Power protection apparatus and method

Patent metadata

Field	Value
Publication number	US-9755422-B2
Application number	US-201314022835-A
Country	US
Kind code	B2
Filing date	Sep 10, 2013
Priority date	Feb 5, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A power-protection apparatus is provided. The apparatus includes an over-voltage protection unit for generating an over-voltage detection signal when the power supply of the load is over the upper limit of a predetermined voltage range; an under-voltage protection unit for generating an under-voltage detection signal when the power supply of the load is under the lower limit of the predetermined voltage range; a working-state detection unit for receiving a control signal and generating a working-state detection signal when the level time-change rate of the control signal is over a time-change rate threshold; and a power-control unit coupled to the over-voltage protection unit, the working-state detection unit and the under-voltage protection unit for controlling the on and off of the power supply according to the over-voltage detection signal, the under-voltage detection signal or the working-state detection signal.

First claim

What is claimed is:

1. A power-protection apparatus for protecting a load, comprising:
an over-voltage protection unit to generate an over-voltage detection signal when a power supply of the load is over an upper limit of a predetermined voltage range;
an under-voltage protection unit to generate an under-voltage detection signal when the power supply of the load is under a lower limit of the predetermined voltage range;
a working-state detection unit to receive a rotation-speed control signal and generating a working-state detection signal when a pulse width of the rotation-speed control signal is over a predetermined pulse width; and
a power-control unit coupled to the over-voltage protection unit, the working-state detection unit and the under-voltage protection unit for controlling the on and off of the power supply according to the over-voltage detection signal, the under-voltage detection signal or the working-state detection signal.

2. The power-protection apparatus as claimed in claim 1 , wherein the power-control unit turns off the power supply when receiving the over-voltage detection signal, the under-voltage detection signal, or the working-state detection signal.

3. The power-protection apparatus as claimed in claim 1 , wherein the working-state detection unit is coupled between the over-voltage protection unit and the power-control unit, and shuts down when receiving the over-voltage detection signal.

4. The power-protection apparatus as claimed in claim 1 , wherein the under-voltage protection unit is coupled between the over-voltage protection unit and the power-control unit, and shuts down when receiving the over-voltage detection signal.

5. The power-protection apparatus as claimed in claim 1 , wherein the over-voltage protection unit comprises:
a voltage subtractor for subtracting a part of the power supply which is over the upper limit of the predetermined voltage range for producing the over-voltage detection signal.

6. The power-protection apparatus as claimed in claim 5 , wherein the over-voltage protection unit further comprises a regulator circuit for regulating signals provided by the voltage subtractor so as to make the signals exhibit a waveform to be accepted by the power-control unit and avoid malfunctions.

7. The power-protection apparatus as claimed in claim 1 , wherein the under-voltage protection unit comprises a voltage subtractor for subtracting a part of the power supply that is under the lower limit of the predetermined voltage range to directly produce the under-voltage detection signal.

8. The power-protection apparatus as claimed in claim 7 , wherein the under-voltage protection unit further comprises a regulator circuit for regulating the signals provided by the voltage subtractor so as to make the signals exhibit a waveform to be accepted by the power-control unit and avoid malfunctions.

9. The power-protection apparatus as claimed in claim 1 , wherein the working-state detection unit comprises a signal converter.

10. The power-protection apparatus as claimed in claim 9 , wherein the working-state detection unit further comprises a regulator circuit for regulating a signal provided by the signal converter so as to make the signal exhibit a waveform to be accepted by the power-control unit and avoid malfunctions.

11. A power-protection method for protecting a load, comprising steps of:
generating an over-voltage detection signal by an over-voltage protection unit when a power supply of the load is over an upper limit of a predetermined voltage range;
generating an under-voltage detection signal by an under-voltage protection unit when the power supply of the load is under a lower limit of the predetermined voltage range;
receiving a rotation-speed control signal and generating a working-state detection signal by a working-state detection unit when a pulse width of the rotation-speed control signal is over a predetermined pulse width;
wherein the working-state detection unit is coupled to the over-voltage protection unit and the under-voltage protection unit; and
turning off the power supply when receiving the over-voltage detection signal, the under-voltage detection signal, or the working-state detection signal.

Assignees

• Delta Electronics Inc

Inventors

• Lin Che-Hung
• Huang Yueh-Lung
• Chen Yen-Hung

Classifications

• H02H7/09 Primary

  against over-voltage; against reduction of voltage; against phase interruption · CPC title

• H02H3/207 Primary

  also responsive to under-voltage (window comparators for indication G01R19/165) · CPC title