TWM464962U - Self-oscillating and single stage high power factor led driver circuit - Google Patents

Abstract

The utility model is related to a self-oscillating and single stage high power factor driver circuit having a signal generator. The signal generator has a signal triggered circuit, a quasi-half-bridge resonant circuit, a storage circuit and a signal triggered transformer. Each one of the signal triggered circuit has a triggered switch and a signal triggered transformer. The storage circuit has a SDIAC, one end of a storage capacitor (C2) is electronically connected with the SDIAC and the SDIAC is activated by a voltage on the storage capacitor (C2). The efficiency can be improved by the self-driven switch of the circuit and the signal-triggered switch (S1,S2) inside the circuit works in a zero voltage switching state. The self-driven switch of the circuit can electrically connected with a LEC or an array of LED.

Description

Self-excited single-stage high power factor LED driving circuit

Light-emitting diode drive circuit, especially self-excited single-stage high power factor light-emitting diode driving circuit

The driving circuit is an intermediate circuit between the main circuit and the control circuit for amplifying the signal of the control circuit, wherein the driving circuit also has the function of isolating the load or adjusting the voltage and current of the input load. In the existing circuit architecture, for example, a conventional self-excited circuit, as shown in FIG. 11A, the advantage of the conventional self-excited circuit architecture is that the oscillation can be formed by the resonant tank in the circuit architecture, and the switch is driven. Turning on or off, thereby eliminating the manufacturing cost increased by using the integrated circuit, but the power factor of the power input by the conventional self-excited circuit architecture is low, and it is necessary to rely on the correcting circuit to improve the power, or only Used in electronic devices where power factor is not limited by national safety regulations. For another example, a single-stage high power factor circuit, as shown in FIG. 11B, can achieve power factor correction by switching between a capacitor LPFC and a quasi-half bridge resonant circuit in a circuit structure of a single-stage high power factor circuit. The effect, and the switching switches in the circuit are also operated at zero voltage switching, but in the single-stage high power factor circuit, in order to provide the trigger signal, there must be an additional integrated circuit to drive the conduction of the switch. And shutting down, thus increasing the manufacturing cost of the circuit architecture. It can be seen from the above examples that the current driving circuits have their own shortcomings and advantages, and cannot have an integrated circuit architecture to solve the above mentioned problems at the same time.

At present, the driving circuits have their own shortcomings and advantages. For example, if the power factor is too low or an integrated circuit is needed to drive the switching on and off, there is no integrated circuit architecture to solve the problem of the user. The invention provides a self-excited single-stage high power factor driving circuit, comprising a first rectifying circuit and a signal generating circuit, wherein the signal generating circuit comprises a first signal trigger circuit, a signal triggering circuit 2, and a quasi-half bridge resonance The first signal triggering circuit, the second signal triggering circuit, the quasi-half bridge resonant circuit, the energy storage circuit and the trigger signal transformer are all electrically connected, wherein: the circuit, the energy storage circuit and the trigger signal transformer The trigger signal transformer has three sets of contacts, each of the signal trigger circuits includes a trigger switch and the trigger signal transformer, and the first signal trigger circuit is electrically connected to the second contact connected to the trigger signal transformer, and the first a second signal trigger circuit and the third contact of the trigger signal transformer, wherein: the signal trigger circuit is included The trigger signal of the transformer are connected in parallel a set of zener diodes, which are parallel trigger switch bypass diodes, the tank circuit comprising a storage capacitor and a two-way trigger diode, wherein the storage capacitor (C ₂ ) one end is electrically connected to the bidirectional trigger diode, and the voltage of the storage capacitor (C ₂ ) is electrically connected to an input inductor and an input capacitor as an AC power source of the bidirectional trigger diode. The AC power supply The output AC power is input to the rectifier circuit via the input inductor and the input capacitor, and the DC pulse outputted by the rectifier circuit is input to the signal generating circuit via a power factor correction inductor.

The quasi-half bridge resonant circuit is connected in series with a high frequency balance transformer, and the high frequency isolation transformer is electrically connected to a second rectifying circuit. The second rectifying circuit is connected in parallel with an output capacitor and the output capacitor is connected in parallel with a light emitting diode.

Thereby, the present invention has the following advantages:

1. The power factor correction inductor (L _PFC ) 12 and the switching switch of the quasi-half bridge resonant circuit can achieve the power factor correction effect, and can also reduce the voltage to the voltage required by the load.

2. The self-driving switch can be driven by the circuit itself, and the trigger switches (S ₁ , S ₂ ) in the circuit are operated at zero voltage switching, which can improve the efficiency of use.

