FAN SYSTEM AND BRAKE CONTROL CIRCUIT THEREOF

• US 20110181213A1
• Filed: 01/27/2010
• Published: 07/28/2011
• Est. Priority Date: 01/27/2010
• Status: Active Grant

• Current Assignee: Sunonwealth Electric Machine, Ind. Co., Ltd.
• Original Assignee: Sunonwealth Electric Machine, Ind. Co., Ltd.
• Inventors: Chen, Tung-An, Wu, Kun-Tien, Tsai, Cheng-Nan, HORNG, Alex, Hou, Kuan-Yin
• Granted Patent: US 8,299,735 B2
• Time in Patent Office: Days
• US Class Current: 318/379
• CPC Class Codes: H02P 3/14 by regenerative braking
• CPC Class Codes: H02P 7/29 using pulse modulation

Abstract

A fan system including a motor with a coil, a storage unit, a driver, and a buffer circuit is provided. The coil module has a first connection terminal and a second connection terminal. The storage unit electrically couples with a voltage source, stores electrical energy when the voltage source is available, and releases the stored electrical energy to carry out a brake operation when the voltage source is unavailable. The driver electrically couples with the first and second connection terminals of the coil module to control a direction of an inductor current passing through the coil module. The buffer circuit electrically couples with the coil module. In the brake operation, the buffer circuit operates to form a transient potential between the first and second connection terminals of the coil module and to consume electrical energy of the inductor current, for gradually stopping the motor in a buffering time period.

Claims

1. A fan system, comprising:

a motor with a coil module having a first connection terminal and a second connection terminal;

a storage unit electrically coupling with a voltage source, storing electrical energy when the voltage source is available, and releasing the stored electrical energy to carry out a brake operation when the voltage source is unavailable;

a driver electrically coupling with the first and second connection terminals of the coil module to control a direction of an inductor current passing through the coil module; and

a buffer circuit electrically coupling with the coil module,

wherein, in the brake operation, the buffer circuit operates to form a transient potential between the first and second connection terminals of the coil module and to consume electrical energy of the inductor current, for gradually stopping the motor in a buffering time period.

2. The fan system as defined in claim 1, wherein the driver is a full bridge driver having an upper switch module and a lower switch module, with each of the upper and lower switch modules being constructed by two electronic power switches.

3. The fan system as defined in claim 2 further comprising a control unit electrically coupling with the driver.

4. The fan system as defined in claim 3 further comprising a brake circuit electrically coupling with the control unit, with the brake circuit having two electronic power switches, with each of the two electronic power switches of the brake circuit having an input terminal, and with the two input terminals respectively coupling with the electronic power switches of the lower switch module through output terminals thereof.

5. The fan system as defined in claim 1, wherein the buffer circuit comprises a buffer element and an actuating member in series connection with the buffer element, with a combination circuit of the buffer element and the actuating member coupling with the coil module in parallel connection.

6. The fan system as defined in claim 5, wherein the actuating member electrically couples with the storage unit.

7. The fan system as defined in claim 5, wherein the buffer element and the actuating member of the buffer circuit and the coil module jointly define a buffering close loop.

8. The fan system as defined in claim 7, wherein the buffer circuit further comprises a power state sensing switch electrically coupling with the actuating member to send out a result signal for control over the actuating member.

9. The fan system as defined in claim 8, wherein the actuating member and the power state sensing switch are transistors.

10. The fan system as defined in claim 5, wherein the buffer element is a resistor, and resistance of the resistor and inductance of the coil module jointly determine a buffering time period to decide a time period of the brake operation.

11. The fan system as defined in claim 5, wherein the buffer element is a resistor with small resistance not larger than 1 ohm.

12. The fan system as defined in claim 7, wherein the buffer circuit further comprises a diode serially connecting within the buffering close loop.

13. The fan system as defined in claim 4, wherein the storage unit electrically couples with the driver and the brake circuit.

14. The fan system as defined in claim 3, wherein the buffer circuit comprises a buffer element and an actuating member in series connection with the buffer element, with a combination circuit of the buffer element and the actuating member coupling between the first connection terminal of the coil module and the storage unit.

15. The fan system as defined in claim 14, wherein the coil module, the buffer element, the actuating member, and one of the two electronic power switches of the upper switch module jointly define a buffering close loop.

16. The fan system as defined in claim 15, wherein said electronic power switch in the buffering close loop couples with the second connection terminal of the coil module.

17. The fan system as defined in claim 14, wherein the actuating member of the buffer circuit is a P-channel transistor.

18. The fan system as defined in claim 2 further comprising a control unit electrically coupling with the driver and the buffer circuit.

19. The fan system as defined in claim 18, wherein the buffer circuit comprises a buffer element, an actuating member, a first power state sensing switch, and a second power state sensing switch, with the buffer element serially connecting with the actuating member, with a combination circuit of the buffer element and the actuating member coupling between the first connection terminal of the coil module and the ground, with the first power state sensing switch electrically coupling with the actuating member, and with the second power state sensing switch electrically coupling with one of the two electronic power switches of the lower switch module.

