TWI482406B - Single-stage three-phase AC-DC converters for small wind power generation systems - Google Patents

Description

Single-stage three-phase AC-DC converter for small wind power generation systems

The present invention relates to a power converter and a wind power generation system, and more particularly to a single-stage three-phase AC-DC converter applied to a small-scale wind power generation system.

For example, the Republic of China Invention Patent Publication No. 200916655 "Wind-powered wind power generation device" has two first and second paths fed into the mains, wherein the first path can be at a sufficient wind speed. When the blade of a blade rotor is rotated by the wind, a generator is used to generate electricity by its pivot. The generator can supply sufficient voltage to a DC/AC converter for conversion after passing through a three-phase AC/DC rectifier. And finally paralleling the mains; in addition, if the low speed is reached at low wind speed or the maximum static friction is not overcome, the second path is first performed, and the mains supply is first supplied to a driver to drive the generator. When the motor reaches the preset release speed point, that is, after the wind power generator overcomes the maximum static friction force, the driver is cut off and restored to the first path of feeding the mains, so that the wind energy at low wind speed can be increased. Usage rate.

Moreover, the conventional wind power generation system does not disclose the problem of using an power factor correction circuit to improve the input current pulse wave caused by the bridge rectifier in the wind power generation system. Therefore, the inventors have devoted themselves to research and development. A single-stage three-phase AC-DC converter applied to a small wind power generation system.

The invention provides a single-stage three-phase AC-DC converter applied to a small-scale wind power generation system, which comprises: a three-phase input voltage terminal; a power factor correction circuit, wherein the power factor correction circuit is electrically connected to the three a phase input voltage terminal; a conversion circuit electrically connected to the power factor correction circuit; wherein the power factor correction circuit reduces a large current pulse generated by the three-phase input voltage terminal, and then The conversion circuit performs voltage conversion.

Further, the power factor correction circuit comprises a filter circuit, three first inductors and a three-phase bridge rectifier, and one end of the filter circuit is electrically connected to the three-phase input voltage terminal, and the other end of the filter circuit is electrically connected. The three first inductors are electrically connected to the three-phase bridge rectifier, and the three-phase bridge rectifier is electrically connected to the conversion circuit.

Further, the filter circuit includes three filter inductors and three filter capacitors, and each of the filter inductors is connected to the filter capacitors in series.

Further, the conversion circuit includes a switch, a first diode, a second diode, a third diode, a fourth diode, a first capacitor, a second capacitor, and a second a three-capacitor, a primary-side inductor, a secondary-side inductor, and an output load resistor, wherein the primary-side inductor and the secondary-side inductor are coupled with each other, and the anode terminal and the second diode of the first diode The anode ends of the diodes are connected to each other, and the cathode end of the first diode is connected to the anode end of the third diode, the end of the primary side inductor and the 汲 terminal of the switch, and the other end of the primary side inductor is connected to the first end Bipolar a first node is formed at the cathode end, and the first node is connected to one end of the first capacitor and one end of the second capacitor, and the cathode end of the third diode and the other end of the second capacitor and the third capacitor end Connected to each other, the cathode end of the third diode is connected to one end of the secondary side inductor, and the other end of the second side inductor is connected to the anode end of the fourth diode, and the other end of the third capacitor is opposite to the first The cathode ends of the quadrupoles are connected to each other and connected to one end of the output load resistor, and the source terminal of the switch is connected to the other end of the first capacitor and the other end of the output load resistor.

The advantages of the invention are:

1. The invention can convert the voltage and frequency of the variation range of the output of the generator in the wind power unit into a stable DC high voltage.

2. The invention has the function of power factor correction to improve the problem that the input current pulse is too large.

3. In the conversion circuit of the present invention, three output capacitors (a first capacitor, a second capacitor, and a third capacitor) are stacked to increase the output voltage.

4. The switching circuit in the conversion circuit of the present invention has a voltage clamping function, and its voltage stress is smaller than the output voltage, so that a metal oxide semiconductor field effect transistor (MOSFET) with a lower rated voltage and a low on-resistance can be selected to Reduce conduction losses.

