Systems and methods for high precision and/or low loss regulation of output currents of power conversion systems

• US 10,211,740 B2
• Filed: 02/09/2017
• Issued: 02/19/2019
• Est. Priority Date: 07/19/2013
• 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: Zhu, Liqiang, Yang, Jiqing, Chen, Yaozhang, Li, Zhuoyan, Luo, Qiang, Fang, Lieyi
• Primary Examiner(s): Tran, Nguyen
• Application Number:
  US15/429,011
• Publication Number:
  US 20170214328A1
• Time in Patent Office: 740 Days
• Field of Search: 363 20, 363 2104, 363 2105, 363 2107, 363 2108, 363 2109, 363 211, 363 2111, 363 2112, 363 3, 363 2115- 2118
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 1/0022 the disturbance parameters being input voltage fluctuations
• 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 1/36 Means for starting or stopping converters
• 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: H05B 45/325 Pulse-width modulation [PWM]
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 45/382 with galvanic isolation between input and output

Abstract

Systems and methods are provided for signal processing. An example error amplifier for processing a reference signal and an input signal associated with a current of a power conversion system includes a first operational amplifier, a second operational amplifier, a first transistor, a second transistor, a current mirror component, a switch, a first resistor and a second resistor. The first operational amplifier includes a first input terminal, a second input terminal and a first output terminal, the first input terminal being configured to receive a reference signal. The first transistor includes a first transistor terminal, a second transistor terminal and a third transistor terminal, the first transistor terminal being configured to receive a first amplified signal from the first output terminal, the third transistor terminal being coupled to the second input terminal.

Claims

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

a first controller terminal configured to receive a first voltage associated with a first current, the first current being related to an input voltage of a power conversion system;

a compensation component coupled to the first controller terminal and configured to, if the first voltage satisfies one or more first conditions, generate a compensation current based on at least information associated with the first current;

a second controller terminal coupled to the compensation component and configured to provide a compensation voltage based on at least information associated with the compensation current, the compensation voltage being equal in magnitude to the compensation current multiplied by a compensation resistance, the compensation resistance being associated with a compensation resistor;

a current sensing component configured to receive a second voltage and generate a first output signal, the second voltage being equal to a sum of a third voltage and the compensation voltage in magnitude, the third voltage being proportional to a second current flowing through a primary winding of the power conversion system; and

an error amplifier configured to receive the first output signal and a first reference signal, generate an amplified signal based on at least information associated with the first output signal and the first reference signal, and output the amplified signal to affect a switch associated with the second current.

2. The system controller of claim 1 wherein the one or more first conditions are satisfied if the first voltage is approximately equal to a ground voltage.

3. The system controller of claim 1 wherein the first controller terminal is coupled to a first resistor terminal of a first resistor, the first resistor further including a second resistor terminal biased to a ground voltage.

4. The system controller of claim 3 wherein the first controller terminal is coupled to a third resistor terminal of a second resistor, the second resistor further including a fourth resistor terminal coupled to an auxiliary winding of the power conversion system.

5. The system controller of claim 1 wherein the second controller terminal is coupled to the compensation resistor.

6. The system controller of claim 1 wherein the error amplifier includes:

a first operational amplifier including a first input terminal, a second input terminal and a first output terminal, the first input terminal being configured to receive the first reference signal;

a first transistor including a first transistor terminal, a second transistor terminal and a third transistor terminal, the first transistor terminal being coupled to the first output terminal, the third transistor terminal being coupled to the second input terminal;

a second operational amplifier including a third input terminal, a fourth input terminal and a second output terminal, the third input terminal being configured to receive the first output signal;

a second transistor including a fourth transistor terminal, a fifth transistor terminal and a sixth transistor terminal, the fourth transistor terminal being coupled to the second output terminal, the sixth transistor terminal being coupled to the fourth input terminal;

a current mirror component including a first component terminal and a second component terminal, the first component terminal being coupled to the second transistor terminal;

a switch including a first switch terminal and a second switch terminal, the first switch terminal being coupled to the second component terminal, the second switch terminal being coupled to the fifth transistor terminal;

a first resistor including a first resistor terminal and a second resistor terminal, the first resistor being associated with a first resistance, the first resistor terminal being coupled to the second input terminal; and

a second resistor including a third resistor terminal and a fourth resistor terminal, the second resistor being associated with a second resistance, the third resistor terminal being coupled to the fourth input terminal;

wherein;

the first output terminal is configured to output a second output signal to the first transistor terminal;

the second output terminal is configured to output a third output signal to the fourth transistor terminal; and

the first resistance is larger than the second resistance in magnitude.

7. The system controller of claim 1 wherein:

the first controller terminal is configured to receive a feedback signal associated with an output voltage of the power conversion system;

a load-compensation component is configured to sample the feedback signal during a demagnetization process of the power conversion system and generate a third current based on at least information associated with the sampled feedback signal;

the error amplifier includes a first input terminal, a second input terminal, and an output terminal coupled to the load-compensation component, the first input terminal being configured to receive a fourth voltage, the second input terminal being configured to receive a second reference signal, the output terminal being configured to output an output current;

the output current is equal to a difference between an amplified current and the third current in magnitude; and

the amplified current is related to a difference between the fourth voltage and the second reference signal in magnitude.