50‧‧‧AC power supply

11‧‧‧First rectifier circuit

12‧‧‧Power Correction Circuit (L _PFC )

20‧‧‧Signal generation circuit

21‧‧‧First signal trigger circuit

211‧‧‧ trigger switch

22‧‧‧second signal trigger circuit

23‧‧‧ quasi-half bridge resonant circuit

24‧‧‧ Energy storage circuit

25‧‧‧Trigger signal transformer

30‧‧‧Output circuit

31‧‧‧High frequency isolation transformer

32‧‧‧Second rectifier circuit

33‧‧‧Lighting diode

(L _IN )‧‧‧Input inductance

(C _IN )‧‧‧ Input Capacitor

(C ₁ , C ₂ ) ‧ ‧ storage capacitors

(C _O )‧‧‧output capacitor

(T _signal1 , T _signal2 T _signal3 ) _{‧‧‧Contacts of the} trigger signal transformer

(SIDAC)‧‧‧ Bidirectional Trigger Diode

(D _B )‧‧‧ Bypass diode

The first figure is an actual circuit diagram of a preferred embodiment of the present invention.

The second figure is a circuit action diagram I of the preferred embodiment of the present invention.

The third figure is a circuit action diagram II of a preferred embodiment of the present invention.

The fourth figure is a circuit diagram III of the circuit of the preferred embodiment of the present invention.

Figure 5 is a diagram showing the operation of the circuit of the preferred embodiment of the present invention.

FIG. 6A is a schematic diagram of high frequency switching of input voltage and inductor current according to a preferred embodiment of the present invention.

FIG. 6B is a waveform diagram of voltage and current in which the input voltage and the input current are not filtered by the preferred embodiment of the present invention.

The seventh figure is a waveform diagram of the input current flowing through the filtered voltage and current according to a preferred embodiment of the present invention.

Figure 8 is a diagram showing the input voltage of the inductor current I _LPFC , the storage capacitor voltage and the quasi-half bridge resonant circuit in accordance with a preferred embodiment of the present invention.

Figure 9 is a schematic diagram showing the resonant current after the resonance voltage is weak according to a preferred embodiment of the present invention.

FIG. 10 is a schematic diagram of zero voltage switching of the trigger switches S1 and S2 according to a preferred embodiment of the present invention.

Figure 11A is a prior art diagram of a preferred embodiment of the present invention.

Figure 11B is a prior art diagram of a preferred embodiment of the present invention.

The invention provides a self-excited single-stage high power factor LED driving circuit, comprising a first rectifying circuit 11, a signal generating circuit 20 and an output circuit 30.

Referring to the first figure, an AC power source 50 is electrically connected to an input inductor (L _IN ) and an input capacitor (C _IN ). The AC power output by the AC power source 50 is via the input inductor (L _IN ) and the input capacitor (C). _IN ) is input to the first rectifier circuit 11, and the first rectifier circuit 11 can be a full-wave rectifier circuit or a half-wave rectifier circuit, and the DC pulse outputted by the first rectifier circuit 11 passes through a power factor. The correction inductor (L _PFC ) 12 is input to the signal generating circuit 20. The signal generating circuit 20 includes a first signal trigger circuit 21, a second signal trigger circuit 22, a quasi-half bridge resonant circuit 23, a tank circuit 24 and a trigger signal transformer 25, and the first signal trigger circuit 21 The second signal triggering circuit 22, the quasi-half bridge resonant circuit 23, the energy storage circuit 24 and the trigger signal transformer 25 are electrically connected to each other, wherein the trigger signal transformer 25 has three sets of contacts (T _signal1 , T _{signal2 )} , T _signal3 ).

Each trigger circuit includes a trigger switch (S ₁ /S ₂ ) 211 and a corresponding contact of the trigger signal transformer 25 (T _signal2 /T _signal3 ), the first signal trigger circuit 21 and the trigger signal transformer 25 The second signal (T _{signal 2} ) is electrically connected, and the second signal trigger circuit 22 is electrically connected to the third contact (T _{signal 3} ) of the trigger signal transformer 25 , wherein the first signal trigger circuit 21 and The contact (T _signal2 /T _signal3 ) of the trigger signal transformer 25 included in the second signal trigger circuit 22 is respectively connected in parallel with a set of reversely connected _{synchronizing} diodes, and the trigger switch (S ₁ / S ₂ ) 211 is respectively connected in parallel with a bypass diode; in the present invention, the trigger switch (S ₁ /S ₂ ) 211 may be a metal oxide semiconductor (MOSFET) or a bipolar transistor (BJT), which is not provided herein. limit.

