• 제목/요약/키워드: mechanical power

검색결과 7,593건 처리시간 0.037초

Effect of Pulp Properties on the Power Consumption in Low Consistency Refining

  • LIU, Huan;DONG, Jixian;QI, Kai;GUO, Xiya;YAN, Ying;QIAO, Lijie;DUAN, Chuanwu;ZHAO, Zhiming
    • Journal of the Korean Wood Science and Technology
    • /
    • 제48권6호
    • /
    • pp.869-877
    • /
    • 2020
  • The power consumption in the low consistency (LC) refining is an important indicator for the optimal control of the process and it is composed of the net power and the no-load power. The refining efficiency and process characterization of LC refining are directly affected by power consumption. In this paper, the effect of pulp consistency and average fiber length on the power consumption and refining efficiency were studied through the LC refining trials conducted by an experimental disc refiner. It is found that the curve of power-gap clearance can be divided into constant power section, power reduction section, and power increase section. And the no-load power and the adjustable domain of loading applied by the refining plates will increase as the increase of pulp consistency, while the increase of net power is larger than that of no-load power which makes the increasing of refining efficiency. Meanwhile, the adjustable domain of loading applied by the refining plates can be slightly improved by increasing the average fiber length, but its effect on the no-load power in the LC refining process can be neglected. The study of power consumption in LC refining is of positive significance for the proper selection of pulp properties in LC refining, in-depth exploration of refining mechanism, and energy consumption reduction in refining.

Power Distribution and Coordinated Control for a Power Split Hybrid Electric Bus

  • Wang, Feng;Zhong, Hu;Ma, Zi-Lin;Mao, Xiao-Jian;Zhuo, Bin
    • Journal of Electrical Engineering and Technology
    • /
    • 제3권4호
    • /
    • pp.593-598
    • /
    • 2008
  • The power distribution is proposed to determine the target operating points of the system components as the basis for maximal the efficiency of the overall system for a power split dual electric machine hybrid electric bus. The coordinated control is constructed on the basis of the power distribution. The basic coordinated control is implemented to satisfy the driver's power demand, in which both the dynamic characteristics of the engine and the dual electric machine are explicitly taken into account. Moreover, the improved coordinated control is suggested to suppress engine dynamic operation and rich fuel injection.

Improved Global Maximum Power Point Tracking Method Based on Voltage Interval for PV Array under Partially Shaded Conditions

  • Ding, Kun;Wang, Xiang;Zhai, Quan-Xin;Xu, Jun-Wei;Zhang, Jing-Wei;Liu, Hai-Hao
    • Journal of Power Electronics
    • /
    • 제14권4호
    • /
    • pp.722-732
    • /
    • 2014
  • The power-voltage (P-V) curve of photovoltaic (PV) arrays connected in parallel to bypass diodes would have several local maximum power points (LMPP) under partial shading conditions (PSC). Conventional maximum power point tracking (MPPT) methods fail to search for the global maximum power point (MPP) because the searched peak point may remain at the LMPP on the P-V curve under PSC. This study proposes an improved MPPT algorithm to ensure that PV arrays operate at global maximum power point (GMPP) under PSC. The proposed algorithm is based on a critical study and a series of observations of PV characteristics under PSC. Results show the regularity of voltage interval between LMPPs. The algorithm has the advantages of rapidly reaching GMPP, maintaining stability, and recovering GMPP quickly when the operating condition changes. Simulation and experimental results demonstrate the feasibility of the proposed algorithm.

확장된 네트워크기법을 이용한 정유압 기계식 번속장치의 동력전달 특성해석 (Analysis of Power Transmission Characteristics for Hydro-mechanical Transmission Using Extended Tetwork theory)

  • 김원;정순배;김현수
    • 대한기계학회논문집A
    • /
    • 제20권5호
    • /
    • pp.1426-1435
    • /
    • 1996
  • In this paper. a network theory for generaltransmission systme was extended considering the direction of power flow. Also, a modified network model was suggested for a node with 4 shafts in order to verify the power flow. Based on the extended network theory, a simulation program was developed to analyze a hydro-mecaanical tranmission(HMT) system consistion of two hydrostatic pump motors, severeal planetary gear trains steer differential gear. The simulation result showed that the extendednotwork analysis program develped can predict the power circulation as well as the magnitude of torque and speed for each transmission element and can be used design tool for genaral power transmission system.

산소주입 수처리 발전소용 급수펌프 밀봉장치의 누설방지 (Leakage Prevention of Mechanical Seal in a Feed Water Pumpof Power Plant with Oxygen Water Treatment)

  • 신정국;문승재;유호선
    • 플랜트 저널
    • /
    • 제7권1호
    • /
    • pp.56-63
    • /
    • 2011
  • The identifying cause of leakage problems on mechanical seal in a feed water pump of power plant have been difficult because of technical limits of domestic mechanical seal manufacturer and the various conditions of power plants. This paper can get a conclusion through the consideration study and experiment test of mechanical seal characteristics of feed water pump depending on oxygen treatment as follows. The oxygen treatment increase dissolved oxygen and cause a corrosion on the mechanical seal stationary ring composed of antimony as well as leakage problems. For solving leakage problems of seal, to eliminate dissolved oxygen in the cooling water of seal with hydrazine injection can prevent leakage problems of mechanical seal in feed water pump.

  • PDF

1.5MVA급 중용량 인버터용 IGBT 및 Stack 병렬 운전 연구 (The Study of the IGBT and Stack Parallel Operation for the 1.5MVA Medium Power Inverter)

  • 박건태;정기찬;김연달;정명길;김두식
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2004년도 전력전자학술대회 논문집(1)
    • /
    • pp.402-405
    • /
    • 2004
  • In this paper, the parallel operation of the IGBT and power stack for easy capacity enlargement series in the medium power capacity inverter system of the 660V voltage class is described. The parallel operation of the IGBT and power stack for 1.5MVA medium power inverter system's design is applied. The results of the parallel operation are described in this paper. The designed stack capacity for parallel operation is 800kVA class. For 1.5MVA inverter system, the 800kVA stack is applied with 2 parallel configurations. The 800kVA stack is designed with 3 parallel configurations of the IGBT Module. In this paper, the feasibility for easy capacity enlargement series in the medium power inverter by applying the parallel operation of the IGBT and power stack is verified. The experimental results show the good characteristics for the parallel operation of the IGBT and power stack.

  • PDF

파력발전기의 동력인출장치의 회전각도가 효율에 미치는 영향 분석 (Investigation of Moving Angle of Power Take off Mechanism on the Efficiency of Wave Energy Converter)

  • 도황팅;누엔밍치;판콩빙;이세영;박형규;안경관
    • 드라이브 ㆍ 컨트롤
    • /
    • 제12권3호
    • /
    • pp.25-35
    • /
    • 2015
  • The hydraulic power-take-off mechanism (HPTO) is one of the most popular methods in wave energy converters (WECs). However, the conventional HPTO with only one direction motion has a number of drawbacks that limit its power capture capability. This paper proposes an adjustable moving angle wave energy converter (AMAWEC) and investigates the effect of the moving angle on the performance of the wave energy converter to find the optimal moving angle in order to increase the power capture capability as well as energy efficiency. A mathematical model of components from a floating buoy to a hydraulic motor was modeled. A small scale WEC test rig was fabricated to verify the power capture capability and efficiency of the proposed system through experiments.