chaos numbers and triangular carrier with chaotic frequency is obtained through the process of frequency modulation according to the generated chaos numbers. The experiments are executed with the 1.5kw induction motor coupled with a 2.5A load. The experimental results show that the voltage / current spectra are spread to a chaotic range, and the switching noise of motor is reduced by the proposed method compared to the fixed frequency PWM method.

  • PDF

A High-Level Data Path Allocation Algorithm for Low Power Architecture (저 전력 아키텍처를 위한 상위 레벨 데이터 패스 할당 알고리즘)

  • Lin, Chi-Ho
    • Journal of IKEEE
    • /
    • v.7 no.2 s.13
    • /
    • pp.166-171
    • /
    • 2003
  • In this paper, we propose a minimal power data path allocation algorithm for low power circuit design. The proposed algorithm minimizes switching activity for input variables in scheduled CDFG. Allocations are further divided into the tasks of register allocation and module allocation. The register allocation algorithm execute that it eliminate spurious switching activity in functional unit and minimize the numbers of multiplexer. Also, resource allocation method selects a sequence of operations for a module such that the switching activity is reduced. Therefore, the algorithm executes to minimize the switching activity of input values, sequence of operations and number of multiplexer. Experimental results using benchmarks show that power is reduction effect from 13% to 17% power consumption, when compared with the Genesis-lp high-level synthesis system.

  • PDF

Effect of Motor Cues and Secondary Task Complexity on Driving Performance and Task Switching While Driving (운전 중 IVIS 조작 상황에서 Motor Cue와 과제의 난이도가 과제 전환과 운전 주행에 미치는 영향)

  • Ryoo, Eunhyun;Han, Kwanghee
    • Science of Emotion and Sensibility
    • /
    • v.21 no.2
    • /
    • pp.29-42
    • /
    • 2018
  • As information technology is more actively incorporated into automobiles, the role of IVIS (In-Vehicle Infotainment System) is becoming increasingly important for providing convenience and entertainment for drivers. However, using the infotainment systems while driving requires task switching and attending to two visual resources simultaneously. We simulated a setting where participants have to drive while interacting with the infotainment system and examined how task difficulty and motor cues impact driver task-switching and driving performance, specifically whether the effects of motor cues differ depending on task difficulty. For the infotainment display, we used two types of number array depending on the congruency between the digit repetition and the chunking unit, while task difficulty was manipulated by the size of the touch-keys. Participants were instructed to dial two numbers on the screen while we recorded the dialing time, lateral position, inter-key press intervals, and steering wheel control. We found that dialing time and lateral position were affected by task difficulty, while the type of number array had no effect. However, the inter-key press intervals between chunked numbers and steering wheel movement both increased when participants had to use an incongruent number array, which indicates that, if number digits are repeated, chunking is ignored by the drivers. Our findings indicate that, in a dual-task condition, motor cues offset the effect of chunking and can effectively signal the timing for task switching.