The quasi-half bridge resonant circuit 23 includes a resistor (R) and an inductor (L). The inductor and the capacitor are connected in series to each other to generate resonance, and the quasi-half bridge resonant circuit 23 and the first of the trigger signal transformer 25 The contacts (T _signal1 ) are connected in series.

The energy storage circuit 24 includes two storage capacitors (C ₁ , C ₂ ) and a bidirectional trigger diode (SIDAC), wherein one end of the storage capacitor (C ₂ ) is electrically connected to the bidirectional trigger diode (SIDAC). another end of the diac (SIDAC) of the third trigger signal contacts transformer _(T signal3) 25 of the other end is connected to the trigger point of the third order signal transformer _(T signal3) of the storage 25 of One end of the capacitor (C ₂ ) is connected, so that the storage capacitor (C ₂ ), the bidirectional trigger diode (SIDAC) and the third order point of the trigger signal transformer 25 (T _signal3 ) form a circuit loop. The junction of the storage capacitor (C ₂ ) and the bidirectional trigger diode (SIDAC) is connected to a resistor and an anode of a diode, and the other end of the resistor is connected to the storage capacitor (C ₁ ) to store the capacitor The other end of the energy capacitor (C ₁ ) is connected to the storage inductor (C ₂ ).

Please refer to the sixth and seventh figures. The power factor correction effect can be achieved by correcting the inductance (L _PFC ) 12 and the switching switch of the quasi-half bridge resonant circuit 23, as shown in FIG. 6A and B, the line segment 1 And the third and fourth segments are respectively the input inductor current (I _LPFC ) flowing through the input inductor (L _IN ) and the input voltage of the AC power source 50, if the input inductor current (I _LPFC ) is in a discontinuous conduction ( In the case of DCM), when the voltage across the input inductor (L _IN ) is increased, the input inductor current (I _LPFC ) is also increased accordingly, so that the input inductor current exhibits a 60 Hz waveform packet and then passes the high frequency filter. Complete the work of correcting the cause.

Referring to the second and third figures, the AC power outputted by the AC power source 50 is rectified by the rectifier circuit 11 and a DC pulse is outputted to the signal generating circuit 21, and the DC pulse is connected in parallel to the trigger switch (S ₁ ). After the bypass diode of 21, the two storage capacitors (C ₁ , C ₂ ) of the storage circuit 24 are charged and stored.

The two storage capacitors (C ₁ , C ₂ ) gradually increase in voltage across the two ends under continuous charging and energy storage, when the voltage across the storage capacitor (C ₂ ) is higher than the bidirectional trigger diode (SIDAC) ) the bidirectional trigger when the breakdown voltage of diodes (SIDAC) thus turned on after turning on the storage capacitor (C ₂₎ forming the start of discharge circuit of the two-way trigger diode (SIDAC) through, so that the trigger signal transformer _(T signal3) 25 is turned on and The trigger switch (S ₂ ) 211 is triggered to be turned on.

Please refer to the fourth and fifth figures. The power-repairing inductance (L _PFC ) 12 forms a charging circuit via the triggering switch (S ₂ ) 211. The function of the modified inductor current I _LPFC flows through the power-correcting inductance (L). _PFC ) 12 and the trigger switch (S ₂ ) 211, and the storage capacitor current (Ir) flowing through the storage capacitor (C ₁ ) forms a loop via the trigger switch (S ₂ ) 211 to the quasi-half bridge circuit 23 Charge it.

The quasi-half bridge resonant circuit 23 performs charging while _turning on the trigger signal transformer (T _signal1 ) 25 to turn on the trigger switch (S ₁ ) 211. Referring to the ninth and tenth views, the quasi-half bridge resonance is in the present invention. Circuit 23 can be designed to have an overall impedance that is inductive, while its inductive impedance allows the trigger switch (S ₁ , S ₂ ) 211 to operate in a zero voltage switching operating environment.

Referring to the eighth figure, after the trigger switch (S ₁ ) 211 is turned on, the power is corrected by the correction inductor current I _LPFC flowing through the power _factor correction inductor (L _PFC ) 12 and the trigger switch (S ₁ ) 211 and the power factor The correction inductor (L _PFC ) 12 is charged, and at the same time, the storage capacitor current (Ir) flowing through the storage capacitor (C ₁ ) forms a loop with the trigger switch (S ₁ ) 211 and the storage capacitor (C ₁ Charging is performed until the quasi-half bridge resonant circuit 23 performs oscillating commutation, and the trigger switch (S ₁ ) 211 is turned off, and the trigger switch (S ₂ ) 211 is turned on to repeat the above-described circuit operation.

