System For Operating DC Motors And Power Converters

• US 20110068723A1
• Filed: 12/18/2009
• Published: 03/24/2011
• Est. Priority Date: 07/22/2003
• Status: Active Grant

• Current Assignee: Sergio A. Maiocchi
• Original Assignee: Sergio A. Maiocchi
• Inventors: Maiocchi, Sergio A.
• Granted Patent: US 8,587,238 B2
• Time in Patent Office: Days
• US Class Current: 318/400.3
• CPC Class Codes: H02M 1/0012 Control circuits using digital or numerical techniques in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873
• CPC Class Codes: H02M 1/009 having two or more independently controlled outputs for DC-DC converter with intermediate AC H02M3/33561
• CPC Class Codes: H02M 3/1555 for the generation of a regulated current to a load whose impedance is substantially inductive
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/157 with digital control
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 3/3372 of the parallel type
• CPC Class Codes: H02P 2209/07 Trapezoidal waveform
• CPC Class Codes: H02P 6/085 in a bridge configuration
• CPC Class Codes: H02P 7/29 using pulse modulation
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A system is disclosed for driving a DC motor (15) under conditions of a controlled average current. An inductive element may be arranged for connection in series with the DC motor. A switch (14) is preferably coupled to the inductive element for connecting and disconnecting a terminal of the inductive element from the voltage source. A diode may be arranged for connection in parallel with a combination of the inductive element and the DC motor arranged in series, with appropriate polarity so that current circulating through the inductive element circulates through the diode when the switch disconnects the terminal from the voltage source. A capacitor is arranged for connection in parallel with the motor, for limiting a resulting voltage over the motor or for storing charge depending on the embodiment of the invention. A device for measuring a current through the motor is provided, and a device (13) for controlling operation of the switch dependent upon the measured current in the motor is also provided. An airflow apparatus is also disclosed.

Claims

1-46. -46. (canceled)

47. A system for driving a direct-current (DC) motor under conditions of a controlled average current, from a DC voltage source having a larger or smaller value than said motor nominal voltage, said system comprising:

a diode;

a magnetic transformer connected in series with said diode in a circuit arrangement selected from the group consisting of a flyback DC-DC converter and a ringing choke DC-DC converter, said transformer and said diode for connection in series with said motor;

a switch coupled to said magnetic transformer and said diode for connecting and disconnecting a terminal of said magnetic transformer and said diode remote from said motor to said voltage source;

a capacitor arranged for connection in parallel with said motor to limit a resulting voltage over said motor, said capacitor being capable of operating in a buck converter at the power level required to operate said motor and at the frequency of commutation of said switch;

means for measuring a current through said motor; and

means for controlling operation of said switch dependent upon said measured current in said motor.

48. The system according to claim 47, wherein said switch is an electronic switch.

49. The system according to claim 47, wherein a current through an inductance of output windings of said magnetic transformer can be controlled independently from a current through said motor, the balance of electrical charge being accumulated or taken from said capacitor in parallel with said motor.

50. The system according to claim 47, wherein a current through the flyback inductance is modulated as a full wave rectified sinusoid synchronous with an AC main voltage so that the power factor of the system, as a load to the AC main, is improved.

51. The system according to claim 47, wherein said voltage source is a battery.

52. The system according to claim 47, wherein said DC motor is an electronically driven motor, including a brushless motor or a switched reluctance motor.

53. The system according to claim 52, wherein said motor is braked electronically so that a current produced during braking charges said capacitor in parallel with said motor.

54. The system according to claim 47, wherein a frequency of a pulse width modulated waveform, resulting from operation of said switch, is randomized to facilitate EMI compliance.

55. The system according to claim 49, wherein the current through said motor is calculated from the variation of the voltage across said capacitor in parallel with said motor.

56. The system according to claim 47, wherein the voltage over the DC motor is used to estimate the speed of said motor.

57. A system for driving a direct-current (DC) motor under conditions of a controlled average current, from a DC voltage source having a larger or smaller value than said motor nominal voltage, said system comprising:

an electronic synchronous rectification switch;

a magnetic transformer connected in series with said synchronous rectification switch in a circuit arrangement selected from the group consisting of a flyback DC-DC converter and a ringing choke DC-DC converter, said transformer and said synchronous rectification switch for connection in series with said motor;

a switch coupled to said magnetic transformer and said synchronous rectification switch for connecting and disconnecting a terminal of said magnetic transformer and said synchronous rectification switch remote from said motor to said voltage source;

a capacitor arranged for connection in parallel with said motor to limit a resulting voltage over said motor, said capacitor being capable of operating in a buck converter at the power level required to operate said motor and at the frequency of commutation of said switch;

means for measuring a current through said motor; and

means for controlling operation of said switch dependent upon said measured current in said motor.

58. The system according to claim 57, wherein said switch is an electronic switch.

59. The system according to claim 57, wherein a current through an inductance of output windings of said magnetic transformer can be controlled independently from a current through said motor, the balance of electrical charge being accumulated or taken from said capacitor in parallel with said motor.

60. The system according to claim 57, wherein a current through an inductance of output windings of said magnetic transformer is modulated as a full wave rectified sinusoid synchronous with an AC main voltage so that the power factor of the system, as a load to the AC main, is improved.

61. The system according to claim 57, wherein said voltage source is a battery.

62. The system according to claim 57, wherein said DC motor is an electronically driven motor, including a brushless motor or a switched reluctance motor.

63. The system according to claim 62, wherein said motor is braked electronically so that a current produced during braking charges said capacitor in parallel with said motor.

64. The system according to claim 57, wherein a frequency of a pulse width modulated waveform, resulting from operation of said switch, is randomized to facilitate EMI compliance.

65. The system according to claim 60, wherein the current through said motor is calculated from the variation of the voltage across said capacitor in parallel with said motor.

66. The system according to claim 57, wherein the voltage over the DC motor is used to estimate the speed of said motor.