5. The primary side inductance and the secondary side inductance in the conversion circuit of the present invention are coupled inductors, and the leakage inductance energy of the coupled inductor has a recovery function.

(1) ‧‧‧ wind turbines

(11)‧‧‧Generator

(2) ‧‧‧Three-phase input voltage terminal

(3)‧‧‧Power factor correction circuit

(31)‧‧‧Filter circuit

(32)‧‧‧First inductance

(33)‧‧‧Three-phase bridge rectifier

(4)‧‧‧Transition circuit

(5)‧‧‧Inverter

(6)‧‧‧Output filter

(7)‧‧‧Output voltage terminal

(S ₁ )‧‧‧Switch

(L _m )‧‧‧Magnetic inductance

(L _f )‧‧‧Filter inductor

(N ₁ )‧‧‧ primary side inductance

(N ₂ )‧‧‧secondary inductance

(L _k1 )‧‧‧Primary leakage inductance

(L _k2 )‧‧‧Second-side leakage inductance

(C _f )‧‧‧Filter capacitor

(C ₁ )‧‧‧First Capacitor

(C ₂ )‧‧‧second capacitance

(C ₃ )‧‧‧ third capacitor

(D ₁ )‧‧‧First Diode

(D ₂ )‧‧‧Secondary

(D ₃ )‧‧‧ Third Dipole

(D ₄ )‧‧‧Fourth diode

(R)‧‧‧Output load resistor

(ND1)‧‧‧first node

The first figure is an architectural diagram of the small wind power generation system of the present invention.

The second figure is a block diagram of a single-stage three-phase AC-DC converter of the present invention.

The third figure is a detailed structural circuit diagram of the single-stage three-phase AC-DC converter of the present invention.

The fourth figure is an equivalent circuit diagram of the single-stage three-phase AC-DC converter of the present invention.

The fifth picture is a waveform diagram of the three-phase power supply voltage.

The sixth diagram is a waveform diagram of the input phase voltage, the switching gate threshold trigger signal, and the unfiltered input current.

Figure 7A is a current path diagram of the operation mode of the single-stage three-phase AC-DC converter of the present invention.

FIG seventh B-phase single-stage of the present invention the operation mode of the AC-DC converter of a current path diagram illustrating a current path of each switching element when the switch S ₁ is turned on.

Figure 8A is a current path diagram of the operation mode 2 of the single-stage three-phase AC-DC converter of the present invention.

FIG line VIII B of the three-phase single-stage mode of operation of the present invention, AC-DC converter of the two current paths diagram illustrating a current path of the switching element when the respective switch S ₁ is turned on continuously in the pattern.

The ninth A diagram is a current path diagram of the operation mode 3 of the single-stage three-phase AC-DC converter of the present invention.

Ninth B of FIG three-phase single-stage mode of operation of the present invention, AC-DC converter of a current path ter diagram illustrating a current path of each switching element when the switch S ₁ is turned off.

The tenth A is a current path diagram of the operation mode of the single-stage three-phase AC-DC converter of the present invention.

FIG tenth line B of the three-phase single-stage mode of operation of the present invention, AC-DC converter of the current path of the four diagram illustrating a current path of each switching element of the switch S ₁ is turned off after continuous mode three.

The eleventh A is a current path diagram of the operation mode 5 of the single-stage three-phase AC-DC converter of the present invention.

FIG eleventh line B of the three-phase single-stage mode of operation of the present invention, AC-DC converter of the current paths of the five diagram illustrating a current path switch S on the various elements of _an off duration after Mode 4.

The twelfth A is a current path diagram of the operation mode 6 of the single-stage three-phase AC-DC converter of the present invention.

FIG twelfth line B of the three-phase single-stage mode of operation of the present invention, AC-DC converter of the six current path diagram illustrating a current path switch S on the various elements of _a continuous off mode after five.

The thirteenth diagram is the main waveform diagram of the single-stage three-phase AC-DC converter of the present invention in a single switching period of the interval [0, π/6].

