KR100637286B1 - power supply apparatus for inverter - Google Patents

Abstract

The present invention relates to an inverter power supply device, comprising: a power supply device for converting commercial AC; A power supply input terminal for supplying a commercial AC power source, an inductor having an AC energy storage path supplied from the power supply input terminal, transistors Q1 and Q2 connected in series with the inductor, and transistors Q1 and Q2. Transistors Q3 and Q4 connected in parallel and converting AC into direct current, and connected in parallel between the transistors Q1 and Q2 and Q3 and Q4 are connected in parallel to the switching operation of transistors Q1 to Q4. A battery charging a voltage, a smoothing capacitor connected in parallel to the battery to reduce the ripple voltage of the direct current, and transistors Q5 and Q6 connected in parallel to the transistors Q3 and Q4 and converting the direct current into alternating current; And a transformer having one side connected to the transistors Q5 and Q6 and the other side connected to the inductor, and a gate terminal of the transistors Q1 to Q6 according to a change in power voltage and power current of the power input terminal. Is constituted by a control unit which outputs a signal referred to, and the power factor correction mode, the inverter mode is operated in a direction to cancel each other to enhance the reduction in conduction loss and switching loss caused by the current sikimeuroseo power efficiency a power factor compensation.

Inverter, power, power factor correction, high efficiency

Description

Power supply apparatus for inverter

1 is a view showing a conventional power supply,

2 is a view showing a rectifier circuit method using a conventional IGBT;

3 is a block diagram of an inverter power supply apparatus according to an embodiment of the present invention;

4 is a detailed circuit diagram of an inverter power supply apparatus according to an embodiment of the present invention;

5 is a current flow diagram of the inverter power supply apparatus according to the present invention,

6 is a control algorithm of the voltage sensing unit applied to the present invention.

7 is an inverter control block diagram applied to the present invention.

Explanation of symbols on the main parts of the drawings

10: power input terminal 20: voltage detection unit

30: current sensing unit 40: control unit

50: power factor correction unit 60: inverter

70: load

The present invention relates to a power supply device used in an inverter, and more particularly, to an inverter power supply device which operates in a direction in which the power factor correction mode and the inverter mode cancel each other to reduce conduction loss and switching loss caused by current.

In general, as shown in FIG. 1, a power supply device has a power factor correction (PFC) that compensates for a power factor of an output voltage between the rectifier circuit 100 and an electrical load 400. A circuit 200 and a pulse width modulation (PWM) circuit 300.

The rectifier circuit 100 is composed of a bridge diode, and converts an AC power supply voltage of 90 to 260V into a DC voltage of a pulse wave waveform.

The PFC circuit 200 includes a booster transformer T for boosting the output voltage of the rectifier circuit 100 according to the PFC controller 220, the switching transistor TR, and the switching transistor TR. And a diode (D) for rectifying the induced voltage of the primary winding of the booster transformer (T), a smoothing capacitor (C), and a voltage divider (R1, R2) for regulating the output voltage of the PFC circuit (200).

Therefore, the PFC circuit 200 is operated by the DC voltage provided from the rectifier circuit 100 of the power supply device, and at this time, the DC output voltage is changed according to the on / off operation of the switching transistor TR of the PFC circuit 200. It is about 400V. The output voltage is supplied to the power supply voltage of the PWM control circuit 300 to operate the main power supply circuit (not shown) normally.

However, such a conventional power supply device has a power factor lowered due to switching loss caused by switching on / off of the switching transistor TR, and when the power factor is bad, the switching transistor TR, the diode D, and the capacitor ( There was a problem that the power efficiency is lowered by generating a significant power consumption of reactive power components to the components such as C).

In order to solve such a problem, conventionally, as shown in FIG. 2, the power factor is corrected by using the rectification circuit method using the IGBTs Q11 to Q14. This method obtains a power factor close to 1 (0.99). However, due to complex control circuits and high switching frequency, it may cause a problem in reliability, and as a noise source itself, there is a problem in that it is difficult to design a noise filter and a material cost increase to solve this problem.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to operate in a direction in which the power factor correction mode and the inverter mode cancel each other to reduce the conduction loss and switching loss caused by current, thereby reducing power efficiency. To provide an inverter power supply that increases the power factor and compensates for the power factor.

In order to achieve the above object, an inverter power supply device according to the present invention comprises: a power supply device for converting commercial AC; A power input terminal for supplying a commercial AC power source, a transformer having an energy accumulation path of AC supplied from the power input terminal, transistors Q1 and Q2 connected in series to the transformer, and the transistors Q1 and Q2. Transistors Q3 and Q4 connected in parallel and converting AC into direct current, and connected in parallel between the transistors Q1 and Q2 and Q3 and Q4 are connected in parallel to the switching operation of transistors Q1 to Q4. A battery charging a voltage, a smoothing capacitor connected in parallel to the battery to reduce the ripple voltage of the direct current, and transistors Q5 and Q6 connected in parallel to the transistors Q3 and Q4 and converting the direct current into alternating current; And a transformer having one side connected to the transistors Q5 and Q6 and the other side connected to the transformer, and a gate terminal of the transistors Q1 to Q6 according to a change in power voltage and power current of the power input terminal. Characterized in that configured by a control unit which outputs a signal referred to.

