power consumption and ef ciency as the metric

... numbering) This aspartate fi histidine replacement is the basis for the unforeseen binding of Zn(II) at the ferroxidase center, and most likely for the high ef ciency of O2 as Fe(II) oxidant These properties ... that identify the two metals at the A-site and the B-site disappear when the map is contoured at 10r and 7r, respectively The bound metal ions were assigned to Zn(II) on the basis of the presence ... [41] A B C the loss of the typical funnel shape of the pores and in an increase in their cross-section (Fig 2B) Furthermore, the nature and spatial arrangement of the residues lining the pore change...

Ngày tải lên: 15/03/2014, 09:20

... its parameters The fact that we witness some of these mediators as types and others as relations is simply an intensional reflection of how the grammar writer thinks of them In classical HPSG, ... in HPSG in the name of parsing ef ciency While a definitive measurement of the computational cost of this functionality has yet to emerge, there is at least no apparent indication from the experiments ... TFS (the implicit universal quantification is still there), either the consequent holds, or the TFS is not subsumed by the most general satisfier of α The subsumption convention dates back to the...

Ngày tải lên: 20/02/2014, 15:21

... reactive power injection either locally, at the wind farm, or globally, in the whole network As a result of the optimum and coordinated reactive power dispatch, the voltage stability in the power ... conventional thermal, hydro, and nuclear generation and wind power, such as different generation systems and the difficulty in controlling the primary movement of a wind turbine, due to the wind and its ... generation as well as of the basic commercial wind turbine configurations Chapter contains the results of research activities in line to reduce both: the uncertainties in power forecasting and the lack...

Ngày tải lên: 20/06/2014, 05:20

... load power to changes in G and B In the area to the right hand side, load has positive sensitivity to changes in G and B, whereas in the area to the left hand side if G and/ or B is increased ... Furthermore, as much as reactive power injection of wind farms longer the voltage collapse point Fig shows the voltage profile at the base loadability of the case studied (λ=0), at the base case and after ... of the P- locus, the Q locus and the BL In other words, if the intersection point of the P-locus with the BL and the intersection point of the Q-locus with the border line coincide with each other,...

Ngày tải lên: 20/06/2014, 05:20

... standard of measurement and testing of the power quality supplied by the wind turbines The works on the quality standards of the power supplied by the wind turbines began in 1995 by the IEC At the end ... active power and the applied voltage Assuming that the voltage is almost constant, the reactive power depends only on the active power Typically, a capacitor compensates, at least, the reactive power ... taken into account are the turbine maximum power generation and minimum power consumption (by other of users), and minimum wind power and maximum power consumed The limit of the permissible voltage...

Ngày tải lên: 20/06/2014, 05:20

... resonance frequency, i.e as in the two previous cases, increasing the inductive impedance or the capacitive impedance the frequency of the resonance decreases In the analyzed cases, the biggest variation ... (red) and 12% (green) As is shown in Fig 8, as the leakage inductance of the step-up transformer increases, the frequency of the resonance decreases (from 450Hz to 350Hz) For the specific case ... increment in the inductance toward the center and the current tends to crowd toward the outer surface So at higher frequencies the effective cross section area of the conductor decreases and AC resistance...

Ngày tải lên: 20/06/2014, 05:20

... and control • To achieve high conversion efficiency and therefore low loss • To minimize the mass of power converters and the equipment (such as motors) that they drive • Intelligent use of power ... each The goal of the model is to calculate the active power provided by the wind generator, given the measured values of wind speed and his direction (Feijoo & Cidras, 2001), as well as the reactive ... where V is the voltage, P is the real power, X is the sum of the stator and rotor reactances, Xc is the reactance of the capacitor bank, Xm is the magnetizing reactance, and R is the sum of the stator...

Ngày tải lên: 20/06/2014, 05:20

... called the gate closure At the time of gate closure, the market therefore has all the information needed to define, based on production offers and demand loads, the best compromise towards the power ... 85 The optimal solution is feasible and the value of the objective function varies linearly with the inverse of the variation of δ The more δ increases, the more the objective function decreases ... has to suit the storage capacity, the wind power capacity and the quality of forecasts It is possible to plan the operation rather medium-term (days, weeks, month or season) It can be called the...

Ngày tải lên: 20/06/2014, 05:20

... voltage (Efd) of the SG and the direct-current set point (Iref) of the converter The measurements are the voltage amplitude (Vb) and the frequency (f) of the AC bus The wind speed (ν) and the load ... promising The input to the controller consists in the difference between the maximum output power from the WES and the output power from the asynchronous link and, the derivative of this difference The ... connecting the load to the main bus is used to fit the frequency of the power supplying the load as well as the voltage Fig shows the overall structure of wind-battery system: Efd is the excitation...

Ngày tải lên: 20/06/2014, 05:20

... operations and during grid faults, by limiting the mechanical power extracted from the wind and thus restoring the balance between electrical and mechanical power The efficiency of the pitch control ... the currents to the reference values that are specified by the outer slower power controller PI PI PI PI PI PI PI PI U dcref Pr ef Qref GSC Qref grid = U dc ref = co nst Qref grid ≠ ω gen Qref ... values of power) – SCENb • The Maximum Wind Power Penetration scenario (in percentage of the load demand) – SCENc The first scenario is the base case scenario and is used to evaluate the operational...

