Systems and methods for output current regulation in power conversion systems

• US 10,340,795 B2
• Filed: 03/21/2018
• Issued: 07/02/2019
• Est. Priority Date: 05/15/2015
• Status: Active Grant

• Current Assignee: On-Bright Electronics (Shanghai) Co., Ltd. (Orthosie Investment Holdings Ltd.)
• Original Assignee: On-Bright Electronics (Shanghai) Co., Ltd. (Orthosie Investment Holdings Ltd.)
• Inventors: Fang, Qian, Lan, Cong, Fang, Lieyi
• Primary Examiner(s): Gblende, Jeffrey A
• Assistant Examiner(s): Quddus, Nusrat
• Application Number:
  US15/927,790
• Publication Number:
  US 20180287492A1
• Time in Patent Office: 468 Days
• Field of Search: 363 2112- 2118, 363 52, 363 53, 363125-127
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• 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 3/33515 with digital control
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
• 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

Systems and methods are provided for regulating a power converter. An example system controller includes: a driver configured to output a drive signal to a switch to affect a current flowing through an inductive winding of a power converter, the drive signal being associated with a switching period including an on-time period and an off-time period. The switch is closed in response to the drive signal during the on-time period. The switch is opened in response to the drive signal during the off-time period. A duty cycle is equal to a duration of the on-time period divided by a duration of the switching period. One minus the duty cycle is equal to a parameter. The system controller is configured to keep a multiplication product of the duty cycle, the parameter and the duration of the on-time period approximately constant.

Claims

1. A system controller for regulating a power converter, the system controller comprising:

a driver configured to output a drive signal to a switch to affect a current flowing through an inductive winding of a power converter, the drive signal being associated with a switching period including an on-time period and an off-time period;

wherein;

the switch is closed in response to the drive signal during the on-time period;

the switch is opened in response to the drive signal during the off-time period;

a duty cycle is equal to a duration of the on-time period divided by a duration of the switching period; and

one minus the duty cycle is equal to a parameter;

wherein the system controller is configured to keep a multiplication product of the duty cycle, the parameter and the duration of the on-time period approximately constant.

2. The system controller of claim 1, further comprising a controller terminal configured to receive a first signal related to an input signal of the power converter.

4. The system controller of claim 1 wherein an error range of the multiplication product being approximately constant is equal to ±

5%.

5. The system controller of claim 1 wherein an error range of the multiplication product being approximately constant is equal to ±

10%.

6. The system controller of claim 1 wherein an error range of the multiplication product being approximately constant is equal to ±

15%.

7. The system controller of claim 1 wherein an error range of the multiplication product being approximately constant is equal to ±

20%.

3. A method for regulating a power conversion system, the method comprising:

generating a drive signal associated with a switching period including an on-time period and an off-time period; and

outputting the drive signal to a switch to affect a current flowing through an inductive component;

wherein the outputting the drive signal to the switch to affect the current includes;

outputting the drive signal to close the switch during the on-time period; and

outputting the drive signal to open the switch during the off-time period;

wherein;

a duty cycle is equal to a duration of the on-time period divided by a duration of the switching period; and

one minus the duty cycle is equal to a parameter;

wherein the generating the drive signal associated with the switching period includes keeping a multiplication product of the duty cycle, the parameter and the duration of the on-time period approximately constant.

8. The method of claim 3 wherein an error range of the multiplication product being approximately constant is equal to ±

5%.

9. The method of claim 3 wherein an error range of the multiplication product being approximately constant is equal to ±

10%.

10. The method of claim 3 wherein an error range of the multiplication product being approximately constant is equal to ±

15%.

11. The method of claim 3 wherein an error range of the multiplication product being approximately constant is equal to ±

20%.