FIG fourteenth line of the present invention operates in a generator of the wind turbines within the output line voltage is 80V, the line frequency 62Hz, the output voltage of the three-phase single-stage AC-DC converter of the present invention and the full 400V _DC An analog waveform diagram of the generator output phase voltage e _a and the output phase current i _a with an output power of 600 W.

FIG fifteenth lines of the present invention operates in a generator of the wind turbines within the output line voltage is 80V, the line frequency 62Hz, the output voltage of the three-phase single-stage AC-DC converter of the present invention and the full 400V _DC An analog waveform diagram of the generator output phase currents i _a , i _{b ,} and i _c of an output power of 600 W.

The sixteenth figure is the output voltage of the single-stage three-phase AC-DC converter of the present invention having a line voltage of 80V and a line voltage frequency of 62 Hz, and the output voltage of the single-stage three-phase AC-DC converter of the present invention is 400V _DC and fully loaded. An analog waveform diagram of the voltages V _c1 , V _{c2 ,} and V _c3 on the first capacitor, the second capacitor, and the third capacitor in the conversion circuit of the output power of 600 W.

FIG seventeenth operation of the generator system of the present invention, the wind turbines within the output line voltage is 80V, the line frequency 62Hz, the output voltage of the three-phase single-stage AC-DC converter of the present invention and the full 400V _DC An analog waveform diagram of the output voltage V _o and the output current I _o on the output load in the conversion circuit of the output power of 600 W.

The eighteenth figure is that the line voltage outputted by the generator operating in the wind power unit is 20V, the line voltage frequency is 14 Hz, and the output voltage of the single-stage three-phase AC-DC converter of the present invention is 400V _DC and full load. An analog waveform diagram of the generator output phase voltage e _a and the output phase current i _a with an output power of 30 W.

FIG nineteenth operation of the generator system of the present invention, the wind turbines within the output line voltage is 20V, the line frequency 14Hz, the output voltage of the three-phase single-stage AC-DC converter of the present invention and the full 400V _DC An analog waveform diagram of the output phase currents i _a , i _{b ,} and i _c of the generator output power of 30 W.

The twentieth figure shows that the line voltage output by the generator operating in the wind power unit is 20V, the line voltage frequency is 14 Hz, and the output voltage of the single-stage three-phase AC-DC converter of the present invention is 400V _DC and full load. An analog waveform diagram of the voltages V _c1 , V _{c2 ,} and V _c3 of the first capacitor, the second capacitor, and the third capacitor in the conversion circuit of the output power of 30 W.

The twenty-first figure is the output voltage of the single-stage three-phase AC-DC converter of the present invention having a line voltage of 20V, a line voltage frequency of 14 Hz, and a output voltage of 400 V _DC of the single-stage three-phase AC-DC converter of the present invention. An analog waveform diagram of the output voltage V _o and the output current I _o on the output load of the conversion circuit with a full load output of 30 W.

The technical features and enhancements of the present invention are clearly shown in conjunction with the preferred embodiments of the following drawings. The present invention is a single-stage three-phase AC-DC converter applied to a small wind power generation system, please refer to The first figure shows the architecture of the single-stage three-phase AC-DC converter applied to a small-scale wind power generation system, which includes a wind turbine (1), a three-phase input voltage terminal (2), a power factor correction circuit (3), a conversion circuit (4), an inverter (5), an output filter (6) and an output voltage terminal (7), and the three-phase input voltage terminal (2) One end of the three-phase input voltage terminal (2) is electrically connected to the power factor correction circuit (3), and the power factor correction circuit (3) is electrically connected. The conversion circuit (4) is electrically connected to the inverter (5), and the converter (5) is electrically connected to the output filter (6), and the output filter ( 6) electrically connecting the output voltage terminal (7), wherein the wind power unit (1) further comprises a generator (11).

Furthermore, please refer to the second figure, which is a system block diagram of the single-stage three-phase AC-DC converter of the present invention, which includes the three-phase input voltage terminal (2) and a power factor correction circuit ( 3) and a conversion circuit (4), wherein the three-phase input voltage terminal (2) is electrically connected to the power factor correction circuit (3), and the power factor correction circuit (3) is electrically connected to the conversion circuit (4) ).

