TWI474600B - Single - phase AC - DC power conversion device - Google Patents

Description

Single-phase AC-DC power conversion device

The invention relates to a single-phase AC-DC power conversion device, in particular to an AC voltage input by a single phase, and the AC voltage is converted into a DC voltage through an AC-DC conversion circuit, and the DC voltage is further A single-phase AC-DC power conversion device with high power factor is achieved through an output circuit output.

At present, it is like the Republic of China New Patent Bulletin No. 447187 "Single-phase up/down-voltage AC-DC converter", which mainly provides power semiconductor switching elements, inductors, capacitors, power diodes and a group of converters. The control circuit is configured to convert the input single-phase AC power into a DC voltage output that can be adjusted or lowered. By connecting an inductor in series with the input end of the power supply and the conventional single-phase full-bridge rectifier, two sets of one power diode and one power semiconductor switching element are connected in parallel at the output end of the single-phase full-bridge rectifier. After the series circuit is formed, a capacitor is connected in series at two connection points of the two series circuits, and a series circuit composed of a filter inductor and a filter capacitor is connected in parallel at both ends of one of the power diodes, and the load is The resistor is connected to this filter capacitor. Another feature is that you can use a single-stage conversion to obtain a high-efficiency single-phase up/down AC-to-DC converter, especially when the input current is sine wave and has a unit power factor. .

The technical features revealed in the previous case also have the following shortcomings to be improved:

1. Conventional does not disclose an input voltage that can be applied to general use.

2. The conventional circuit architecture is more complicated.

3. It is not known to use a transformer, so it does not disclose the electrical isolation between its input and output.

Therefore, the present inventors continue to innovate and develop, and further propose a single-phase AC-DC power conversion device, comprising: an input terminal; an AC-DC conversion circuit, the AC-DC conversion circuit electrically connecting the input The AC-DC conversion circuit includes a rectifier, a transformer, and a first inductor, wherein the transformer is electrically connected to the rectifier, and the transformer includes a primary winding and a secondary winding. The first inductor is electrically connected to the secondary winding; an output circuit is electrically connected to the AC-DC conversion circuit; and a single-phase AC voltage is input through the input terminal; The AC voltage is converted to a DC voltage by the AC-DC conversion circuit, and the DC voltage is further output via the output circuit.

The method further includes an input filter electrically connected to the input end and the AC-DC conversion circuit to filter current harmonics at the input end of the AC-DC conversion circuit.

Wherein, the rectifier is a full-wave rectifier.

The full-wave rectifier is a bridge rectifier, and includes a first diode, a second diode, a third diode, and a fourth diode, wherein the first diode An anode end is connected to the cathode end of the second diode and formed with a first node, and a cathode end of the first diode is connected to a cathode end of the third diode and a second node is formed. An anode end of the third diode is connected to a cathode end of the fourth diode and a third node is formed, an anode end of the second diode and an anode end of the fourth diode A fourth node is connected and formed to convert the alternating voltage into the direct current voltage.

The second node is electrically connected to one end of the primary winding, and the other end of the primary winding is electrically connected to one end of the first switching switch, and the first switching switch is electrically connected to the fourth node, and The secondary side winding is in parallel with the first inductance.

The output circuit includes an output diode, an output capacitor, and a load. The first end of the first inductor is electrically connected to the anode end of the output diode, and the cathode end of the output diode is respectively electrically connected. One end of the output capacitor and one end of the load are connected, and the other end of the output capacitor and the other end of the load are electrically connected to the other end of the first inductor.

Further operating in three modes, the sequence is: the first switch is turned on, the first switch is turned off, and the first switch is continuously turned off, wherein when the first switch is turned on, there is a magnetization inductance system The first inductor is connected in parallel, and the AC voltage input by the input terminal transmits energy to the first inductor and the magnetizing inductor, and the current of the first inductor and the current of the magnetizing inductor are linearly reduced, and the output capacitor is The stored energy is released to the load; when the first switch is turned off, the energy stored in the first inductor and the magnetizing inductor is released to the output Receiving the load, and the current of the first inductor and the current of the magnetizing inductance are linearly reduced and reduced to zero; when the first switching switch is continuously turned off, the energy stored by the output capacitor is released to the load .