A triac is connected directly between the transformer and the transformer to an output terminal. A smoothing capacitor for filtering noise components is connected in parallel. The transistors Q3 and Q4 are connected to each other. The power factor compensation charging mode and the inverter mode are operated in a direction to cancel each other according to the switching signal of the controller.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of an inverter power supply apparatus according to an embodiment of the present invention, Figure 4 is a detailed circuit diagram of the inverter power supply apparatus according to an embodiment of the present invention.

3 and 4, the inverter power supply apparatus according to the present invention, the power input terminal 10, the voltage sensing unit 20, the current sensing unit 30, the control unit 40, the power factor correction unit 50 ) And an inverter 60.

The power input terminal 10 is a main power terminal for supplying AC input power of 90 ~ 260V, the voltage sensing unit 20 detects the power supply voltage of the AC input power supplied from the power input terminal 10, the current The detector 30 detects a power current of the AC input power.

The control unit 40 outputs a switching signal of the pulse width modulation (PWM) so that the waveform of the AC power current becomes a sine wave in synchronization with the zero potential point of the AC input power input from the power input terminal 10. The microcomputer determines the operating frequency of the load 70 according to the system control program stored therein and outputs the inverter driving signal. The basic control value (turn-on time) of the switching element corresponding to the operating frequency of the load 70 is rom. It is stored on the table.

The power factor correction unit 50 is a charging circuit that converts AC input power supplied from the power input terminal 10 into DC power, and smoothes filtering noise components included in the AC input power input from the power input terminal 10. The capacitor C2 and the smoothing capacitor C2 are connected in parallel to accumulate current when a positive voltage is applied, and continue to flow in the same direction by the accumulated amount when a negative voltage is applied. A voltage booster transformer T1 having an energy accumulation path by delaying the phase of the current, and a high frequency switching signal PWM of 15 KHz from the controller 40 so that current flows in the transformer T1 connected to the transformer T1. Transistors Q1 and Q2 switched according to switching), transistors Q3 and Q4 connected in parallel to the transistors Q1 and Q2 and switched according to a 60 Hz low frequency switching signal from the controller 40, and The protective diodes D1 to D4 connected in parallel to the jistors Q1 to Q4 and the transistors Q1 and Q2 and the transistors Q3 and Q4 are connected in parallel to each other according to the switching operation of the transistors Q1 to Q4. A rechargeable battery BT for charging a DC voltage and a smoothing capacitor C1 connected in parallel with the battery BT to reduce the ripple voltage of DC.

The inverter 60 converts the DC power converted by the power factor correction unit 50 into an AC power source, and is connected in parallel to the transistors Q3 and Q4 of the power factor correction unit 50 and from the control unit 40. Transistors Q5 and Q6 switched to implement a full bridge PWM converter by receiving a PWM signal in conjunction with the transistors Q3 and Q4, and protective diodes D5 and D6 connected in parallel to the transistors Q5 and Q6, respectively. ), One side is connected to the transistors Q5 and Q6, the other is connected to the transformer T1, and the other is connected to the smoothing capacitor C2, and the other side is connected to the smoothing capacitor C3. A triac for bypass that is connected to the switching signal of the controller 40 and bypasses the input power directly to the output power, and is connected in parallel to the secondary side of the transformer T2 to filter out noise components. Consisting of a smoothing capacitor (C3) All.

Hereinafter, the effect of the inverter power supply device configured as described above will be described.

When AC input power supplied from the power input terminal 10 is applied to the primary side of the voltage booster transformer T1 via the smoothing capacitor C2 of the power factor correction unit 50, the AC input supplied from the power input terminal 10 is supplied. The power supply voltage of the power supply is sensed by the voltage sensing unit 20 according to the control algorithm shown in FIG. 6, and the power current of the AC input power is sensed by the current sensing unit 30.

The phase of the input current flowing through the transformer T1 by receiving the power supply voltage sensed by the voltage sensing unit 20 and the power current sensed by the current sensing unit 30 from the control unit 40 is in phase with the input voltage. A high frequency switching signal (PWM switching) of 15 KHz is output to the gate terminals of the transistors Q1 and Q2 so as to be close, and a low frequency switching signal of 60 Hz is output to the gate terminals of the transistors Q3 and Q4.

Accordingly, the transistors Q1 and Q2 are turned on in response to the 15 KHz high frequency switching signal (PWM signal) output from the control unit 40, and the transistors Q3 according to the 60 Hz low frequency switching signal on the line voltage output from the control unit 40. Q4) is turned on.

