*5.3. Loss Model*

The induction motor simulation in [24] centres on an experimental three-phase stator and rotor circuit design using a magnetic coupling in the intermediate stage, thus neglecting core loss. As seen in Figure 3a, the concept serves as the backbone for major vector control derivations and a design based on the study of an electric drive. The stator-side resistance, leakage inductance, and mutual inductance [25] are denoted as *RS*, *LlS*, and *Lms*. *R r*, *Llr* , and *Lmr* are the rotor-side resistance, leakage inductance, and mutual inductance, respectively, as with the stator side. The flux on each rotor or stator circuit is divided into the leakage and mutual components because solely the former reaches the magnetic connection field with which the stator and rotor interface. Figure 3b depicts a conventional steady-state per-phase circuit diagram, which takes core loss into account as the energy lost in *rc*\_*ph*. *Lm* is the steady-state magnetising inductance corresponding to (1.5 × *Lms*). It should be noted that the connection impacts of other phases are summed into *Lm* which is acquired from steady-state observations. As a result, the diagram is entirely irrelevant for transient applications [26]. Figure 4 depicts the suggested induction machine design, which is influenced by the preceding two conventional designs. The core loss is understood as a resistor *Rc* in parallel with *Lms* in each stator phase. It should be noted that *Rc* is not equivalent to *rc*\_*ph*, although they were associated in [27].

**Figure 3.** (**a**) The classical induction machine model considers only copper loss; (**b**) the steady-state per-phase equivalent circuit [27].

**Figure 4.** Loss model of an induction motor [27].