The effect of the invention is:

1. The present invention can be applied to a general-purpose input voltage (90 to 264 Vrms).

2. Nearly unit power factor of the present invention.

3. The invention has a lower input current total harmonic distortion.

4. The invention has higher efficiency.

5. The invention has a simple structure.

6. The input and output of the present invention have electrical isolation effects.

7. The invention provides a single-phase AC-DC power conversion device with high power factor, which has a simple structure and can transmit residual magnetism to the output side in each switching cycle without requiring multiple sets of windings.

(1) ‧‧‧ input

(11)‧‧‧Input filter

(2) ‧‧‧AC current conversion circuit

(21)‧‧‧Bridge rectifiers

(22)‧‧‧Transformers

(3)‧‧‧Output circuit

(D1)‧‧‧First Diode

(D2) ‧ ‧ second diode

(D3)‧‧‧ Third Dipole

(D4) ‧ ‧ fourth diode

(N1)‧‧‧ primary winding

(N2)‧‧‧secondary winding

(Lm)‧‧‧Magnetic Inductance

(iLm)‧‧‧Magnetic inductor current

(L ₁ )‧‧‧First inductance

(iL1)‧‧‧First inductor current

(S ₁ )‧‧‧First switch

(D _o )‧‧‧ Output diodes

(C _o )‧‧‧output capacitor

(R)‧‧‧load

(ND1)‧‧‧first node

(ND2)‧‧‧second node

(ND3) ‧‧‧ third node

(ND4) ‧ ‧ fourth node

[First figure] is a schematic diagram of the circuit configuration of the present invention.

[Second figure] is an equivalent circuit diagram of the present invention.

[Third image] is the main waveform diagram of a single switching cycle when the input voltage is positive half-wave.

[Fourth figure] is the first operation mode current path diagram of the present invention.

[Fifth Diagram] is a second operation mode current path diagram of the present invention.

[Sixth Diagram] is a third operational mode current path diagram of the present invention.

[Seventh] is a waveform diagram of the input voltage of 115Vrms, output voltage of 100V _DC, and output power of 100W, illustrating the waveforms of the input voltage and the input current.

[Eighth image] is another waveform diagram of the input voltage of 115Vrms, output voltage of 100V _DC and output power of 100W, illustrating the current values of the primary winding and the secondary winding of the transformer.

[Ninth diagram] is a waveform diagram of the input voltage of 230Vrms, output voltage of 100V _DC, and output power of 100W, illustrating the waveforms of the input voltage and the input current.

[Tenth] is another waveform diagram of the input voltage of 230Vrms, output voltage of 100V _DC and output power of 100W, illustrating the current values of the primary winding and the secondary winding of the transformer.

[11th] is a power factor curve of the invention measured at an input voltage of 90 to 264 Vrms, an output voltage of 100 V _DC, and different output powers.

[Twelfth Figure] is a graph of the total harmonic distortion of the input current measured at an input voltage of 90 to 264 Vrms, an output voltage of 100 V _DC, and different output powers.

[Thirteenth] is a graph showing the efficiency of the invention measured at an input voltage of 90 to 264 Vrms, an output voltage of 100 V _DC, and different output powers.

Combining the above technical features, the main effects of the present invention will be clearly shown in the following embodiments.

The invention is a single-phase AC-DC power conversion device, and please refer to the first The first diagram is a schematic diagram of the circuit architecture of the present invention, and the second diagram is an equivalent circuit diagram of the present invention, which includes: an input terminal (1), the input terminal (1) Mainly inputting a single-phase AC voltage, and the input terminal (1) is connected to an input filter (11).

