## 6 Experimental Results
### ITSCF Diagnosis Results  
In the practical fault diagnosis of IPMSM, this study employs an innovative energy percentage method (40) for the application diagnosis of actual motor products, aiming to expand the effective application of the research methodology. By calculating the proportion of energy from each frequency range and the reconstructed signals, visual indicators are obtained for error characteristic assessment, enabling the final results to reveal the differences between healthy motors and ITSCF. The energy percentage analysis results under steady-state operating conditions at 1500 rpm are shown in Figure 26. It can be observed that the D\({}_{5}\) value for ITSCF is higher than that of the healthy condition. The energy percentage data for each frequency range in Figure 26 are further organized in Table 3. The D\({}_{5}\) percentage for ITSCF is 15.3%, while the D\({}_{5}\) percentage for the healthy condition is 4.5%. This confirms the effective applicability of the DWT and IDWT methods proposed in this study for detecting ITSCF characteristics. To validate the effectiveness and practicality of the proposed IPMSM inter-turn short-circuit fault feature extraction framework, a comparative analysis using FFT on \(V_{q}\) is conducted to demonstrate the superiority of the proposed method. As shown in Figure 27, the \(V_{q}\) component of the ITSC motor exhibits a second harmonic frequency of approximately 200 Hz, with an amplitude approximately 2.5 times that of the healthy motor. This characteristic second harmonic component can serve as a distinctive fault feature for ITSC diagnosis. Further analysis reveals that the synchronous \(V_{q}\) information can also show fault characteristics through FFT. However, in practical applications, due to issues such as rotational velocity errors and external environmental interference, directly observing the amplitude at specific FFT frequencies may lead to misjudgments. Therefore, it is confirmed that the method proposed in this study, which observes and analyzes the energy percentage within the DWT frequency ranges, is still superior to the application of FFT. Furthermore, the FFT analysis results corroborate the trends observed in the DWT analysis, thereby validating the effectiveness and field applicability of the proposed DWT-based approach for practical applications. In addition to the aforementioned experimental comparisons, the experiment was also conducted at 600 rpm for comparative analysis. Under the test condition of 600 rpm, the twice-electrical frequency is approximately \(f_{e}\) = 80 Hz, with a sampling rate of \(f_{s}\) = 10 kHz. Given the 80 Hz characteristic frequency, which lies at the boundary between the A\({}_{6}\) and D\({}_{6}\) frequency bands, as illustrated in Table 2, it is imperative to adjust the sampling rate to prevent the feature from being dispersed across two different frequency bands. Therefore, the DWT frequency ranges for 600 rpm are calculated based on Equation (27), as shown in Table 4. The energy percentage analysis results under steady-state operating conditions at 600 rpm are shown in Figure 28, where it can be directly observed that the D\({}_{7}\) value for ITSCF is higher than that for the healthy condition. The energy percentage data for each frequency band in Figure 26 is further organized in Table 5. The D\({}_{7}\) percentage for ITSCF is 10.2%, while the D\({}_{7}\) percentage for the healthy condition is 4.1%. This result is also consistent with the ITSCF characteristics derived in Section 3. As shown in Figure 29, the \(V_{q}\) component of the ITSC motor exhibits a second harmonic frequency of approximately 80 Hz, with an amplitude approximately three times that of the healthy motor. As shown in Tables 3 and 5, the energy percentage of the second harmonic component (approximately 200 Hz at 1500 rpm and 80 Hz at 600 rpm) within the corresponding DWT frequency bands (156-315 Hz and 58-117 Hz, respectively) is significantly higher for ITSC motors compared to healthy motors.