CN105141150B - Auto-excitation type BJT types are without bridge Cuk PFC rectification circuits - Google Patents

Abstract

A self-excited BJT type bridgeless Cuk PFC rectifier circuit, including input capacitor Ci, NPN type BJT tube Q1, NPN type BJT tube Q2, NPN type BJT tube Q3, NPN type BJT tube Q4, NPN type BJT tube Q5, NPN type Type BJT tube Q6, NPN type BJT tube Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8, inductor L1, inductor L2, inductor L3, capacitor Cs, output capacitor Co , resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7 and controlled current source group M1. The invention simplifies the structure of the driving circuit, has high driving efficiency, and simultaneously obtains the performance of easy self-starting.

Description

Self-excited BJT Bridgeless Cuk PFC Rectifier Circuit

technical field

The invention relates to a PFC rectifier circuit, which is applied to high-quality electric energy conversion occasions of AC input and DC output, such as: micro energy collection system, new energy power generation system, battery charging system, LED lighting system, etc., especially a bridgeless CukPFC rectifier circuit.

Background technique

PFC rectifier circuit is a circuit with power factor correction (PFC) function that can convert AC power into DC power, which can improve the utilization rate of DC load to AC power and reduce the pollution of current harmonics to AC bus or AC power grid. .

The traditional Cuk PFC rectifier circuit is a kind of PFC rectifier circuit, and its main circuit is generally composed of a bridge rectifier circuit cascaded with a Cuk circuit. In order to reduce the loss of the bridge rectifier circuit, a bridgeless Cuk PFC rectifier circuit came into being. The bridgeless CukPFC rectifier circuit mainly achieves the purpose of improving the circuit efficiency by reducing the number of conducting devices in the path.

In the early days, the BJT of Si material had disadvantages such as large driving loss, high switching loss, and large device dynamic impedance. Therefore, in order to obtain low power consumption, most of the fully controlled devices in the small and medium power bridgeless Cuk PFC rectifier circuit use MOSFETs. However, the MOSFET is a voltage-type driving device, and compared with the current-type driving device BJT, the driving circuit of the MOSFET is more complicated than that of the BJT. Especially in the working environment of ultra-low voltage or high voltage, the design of MOSFET driving circuit is quite difficult.

Contents of the invention

In order to overcome the deficiencies of the existing MOSFET type bridgeless Cuk PFC rectifier circuit, the MOSFET drive circuit is complicated, the drive efficiency is low, and the self-starting performance is poor, the present invention provides a simplified drive circuit structure, high drive efficiency, and easy self-starting at the same time. The self-excited BJT type bridgeless Cuk PFC rectifier circuit with the performance of starting.

The technical solution adopted by the present invention to solve its technical problems is:

A self-excited BJT type bridgeless Cuk PFC rectifier circuit, including input capacitor Ci, NPN type BJT tube Q1, NPN type BJT tube Q2, NPN type BJT tube Q3, NPN type BJT tube Q4, NPN type BJT tube Q5, NPN type Type BJT tube Q6, NPN type BJT tube Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8, inductor L1, inductor L2, inductor L3, capacitor Cs, output capacitor Co , resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7 and are used to control the base current of the NPN type BJT tube Q1 through port a so as to realize the control of the working state of the NPN type BJT tube Q1 and Control the base current of NPN BJT tube Q2 through port b to control the working state of NPN BJT tube Q2 and control the base current of NPN BJT tube Q5 through port c to realize the control of the working state of NPN BJT tube Q5 Controlled current source group M1, one end of the input capacitor Ci is connected to one end of the AC power supply vac, one end of the resistor R1, one end of the inductor L1 and the anode of the diode D7, and the other end of the inductor L1 is connected to the NPN type BJT tube Q1 at the same time The collector of the diode D1, the cathode of the diode D1, one end of the resistor R3 and the anode of the diode D3 are connected, the cathode of the diode D3 is connected with the collector of the NPN BJT transistor Q5, the cathode of the diode D4 and one end of the capacitor Cs, and the other end of the capacitor Cs One end is connected to the anode of diode D5 and the cathode of diode D6 at the same time, the anode of diode D6 is connected to one end of inductor L3, and the other end of inductor L3 is connected to one end of output capacitor Co, the positive end of output voltage Vo and one end of load Z1 , the other end of the load Z1 is simultaneously connected with the negative end of the output voltage Vo, the other end of the output capacitor Co, the cathode of the diode D5, the emitter of the NPN BJT tube Q5, the emitter of the NPN BJT tube Q6, and the NPN BJT tube Q7 The emitter of the resistor R5, one end of the resistor R6, the emitter of the NPN BJT tube Q1, the emitter of the NPN BJT tube Q2, the emitter of the NPN BJT tube Q3, the emitter of the NPN BJT tube Q4, The anode of the diode D1 is connected to the anode of the diode D2, and the base of the NPN BJT transistor Q1 is connected to the other end of the resistor R1, the collector of the NPN BJT transistor Q3, and the port a of the controlled current source group M1. The NPN BJT The base of the tube Q3 is connected to the other end of the resistor R3, the other end of the resistor R5 and the base of the NPN BJT tube Q6, and the collector of the NPN BJT tube Q6 is connected to one end of the resistor R7 and the controlled current source group M1 Port c of the NPN type BJT tube Q7 and the base of the NPN type BJT tube Q5 are connected, and the other end of the resistor R7 is connected to the cathode of the diode D7 and the cathode of the diode D8 at the same time. The other end of the input capacitor Ci is connected to the other end of the AC power supply vac, one end of the resistor R2, one end of the inductor L2 and the anode of the diode D8, and the other end of the inductor L2 is connected to the collector of the NPN type BJT transistor Q2, The cathode of the diode D2, one end of the resistor R4 and the anode of the diode D4 are connected, and the base of the NPN type BJT transistor Q2 is simultaneously connected with the other end of the resistor R2, the collector of the NPN type BJT transistor Q4 and the port b of the controlled current source group M1 The base of the NPN BJT transistor Q4 is simultaneously connected to the other end of the resistor R4, the other end of the resistor R6 and the base of the NPN BJT transistor Q7.

Further, both ends of the resistor R1 are connected in parallel with an accelerating capacitor C1, both ends of the resistor R2 are connected in parallel with an accelerating capacitor C2, both ends of the resistor R3 are connected in parallel with an accelerating capacitor C3, both ends of the resistor R4 are connected in parallel with an accelerating capacitor C4, and both ends of the resistor R7 are connected in parallel with an accelerating capacitor C5. This preferred solution can accelerate the dynamic characteristics of the self-excited BJT bridgeless Cuk PFC rectifier circuit.

Further, the controlled current source group M1 includes NPN type BJT tube Qa1, NPN type BJT tube Qa2, NPN type BJT tube Qa3, resistor Ra1, resistor Ra2, resistor Ra3, resistor Ra4, resistor Ra5, resistor Ra6, resistor Ra7 , resistor Ra8 and resistor Ra9, one end of resistor Ra3 is port a of controlled current source group M1, one end of resistor Ra6 is port b of controlled current source group M1, and one end of resistor Ra9 is port of controlled current source group M1 c. The other end of the resistor Ra3 is connected to the collector of the NPN BJT transistor Qa1, the base of the NPN BJT transistor Qa1 is connected to one end of the resistor Ra1 and one end of the resistor Ra2 at the same time, and the other end of the resistor Ra1 is connected to one end of the AC power supply vac The other end of the resistor Ra6 is connected to the collector of the NPN type BJT tube Qa2, the base of the NPN type BJT tube Qa2 is connected to one end of the resistor Ra4 and one end of the resistor Ra5 at the same time, and the other end of the resistor Ra4 is connected to the other end of the AC power supply vac One end is connected, the other end of the resistor Ra9 is connected to the collector of the NPN BJT transistor Qa3, the base of the NPN BJT transistor Qa3 is connected to one end of the resistor Ra7 and one end of the resistor Ra8 at the same time, and the other end of the resistor Ra7 is connected to the cathode of the diode D8 The emitter of NPN BJT tube Qa1 is connected with the emitter of NPN BJT tube Qa2, the emitter of NPN BJT tube Qa3, the other end of resistor Ra2, the other end of resistor Ra5, the other end of resistor Ra8 and the output voltage The negative end of Vo is connected. The self-excited BJT bridgeless Cuk PFC rectifier circuit has an input voltage feed-forward function.