An AC-DC conversion circuit (2), the AC-DC conversion circuit (2) is electrically connected to the input filter (11), and the AC-DC conversion circuit (2) comprises a bridge rectifier (21) a transformer (22) and a first inductor (L ₁ ), the bridge rectifier (21) is a full-wave rectifier, and the bridge rectifier (21) includes a first diode (D1), a second diode (D2), a third diode (D3), and a fourth diode (D4), wherein the anode end of the first diode (D1) and the second second The cathode end of the polar body (D2) is connected and formed with a first node (ND1), and the cathode end of the first diode (D1) is connected to the cathode end of the third diode (D3) and formed with a cathode a second node (ND2), an anode end of the third diode (D3) is connected to a cathode end of the fourth diode (D4) and formed with a third node (ND3), the second An anode end of the polar body (D2) is connected to an anode end of the fourth diode (D4) and forms a fourth node (ND4) for converting the alternating voltage into the direct current voltage, and the transformer (22) electrically connecting the bridge rectifier (21), said transformer (22) comprises a primary winding (N1) and a secondary winding (N2), the first inductor (L ₁₎ based electrically connected to the secondary winding (N2) The second node (ND2) is electrically connected to one end of the primary winding (N1), and the other end of the primary winding (N1) is electrically connected with a first switching switch. (S ₁ ), the first switch (S ₁ ) is electrically connected to the fourth node (ND4), and the secondary winding (N2) is connected in parallel with the first inductor (L ₁ ) .

An output circuit (3) electrically connected to the AC-DC conversion circuit (2), the output circuit (3) comprising an output diode, an output capacitor and a load, One end of the first inductor is electrically connected to the anode end of the output diode (D _o ), and the cathode end of the output diode (D _o ) is electrically connected to one end of the output capacitor (C _o ) and One end of the load (R), the other end of the output capacitor (C _o ) and the other end of the load (R) are electrically connected to the other end of the first inductor (L ₁ ), respectively, mainly through the input end (1) Inputting a single-phase AC voltage, and the AC voltage is converted into a DC voltage via the AC-DC conversion circuit (2), and the DC voltage is further output via the output circuit (3).

Furthermore, the state of use is shown in the third to sixth figures, wherein the third figure is the main waveform diagram of a single switching period when the input voltage is positive half-wave. The invention adopts pulse width modulation technology and operates in a discontinuous conduction mode to achieve high power factor and low input current total harmonic distortion. Since the input voltage has a positive and negative half-wave symmetry relationship, the operating principle of the present invention only discusses the positive half-wave, which is described as follows:

Mode 1: In the interval [kTs, tk1], the first switch (S ₁ ) is turned on, and the current path is as shown in the fourth figure. The input power is passed through the ideal transformer (22) to the magnetizing inductance (L _m ) of the transformer and the first The inductor (L ₁ ) transmits energy, so the magnetizing inductor current (iLm) and the first inductor current (iL1) of the magnetizing inductance (L _m ) increase linearly. Since the magnetizing inductance (L _m ) is much larger than the first inductance (L ₁ ), the magnetizing inductor current (iLm) is much smaller than the first inductor current (iL1), and the energy stored in the magnetizing inductance (L _m ) is remanence, The energy stored by the output capacitor (C _o ) is released to the load (R). When the first changeover switch (S ₁ ) is turned off, the operation mode ends.

Mode 2: In the interval [tk1, tk2], the first switching switch (S ₁ ) is turned off, and the current path is as shown in the fifth figure, and the energy stored in the magnetizing inductance (L _m ) and the first inductance (L ₁ ) is released to The output capacitor (C _o ) and the load (R), so the magnetizing inductor current (iLm) and the first inductor current (iL1) are linearly reduced, and when the magnetizing inductor current (iLm) and the first inductor current (iL1) are reduced to zero At this time, the operation mode ends, so the residual magnetization of the transformer (22) can be released every switching cycle.

