single phase induction machines the basics

... two -phase induction motor with the impedance of the start winding larger than that of the run winding The asymmetry of the stator windings causes the winding currents to be 359 SINGLE- PHASE INDUCTION ... on Although the brushless dc machine is starting to be used in some of these applications, the single- phase induction motor remains in wide use As we have mentioned, the single- phase induction ... it appear that the split -phase machine is the type of two -phase machine that is used in single- phase applications, this is not the case In fact, symmetrical two -phase induction machines are often...

Ngày tải lên: 16/02/2014, 18:48

... The arrangement was good for all of them The time had ¢nally come to confess the The audience stared at the screen, truth fascinated by the action they were seeing He’s the boy who delivers the ... nouns Those on the left use the; those on the right not a The United States Great Britain The Netherlands France b The Holy See Holy Cross University c The Jolly Green Giant Big Foot d The Bronx Manhattan ... noun Compare these nouns to *the very, *the walked, *the because.Very, walked, and because are not nouns While you can easily put the and very together (for example, the very tall boy), the very,...

Ngày tải lên: 17/08/2013, 10:39

... returns the square of x z = x.ˆ2; Typing sq(3) produces the answer 9, whether or not x or z is already defined in your Workspace, and neither defines them, nor changes their definitions, if they have ... preceded by the special symbol @ (as in ode45(@func, [0 2], 1)) The @ syntax is new in MATLAB 6; in earlier versions of MATLAB, the substitute was to enclose the name of the function in single quotes ... int(h(t), t) ans = 1/4*t^4 56 Chapter 4: Beyond the Basics then the previous definition of h is substituted into the symbolic expression h(t) before the integration is performed Substitution In Chapter...

Ngày tải lên: 29/09/2013, 19:20

... on the theory behind the operation of an induction motor The three -phase induction machine is presented in Chapter 13 The electromagnetic and mechanical phenomena that are responsible for the induction ... 6.2.2 The Current Controller The primary purpose of this block is the to regulate the voltage signal applied to the induction motor The phase currents measured from the feedback portion of the ... Furthermore, the encoder generates two pulses, A and B, which will allow the DSP controller to detect the direction of the rotor; the B pulse lags the A pulse by 900 in the positive direction The...

Ngày tải lên: 27/10/2013, 23:15

... transferred from the customer's account to the retailer's account The customer inserts her/his card into the chip and PIN keypad The payment is authorised The PIN is verified The cashier scans the barcodes ... Number the following in the correct order The transaction appears on the customer's bank statement The customer arrives at a supermarket checkout The card's electronic chip is read, and the customer ... Unit 0000 A Match the formal phrases on the left with the informal phrases on the right I deposited some money a The money's been sent I withdrew some money b I paid in some money The funds have...

Ngày tải lên: 02/11/2013, 10:20

... are collecting their data o how we plan to use their data o what data we have about them o that the data may be transferred to the U.S or other countries o how they can remove themselves from ... to use this information for any other purpose than to carry out the services they are performing for P&G Consumer Consent • • • Consumers must consent to have their data collected Consumers should ... that we would like to use their data for a specific purpose (e.g marketing or follow-up) o when consumers' data will be transferred o and that the choice belongs to the consumer Children’s Privacy...

Ngày tải lên: 12/12/2013, 00:15

... using three -phase AC machines From the principles of electrical engineering it is known that the 3 -phase quantities of the 3 -phase AC machines can be summarized to complex vectors These vectors ... yq of the current controllers RI If the field angle ϑs between the axis d or the rotor flux axis and the stator-fixed reference axis (e.g the axis of the winding u or the axis ) is known, the components ... protection time tD The actual voltage uv of phase v The voltage errors Δuv The influence of tD on the trajectory of the stator voltage vector us as well as on the fundamental wave of the phase voltage...

Ngày tải lên: 18/12/2013, 09:10

... when the shoot-through zero vectors are taken, the load is shorted by the upper and lower switches at the same phase leg These zero vectors are allowed in the Z-source inverter, whereas they ... loop, respectively, where ζi is the damping ratio and γi is the phase margin It can be seen that the step response of the inner loop meets the criteria when the gain of the proportion controller is ... are suggested as the criteria to evaluate the tracking performance of the inner loop [26] Tables II and III show the parameters in the simulation model and the step response of the inner loop,...

