Hitachi has developed a generating system based on the new concept in order to prevent being worse of turbine performance by vaiable speed system. It is ideal for small hydro power generation.
System Configuration - Simple but new -
Verification in combination with 30kW model turbine
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Controlled speed operation from generator side |
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Largely reduce inrush current from induction generator |
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Our own method can control higher harmonic wave caused by diode rectifier. |
![[Image]Testing facility](images/p005_03.jpg)
Testing facility ( 30kW )
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Waveform of inrush current
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At secondary short circuit Cage
type induction generator
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secondary opening
This system
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Water flow at head variation
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At low speed whirling,
low performance
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At controlled speed operation
Optimum condition without whirl
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Simulation |
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Fixed speed system |
Controlled speed inductoin system |
| Turbine output |
from 56m to 104m |
| Turbine output |
1,900kW |
| Rotating speed |
720r/min |
from 620 to 800 r/min |
| Yearly generating electric power |
100% |
104% |
| House size |
140m2 |
100m2 |
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HITACHI home. 
![[Image]Controlled Speed induction Generator System](images/p005_01.jpg)
![[Image]System Configuration - Simple but new -](images/p005_02.jpg)
| Update History |
![[Image]Waveform of inrush current-01](images/p005_04.jpg)
![[Image]Waveform of inrush current-02](images/p005_05.jpg)