Mode 3: In the interval [tk2, (k+1) Ts], the first switching switch (S ₁ ) is continuously turned off, and the current path is as shown in the sixth figure. At this time, the energy stored in the output capacitor (C _o ) is released to the load (R). When the first switch (S ₁₎ is turned on again at the beginning of the next switching cycle, the end of the operation mode.

Furthermore, please refer to the seventh and eighth figures, which are the waveforms of the input voltage of 115Vrms, the output voltage of 100V _DC , and the output power of 100W. The seventh figure shows that the input voltage and the input current are nearly in phase. The eighth figure shows the waveform of the primary side current [iN1] and the secondary side current [iN2] of the transformer (22). The secondary side current [iN2] shows that the residual magnetization of the transformer (22) is in each switching cycle. Can be released.

Furthermore, please refer to the ninth and tenth diagrams, which are waveforms of input voltage 230Vrms, output voltage 100V _DC , and output power 100W. The ninth diagram shows that the input voltage and input current are nearly in phase. The tenth figure shows the waveform of the primary side current [iN1] and the secondary side current [iN2] of the transformer (22). The secondary side current [iN2] shows that the residual magnetization of the transformer (22) is in each switching cycle. Can be released.

Furthermore, please refer to the eleventh to thirteenth figures, which is the general input voltage of 90~264Vrms, the output voltage of 100V _DC , and the measured data under different output powers. It can be seen that the power factor is higher than 0.96. The total harmonic distortion of the input current is less than 5.8% and the maximum efficiency is 91.5%.

In view of the foregoing description of the embodiments, the operation and the use of the present invention and the effects of the present invention are fully understood, but the above described embodiments are merely preferred embodiments of the present invention, and the invention may not be limited thereto. Included within the scope of the present invention are the scope of the present invention.

(1) ‧‧‧ input

(11)‧‧‧Input filter

(2) ‧‧‧AC current conversion circuit

(22)‧‧‧Transformers

(3)‧‧‧Output circuit

(D1)‧‧‧First Diode

(D2) ‧ ‧ second diode

(D3)‧‧‧ Third Dipole

(D4) ‧ ‧ fourth diode

(N1)‧‧‧ primary winding

(N2)‧‧‧secondary winding

(L ₁ )‧‧‧First inductance

(S ₁ )‧‧‧First switch

(D _o )‧‧‧ Output diodes

(C _o )‧‧‧output capacitor

(R)‧‧‧load

(ND1)‧‧‧first node

(ND2)‧‧‧second node

(ND3) ‧‧‧ third node

(ND4) ‧ ‧ fourth node

Claims (4)

