1. High-Phase-Order Induction Generators for Electric Ships Tom McDermott, tem42@pitt.edu Parviz Famouri, parviz.famouri@mail.wvu.edu Woody Polter, sherwood.polter@navy.mil ASNE Day 2015; March 4, 2015 1.Advantages – (no) permanent magnets, cost, reliability 2.How it fits the integrated power system 3.Analysis of voltage and frequency control 4.Start-up performance in transient simulation 5.Machine and controller design questions

2. U. S. production of rare earths had been shut down, but went up to 4000 metric tons in 2013. 3/4/2015ASNE Day 2015: HPO-IG2

3. Induction generators and six-phase transmission lines have been used and tested. 3/4/2015ASNE Day 2015: HPO-IG3

4. High-phase-order induction generators work for both AC and DC power distribution systems. 3/4/2015ASNE Day 2015: HPO-IG4

5. The DC system voltage has less ripple when supplied through an 18-pulse rectifier. 3/4/2015ASNE Day 2015: HPO-IG5

6. The self-excited induction generator operates in resonance, where the sum of impedances around the loop is zero. 3/4/2015ASNE Day 2015: HPO-IG6

7. The machine’s non-linear saturation characteristic determines the operating point. 3/4/2015ASNE Day 2015: HPO-IG7

8. Fine-grain control of the voltage and frequency is possible. 3/4/2015ASNE Day 2015: HPO-IG8

9. When the prime mover runs at constant speed, the voltage and frequency both decrease with load. 3/4/2015ASNE Day 2015: HPO-IG9

10. Thyristor switched capacitors provide step-wise control without switching transients. 3/4/2015ASNE Day 2015: HPO-IG10

11. TSC voltage results with 31 and 63 capacitor levels. 3/4/2015ASNE Day 2015: HPO-IG11 5 steps, 31 levels. 6 steps, 63 levels.

12. 9-phase, saturable induction machine model in IEEE Std. VHDL-AMS language supports transient analysis. 3/4/2015ASNE Day 2015: HPO-IG12

13. Generator starts with full-load capacitance value; 36- MW load switches on at 3 seconds. 3/4/2015ASNE Day 2015: HPO-IG13

14. Conclusion – the HPO-IG offers advantages for naval applications, if some questions can be answered. Advantages – No permanent magnets – Multi-phase motors with better torque performance – Enhanced reliability after losing one or more phases Questions – How many phases? – Providing the initial flux for self-excitation – Reactive power controller – AC or DC architecture – Machine speed and saturation characteristic 3/4/2015ASNE Day 2015: HPO-IG14