The present invention can be connected in series with the quasi-half bridge resonant circuit 23 with a high frequency off-balance transformer 31. The high frequency isolation transformer 31 is electrically connected to a second rectifying circuit 32. The second rectifying circuit 32 is connected in parallel with an output capacitor (C _O The output capacitor (C _O ) is connected in parallel with a light-emitting diode 33. The light-emitting diode 33 can be a single or a plurality of LED arrays formed by the LEDs 33. The high frequency isolation transformer 31 transfer an AC voltage to the second rectifier circuit 32, the second rectifying circuit 32 rectifies the AC voltage of a DC voltage, the DC voltage after the output capacitor (C _O) of the filter is supplied The light emitting diode 33 is the DC power source.

Thereby, the present invention has the following advantages:

1. The power-correcting effect can be corrected by the power-correcting inductance (L _PFC ) 12 and the switching switch of the quasi-half bridge resonant circuit 23, and the voltage can be reduced to the voltage required by the load.

2. The self-driving switch can be driven by the circuit itself, and the trigger switches (S ₁ , S ₂ ) in the circuit are operated at zero voltage switching, which can improve the efficiency of use.

50‧‧‧AC power supply

11‧‧‧First rectifier circuit

12‧‧‧Power Correction Circuit (L _PFC )

20‧‧‧Signal generation circuit

21‧‧‧First signal trigger circuit

211‧‧‧ trigger switch

22‧‧‧second signal trigger circuit

23‧‧‧ quasi-half bridge resonant circuit

24‧‧‧ Energy storage circuit

25‧‧‧Trigger signal transformer

30‧‧‧Output circuit

31‧‧‧High frequency isolation transformer

32‧‧‧Second rectifier circuit

33‧‧‧Lighting diode

(L _IN )‧‧‧Input inductance

(C _IN )‧‧‧ Input Capacitor

(Co)‧‧‧ Output Capacitance

Claims (3)

A self-excited single-stage high-power-factor LED driving circuit includes a first rectifying circuit and a signal generating circuit, wherein: the signal generating circuit includes a first signal triggering circuit and a second signal triggering circuit. a quasi-half bridge resonant circuit, a tank circuit and a trigger signal transformer, the first signal trigger circuit, the second signal trigger circuit, the quasi-half bridge resonant circuit, the tank circuit and the trigger signal transformer are electrically connected The trigger signal transformer includes a first contact, a second contact, and a third contact; each of the signal trigger circuits includes a trigger switch and the trigger signal transformer, the first signal trigger circuit and the trigger signal transformer The second contact is electrically connected, and the second signal triggering circuit is connected to the third contact of the trigger signal transformer; the signal triggering circuit includes the trigger signal transformers and a set of the synchronizing diodes are connected in parallel. the trigger switch are connected in parallel bypass diodes; the tank circuit comprises a storage capacitor and a two-way trigger diode, wherein the storage capacitor (C ₂₎ of End and the diac electrically connected to a two-way trigger diode and the other end connected to one end of the third trigger signal contacts of the transformer, the other end of the third order signal to the trigger point of the transformer and the storage capacitor (C ₂ ) one end is connected, the connection point of the storage capacitor (C ₂ ) and the bidirectional trigger diode is connected to a resistor and an anode of a diode, and the other end of the resistor is connected to the storage capacitor (C ₁ ) The other end of the storage capacitor (C ₁ ) is connected to the storage inductor (C ₂ ), and the alternating current output by the alternating current power source is input to the rectifier circuit via the input inductor and the input capacitor, and the rectifier circuit outputs a DC pulse. The wave is input to the signal generating circuit via a power factor correction inductor. The self-excited single-stage high power factor LED driving circuit according to the first aspect of the application, wherein the quasi-half bridge resonant circuit comprises an inductor and a capacitor, and the inductor and the capacitor are connected in series with each other. The self-excited single-stage high-power factor LED driving circuit according to the second aspect of the application, wherein the quasi-half bridge resonant circuit is connected in series with a high-frequency balance transformer, the high-frequency isolating transformer and a second rectifying circuit Electrically connected, the second rectifier circuit is connected in parallel with an output capacitor and the output capacitor is connected in parallel with a light-emitting diode.