A single-phase AC-DC power conversion device includes: an input terminal; an AC-DC conversion circuit, the AC-DC conversion circuit is electrically connected to the input end, and the AC-DC conversion circuit includes a rectifier a transformer and a first inductor, wherein the transformer is electrically connected to the rectifier, the transformer includes a primary side winding and a secondary side winding, and the first inductor is electrically connected to the secondary side a winding, wherein the rectifier is a full-wave rectifier, the full-wave rectifier is a bridge rectifier, comprising a first diode, a second diode, a third diode and a fourth diode a body, wherein an anode end of the first diode is connected to a cathode end of the second diode and a first node is formed, a cathode end of the first diode and the third diode The cathode end is connected and formed with a second node, and the anode end of the third diode is connected to the cathode end of the fourth diode and forms a third node, and the anode end of the second diode And the fourth diode The anode end is connected and formed with a fourth node, thereby converting the alternating current voltage into the direct current voltage, wherein the second node is electrically connected to one end of the primary side winding, and the other end of the primary side winding is electrically connected a first switching switch is electrically connected to the fourth node, and the secondary winding is connected in parallel with the first inductor; an input filter is electrically connected to the input And the AC-DC conversion circuit for current harmonic filtering at the input end of the AC-DC conversion circuit In addition to an output circuit, the output circuit is electrically connected to the AC-DC conversion circuit, wherein the output circuit includes an output diode, an output capacitor, and a load, and the first inductor is electrically connected at one end. Connecting the anode end of the output diode, the cathode end of the output diode is electrically connected to one end of the output capacitor and one end of the load, and the other end of the output capacitor and the other end of the load are respectively electrically Connecting the other end of the first inductor; inputting a single-phase AC voltage through the input terminal, and the AC voltage is converted into a DC voltage through the AC-DC conversion circuit, and the DC voltage is further transmitted through the output Circuit output. The single-phase AC-DC power conversion device according to claim 1 further operates in three modes, in sequence: the first switch is turned on, the first switch is turned off, and the first switch is continuously turned off, wherein When the first switch is turned on, a magnetizing inductance is connected in parallel with the first inductor, and an alternating voltage input from the input terminal transmits energy to the first inductor and the magnetizing inductor, and the current of the first inductor is The current of the magnetizing inductor decreases linearly, and the energy stored by the output capacitor is released to the load; when the first switching switch is turned off, the energy stored in the first inductor and the magnetizing inductor is released to the An output capacitor and the load, and the current of the first inductor and the current of the magnetizing inductor linearly decrease and fall to zero; when the first switching switch is continuously turned off, the energy stored by the output capacitor is released to the load. A single-phase AC-DC power conversion device includes: an input terminal; an AC-DC conversion circuit, the AC-DC conversion circuit is electrically connected to the input end, and the AC-DC conversion circuit includes a rectifier ,One a transformer and a first inductor, wherein the transformer is electrically connected to the rectifier, the transformer includes a primary side winding and a secondary side winding, and the first inductor is electrically connected to the secondary side winding, Wherein, the rectifier is a full-wave rectifier, and the full-wave rectifier is a bridge rectifier, comprising a first diode, a second diode, a third diode and a fourth diode. The anode end of the first diode is connected to the cathode end of the second diode and forms a first node, and the cathode end of the first diode and the cathode of the third diode Extremely connected and formed with a second node, an anode end of the third diode is connected to a cathode end of the fourth diode and a third node is formed, and an anode end of the second diode The anode end of the fourth diode is connected and formed with a fourth node, thereby converting the alternating voltage into the direct current voltage, wherein the second node is electrically connected to one end of the primary winding, the first time The other end of the side winding is electrically connected to have a first Rechanging a switch, the first switch is electrically connected to the fourth node, and the secondary winding is connected in parallel with the first inductor; and an output circuit is electrically connected to the AC a DC conversion circuit, wherein the output circuit includes an output diode, an output capacitor, and a load, and one end of the first inductor is electrically connected to an anode terminal of the output diode, and the output diode The cathode end is electrically connected to one end of the output capacitor and one end of the load, and the other end of the output capacitor and the other end of the load are electrically connected to the other end of the first inductor respectively; A single phase alternating voltage, and the alternating voltage is converted to a direct current voltage by the alternating current to direct current conversion circuit, and the direct current voltage is further output via the output circuit. The single-phase AC-DC power conversion device according to claim 3 is further operated at The three modes are sequentially: the first switching switch is turned on, the first switching switch is turned off, and the first switching switch is continuously turned off, wherein, when the first switching switch is turned on, there is a magnetizing inductance system and the first The inductors are connected in parallel, and the AC voltage input by the input terminal transmits energy to the first inductor and the magnetizing inductor, and the current of the first inductor and the current of the magnetizing inductor are linearly reduced, and the energy stored by the output capacitor Is released to the load; when the first switch is turned off, the energy stored in the first inductor and the magnetizing inductor is released to the output capacitor and the load, and the current of the first inductor and the magnetizing inductance The current system decreases linearly and drops to zero; the operation stores the energy stored by the output capacitor to the load when the first switch is continuously turned off.