## 4 Results and Discussion
### Multi-Microwave Sources Collaborative Switching Heating
The heating effect of SiC under different switching strategies in the multi-microwave sources system is shown in Figure 9.  
Table 4 shows that the multi-microwave sources system maintains unchanged power fed into the cavity. Compared with constant power heating, eight different heating strategies have improved the uniformity of material temperature. The heating time for SiC in experimental groups (b-e) decreased from 32 s to 20 s, and the single source high-power state \(P_{2}\) increased from 475 w to 700 w. Among them, the microwave utilization efficiency of switching strategy (c) reached 53.7%, which is 7% higher than that of constant power heating; the switching strategy (e) results in a more uniform temperature distribution of SiC, with a 43.6% improvement in temperature uniformity compared to constant power heating, the overall temperature difference of the heated SiC material is \(\delta T=\)15.502 \({}^{\circ}\)C, which is the lowest. The uniformity of material temperature may be affected to improve the efficiency of microwave energy utilization. The experimental group (f-i) has heating cycles of 20 s, 10 s, 8 s, and 5 s, respectively. The single source high-power state \(P_{2}\) is fixed at 700 W. When maintaining uniform SiC heating temperature, switching strategy (f) has the highest microwave utilization efficiency, the energy utilization efficiency increased by 10.7% compared to constant power heating. The experimental group (f-i) used higher microwave power, which caused a faster temperature rise, resulting in greater microwave energy utilization efficiency than the experimental group (b-e). When the total power remains constant, the energy input of the experimental group (f-i) is quickly concentrated, decreasing the uniformity of material temperature. High and low power complementarity and the self-organizing characteristics of material temperature can be utilized to suppress the generation of hotspots. To achieve better microwave energy utilization efficiency, sacrificing some uniformity in material temperature may be necessary. Figure 9: Heating effect of SiC under different switching strategies in the multi-microwave sources system. (**a**) Heating effect of SiC under the Multi-microwave sources constant power strategy. (**b–i**) Heating effect of SiC under the multi-microwave sources collaborative switching heating strategies (methods of (**b–i**) in Figure 8). In order to further emphasize the effectiveness and universal applicability of the multi-microwave sources collaborative switching heating strategy described in this article, we carried out four comparative heating experiments on potatoes based on reference [16; 29], while keeping the total power supplied to the cavity constant:  
1. Multi-microwave sources constant power strategy. The output power of six microwave sources in the experiment was set at 200 W.
2. Multi-microwave sources consistent variable power (method of [29]). Inspired by reference [29], the microwave output power in the multi-microwave sources system varies over time, the output power curves of six microwave sources are set at \(p_{i}(t)=200(\sin(0.2\pi t)+1)\). 3. Group switching consistent variable power (method of [16]). The power output of the microwave varies over time. Following the example in reference [16], the power output curves for microwave sources 0, 3, and 5 are set to \(p_{i}^{1}(t)=50(\sin(0.2\pi t)+1)\) W, while the power output curves for microwave sources 1, 2, and 4 are set to \(p_{i}^{1}(t)=150(\sin(0.2\pi t)+1)\) W.
4. The multi-microwave sources collaborative switching heating strategy (our method).