Further, the controlled current source group M1 includes NPN type BJT tube Qb1, NPN type BJT tube Qb2, NPN type BJT tube Qb3, resistor Rb1, resistor Rb2, resistor Rb3, resistor Rb4, resistor Rb5, capacitor Cb1, resistor Rb1 One end of resistor Rb2 is port a of controlled current source group M1, one end of resistor Rb2 is port b of controlled current source group M1, one end of resistor Rb3 is port c of controlled current source group M1, and the other end of resistor Rb1 is connected to NPN The collector of the NPN BJT tube Qb1 is connected, the other end of the resistor Rb2 is connected to the collector of the NPN BJT tube Qb2, the other end of the resistor Rb3 is connected to the collector of the NPN BJT tube Qb3, and the base of the NPN BJT tube Qb1 is simultaneously It is connected with the base of NPN BJT tube Qb2, the base of NPN BJT tube Qb3, one end of capacitor Cb1, one end of resistor Rb4 and one end of resistor Rb5, and the other end of capacitor Cb1 is connected with the other end of resistor Rb5 and the output voltage The positive end of Vo, the emitter of the NPN BJT transistor Qb1, the emitter of the NPN BJT transistor Qb2, and the emitter of the NPN BJT transistor Qb3 are connected, and the other end of the resistor Rb4 is connected with the negative end of the output voltage Vo. The self-excited BJT bridgeless Cuk PFC rectifier circuit has an output voltage stabilizing function.

The technical idea of the present invention is: with the development of new semiconductor material devices, the BJT of new materials (such as SiC) has shown smaller drive loss, very low resistivity, faster switching speed, lower temperature Dependence, good short-circuit capability and no secondary breakdown and many other advantages. Using BJT of new material in small and medium power bridgeless Cuk PFC rectifier circuit can not only obtain low power consumption, but also simplify the driving circuit of fully controlled devices. The fully-controlled device in the bridgeless Cuk PFC rectifier circuit adopts BJT, which can realize simple circuit, high efficiency, easy self-starting and other performances at the same time by using the advantages of BJT working performance and self-excited circuit technology.

The beneficial effects of the present invention are mainly manifested in that the self-excited BJT bridgeless Cuk PFC rectifier circuit has the ability to convert AC power into DC power with high quality, and the absolute value of the output DC voltage can be greater than, less than or equal to the input AC voltage Amplitude, simple circuit, high drive efficiency, easy self-start, suitable for a variety of control methods.

Description of drawings

Fig. 1 is a schematic diagram of the basic circuit structure of the present invention.

Fig. 2 is a schematic diagram of the circuit structure of the accelerated dynamic characteristic of the present invention.

Fig. 3 is a circuit diagram of Embodiment 1 of the present invention.

Fig. 4 is a circuit diagram of Embodiment 2 of the present invention.

Fig. 5 is a simulation working waveform diagram of Embodiment 1 of the present invention.

Fig. 6 is a detailed diagram of the simulated working waveform of Embodiment 1 of the present invention.

Fig. 7 is a simulation working waveform diagram of Embodiment 2 of the present invention.

