JP2577466Y2 - Power supply - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, and more particularly to a power supply device using a power factor improving circuit composed of an active filter.

[0002]

2. Description of the Related Art As shown in FIG.
The DC power generated by the smoothing circuit of the diode 102, the capacitor C103, and the resistor R103 from the input AC power supply 1 via the auxiliary transformer 105 is supplied to the power save control circuit 13.
1 is supplied.

After that, a transistor Q is connected through a resistor 104 by a control signal from a power save control circuit 131.
102 is controlled and turned on, and the switch SW101 is turned on by the output of this transistor.

Accordingly, when the switch SW101 is turned on, the input AC power supply 1 is supplied to the power factor improvement circuit 102. The power factor improvement circuit 102 improves the power factor of the input AC power supply 1, and the input power having the improved power factor is obtained. The switching circuit 104 converts the AC power supply 1 into a DC power supply.

[0005]

In the conventional power supply device, an auxiliary transformer is required to drive the power save control circuit, so that there is a problem that the cost is increased and the mounting area is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power supply device in which cost increase is minimized and mounting area is minimized.

[0007]

SUMMARY OF THE INVENTION Accordingly, in order to achieve the above-mentioned object, a power supply device according to the present invention is provided with a power factor improvement for improving a power factor of an input AC power supply by an active filter comprising a capacitor and a choke coil. A circuit, a secondary winding provided on the secondary side of the choke coil of the power factor correction circuit, and for generating power, and the power generated from the secondary winding being used as a driving power source for consuming the input AC power. A power saving circuit for controlling power; and a switching circuit for generating a DC power supply from the input AC power supply based on the control of the power saving circuit. And a switching circuit for generating

[0008]

Next, a power supply device according to an embodiment of the present invention will be described.
This will be described with reference to the drawings.

FIG. 1 is a block circuit diagram of a power supply according to an embodiment of the present invention.

A power supply according to an embodiment of the present invention is shown in FIG.
As shown in FIG. 1, a power factor improving circuit 2 for improving the power factor of the input AC power supply 1 by an active filter composed of a capacitor and a choke coil, and a power factor improving circuit 2 provided on the secondary side of the choke coil L1 And a power saving circuit 3 for controlling the power consumption of the input AC power supply 1 using the power generated from the secondary winding 5 as a driving power supply. The switching circuit 4 generates a DC power supply from the input AC power supply 1 based on the control.

The power factor improving circuit 2 includes an input AC power source 1
, The input terminal of which is connected to the diode DB, the capacitor C1, the choke coil L1, the transistor Q1, the diode D1, the capacitor C2 connected to the output terminal of the diode DB, and the IC 21 for controlling the transistor Q1.
And a diode D3 and a capacitor C4 connected to the tertiary winding L3 of the choke coil L1.

The power saving circuit 3 includes a secondary winding 5
A diode D2 and a capacitor C3 for rectifying and smoothing the output voltage, a power save control circuit 31 that operates by supplying the rectified and smoothed output voltage, and a switching circuit that outputs a control signal output from the power save control circuit 31. The light emitting portion PCT of the photocoupler that feeds back to the IC 42 of No. 4 and the light emitting portion P of the photocoupler in response to a control signal from the power save control circuit 31 via the resistor R4.
It comprises a transistor Q2 for controlling the current of CT and a resistor R3.

Further, the switching circuit 4 receives a feedback signal from the switching regulator 41 connected to the output terminal of the power factor correction circuit 2, an IC 42 for controlling the switching regulator 41, and a light emitting unit PCT of a photocoupler. And a light receiving section PCR of a photocoupler for controlling the IC 42 by means of a resistor R2.

Next, the operation of the power supply according to one embodiment of the present invention will be described with reference to FIG.

First, when the switch SW1 is turned on, the input AC power supply 1 is supplied to the power factor correction circuit 2, and the energy stored in the choke coil L1 is generated in the secondary winding 5 when the transistor Q1 is off. The energy generated in the secondary winding 5 is rectified and smoothed by the diode D2 and the capacitor C3, and supplied as a power source for the power save control circuit 31.

The power saving control circuit 31 supplies a resistor R
When a control signal is sent to the base of the transistor Q2 through the transistor 4, the transistor Q2 is turned on to cause the light emitting portion PCT of the photocoupler to emit light, and the light emitting portion P of this photocoupler to emit light.
The light emitting section PCR of the photocoupler is turned on by the light emission of the CT, and the ON / OFF terminal of the IC 42 is turned on ("
L ") to turn on the switching regulator 41.

If the control signal is not sent from the power save control circuit 31, the IC of the switching circuit 4
The ON / OFF terminal 42 is turned off ("H") to stop the switching regulator 41.

Next, a conventional power supply device will be described with reference to the drawings.

FIG. 2 is a block diagram of a conventional power supply device.

As shown in FIG. 2, in the conventional power supply device, a DC power supply generated by a smoothing circuit of a diode 102, a capacitor C103, and a resistor R103 from an input AC power supply 1 via an auxiliary transformer 105 is used as a power save control circuit 131.
Supplied to

Thereafter, the transistor Q is controlled via the resistor 104 by a control signal from the power save control circuit 131.
102 is controlled and turned on, and the switch SW101 is turned on by the output of this transistor.

Accordingly, the switch SW101 is turned on and the input AC power supply 1 is supplied to the power factor improvement circuit 102. The power factor improvement circuit 102 improves the power factor of the input AC power supply 1, and the power factor improved input is obtained. The switching circuit 104 converts the AC power supply 1 into a DC power supply.

[0023]

As described above, according to the power supply device of the present invention, a secondary winding is provided in the choke coil in the power factor correction circuit to generate the power supply for the power save control circuit.
There is an effect that the cost can be reduced by reducing the auxiliary transformer and the mounting area can be reduced.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a power supply device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a conventional power supply device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Input AC power supply 2,102 Power factor improvement circuit 3,103 Power save circuit 4,104 Switching circuit 5 Secondary winding (choke coil) 21 Power factor improvement circuit (IC) 31,131 Power save circuit (Power save control circuit) 41) Switching circuit (switching regulator) 42 Switching circuit (IC) 105 Secondary winding (auxiliary transformer) C1, C2, C4 Power factor improving circuit (capacitor) C3, C103 Power saving circuit (capacitor) D1, D3, DB power Power factor improvement circuit (diode) D2, D102 Power save circuit (diode) L1, L3 Power factor improvement circuit (choke coil) Q1 Power factor improvement circuit (transistor) Q2, Q102 Power save circuit (transistor) PCR switching circuit (photocoupler Light receiving section) PCT Power saving circuit (light emitting part of photo coupler) R1 Power factor improvement circuit (resistance) R2 Switching circuit (resistance) R3, R4, R103, R104 Power saving circuit (resistance) SW1, SW101 Power supply device (switch)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) H02M 3/00-3/44 H02M 7/00-7/40

Claims (1)

(57) [Scope of request for utility model registration] 1. A power factor improving circuit for improving a power factor of an input AC power supply by an active filter including a capacitor and a choke coil, and a power factor improving circuit provided on a secondary side of the choke coil of the power factor improving circuit. A secondary winding that is generated, a power save circuit that controls power consumption of the input AC power supply using the power generated from the secondary winding as a drive power supply, and the input AC power supply based on the control of the power save circuit. And a switching circuit for generating a DC power supply from the power supply.