When the transistors Q2 and Q4 are turned on, the transformer T1 acts as a sink so that the current flows through the transistor Q2 and the diode D4 to the transformer as shown in FIG. Accumulate in the transformer T1.

When the transistors Q1 and Q4 are turned on, the DC link voltage becomes smaller than the voltage in front of the transformer T1, and current from the power input terminal 10 does not flow, and current accumulated in the transformer T1 is stored in the transistor ( Q4), since it flows through the battery BT and the transistor Q1, this current is charged in the battery BT, and AC power is converted into DC power.

On the other hand, when the transistors Q1 and Q3 are turned on, current flows through the diode D1 and the transistor Q3 to the transformer T1 as shown in FIG. 5, and this current is accumulated in the transformer T1. .

When the transistors Q2 and Q3 are turned on, since the current accumulated in the transformer T1 flows through the transistor Q2, the battery BT, and the transistor Q3, the current is charged in the battery BT and the AC Power is converted to DC power.

Thereafter, when the transistors Q4 and Q5 are turned on according to the PWM signal from the controller 40, the transistors Q3 to Q6 form a full bridge circuit, so that the transistors Q4 and Q5 and Q3 and Q6 are connected to each other. By alternately turning on or off, the DC power charged in the battery BT is converted into AC power.

AC power converted according to the switching operations of the transistors Q3 to Q6 is applied to the primary side of the transformer T2, stepped up by the winding ratio of the booster transformer T2, and induced to the secondary side, and AC power supplied to the secondary side. Is supplied to the load 70 via a smoothing capacitor C3.

In this case, when the voltage sensing unit 20 and the current sensing unit 30 detect a change in the power supply voltage and the power current that change according to the size of the load 70, and detect the overload, the control unit 40 shows in FIG. 7. According to one inverter control block diagram, the current value at the impulse load 70 is limited to allow stable inverter 60 operation even under overload.

When the size of the load 70 is small, there is no influence on the power factor, so that one side of the control unit 40 is connected to the smoothing capacitor C2 of the power factor compensator 50 and the smoothing capacitor C3 of the inverter 60. By turning on the triac (TRIAC) is connected to the other side to the input power immediately bypasses the output power to the inverter 60 to stop the operation and implemented to operate only the charging circuit of the power factor correction unit 50.

As described above, the transistors Q3 and Q4 implement a common leg switching structure in a three-leg type switching control circuit to cancel each other in the power factor compensation charging mode and the inverter mode. It can be operated to reduce the conduction loss and switching loss caused by the current. Therefore, it is possible to obtain a power factor circuit of high efficiency inverter 60 with an overall power efficiency of 93% or more (90% normal efficiency) while achieving a power factor close to 1 (0.99 or more). It can be implemented.

On the other hand, the output terminal of the inverter 60, in addition to the load 70, any device requiring a constant AC power, such as a rectifier circuit, such as a UPS or a solar cell, or a motor can be connected.

As described above, according to the inverter power supply apparatus according to the present invention, the power factor compensation mode and the inverter mode are operated in a direction in which the power factor compensation mode and the inverter mode cancel each other by three-leg type switching control, so that the conduction loss and the switching caused by the current are reduced. By reducing the loss, the power efficiency can be increased and the power factor can be compensated almost to one.

What has been described above is only one embodiment for implementing the inverter power supply apparatus according to the present invention, the present invention is not limited to the above-described embodiment, and having ordinary knowledge in the art within the technical idea of the present invention Of course, various modifications are possible by the user.

Claims (4)

A power supply for converting a commercial exchange; A power input terminal for supplying commercial AC power, A transformer having an energy accumulation path of alternating current supplied from the power input terminal; Transistors Q1 and Q2 connected in series to the transformer; Transistors Q3 and Q4 connected in parallel to the transistors Q1 and Q2 and converting AC into direct current; A battery connected in parallel between the transistors Q1 and Q2 and the transistors Q3 and Q4 to charge a DC voltage according to a switching operation of the transistors Q1 to Q4; A smoothing capacitor connected to the battery in parallel to reduce a direct current ripple voltage; Transistors Q5 and Q6 connected in parallel to the transistors Q3 and Q4 and converting direct current into alternating current; A transformer having one side connected to the transistors Q5 and Q6 and the other side connected to the transformer; And a controller for outputting a switching signal to the gate terminals of the transistors Q1 to Q6 according to a change in the power voltage and the power current of the power input terminal. The method of claim 1, And a triac for connecting commercial alternating current to an output terminal between the transformer and the transformer. The method of claim 1, And a smoothing capacitor for filtering noise components in parallel with said transformer and said transformer. The method of claim 1, The transistor (Q3, Q4) is operated in a direction to cancel the power factor correction charging mode and the inverter mode in accordance with the switching signal of the control unit.

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