Fig. 8 is a detailed diagram of the simulated working waveform of Embodiment 2 of the present invention.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

Referring to Figures 1 and 2, a self-excited BJT bridgeless Cuk PFC rectifier circuit includes an input capacitor Ci, an NPN BJT tube Q1, an NPN BJT tube Q2, an NPN BJT tube Q3, an NPN BJT tube Q4, NPN type BJT tube Q5, NPN type BJT tube Q6, NPN type BJT tube Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8, inductor L1, inductor L2, inductor L3 , capacitor Cs, output capacitor Co, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7 and are used to control the base current of NPN type BJT tube Q1 through port a so as to realize the NPN type BJT Control the working state of tube Q1 and control the base current of NPN BJT tube Q2 through port b to control the working state of NPN BJT tube Q2 and control the base current of NPN BJT tube Q5 through port c to realize NPN Type BJT tube Q5 is a controlled current source group M1 for controlling the working state, one end of the input capacitor Ci is connected to one end of the AC power supply vac, one end of the resistor R1, one end of the inductor L1, and the anode of the diode D7, and the other end of the inductor L1 At the same time, it is connected to the collector of NPN BJT tube Q1, the cathode of diode D1, one end of resistor R3 and the anode of diode D3, and the cathode of diode D3 is connected to the collector of NPN BJT tube Q5, the cathode of diode D4 and the capacitor Cs. One end is connected, the other end of the capacitor Cs is connected to the anode of the diode D5 and the cathode of the diode D6 at the same time, the anode of the diode D6 is connected to one end of the inductor L3, and the other end of the inductor L3 is simultaneously connected to one end of the output capacitor Co and the positive voltage of the output voltage Vo terminal and one end of the load Z1, and the other end of the load Z1 is simultaneously connected to the negative end of the output voltage Vo, the other end of the output capacitor Co, the cathode of the diode D5, the emitter of the NPN BJT tube Q5, and the emitter of the NPN BJT tube Q6 pole, emitter of NPN type BJT tube Q7, one end of resistor R5, one end of resistor R6, emitter of NPN type BJT tube Q1, emitter of NPN type BJT tube Q2, emitter of NPN type BJT tube Q3, NPN type The emitter of the BJT tube Q4, the anode of the diode D1 and the anode of the diode D2 are connected, and the base of the NPN type BJT tube Q1 is connected with the other end of the resistor R1, the collector of the NPN type BJT tube Q3 and the controlled current source group M1. Port a is connected, the base of NPN BJT tube Q3 is connected with the other end of resistor R3, the other end of resistor R5 and the base of NPN BJT tube Q6 at the same time, and the collector of NPN BJT tube Q6 is connected with one end of resistor R7 at the same time , the port c of the controlled current source group M1, the collector of the NPN BJT transistor Q7 and the base of the NPN BJT transistor Q5 are connected, and the other end of the resistor R7 is connected to the cathode of the diode D7 at the same time The other end of the input capacitor Ci is connected to the other end of the AC power supply vac, one end of the resistor R2, one end of the inductor L2 and the anode of the diode D8, and the other end of the inductor L2 is connected to the NPN type BJT tube Q2 at the same time. The collector of the diode D2, the cathode of the diode D2, one end of the resistor R4 and the anode of the diode D4 are connected, and the base of the NPN type BJT transistor Q2 is connected with the other end of the resistor R2, the collector of the NPN type BJT transistor Q4 and the controlled current source group The port b of M1 is connected, and the base of the NPN BJT transistor Q4 is simultaneously connected with the other end of the resistor R4, the other end of the resistor R6 and the base of the NPN BJT transistor Q7.

Further, both ends of the resistor R1 are connected in parallel with an accelerating capacitor C1, both ends of the resistor R2 are connected in parallel with an accelerating capacitor C2, both ends of the resistor R3 are connected in parallel with an accelerating capacitor C3, both ends of the resistor R4 are connected in parallel with an accelerating capacitor C4, and both ends of the resistor R7 are connected in parallel with an accelerating capacitor C5. This preferred solution can accelerate the dynamic characteristics of the self-excited BJT bridgeless Cuk PFC rectifier circuit.

