CONTROLLER FOR MULTI-OUTPUT SINGLE MAGNETIC COMPONENT CONVERTER WITH INDEPENDENT REGULATION OF CONSTANT CURRENT AND CONSTANT VOLTAGE OUTPUTS

• US 20190326823A1
• Filed: 03/25/2019
• Published: 10/24/2019
• Est. Priority Date: 12/01/2016
• Status: Active Grant

• Current Assignee: Power Integrations Incorporated
• Original Assignee: Power Integrations Incorporated
• Inventors: Werner, Antonius Jacobus Johannes, Waterson, Matthew David, Jiang, Yuncong Alex, Saint-Pierre, Roland Sylvere
• Granted Patent: US 10,855,191 B2
• Time in Patent Office: Days
• CPC Class Codes: H02M 1/0025 Arrangements for modifying reference values, feedback values or error values in the control loop of a converter
• CPC Class Codes: H02M 1/0043 Converters switched with a phase shift, i.e. interleaved non-isolated DC/DC converters H02M3/1586
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: H05B 45/385 using flyback topology
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• 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 power converter includes a primary winding and multiple output windings to provide multiple independently controlled and regulated outputs with a common return line. The outputs are coupled to independently regulate constant current, constant voltage, or both constant current and constant voltage outputs. A secondary control block is coupled to control a synchronous rectifier switch coupled to the common return line to synchronize switching with a primary side power switch to provide complementary conduction of the primary winding and the multiple output windings. A plurality of controlled power pulse switches is coupled to the multiple output windings. A request of a power pulse from each of the outputs is transferred through the secondary control block to a primary switch control block to turn on the primary side power switch to transfer a power pulse to the multiple output windings and through controlled power pulse switches to the outputs.

Claims

1. A method of converting power comprising:

transferring power pulses from a primary side of a power converter to a secondary side that comprises multiple output windings, wherein transferring power pulses comprises;

switching a primary side power switch in response to a power pulse request; and

providing an independently controlled and regulated output from each of the multiple output windings, wherein providing the independently controlled and regulated output comprises;

generating the power pulse request in response to a power demand of the independently controlled and regulated output;

acknowledging the power pulse request; and

synchronizing switching action between the primary side power switch and a synchronous rectifier.

2. The method of claim 1, wherein the multiple output windings are electrically connected together in series with a common return line.

3. The method of claim 1, wherein the multiple output windings are coupled in a combination of series windings, parallel windings, or both series windings and parallel windings.

4. The method of claim 1, comprising:

referencing a primary switch control block to a primary ground; and

switching the primary side power switch with the primary switch control block.

5. The method of claim 4, wherein switching the primary side power switch with the primary switch control block comprises:

turning off the primary side power switch based on a ramp time modulation (RTM) engine and based on a primary current pulse reaching a peak current limit.

6. The method of claim 5, comprising:

referencing a secondary control block to a secondary ground; and

driving the synchronous rectifier switch.

7. The method of claim 6, comprising:

generating the power pulse request in the secondary control block; and

providing the power pulse request to the primary switch control block through a galvanic isolation link.

8. The method of claim 7, wherein the galvanic isolation link is a magnetic/inductive link.

9. The method of claim 8, comprising:

generating a switching drive pulse in the primary switch control block.

10. The method of claim 1, wherein providing the independently controlled and regulated output further comprises:

receiving a feedback signal; and

regulating the independently controlled and regulated output to have a constant voltage in response to the feedback signal.

11. The method of claim 1, wherein providing the independently controlled and regulated output further comprises:

receiving a feedback signal; and

regulating the independently controlled and regulated output to have a constant current in response to the feedback signal.

12. The method of claim 11, wherein providing the independently controlled and regulated output further comprises:

providing the independently controlled and regulated output to multiple paralleled light emitting diode (LED) strings.

13. The method of claim 11, wherein providing the independently controlled and regulated output further comprises:

controlling a voltage across a constant current output of LED strings.

14. The method of claim 13, wherein controlling the voltage across the constant current output of the LED strings comprises:

equalizing currents in the LED strings.

15. The method of claim 13, wherein controlling the voltage across the constant current output of the LED strings comprises:

controlling a switch using PWM dimming, the switch coupled in series with a current source.

16. The method of claim 15, wherein controlling the switch using PWM dimming comprises:

performing in-phase dimming.

17. The method of claim 15, wherein controlling the switch using PWM dimming comprises:

performing phase-shifted dimming.

18. The method of claim 1, comprising:

adjusting a hold-off time of the primary side power switch in response to load changes.

19. The method of claim 18, comprising:

decreasing the hold-off time of the primary side power switch in response to an increased load.

20. The method of claim 18, comprising:

increasing the hold-off time of the primary side power switch in response to a decreased load.

21. A method of controlling multiple outputs in a power converter comprising:

setting a hold-off signal high and resetting a timer in response to a primary side power switch turning on;

setting the hold-off signal low and setting a target hold-off time value equal to a first value that is a function of a timer when a change in load is detected before the timer reaches the target hold-off time value;

setting the hold-off signal low and setting the target hold-off time value equal to a second value that is the function of the timer when;

no change in load is detected,

the timer has reached the target hold-off time value, and

there is a power pulse request pending; and

setting the hold-off signal low and setting the target hold-off time value equal to a third value that is the function of the timer when;

no change in load is detected,

the timer has reached the target hold-off time value,

there is no power pulse request pending,

a new power pulse request has been issued.