Engineering and Scientific Computations Using MATLAB phần 10

Giải pháp. Sử dụng phương trình vi phân, người ta phải xây dựng các sơ đồ simulink. Từ phương trình vi phân khối đưa ra ở trên, chúng ta có được các thiết lập của phương trình sau đây được sử dụng trong mô hình | Chapter 6 S1MULINK 196 Solution. Using the differential equations one must build the Simulink block diagram. From the differential equations given above we obtain the following set of equations to be used in the Simulink mdl model digs 1 r 1 z r 4-rCOSff- J dli brCo dr d crCo dr dt Lls Lms s as 2 ms dt 2 ms dt ms dt ms dt ms dt as dibs 1 . 2r . 1 r r d cohr J d ihrcosớr d i rrcoỉịớr ĩf dt 4 Ảm _ sbs 2 ms dt 2 ms dt ms dt ms dt ms dt bs dies 1 . di .tj r dỊi arco r ĩf d ihrco r- f d i r cosớrỊ dt 4 4 scs 2 ms dt 2 ms dt ms dt ms dt ms dt digr 1 d iascos0r d ịhscữ er- d ịcscữ er À dicr . dt Llr Lms rar ms dt ms dt ms dt 2 ms dt 2 ms dt ar di br _ 1 r d iÍÌSco ỡr d ịhscosỡr d icscoẶỡr- r dL di cr . dt Llr Lm rhr ms dt ms dt ms dt 2 ms dt 2 ms dt br die A _ 4 - f 4 CO4- f cosflr . dLlj di i dt Llr Lms rcr ms dt ms dt ms dt 2msdt 2 sdt ucr To guarantee the balanced operating condition the following phase voltages should be applied to the induction motor windings Mữí O Wji cos iyzz . 0 V2 a cos fflz -ịx ucs JĩuM cos iyft ịĩĩ . The Simulink block diagram to simulate three-phase squirrel-cage induction motors is developed and illustrated in Figure . The Derivative blocks are used. Chapter 6 Simulink 197 Figure . Simulink block diagram to simulate squirrel-cage induction motors c6_2_4 .mdl Chapter 6 Si MU LINK 198 Angular velocity wr rad sec The induction motor parameters rs ohm rr ohm Lms H Lis H Llr H J kg-m2 and Bm N-m-sec rad are downloaded. In particular in the Command Window the designer inputs the motor parameters as p 2 Rs Rr Lms o7o35 Lls Llr Bm J Nonlinear simulations were performed and transient dynamics of the stator and rotor currents in the as bs cs ar br and cr windings ias f Crtf 4-0 and C 0 as well as the rotor angular velocity are documented in Figures and . The statement to plot the evolution of a rm t is plot wr 1 wr 2 xlabel .1 Time seconds title Angular velocity wr .