20. The fan system as defined in claim 18, wherein the storage unit comprises a first storage element electrically coupling with the driver.

21. The fan system as defined in claim 19, wherein the storage unit comprises a second storage element electrically coupling with the actuating member, the first power state sensing switch, and the second power state sensing switch of the buffer circuit.

22. The fan system as defined in claim 19, wherein the coil module, the buffer element, the actuating member, and said electronic power switch of the lower switch module jointly define a buffering close loop.

23. The fan system as defined in claim 22, wherein said electronic power switch in the buffering close loop electrically coupling with the second connection terminal of the coil module.

24. The fan system as defined in claim 19, wherein the actuating member of the buffer circuit is an N-channel transistor.

25. A brake control circuit of a fan system, comprising:

a buffer circuit actuated when a voltage source of a fan system is turned off, with the actuated buffer circuit forming a transient potential between a first connection terminal and a second connection terminal of a coil module of the fan system for consuming a inductor current of the coil module, so as to gradually stop the fan system in a buffering time period.

26. The brake control circuit of a fan system as defined in claim 25 further comprising a driver being a full bridge driver having an upper switch module and a lower switch module, with each of the upper and lower switch modules being constructed by two electronic power switches.

27. The brake control circuit of a fan system as defined in claim 26 further comprising a control unit electrically coupling with the driver.

28. The brake control circuit of a fan system as defined in claim 27 further comprising a brake circuit electrically coupling with the control unit, with the brake circuit having two electronic power switches, with each of the two electronic power switches of the brake circuit having an input terminal, and with the two input terminals respectively coupling with the electronic power switches of the lower switch module through output terminals thereof.

29. The brake control circuit of a fan system as defined in claim 25, wherein the buffer circuit comprises a buffer element and an actuating member in series connection with the buffer element, with a combination circuit of the buffer element and the actuating member coupling with the coil module in parallel connection.

30. The brake control circuit of a fan system as defined in claim 29, wherein the actuating member electrically couples with a storage unit.

31. The brake control circuit of a fan system as defined in claim 29, wherein the buffer element and the actuating member of the buffer circuit and the coil module jointly define a buffering close loop.

32. The brake control circuit of a fan system as defined in claim 30, wherein the buffer circuit further comprises a power state sensing switch electrically coupling with the actuating member to send out a result signal for control over the actuating member.

33. The brake control circuit of a fan system as defined in claim 32, wherein the actuating member and the power state sensing switch are transistors.

34. The brake control circuit of a fan system as defined in claim 29, wherein the buffer element is a resistor, and resistance of the resistor and inductance of the coil module jointly determine a buffering time period to decide a time period of the brake operation.

35. The brake control circuit of a fan system as defined in claim 29, wherein the buffer element is a resistor with small resistance not larger than 1 ohm.

36. The brake control circuit of a fan system as defined in claim 31, wherein the buffer circuit further comprises a diode serially connecting within the buffering close loop.

37. The brake control circuit of a fan system as defined in claim 28, wherein the buffer circuit comprises a buffer element and an actuating member in series connection with the buffer element, with a combination circuit of the buffer element and the actuating member coupling between the first connection terminal of the coil module and the storage unit.

38. The brake control circuit of a fan system as defined in claim 37, wherein the coil module, the buffer element, the actuating member, and one of the two electronic power switches of the upper switch module jointly define a buffering close loop.

39. The brake control circuit of a fan system as defined in claim 38, wherein said electronic power switch in the buffering close loop couples with the second connection terminal of the coil module.

40. The brake control circuit of a fan system as defined in claim 37, wherein the actuating member of the buffer circuit is a P-channel transistor.

41. The brake control circuit of a fan system as defined in claim 26 further comprising a control unit electrically coupling with the driver and the buffer circuit.

42. The brake control circuit of a fan system as defined in claim 41, wherein the buffer circuit comprises a buffer element, an actuating member, a first power state sensing switch, and a second power state sensing switch, with the buffer element serially connecting with the actuating member, with a combination circuit of the buffer element and the actuating member coupling between the first connection terminal of the coil module and the ground, with the first power state sensing switch electrically coupling with the actuating member, and with the second power state sensing switch electrically coupling with one of the two electronic power switches of the lower switch module.

43. The brake control circuit of a fan system as defined in claim 41 further comprising a first storage element electrically coupling with the driver.

44. The brake control circuit of a fan system as defined in claim 42 further comprising a second storage element electrically coupling with the actuating member, the first power state sensing switch, and the second power state sensing switch of the buffer circuit.

45. The brake control circuit of a fan system as defined in claim 42, wherein the coil module, the buffer element, the actuating member, and said electronic power switch of the lower switch module jointly define a buffering close loop.

46. The brake control circuit of a fan system as defined in claim 45, wherein said electronic power switch in the buffering close loop electrically coupling with the second connection terminal of the coil module.

47. The brake control circuit of a fan system as defined in claim 42, wherein the actuating member of the buffer circuit is an N-channel transistor.