Tham khảo tài liệu 'electromotive force and measurement in several systems part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 170 Electromotive Force and Measurement in Several Systems Fig. 16. a 10 turns ring coil versus 50 turns planar coil at 3000 kHz b 15 turns ring coil versus 30 turns planar foil at 8000 kHz c 30 turns ring coil versus 500 turns planar coil at 1500 kHz d 50 turns ring coil versus 200 turns planar coil at 900 kHz. In this case the problem also presents higher gain when comparing with square wave excitation. Table 7 shows the gains of some inverted systems and Table 8 shows the gain ratio of these systems. Coil 10 12 20 30 50 10 20 50 200 500 Table 7. Gains of transformers with sinusoidal excitation inverted system columns with ring coil rows with planar coil. In Fig. 17 are shown the gain ratio of the inverted systems of Table 8. Comparing these curves with direct system presented in Fig. 14 we can see the similarity with the average gain ratio where only one system 10 turns ring coil versus 500 turns planar coil appears as a point out of what is expected. In this way both direct system and inverted system the gain appears almost higher when excited by a sine wave than excited by a square wave. However in both cases we can see Resonance Analysis of Induced EMF on Coils 171 that considering turn ratio that is ideal gain transformer at resonance the gain does not satisfy coupled circuit theory. This effect of EMF in secondary transformers when resonance is reached is interesting phenomenon that shows new perspectives for this area. Due to these analyses several researches can be realized from resonance applying this special transformer and obtained data and results to new technologies. In this way researches about induced EMF in cascaded direct systems and inverted systems to reach high output voltages and others are optimal perspectives as well their applications. Coil 10 12 20 30 50 10 20 .
