**7. Capacitor generic model**

The examination of the results obtained previously allows us to conclude that the equivalent radiating model for the different types of rectangular film capacitors is a rectangular loop whose parameters depend on the geometry of the capacitor as illustrated in **Figure 24** and explained in **Table 3**.

We suggest in **Table 3** formulas in order to determine by using capacitor dimensions the size of the source rectangular loop of the generic model.

To validate the proposed generic model, we applied it to another rectangular capacitor. Therefore, we measured the magnetic field above a third rectangular

**Figure 24.** *Capacitor parameters and the analogy with the equivalent loop.*

*Development of Generic Radiating Model for Rectangular Capacitors: Magnetic Near Fields… DOI: http://dx.doi.org/10.5772/intechopen.98894*


#### **Table 3.**

*Size of the source rectangular loop of the generic model.*

capacitor having 2.2 μF capacitance and a maximum voltage of 250 V (the capacitor size is 25 mm x 14 mm x 41.5 mm).

We performed measurements of the near field cartography above the studied capacitor, and then we applied the method based on the coupling of the electromagnetic inverse method with the MoM to find the equivalent model that will be compared to the one obtained by the generic model formulas.

According to **Table 4**, we notice that the calculated parameters by the formulas of the generic model are very close to those obtained by the inverse electromagnetic method.

We observe from the previous table that the searching model using the generic model is seven times faster than when being used without the generic model. Indeed, in the generic model, we search only one parameter (the excitation voltage), whiles the others parameters are calculated using the formulas given in **Table 3**.

**Figure 25** shows Hy and Hz's components of the magnetic near-field measured and estimated by the two obtained models above the capacitor under test at a frequency of 27 MHz.

According to the previous results, the magnetic field reconstructed using the proposed generic model shows an agreement with the measured magnetic field. In fact, in our modeling approach, we are interested in the high amplitudes of the magnetic field (red parts in the cartographies) because they have the most important magnetic field radiated by the component under test. We notice a good agreement between the measured and calculated fields by the generic model is observed.

**Figure 26** presents a comparison between the two models for cuts of Hz and Hy components along the x-axis. It shows a reasonable agreement between the measured magnetic field and the obtained one with the two models.


#### **Table 4.**

*Parameters of rectangular loop obtained by two methods.*

**Figure 25.** *Cartographies of magnetic field: (A) measured and (B) estimated using the inverse method and (C) using generic model (at 27 MHz).*

**Figure 26.** *Comparison of the two models for cuts of Hz and Hy components along the x-axis.*

*Development of Generic Radiating Model for Rectangular Capacitors: Magnetic Near Fields… DOI: http://dx.doi.org/10.5772/intechopen.98894*

The examination of all the obtained results enables us to conclude that the suggested generic model is a slight model that permits, in a very short time, the calculation of the radiation of the different types of rectangular capacitors.
