current three phase self cooled ratings

... TECHNIQUES FOR THREE- PHASE VS-PWM CONVERTERS While phase voltages can be controlled independently, phase currents are determined not only by their own phase voltage, but also by those of other phases ... midpoint (when available) phase load are not connected [Fig 2(a)], phase currents depend only on the voltage difference between phases Therefore, a common term can be added to the phase voltages, thus ... system with three independent controllers The comparator state change in one phase influences the voltage applied to the load in two other phases (coupling) However, if all three current errors...

Ngày tải lên: 03/01/2014, 19:45

... transformers required to build (single -phase two-winding) (three- phase two-winding) (single -phase three- winding and single -phase two-winding) (single -phase three- winding) Vl V √l Vl V √l : √ : ... are used only for neural current compensation Compensation of neutral current along with elimination of phase harmonic currents can be done by incorporating a three- phase, three- wire APF to the ... suppressor in three- phase four-wire systems, IEEE Trans Ind Electron 54 (2007) 2201–2208 [34] H.-L Jou, K.-D Wu, J.-C Wu, W.-J Chiang, A three- phase, four-wire power filter comprising a three- phase three- wire...

Ngày tải lên: 11/05/2014, 22:06

... determine the amount of current flowing through the coils, a shunt resistor is required on each coil A typical three- phase inverter with current measurement on three phases is shown in Figure ... VECTOR AREAS TO RECONSTRUCT THREE- PHASE CURRENTS USING A SINGLE-SHUNT RESISTOR V1 I V2 VI II V6 V T2 V3 III IV V5 T1 V4 In general, single-shunt reconstruction of three- phase currents is not possible ... well (not currently shown, but assuming PWM outputs are complementary) Since there is current flowing into the motor through phases A and C, and coming out of phase B, we can consider this current...

Ngày tải lên: 11/01/2016, 17:06

... rotor flux, rho The calculated three- phase sinusoidal current values are then compared with the measured stator currents The three- phase error currents are then fed into current controllers These ... unknown current magnitude: = Ia + Ib + Ic (3.1) Where Ia, Ib and Ic are the three- phase stator currents 2001 Thesis Project A11 Gareth S Roberts However, application of an effective current sensing ... in Chapters and 3.3 Current sensing module The implemented current- sensing module consists of two current transducers Because the stator windings of the motor are a three- phase wye connection,...

Ngày tải lên: 27/10/2013, 23:15

... 3 -phase AC motor with three phase windings u, v and w The three phase voltages are applied by three pairs of semiconductor switches vu+/vu-, vv+/vv- and vw+/vw- with amplitude, frequency and phase ... magnetizing current running through Lm Vector of magnetizing current dq components of the magnetizing current Vectors of grid, transformer and filter current Vector of stator, rotor current dq ... voltages and currents Fig 2.5 Pulse frequency fp and the influence on the stator voltage as well as the stator current 1: Pulsed phase- to -phase voltage; 2: Fundamental wave of the voltage; 3: Current...

Ngày tải lên: 18/12/2013, 09:10

... 1,3,5 0 2,4,6 Table Phase voltage space vectors State Phase voltage space vectors 12/ 3) Vdc / (101) Figure Phase voltage space vectors -(2/3) VdC '(100) Real (001) Table Phase voltage values ... used for reference voltage generation when current control is exercised in rotating reference frame It is seen in the previous section that a three- phase VSI generates eight switching states ... vector is a simultaneous representation of all the three- phase quantities It is a complex variable and is function of time in contrast to the phasors Phase- to-neutral voltages of a star-connected...

Ngày tải lên: 24/12/2013, 11:32

... Space-Vector PWM Current Regulator for Three- phase Power Converters”, IEEE Trans on Power Electronics, vol 13, NO 3, May 1998 pp419-426 M.-T Tsai, W I Tsai: “Analysis and design of Three- phase AC-to-DC ... output voltage and load current I I So, the current reference depends on both load power and output voltage error as shown in Fig This current value is used as reference for a current controller such ... load current that can be delivered is obtained [2]: IL" 3E2 =4RVo Unfortunately, the three- phase converter must be able to impose the energy exchange and to fulfil the constraints on the input currents...

Ngày tải lên: 03/01/2014, 19:44

... Fig3(b) shows the waveform of u -phase supply current is,, which is the sum of currents i, and i in Fig.3(a) , The current is, has a distorted waveform caused by the current i,, Next, the operation ... The current i, has a distorted waveform because it contains compensating currentcomponents corresponding to the harmonic currents mentioned above FigA(b) shows the waveform of u -phase supply current ... rectifier input currents i, , iv and Active Filtering Operation For active filtering operation, the P W M rectifier is 387 i,, PWM signals SI,, S, and S , for phase U, phase v and phase w , respectively,...

Ngày tải lên: 03/01/2014, 19:44

... "Dead Beat Control of threePhase PWM Inverter", IEEE Transactions on Power Electronics, Vol 5, No 1, January 1990, pp 21-28 [3] Osman Kükrer, "Deadbeat Control of a Three- Phase Inverter with an ... principle of the current control loo f op Since the inv verter must q quickly supp the load current IL to compensate the disturbance of the l ply o e load, the predictio of the load current is implemented ... F contains the current loop, volt nor tage major lo oop, the DC link referen estimatio C nce on and the DC link voltage control loop Here only a brief desc a p y cription of th current an voltage...

