# Research on the High Reliable Electromagnetic Stirring Power Supply
## 3 Results and Discussion
### Experiment and Analysis  
The reconstructed topology of high-reliability electromagnetic stirring power supply and the control algorithm are applied to the electromagnetic stirrer for experiments. The grid voltage is 380 V, 50 Hz. The filter inductance on the grid side is 1 mH. The DC side capacitance value is 5000 \(\upmu\)F. The DC side voltage is 400 V. The inverter output side filter is 0.5 mH. The equivalent inductance of the electromagnetic stirrer is 50 mH, and the equivalent resistance is 0.5 \(\Omega\). This article uses Case 2 in Table 1 as an example for experimental verification. The experimental results are shown in Figures 13-15.  
Figure 11: Faulty V\({}_{1}\) and V\({}_{2}\) at t = 0.5 s. (a) faulty signal of V\({}_{1}\); (b) faulty signal of V\({}_{2}\); (c) Output currents; (d) power factor.  
Figure 12: Faulty V\({}_{1}\) and V\({}_{4}\) at t = 0.5 s. (a) faulty signal of V\({}_{1}\); (b) faulty signal of V\({}_{2}\); (c) Output currents; (d) power factor.  
Figure 13a,b are the waveforms of three-phase output currents and the corresponding DC side voltage of the normal working conditions for the forward-stop-reverse operation.  
Figure 14: Experimental results in the faulty operation without reconstructing topology. (**a**) the output currents; (**b**) the DC side voltage.  
Figure 15: Experimental results in the faulty operation with reconstructing topology. (**a**) the output currents; (**b**) the DC-side voltage ; (**c**) the output currents in the forward operation; (**d**) the DC-side voltage in the forward operation; (**e**) the output currents in the reverse operation; (**f**) the DC-side voltage in the reverse operation.  
The three-phase output currents are completely consistent with the given currents, and the DC side voltage is stable without fluctuations. Figure 14a,b are the waveforms of \(\alpha\)-phase output current and the corresponding DC side voltage of the fault working conditions without reconstructed topology for the forward-stop-reverse operation. The output current is distorted, and the amplitude and phase of the given current waveform cannot be tracked at all, and the DC side voltage also fluctuates. Figure 15a-f are the waveforms of the three-phase output currents and the corresponding DC side voltage of the fault working conditions and reconstructed topology for the forward-stop-reverse operation, the three-phase output current and the corresponding DC side voltage for forward running condition, the three-phase output current and the corresponding DC side voltage for reverse working operation. From Figure 15a-f, it can be seen that, regardless of whether the electromagnetic stirrer is agitated forward or reversely, the three-phase output currents of the inverter can be consistent with normal operation, which can maintain a smooth sine wave and correctly follow the given currents. The DC side voltage remains stable. Therefore, the problem of stable control of the high-reliability electromagnetic stirring power supply is solved. The switching of forward-stop or stop-reverse stirring can be maintained fast. The experimental results verify the validity of the fault diagnosis algorithm, the correctness of the reconstructed topology and the fault-tolerant control strategy proposed in this paper.