Power conversion apparatus having a boost power factor correction (PFC) function and controlling inrush current and power conversion method thereof

• US 8,837,186 B2
• Filed: 03/06/2012
• Issued: 09/16/2014
• Est. Priority Date: 03/08/2011
• Status: Active Grant

• Current Assignee: LSIS Co. Ltd. (LS Corporation)
• Original Assignee: LSIS Co. Ltd. (LS Corporation)
• Inventors: Lee, Jae Ho
• Primary Examiner(s): Dole, Timothy J
• Assistant Examiner(s): AHMED, YUSEF A
• Application Number:
  US13/413,544
• Publication Number:
  US 20120230075A1
• Time in Patent Office: 924 Days
• Field of Search: 323222-225, 363125-128, 363 84- 89
• US Class Current: 363/128
• CPC Class Codes: H02M 1/0085 Partially controlled bridges
• CPC Class Codes: H02M 1/081 wherein the phase of the control voltage is adjustable with reference to the AC source
• CPC Class Codes: H02M 1/36 Means for starting or stopping converters
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: H02M 7/00 Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
• CPC Class Codes: H02M 7/066 particular circuits having a special characteristic
• CPC Class Codes: H02M 7/1557 with automatic control of the output voltage or current
• 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

An apparatus/method is provided. The power conversion apparatus includes: a rectifying unit including a silicon-controlled rectifier thyristor (SCR) for rectifying single-phase power externally inputted; a power factor correcting unit configured to correct a power factor of the power rectified by the rectifying unit; and a control signal generating unit configured to detect a zero-crossing point based on the single-phase power inputted and generate a pulse single of which a width increases as time elapses based on the detected zero-crossing point. The rectifying unit rectifies the single-phase power by using the pulse signal inputted to a gate terminal of the SCR.

Claims

1. A power conversion apparatus comprising:

a rectifying unit comprising a silicon-controlled rectifier thyristor (SCR) for rectifying externally input single-phase power;

a power factor correcting unit configured to correct a power factor of the rectified power;

a signal detector configured to detect the single-phase power;

a single-phase PLL configured to detect first and second zero-crossing points based on the detected single-phase power and to generate a carrier signal that increases as time elapses based on the detected first and second zero-crossing points; and

a PWM generator configured to compare a reference signal with the generated carrier signal and to generate a pulse signal having a width that increases as time elapses,

wherein the rectifying unit rectifies the single-phase power by using the generated pulse signal input to a gate terminal of the SCR,

wherein the single-phase PLL detects the first zero-crossing point where the single-phase power changes from positive to negative and detects the second zero-crossing point where the single-phase power changes from negative to positive, and

wherein the single-phase PLL generates the carrier signal by;

generating a first carrier signal when the first zero-crossing point is detected and resetting the first carrier signal when the second zero-crossing point is detected; and

generating a second carrier signal when the second zero-crossing point is detected and resetting the second carrier signal when the first zero-crossing point is detected.

2. The power conversion apparatus according to claim 1, wherein the PWM generator generates the pulse signal while the generated carrier signal is greater than the reference signal.

3. The power conversion apparatus according to claim 1, wherein:

the PWM generator compares the first carrier signal with the reference signal to generate a first pulse signal while the first carrier signal is greater than the reference signal; and

the PWM generator compares the second carrier signal with the reference signal to generate a second pulse signal while the second carrier signal is greater than the reference signal.

4. The power conversion apparatus according to claim 3, wherein the SCR comprises:

a first SCR having a gate terminal connected to the first pulse signal output from the PWM generator; and

a second SCR having a gate terminal connected to the second pulse signal output from the PWM generator.

5. The power conversion apparatus according to claim 4, wherein:

the first and second SCRs output currents having intensities that are proportional to the widths of the first and second pulse signals by using the first and second pulse signals input to the gate terminals of the first and second SCR and;

the intensities of the currents increase as time elapses.

6. The power conversion apparatus according to claim 1, further comprising a reference signal generator configured to generate the reference signal, wherein the reference signal decreases as time elapses.

7. A power conversion method of a power conversion apparatus, the power conversion method comprising:

detecting externally input single-phase power;

detecting a plurality of zero-crossing points based on the detected single-phase power;

generating a carrier signal that increases as time elapses based on the detected plurality of zero-crossing points;

generating a pulse signal by comparing the generated carrier signal with a reference signal; and

rectifying the single-phase power by using the generated pulse signal,

wherein detecting the plurality of zero-crossing points comprises;

detecting a first zero-crossing point where the single-phase power changes from positive to negative; and

detecting a second zero-crossing point where the single-phase power changes from negative to positive, and

wherein generating the carrier signal comprises;

generating a first carrier signal when the first zero-crossing point is detected and resetting the first carrier signal when the second zero-crossing point is detected; and

generating a second carrier signal when the second zero-crossing point is detected and resetting the second carrier signal when the first zero-crossing point is detected.

8. The power conversion method according to claim 7, wherein the pulse signal is generated while the generated carrier signal is greater than the reference signal.

9. The power conversion method according to claim 7, wherein generating the pulse signal comprises:

comparing the first carrier signal with the reference signal and generating a first pulse signal while the first carrier signal is greater than the reference signal; and

comparing the second carrier signal with the reference signal and generating a second pulse signal while the second carrier signal is greater than the reference signal.

10. The power conversion method according to claim 9, wherein rectifying the single-phase power:

inputting the first pulse signal to a gate terminal of a first SCR connected to a positive terminal of the single-phase power;

rectifying the single-phase power according to a width of the first pulse signal;

inputting the second pulse signal to a gate terminal of a second SCR connected to a negative terminal of the single-phase power; and

rectifying the single-phase power according to a width of the second pulse signal.

11. The power conversion method according to claim 10, wherein:

rectifying the single-phase power comprises outputting currents having intensities that are proportional to the widths of the first and second pulse signals by using the first and second pulse signals input to the gate terminals of the first and second SCR; and

the intensities of the currents increase as time elapses.

12. The power conversion method according to claim 7, further comprising generating and outputting the reference signal, wherein the reference signal decreases as time elapses.