For further explanation, please refer to the third and fourth figures, which is a detailed circuit diagram of a single-stage three-phase AC-DC converter, which includes the aforementioned three-phase input voltage terminal (2) and a power factor correction circuit (3). And a conversion circuit (4), wherein the power factor correction circuit (3) comprises a filter circuit (31), three first inductors (32) and a three-phase bridge rectifier (33), and the filter circuit (31) Further comprising three filter inductors (L _f ) and three filter capacitors (C _f ), and each of the filter inductors (L _f ) is connected in series with the filter capacitors (C _f ), and one end of the filter circuit (31) Electrically connecting the three-phase input voltage terminal (2), the other end of the filter circuit (31) is electrically connected to the three first inductors (32), and the three first inductors (32) are electrically connected to the third inductor (32). A three-phase bridge rectifier (33), and the three-phase bridge rectifier (33) is electrically connected to the conversion circuit (4).

The conversion circuit (4) includes a switch (S ₁ ), a first diode (D ₁ ), a second diode (D ₂ ), a third diode (D ₃ ), and a a fourth diode (D ₄ ), a first capacitor (C ₁ ), a second capacitor (C ₂ ), a third capacitor (C ₃ ), a primary side inductance (N ₁ ), and a second time a side inductor (N ₂ ) and an output load resistor (R), wherein the primary side inductance (N ₁ ) and the secondary side inductance (N ₂ ) are coupled with each other, and the first diode (D ₁ ) The anode end is connected to the anode end of the second diode (D ₂ ), and the cathode end of the first diode (D ₁ ) is connected to the anode end and the primary side of the third diode (D ₃ ) One end of the inductor (N ₁ ) and a drain of the switch (S ₁ ), the other end of the primary side inductor (N ₁ ) is connected to the cathode end of the second diode (D ₂ ) and forms a first female node (ND1), and the first node (ND1) connected to the first capacitor (C ₁₎ and an end of the second capacitor (C ₂₎ at one end, and the third diode (D ₃₎ of the terminal a second capacitor (C ₂₎ and the other end of the third capacitor (C ₃₎ connected to each other at one end, and the female of the third diode (D ₃₎ connected to the terminal A secondary side inductor (N ₂₎ at one end, and (N ₂₎ and the other end connected to the anode terminal of the secondary side inductor of the fourth diode (D ₄₎ of, and the third capacitor (C ₃₎ and the other end The cathode ends of the fourth diode (D ₄ ) are connected to each other and connected to one end (R) of the output load resistor, and the source terminal (Source) of the switching switch (S ₁ ) and the other end of the first capacitor (C ₁ ) And the other end of the output load resistor (R) is connected to each other.

The fourth figure is the equivalent circuit diagram of the third figure. The coupled inductor includes an ideal transformer, a magnetizing inductance (L _m ), a primary side leakage inductance (L _k1 ), and a secondary side leakage inductance (L _k2 And the primary side leakage inductance (L _k1 ) is connected to the cathode end of the first diode (D ₁ ) and the primary side inductance (N ₁ ) end, and the secondary side leakage inductance (L _k2 ) is connected The other end of the secondary side inductor (N ₂ ) and the anode end of the fourth diode (D ₄ ), and the magnetizing inductance (L _m ) is connected across the end of the primary side inductor (N ₁ ) and the first On the node (ND1).

Furthermore, the fifth diagram is a waveform diagram of the three-phase power supply voltage, including the phase voltage e _a , the phase voltage e _b and the phase voltage e _c , and the sixth diagram is the input phase voltage e _a , the switch (S ₁ The waveform of the voltage of the gate trigger signal V _gs1 and the unfiltered input current i _La .