Embodiment 1: Referring to Fig. 1, Fig. 3, Fig. 5 and Fig. 6, Embodiment 1 of the present invention has an input voltage feedforward function, which consists of an input capacitor Ci, an NPN type BJT transistor Q1, an NPN type BJT transistor Q2, and an NPN type BJT Tube Q3, NPN type BJT tube Q4, NPN type BJT tube Q5, NPN type BJT tube Q6, NPN type BJT tube Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8 , inductor L1, inductor L2, inductor L3, capacitor Cs, output capacitor Co, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, controlled current source group M1. Among them, the controlled current source M1 is composed of NPN type BJT tube Qa1, NPN type BJT tube Qa2, NPN type BJT tube Qa3, resistor Ra1, resistor Ra2, resistor Ra3, resistor Ra4, resistor Ra5, resistor Ra6, resistor Ra7, resistor Ra8 , Composed of resistor Ra9.

As shown in Figure 3, one end of the input capacitor Ci is simultaneously connected to one end of the AC power supply vac, one end of the resistor R1, one end of the inductor L1, and the anode of the diode D7, and the other end of the inductor L1 is simultaneously connected to the collector of the NPN type BJT transistor Q1 , the cathode of diode D1, one end of resistor R3 and the anode of diode D3 are connected, the cathode of diode D3 is connected with the collector of NPN BJT transistor Q5, the cathode of diode D4 and one end of capacitor Cs at the same time, and the other end of capacitor Cs is connected with The anode of the diode D5 is connected to the cathode of the diode D6, the anode of the diode D6 is connected to one end of the inductor L3, and the other end of the inductor L3 is simultaneously connected to one end of the output capacitor Co, the positive end of the output voltage Vo, and one end of the load Z1, and the load Z1 The other end of the output voltage Vo, the other end of the output capacitor Co, the cathode of the diode D5, the emitter of the NPN BJT tube Q5, the emitter of the NPN BJT tube Q6, and the emitter of the NPN BJT tube Q7 , one end of the resistor R5, one end of the resistor R6, the emitter of the NPN BJT tube Q1, the emitter of the NPN BJT tube Q2, the emitter of the NPN BJT tube Q3, the emitter of the NPN BJT tube Q4, and the diode D1 The anode is connected to the anode of the diode D2, the base of the NPN BJT tube Q1 is connected to the other end of the resistor R1, the collector of the NPN BJT tube Q3, and the port a of the controlled current source group M1, and the NPN BJT tube Q3 The base is simultaneously connected to the other end of the resistor R3, the other end of the resistor R5, and the base of the NPN BJT transistor Q6, and the collector of the NPN BJT transistor Q6 is simultaneously connected to one end of the resistor R7 and the port c of the controlled current source group M1. , the collector of the NPN BJT tube Q7 and the base of the NPN BJT tube Q5 are connected, the other end of the resistor R7 is connected to the cathode of the diode D7 and the cathode of the diode D8 at the same time, and the other end of the input capacitor Ci is connected to the AC power supply vac at the same time The other end, one end of the resistor R2, one end of the inductor L2, and the anode of the diode D8 are connected, and the other end of the inductor L2 is connected to the collector of the NPN BJT transistor Q2, the cathode of the diode D2, one end of the resistor R4, and the anode of the diode D4. , the base of the NPN BJT tube Q2 is connected to the other end of the resistor R2, the collector of the NPN BJT tube Q4, and the port b of the controlled current source group M1, and the base of the NPN BJT tube Q4 is connected to the terminal of the resistor R4 at the same time. The other end, the other end of the resistor R6 and the base of the NPN type BJT tube Q7 are connected, one end of the resistor Ra3 is the port a of the controlled current source group M1, one end of the resistor Ra6 is the port b of the controlled current source group M1, and the resistor One end of Ra9 is the port c of the controlled current source group M1, the other end of the resistor Ra3 is connected to the collector of the NPN type BJT transistor Qa1, and the base of the NPN type BJT transistor Qa1 is connected to one end of the resistor Ra1 and one end of the resistor Ra2 at the same time , the other end of the resistor Ra1 and One end of the AC power supply vac is connected, the other end of the resistor Ra6 is connected to the collector of the NPN type BJT transistor Qa2, the base of the NPN type BJT transistor Qa2 is connected to one end of the resistor Ra4 and one end of the resistor Ra5, and the other end of the resistor Ra4 is connected to the The other end of the AC power supply vac is connected, the other end of the resistor Ra9 is connected to the collector of the NPN BJT transistor Qa3, the base of the NPN BJT transistor Qa3 is connected to one end of the resistor Ra7 and one end of the resistor Ra8, and the other end of the resistor Ra7 Connected with the cathode of diode D8, the emitter of NPN BJT tube Qa1 is simultaneously connected with the emitter of NPN BJT tube Qa2, the emitter of NPN BJT tube Qa3, the other end of resistor Ra2, the other end of resistor Ra5, and the other end of resistor Ra8 The other end is connected to the negative end of the output voltage Vo.

