Electrical generator or motor structure – Non-dynamoelectric – Piezoelectric elements and devices
Patent
1997-10-23
1999-08-24
Dougherty, Thomas M.
Electrical generator or motor structure
Non-dynamoelectric
Piezoelectric elements and devices
H01L 4108, H02M 300
Patent
active
059428350
ABSTRACT:
In a piezoelectric transformer drive circuit, a first autotransformer and a second autotransformer input to their primary terminals from a drive voltage control circuit and impress an ac voltage to each primary electrode of the piezoelectric transformer that is connected to each secondary terminal of the autotransformers; and the piezoelectric transformer supplies voltage generated from the secondary electrodes to a load. A frequency divider circuit alternately drives the first and second switching transistors connected to intermediate terminals of the first and second autotransformers. An output voltage comparison circuit compares the output voltage of the piezoelectric transformer with a prescribed maximum value, and if an overvoltage is detected in the output, the output voltage comparison circuit both outputs a reset signal to frequency control circuit and outputs a control signal to a dimmer circuit that changes duty ratio. The dimmer circuit generates a drive halt signal to drive voltage control circuit, performs duty ratio control, and outputs a control signal to the frequency control circuit such that the frequency of a VCO of the frequency control circuit does not change during drive halts. The frequency control circuit outputs a triangular wave signal to the frequency divider circuit, and the drive voltage control circuit inputs the power source voltage and controls the peak voltage driving the piezoelectric transformer to a fixed level. Furthermore, coils may be used in place of autotransformers.
REFERENCES:
patent: 5675484 (1997-10-01), Shimadaq
patent: 5705877 (1998-01-01), Shimada
patent: 5731652 (1998-03-01), Shimada
patent: 5739622 (1998-04-01), Zaitsu
patent: 5760619 (1998-06-01), Yamaguchi
patent: 5796213 (1998-08-01), Kawasaki
Furuhashi Naoki
Takayoshi Hirokazu
Dougherty Thomas M.
NEC Corporation
LandOfFree
Piezoelectric transformer drive circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Piezoelectric transformer drive circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Piezoelectric transformer drive circuit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-469479