2.2. Assumptions for the ac-dc/dc-dc power converters

The uninterrupted conduction is taken into account (a high value for the additional armature inductance is designed), the conduction droop voltage on the power semiconductors and the switching time are negligible.

Hfnð Þ¼ s

The corresponding Simulink block diagram is shown below in Figure 3.

where TFn is the time constant of the speed transducer.

imposed performances for the inner closed loop are:

c. phase margin of the current loop: γ = 63�26<sup>0</sup>

loop transfer function of the inner loop has the form:

Figure 3. Simulink block diagram of the dc drive system.

a. null steady state error εst = 0;

a. current overshoot, σ = 4.3%;

I. the steady state regime:

II. the dynamic regime:

armature time constant:

1 1 þ sTFn

Matlab-Simulink-Based Compound Model Reference Adaptive Control for DC Motor

The control design procedure starts with the armature current loop design (inner loop). The

b. the rejection of the perturbation influence (load torque is the main perturbation).

In order to satisfy the above mentioned performances the modulus criterion is used. The Kessler criterion guarantees of the above mentioned performances on condition that the open

where, TΣ<sup>I</sup> – the parasitic time constant of the current loop is considerably lower than the

.

1 2sTΣ<sup>I</sup>ð Þ 1 þ sTΣ<sup>I</sup>

TΣ<sup>I</sup> ¼ TFI þ TTI << TA (4)

b. response time depends on the cutting frequency of the loop: tr = 2.35/ωcI;

HcutIð Þ¼ s

, (2)

http://dx.doi.org/10.5772/intechopen.71758

(3)

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### 2.3. Assumptions for the load

The load torque is considered as mathematical model of the process, the load is reduced appropriately to the dc motor shaft (by using both equivalent inertia moment and reduced equivalent speed by taking into account the specific transmission ratio).