The operation principle of the single-stage three-phase AC-DC converter of the present invention has the following six modes, please refer to the seventh picture A, the seventh B picture, the eighth A picture, the eighth B picture, and the ninth A picture. , ninth B, tenth A, tenth B, eleventh, eleventh, twelfth, and twelfth. The thirteenth picture is the main waveform of the single switching period of the converter in the interval [0, π/6] [as shown in the fifth figure], and the description is as follows:

Mode 1, [kT _s , t _k1 ]: the switch (S ₁ ) is turned on, and its current path is as shown in the seventh A and seventh B, and the three first inductors (32) start to store energy, so three The absolute values of the currents i _La , i _{Lb ,} and i _Lc of the first inductor (32) begin to increase, and the absolute value of the current i _Lb is the sum of the absolute values of the current i _La and the current i _Lc . And the magnetizing inductance (L _m ) and the primary side leakage inductance (L _k1 ) of the coupled energy (the primary side inductance (N ₁ ) and the secondary side inductance (N ₂ )) of the first capacitor (C ₁ ) The energy is released, and the energy stored in the secondary side leakage inductance (L _k2 ) is recovered to the third capacitance (C ₃ ), so the current (i _Lm ) of the magnetizing inductance (L _m ) and the primary side leakage inductance (L _{k1 )} ) of current (i _Lk1) is incremented, and the secondary-side leakage inductance (L _k2) of the current (i _Lk2) is decremented. The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are stacked and deliver energy to the output load resistor (R). When the primary side leakage inductance (L _k1 ) current (i _Lk1 ) is equal to the magnetizing inductance (L _m ) current (i _Lm ), the energy stored in the secondary side leakage inductance (L _k2 ) is also After the recycling is completed, the mode of this operation is over.

Mode 2, [t _k1 , t _k2 ]: The switching switch (S ₁ ) is continuously turned on, and its current path is as shown in FIG. 8A and FIG. The three first inductors (32) continue to store energy, so the absolute values of the currents i _La , i _Lb and i _Lc of the three first inductors (32) continue to increase, and the absolute value of the current i _Lb is the current i _La and the current i _The sum of the absolute values of _Lc . The energy stored in the first capacitor (C ₁ ) is continuously released to the magnetizing inductance (L _m ) and the primary side leakage inductance (L _k1 ), so the current (i _Lm ) of the magnetizing inductance (L _m ) and the primary side The leakage inductance (L _k1 ) current (i _Lk1 ) continues to increase. The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are superimposed to deliver energy to the output load resistor (R), and the mode 2 of the operation ends at the switch (S) ₁ ) At the end of the day.

Mode three, [t _k2 , t _k3 ]: The switch (S ₁ ) is turned off, and its current path is as shown in FIG. 9A and FIG. Stored in the three first inductors (32) to the first capacitor (C ₁ ), so the absolute values of the currents i _La , i _Lb and i _Lc of the three first inductors (32) are decremented, and the current i _Lb The absolute value is the sum of the absolute values of the current i _La and the current i _Lc . The energy stored in the magnetizing inductance (L _m ) and the primary side leakage inductance (L _k1 ) is released to the second capacitor (C ₂ ), and the energy stored in the magnetizing inductance (L _m ) is coupled to the inductor [primary side] The inductance (N ₁ ) and the secondary side inductance (N ₂ ) are released to the secondary side leakage inductance (L _k2 ) and the third capacitance (C ₃ ), and thus the magnetizing inductance (L _m ) current (i _{Lm )} And the primary side leakage inductance (L _k1 ) current (i _Lk1 ) is decremented, and the secondary side leakage inductance (L _k2 ) current (i _Lk2 ) is incremented, and the primary side leakage inductance is stored at this time (L _{k1 )} The energy is recovered to the second capacitor (C ₂ ). The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are stacked to deliver energy to the output load resistor (R). Mode 3 of this operation ends when the energy stored in the first inductor (32) of phase A is released.