Ngày tải lên: 03/01/2014, 19:12

... normal operation of induction machines is in the range 10% to 2% for induction machines with power ratings in the range kW 100 kW The value of the slip that corresponds to the rated operating ... rotation of the rotor The induced emf exists in each stator phase and it holds balance to the applied stator voltage Following the same approach as for the rotor phase, one can immediately write the ... detached from slip rings This is the normal operating state of a slip-ring induction machine The second type of induction machines are so-called squirrel-cage induction machines Rotor winding is in...

Ngày tải lên: 23/01/2014, 06:20

... Fig 6.9 shows the single- phase equivalent circuit Figure 6.9 Single- phase equivalent circuit for a polyphase induction motor §6.4 Analysis of the Equivalent Circuit The single- phase equivalent ... Currents and Fluxes in Polyphase Induction Machines §6.3 Induction- Motor Equivalent Circuit Only machines with symmetric polyphase windings exited by balanced polyphase voltages are considered ... in the form ⎠ T = − KI r sin δ r (6.6) I r : the rotor current δ r : the angle by which the rotor mmf wave leads the resultant air-gap mmf wave Fig 6.4 shows a typical polyphase squirrel-cage induction...

Ngày tải lên: 14/02/2014, 16:37

... machine If, on the other hand, the external rotor circuits are unbalanced but the applied stator voltages are balanced, then the reference frame fixed in the rotor is most convenient Either the stationary ... INDUCTION MACHINES The torque and rotor speed are related by ⎛ 2⎞ Te = J ⎜ ⎟ pω r + TL ⎝ P⎠ (6.3-8) where J is the inertia of the rotor and in some cases the connected load The first term on the ... note that the waveform of the torque is the same regardless of the speed or the change in the speed of the reference frame 6.12 DYNAMIC PERFORMANCE DURING SUDDEN CHANGES IN LOAD TORQUE The dynamic...

Ngày tải lên: 16/02/2014, 18:47

... grandmothers as the appropriate source for the intervention The grandmothers who participated in formative research developed the chitterlings cleaning method for their peers Having the grandmothers ... outline of the phases in the social marketing process, including questions to ask and items to consider during the process The six phases of the planning tool are outlined in detail on the CD-ROM ... offering the audience benefits they want in return for making the desired behavior change For example, you give them a sense of being cool and accepted by their peers if they give you themselves...

Ngày tải lên: 18/02/2014, 02:20

... observed across the different studies as well as the similarity of the recognition sites of the NFAT and Ets factors led us to investigate the potential involvement of the epithelial specific ... reduces activation of the COX-2 promoter by ESE-1 and by LPS To examine whether the Ets sites in the COX-2 promoter are responsive to ESE-1 and to determine whether LPS induction of the COX-2 promoter ... transcription factors as the mutation of the CRE site within the COX-2 promoter or the expression of a dominant negative mutant of CREB reduces inducibility of the COX-2 promoter [9,12–14] The transcription...

Ngày tải lên: 19/02/2014, 17:20

... per day? Could they make one per day by writing their name on it? They could There are loads of other ways of both saving the company money and respecting the planet Brainstorm them 91 Be fast ... PPT slides The ones shown at every pitch Are they for real? Or they pitch a fantasy that no customer has ever experienced Make sure the gap between the story told at the pitch and the real experience ... Work from the shop floor Do a day behind the counter on the phones or on the cold garage floor Yep; maybe their job isn’t so easy after all… 82 Don’t despise Starbucks Observe how they have optimised...

Ngày tải lên: 06/03/2014, 19:20

... evidence for the importance of the hexagonal phase forming tendency of the membrane The two di-18:1-acyl-PtdEtn, Ole2PtdEtn and Ela2PtdEtn, differ only in their conformation of the double bond, ... demonstrated by the ratio of the formation rates of the two diol-epoxides, DE2 and DE1 These differ only in the conformation of the 9,10-epoxy-group, anti in DE2 and syn in DE1 The respective ... profile, i.e they not alter the stereoselectivity of epoxidation Obviously, there is no alteration of the active site conformation of P450 But the striking parallelism of the curves in the Lineweaver–Burk...

Ngày tải lên: 08/03/2014, 10:20