Ngày tải lên: 20/06/2014, 05:20

... comparing the frequency response in both cases In SCENb (see Figure 33 – case (a)), the frequency does not decrease as much as in SCENc (see Figure 38 – case (b)), therefore, the rotor of the ASIG ... in the development and planning of their public electric systems; the first is the increase in the generation power from RES and the second one is the transition to open electricity markets These ... wind power is only as reliable as the weather forecastingE.ON-Netz (2004) If the wind power forecast differs from the actual infeed, the TSO must cover the difference by using the reserves, which...

Ngày tải lên: 20/06/2014, 05:20

... factor The ef ciency factors ηs and ηr in a hydraulic system are the ef ciency of the pump in storage phase and the turbine in the recover one respectively The output power that is sent to the grid, ... energy, as well as the maximum and minimum energy values In the columns without the innovation term, the Reference Model performs better than the other forecasting It has the lowest values in out band ... P (t) − P ] P (t) > P + δ1 otherwise (10) where ηs is the ef ciency of the driver in the storage phase, and δ1 ≤ Δ The decrease of energy in the recovery phase is the following when E > 0: ˙...

Ngày tải lên: 20/06/2014, 05:20

... forecast wind generation power with 10-min resolution Current and previous wind speed and wind power generation are used as input parameters to the network where the output from the ANN is the ... 12-hour, and 24hour wind speed predictions are evaluated in least square error sense and the prediction coefficients are then used in the state space stochastic formula representing past and future ... bi x(n  i ) i 1 Where N is defined as the prediction order (using N past data samples) and the coefficients {b1, , bN} are the fitting coefficients which minimize the mean square (MS) prediction...

Ngày tải lên: 20/06/2014, 05:20

... allows the stall effect to be controlled The model of the pitch control system is based on the measured generator power (Pm) and the aerodynamic power (Paero) of wind turbine as a function of measured ... with the grid, i.e which influence the power Therefore only the drive train is considered in the first place because the other parts of the wind turbine structure have less influence on power The ... turbine, as can be seen in Fig 11 The blade angle control block models the active-stall control of the wind turbine based on the measured power and the reference one (Sorensen, P et.al, 2001) The...

Ngày tải lên: 20/06/2014, 05:20

... using the D and D-P methods The effects of WECS location on the system SI differ when using the P and D-P methods The MRTS with WECS located at Bus and Bus was used as the base system in the planning ... using the D and D-P methods The effects of WECS location on the system SI differ when using the P and D-P methods The MRTS associated with WECS located at Bus and Bus (Case 2) is considered as the ... using the D, P and D-P methods The WECS locations in the MRTS are considered in two cases: Case 1: the WECS are added at Buses and Case 2: the WECS are added at Buses and 4.2.1 Application of the...

Ngày tải lên: 20/06/2014, 05:20

... speed is the origin of the temporal variation of the power injected by this production type and thus has direct effects on the production-demand balance and the grid stability One of the challenges ... speed μh , the hourly standard deviation σh , the standard deviation σα of the {αt } process and the AR and MA coefficients φ1 φ4 and θ1 θ4 , respectively The output generated is the hourly ... loaded The transition conditions between the states are defined by the wind speed for the transitions between the On and Off states, and by the corresponding rates of the MTBF and MTTR in the case...

Ngày tải lên: 20/06/2014, 05:20

... simultaneously of these four factors: the aerodynamic efficiency, the mean efficiency, the use factor and the availability rate Conclusion This study has presented the development of the wind power use ... Weibull and Rayleigh functions (W/m²) Mean efficiency relating to the available energy Mean efficiency relating to the usable energy Mean efficiency Gearbox efficiency (96%) Generator efficiency ... speeds, and thus its efficiency decreases too, which happens in case when the wind energy is at its top Another drawback of the method is the necessary fine adjusting of the blades Wind Farms and Their...

Ngày tải lên: 20/06/2014, 05:20

... rotor swept area (m2), cp … power coefficient (-) which is dependent on the extent to which the rotor decreases the speed of the flowing air; the power coefficient has a theoretical maximum cpmax ... on the conservation of nature and landscape Therein, the face of the landscape is defined (§ 12) as a natural, cultural and historic characteristics of a particular site or region The face of the ... significant landscape elements, especially protected areas, cultural dominant features of the landscape, harmonic criteria and relations in the landscape Talking of the impacts on the face of the landscape,...

Ngày tải lên: 20/06/2014, 05:20

... Colorado has windy locations along the eastern border with Nebraska, Kansas, and Oklahoma.11 The general pattern of wind speeds from these state level wind maps provide the basis for the mean ... function, as this is the core basis for estimation of the resource Traditionally, the industry standard has been to model the PDF using either a Weibull or Rayleigh distribution It has been pointed ... particularly for the wintertime, this is theorized to be associated with a poleward shift of the mean thermal gradient as the earth warms and results in a northward shift of the associated storm...

Ngày tải lên: 20/06/2014, 05:20

... over the survey area and near environment, it has been planned and realized drilling (SK-1 on the middle of the base, SK-2 at the edge of the base) wells with 30 meter over the area at which the ... However, the contact and interaction of the superficial water and standing water which can accumulate during and after the construction of the foundations of the turbine as a result of the seasonal ... Estimation and Siting Assessment and after the excavation, and during and after the construction, it is required to protect the foundation area from the superficial waters and rains and adequate...

Ngày tải lên: 20/06/2014, 05:20