8. The system controller of claim 1 wherein the compensation component includes:

an operational amplifier including a first input terminal, a second input terminal, and an output terminal;

a first transistor including a first transistor terminal, a second transistor terminal, and a third transistor terminal; and

a current mirror component including a first component terminal and a second component terminal;

wherein;

the first input terminal is biased to a ground voltage;

the second input terminal is coupled to the first controller terminal and the third transistor terminal;

the output terminal is coupled to the first transistor terminal;

the second transistor terminal is coupled to the second component terminal; and

the first component terminal is coupled to the second controller terminal.

9. A system controller for regulating a power conversion system, the system controller comprising:

a first controller terminal configured to receive a feedback signal associated with an output voltage of a power conversion system;

a compensation component coupled to the first controller terminal and configured to sample the feedback signal during a demagnetization process of the power conversion system and generate a compensation current based on at least information associated with the sampled feedback signal;

a second controller terminal coupled to the compensation component and configured to provide a compensation voltage based on at least information associated with the compensation current, the compensation voltage being equal in magnitude to the compensation current multiplied by a compensation resistance, the compensation resistance being associated with a compensation resistor;

a current sensing component configured to receive an input voltage and generate a first output signal, the input voltage being equal to a sum of a first voltage and the compensation voltage in magnitude, the first voltage being proportional to a first current flowing through a primary winding of the power conversion system; and

an error amplifier configured to receive the first output signal and a reference signal, generate an amplified signal based on at least information associated with the first output signal and the reference signal, and output the amplified signal to affect a switch associated with the first current.

10. The system controller of claim 9 wherein the first controller terminal is coupled to a first resistor terminal of a first resistor, the first resistor further including a second resistor terminal biased to a ground voltage.

11. The system controller of claim 10 wherein the first controller terminal is coupled to a third resistor terminal of a second resistor, the second resistor further including a fourth resistor terminal coupled to an auxiliary winding of the power conversion system.

12. The system controller of claim 9 wherein the second controller terminal is coupled to the compensation resistor.

13. The system controller of claim 9 wherein the error amplifier includes:

a first operational amplifier including a first input terminal, a second input terminal and a first output terminal, the first input terminal being configured to receive the reference signal;

a first transistor including a first transistor terminal, a second transistor terminal and a third transistor terminal, the first transistor terminal being coupled to the first output terminal, the third transistor terminal being coupled to the second input terminal;

a second operational amplifier including a third input terminal, a fourth input terminal and a second output terminal, the third input terminal being configured to receive the first output signal;

a second transistor including a fourth transistor terminal, a fifth transistor terminal and a sixth transistor terminal, the fourth transistor terminal being coupled to the second output terminal, the sixth transistor terminal being coupled to the fourth input terminal;

a current mirror component including a first component terminal and a second component terminal, the first component terminal being coupled to the second transistor terminal;

a switch including a first switch terminal and a second switch terminal, the first switch terminal being coupled to the second component terminal, the second switch terminal being coupled to the fifth transistor terminal;

a first resistor including a first resistor terminal and a second resistor terminal, the first resistor being associated with a first resistance, the first resistor terminal being coupled to the second input terminal; and

a second resistor including a third resistor terminal and a fourth resistor terminal, the second resistor being associated with a second resistance, the third resistor terminal being coupled to the fourth input terminal;

wherein;

the first output terminal is configured to output a second output signal to the first transistor terminal;

the second output terminal is configured to output a third output signal to the fourth transistor terminal; and

the first resistance is larger than the second resistance in magnitude.

14. The system controller of claim 9 wherein the compensation component includes:

an operational amplifier including a first input terminal, a second input terminal, and an output terminal;

a first transistor including a first transistor terminal, a second transistor terminal, and a third transistor terminal;

a sample-and-hold component including a first component terminal and a second component terminal; and

a current mirror component including a third component terminal and a fourth component terminal;

wherein;

the first component terminal is coupled to the first controller terminal;

the second component terminal is coupled to the first input terminal;

the second input terminal is coupled to the third transistor terminal;

the output terminal is coupled to the first transistor terminal;

the second transistor terminal is coupled to the fourth component terminal; and

the third component terminal is coupled to the second controller terminal.

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

receiving a first voltage associated with a first current, the first current being related to an input voltage of a power conversion system;

generating, if the first voltage satisfies one or more first conditions, a compensation current based on at least information associated with the first current;

providing a compensation voltage based on at least information associated with the compensation current, the compensation voltage being equal in magnitude to the compensation current multiplied by a compensation resistance, the compensation resistance being associated with a compensation resistor;

receiving the input voltage, the input voltage being equal to a sum of a second voltage and the compensation voltage in magnitude, the second voltage being proportional to a second current flowing through a primary winding of the power conversion system;

generating an output signal based on at least information associated with the input voltage;

receiving the output signal and a reference signal;

generating an amplified signal based on at least information associated with the output signal and the reference signal; and

outputting the amplified signal in order to affect a switch associated with the second current.

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

receiving a feedback signal associated with an output voltage of a power conversion system;

sampling the feedback signal during a demagnetization process of the power conversion system;

generating a compensation current based on at least information associated with the sampled feedback signal;

providing a compensation voltage based on at least information associated with the compensation current, the compensation voltage being equal in magnitude to the compensation current multiplied by a compensation resistance, the compensation resistance being associated with a compensation resistor;

receiving an input voltage, the input voltage being equal to a sum of a first voltage and the compensation voltage in magnitude, the first voltage being proportional to a first current flowing through a primary winding of the power conversion system;

generating an output signal;

receiving the output signal and a reference signal;

generating an amplified signal based on at least information associated with the output signal and the reference signal; and

outputting the amplified signal to affect a switch associated with the first current.