Mode 4, [t _k3 , t _k4 ]: The switch (S ₁ ) is continuously turned off, and its current path is as shown in FIG. 10A and FIG. The first inductor (32) stored in the B phase and the C phase is continuously discharged to the first capacitor (C ₁ ), so the absolute values of the currents i _Lb and i _{Lc are} decremented, and the absolute value of the current i _Lb is equal to the absolute value of the current i _Lc . The energy stored in the magnetizing inductance (L _m ) and the primary side leakage inductance (L _k1 ) is continuously released to the second capacitor (C ₂ ), and the energy stored in the magnetizing inductance (L _m ) is continuously released through the coupled inductor To the secondary side leakage inductance (L _k2 ) and the third capacitance (C ₃ ), the current (i _Lm ) of the magnetizing inductance (L _m ) and the current of the primary side leakage inductance (L _k1 ) (i _Lk1 ) Continuously decreasing, and the current (i _Lk2 ) of the secondary side leakage inductance (L _k2 ) continues to increase, and the primary side leakage inductance (L _k1 ) stored at this time continues to recover energy to the second capacitance (C ₂ ). The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are stacked to deliver energy to the output load resistor (R). Mode 4 of this operation ends with the energy recovery stored in the primary side leakage (L _k1 ).

Mode 5, [t _k4 , t _k5 ]: The switch (S ₁ ) is continuously turned off, and its current path is as shown in FIG. 11A and FIG. 11B. The first inductor (32) stored in the B phase and the C phase is continuously discharged to the first capacitor (C ₁ ), so the absolute values of the current i _Lb and the current i _Lc continuously decrease, and the absolute value of the current i _Lb is equal to the current i _Lc Absolute value. The magnetizing inductance (L _m ) is released in series by the secondary side inductance (N ₂ ) of the coupled inductor and the secondary side leakage inductance (L _k2 ) to the third capacitor (C ₃ ), and thus the magnetizing inductance (L _{m )} The current (i _Lm ) and the secondary side leakage inductance (L _k2 ) current (i _Lk2 ) are decremented, and the energy stored in the secondary side leakage inductance (L _k2 ) is recovered to the third capacitor (C) ₃ ). The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are stacked to deliver energy to the output load resistor (R). Mode 5 of this operation ends when the energy stored in phase B and phase C first inductor (32) is released.

Mode six, [t _k5 , (k+1)T _s ]: The switching switch (S ₁ ) is continuously turned off, and its current path is as shown in FIG. 12A and FIG. The magnetizing inductance (L _m ) is continuously released by the secondary side inductance (N ₂ ) of the coupled inductor and the secondary side leakage inductance (L _k2 ) to the third capacitor (C ₃ ), and thus the magnetizing inductance (L) _m) of the current (i _Lm) and the secondary side leakage inductance (L _k2) of the current (i _Lk2) and reduced in, then stored in the secondary-side leakage inductance (L _k2) continuous recovery of energy to the third Capacitance (C ₃ ). The first capacitor (C ₁ ), the second capacitor (C ₂ ), and the third capacitor (C ₃ ) are connected to deliver the energy to the output load resistor (R) when the switch (S ₁ ) is switched next. When the cycle is turned on again, mode 6 of this operation ends.

Furthermore, referring to FIG. 14, the line voltage of the generator (11) operating in the wind turbine (1) of the present invention is 80V, the line voltage frequency is 62 Hz, and the single stage of the present invention. The output voltage of the three-phase AC-DC converter is 400V _DC and the output voltage of the generator output phase voltage e _a and the output phase current i _a is 600W.

The fifteenth figure is a single-stage three-phase AC-DC converter of the present invention, which has a line voltage of 80 V and a line voltage frequency of 62 Hz outputted by the generator (11) operating in the wind power unit (1). The output waveform of the output voltage of 400V _DC and the output of the generator with _a full load output of 600W is the analog waveform of the phase currents i _a , i _b and i _c .

The sixteenth figure is the single-stage three-phase AC-DC converter of the present invention, which has a line voltage of 80V and a line voltage frequency of 62 Hz outputted by the generator (11) operating in the wind power unit (1). The analog waveforms of the voltages V _c1 , V _{c2 ,} and V _c3 on the first capacitor, the second capacitor, and the third capacitor in the conversion circuit of the output voltage of 400V _DC and the full load output power of 600W.

The seventeenth figure is the single-stage three-phase AC-DC converter of the present invention, which has a line voltage of 80V and a line voltage of 62 Hz outputted by the generator (11) operating in the wind power unit (1). The output waveform of the output voltage V _o and the output current I _o on the output load resistor (R) in the conversion circuit of the output voltage of 400V _DC and the full load output power of 600W.