Ngày tải lên: 19/01/2014, 02:20

... a -phase current becomes greater than the reference current plus the hysteresis level h, the lower transistor of the a -phase leg is turned on, which tends to reduce the current If the a -phase current ... drop vd If the upper switch is on and the phase current is zero, it seems Figure 12.2-2 One phase leg THE THREE- PHASE BRIDGE CONVERTER 463 Figure 12.2-3 Phase leg equivalent circuits (a) Upper ... switch current, it can often be represented as a constant From Figure 12.2-3a, the dc current into the bridge, ixdc, is equal to the phase current ixs If the upper transistor is on and the phase current...

Ngày tải lên: 16/02/2014, 18:53

... modified by current public health policy Current SEIs reflect current socioeconomic conditions Modification is feasible, although in many resource-poor situations it may be impractical Current 343 ... categories, we modeled self- reported health status in three categories: poor or fair, good, and very good or excellent an outcome with three or more ordered categories (in our case we used three categories ... The effect of selected current socioeconomic indicators on better self- reported health status among 147 elderly persons in study of historical and current predictors of self- reported health status,...

Ngày tải lên: 14/03/2014, 20:20

... rV =rtrue Viscosity of the gas phase, NÁs/m2 Viscosity of the liquid phase, NÁs/m2 Molar mass of gas, kg/mol Density of the gas phase, kg/m3 Density of the liquid phase, kg/m3 Feed time in unsteady-state ... by compressor The two -phase gas–liquid mixture passes heat recuperator 8, where it is heated by the hot flux leaving the reactor The finish L B Datsevich, Conventional Three- Phase Fixed-Bed Technologies, ... Passing the reactor, the gas–liquid flow is consecutively cooled in recuperator and cooler The comparatively cold two -phase mixture enters phase separator 4, from which the liquid product (with...

Ngày tải lên: 16/03/2014, 22:20

... fibre, three- phase composite is more heatproof than two - phase composite Calculated results of this material also indicate that when increasing volume fraction of glass particle phase, three- phase ... coefficients of three- phase composite material more than that of two - phase composite material in [7] So, embedding spherical inclusions into continous matrix phase of two - phase fiber composite ... expansion coefficients of three- phase composite material reduce Conclusions Based on the idea solving the problem of three- phase composite material through problems of known two - phase composite material,...

Ngày tải lên: 28/03/2014, 13:20

... calculated result for three- phase composite, considering the interaction between nano seeds and the supposed matrix) Fig Calculated result for Moduli K of the two-phases and three- phases composite ... 60oC [8,9] The model of the three- phase composite in this paper, therefore, include: polyme matrix, reinforced pad seeds and nano seeds (Fig 1) Fig Model of the three- phase composite We approach ... From this supposition, the three- phase composite problem will be solved according to two -phase model with algorithm as follows: at first, the constants of the two -phase composite material which...

Ngày tải lên: 28/03/2014, 13:20

... load conditions the three phase currents will be equal, as will be the three line currents If the load is unbalanced, then these equalities not exist, and each phase or line current would have ... stator of a three- phase machine is utilised A single phase alternator utilises only two thirds of the stator slots A three- phase alternator has a better distribution factor A three- phase, four-wire ... from a single -phase machine A three- phase supply produces a rotating magnetic field; whereas a single -phase supply produces only a pulsating field Three- phase motors are inherently self- starting;...

Ngày tải lên: 03/04/2014, 20:52

... COMMISSION _ SHORT-CIRCUIT CURRENTS IN THREE- PHASE AC SYSTEMS Part 3: Currents during two separate simultaneous line-to-earth short circuits and partial short-circuit currents flowing through ... IEC:2003 11 SHORT-CIRCUIT CURRENTS IN THREE- PHASE AC SYSTEMS Part 3: Currents during two separate simultaneous line-to-earth short circuits and partial short-circuit currents flowing through ... 5.1.2 Peak short-circuit current, symmetrical short-circuit breaking current and steady-state short-circuit current 23 5.1.3 Distribution of line-to-earth short-circuit currents during two...

Ngày tải lên: 04/04/2014, 11:58

... Electronics Association [4] Lászó Huber and Dusan Borojevic, “Space vector modulated three- phase to three- phase matrix converter with input power factor correction” IEEE Transactions On Industrial ... KimB.Larsen, Allan Holm Jorgensen, StigMunkNielsen, “Evaluation of Modulation Schemes for Three- Phase to Three- Phase Matrix Converters” IEEE Transactions On Industrial Electronics, Vol.51, No.1, February ... Member, IEEE, and Frede Blaabjerg,Fellow, IEEE, “Evolution Of Modulation Schemes For Three- Phase To ThreePhase Matrix Converters” IEEE Transactions On Industrial Electronics, Vol.51, No 1, February...

Ngày tải lên: 14/05/2014, 22:37

... theory of a three- phase stator, raises the following issues of concern: (1) It was reported by Kovacs in [7] that a current flowing through a stator phase winding produces a related current vector ... axis, but no proof was given for this equality (3) The current vectors produced by each phase winding of a three- phase, two-pole stator, whose phase windings were separated from each other by 120 ... dt (5) where, vb , i b and λb are the scalar phase supply voltage, scalar phase current and scalar phase flux linkage respectively and Rb the stator phase resistance for winding b Eq (5) was then...

Ngày tải lên: 26/10/2014, 14:40