18 is a single-stage three-phase AC-DC conversion of the present invention. The line voltage of the generator (11) operating in the wind power unit (1) is 20V, the line voltage frequency is 14 Hz, and the single-stage three-phase AC-DC conversion of the present invention. The output voltage of the device is 400V _DC and the output waveform of the generator output phase voltage e _a and the output phase current i _a is 30W of full load output power.

The nineteenth figure is the single-stage three-phase AC-DC converter of the present invention, which has a line voltage of 20V and a line voltage frequency of 14 Hz outputted by the generator (11) operating in the wind power unit (1). The output waveforms of the output voltages of 400V _DC and the full-load output power of 30W are the analog waveforms of the phase currents i _a , i _b and i _c .

The twentieth figure is the single-stage three-phase AC-DC converter of the present invention, which has a line voltage of 20V and a line voltage frequency of 14 Hz outputted by the generator (11) operating in the wind power unit (1). The analog waveforms of the voltages V _c1 , V _{c2 ,} and V _c3 on the first capacitor, the second capacitor, and the third capacitor in the conversion circuit of the output voltage of 400V _DC and the full load output power of 30W.

The twenty-first figure is the single-stage three-phase AC-DC conversion of the present invention. The line voltage of the generator (11) operating in the wind power unit (1) is 20V, the line voltage frequency is 14 Hz. The analog waveform of the output voltage V _o and the output current I _o on the output load resistor (R) in the converter circuit with output voltage of 400V _DC and full load output power of 30W.

As described above, the implementation description and the drawings provided by the present invention are compared to the present invention. The preferred embodiment is not limited to the invention.

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.

(2) ‧‧‧Three-phase input voltage terminal

(3)‧‧‧Power factor correction circuit

(31)‧‧‧Filter circuit

(32)‧‧‧First inductance

(33)‧‧‧Three-phase bridge rectifier

(4)‧‧‧Transition circuit

Claims (3)

A single-stage three-phase AC-DC converter applied to a small-scale wind power generation system includes: a three-phase input voltage terminal; a power factor correction circuit electrically connected to the three-phase input voltage a conversion circuit, the conversion circuit is electrically connected to the power factor correction circuit, wherein the conversion circuit includes a switch, a first diode, a second diode, a third diode, and a a fourth diode, a first capacitor, a second capacitor, a third capacitor, a primary side inductor, a secondary side inductor, and an output load resistor, wherein the primary side inductance and the secondary side inductance are mutually Is coupled to the inductor, and the anode end of the first diode is connected to the anode end of the second diode, and the cathode end of the first diode is connected to the anode terminal and the primary inductor of the third diode One end of the switch and the other end of the switch, the other end of the primary side inductor is connected to the cathode end of the second diode and forms a first node, and the first node is connected to one end of the first capacitor and one end of the second capacitor. And the third diode The cathode end is connected to the other end of the second capacitor and the third capacitor end, and the cathode end of the third diode is connected to one end of the secondary side inductor, and the other end of the second side inductor is connected to the fourth pole An anode end of the body, wherein the other end of the third capacitor is connected to the cathode end of the fourth diode and connected to one end of the output load resistor, and the source terminal of the switch and the other end of the first capacitor and the output load The other ends of the resistors are connected to each other; The large current pulse generated by the three-phase input voltage terminal is reduced by the power factor correction circuit, and voltage conversion is performed via the conversion circuit. The single-stage three-phase AC-DC converter applied to a small-scale wind power generation system according to claim 1, wherein the power factor correction circuit comprises a filter circuit, three first inductors, and a three-phase bridge a rectifier, and one end of the filter circuit is electrically connected to the three-phase input voltage end, the other end of the filter circuit is electrically connected to the three first inductors, and the three first inductors are electrically connected to the three-phase bridge And a rectifier, and the three-phase bridge rectifier is electrically connected to the conversion circuit. The single-stage three-phase AC-DC converter applied to a small-scale wind power generation system according to claim 2, wherein the filter circuit comprises three filter inductors and three filter capacitors, and each of the filter inductors is connected in series Each of the filter capacitors.