Fig. 5 is the simulated working waveform figure of embodiment 1 of the present invention, and Fig. 6 is the detailed figure of simulated working waveform of embodiment 1 of the present invention, and its steady-state operating principle is as follows:

When vac>0, the AC power supply vac is in the positive half cycle (ie ta1<t<ta2); when vac<0, the AC power supply vac is in the negative half cycle (ie ta2<t<ta3). D2 and D7 are turned on in the positive half cycle of the AC power supply vac and cut off in the negative half cycle, and D1 and D8 are turned off in the positive half cycle of the AC power supply vac and turned on in the negative half cycle of the AC power supply vac.

(1) During the positive half cycle of the AC power supply vac, Q2 and D4 are cut off, and Q1 and Q5 are self-excited

When Q1 and Q5 are turned on (ie ta11<t<ta12), vac, L1, Q1, D2, L2 form the first loop, vac, L1, D3, Q5, D2, L2 form the second loop, Cs, Q5, Co, Z1, L3, and D6 form the third circuit, L1, L2, and L3 are all magnetized, the current iL1 of the inductor L1, the collector current iQc1 of Q1, the collector current iQc5 of Q5, and the current iL3 of the inductor L3 are all Increase. With the increase of iQc1, the working state of Q1 gradually shifts from the saturation region to the amplification region and the cut-off region under the action of Q3 and the port a of the controlled current source group M1. At the same time, under the action of Q6 and the port c of the controlled current source group M1, the working state of Q5 gradually shifts from the saturation region to the amplification region and cut-off region. At the moment when Q1 just enters the off state from the on state, assuming that L1=L2 and the collector current iQc1 of Q1>>the current iD3 of D3, if but like but

Among them, VBE_Qa1 is the base-emitter turn-on voltage drop of Qa1, β_Qa1 is the common-emitter current gain of Qa1, and β_Q1 is the common-emitter current gain of Q1. When Q1 and Q5 are cut off (ie ta12<t<ta13), vac, L1, D3, Cs, D5, D2, L2 form a loop, L3, D6, D5, Co, Z1 form another loop, L1, L2, Both L3 are magnetized, and the current iL1 of the inductor L1, the current iL3 of the inductor L3, and the current iD5 of the diode D5 all decrease. When iD5 decreases to zero, D5 ends, Q1 and Q5 are turned on again, and the cycle repeats.

(2) During the negative half cycle of the AC power supply vac, Q1 and D3 are cut off, and Q2 and Q5 are self-excited

Similarly, when Q2 and Q5 are turned on, vac, L2, Q2, D1, L1 form the first loop, vac, L2, D4, Q5, D1, L1 form the second loop, Cs, Q5, Co, Z1 , L3, and D6 constitute the third circuit, L1 and L2 are reversely magnetized, L3 is magnetized, the current iL1 of the inductor L1 increases in the opposite direction, the collector current iQc2 of Q2, the collector current iQc5 of Q5, and the current iL3 of the inductor L3 both increased. With the increase of iQc2, under the action of Q4 and the port b of the controlled current source group M1, the working state of Q2 gradually shifts from the saturation region to the amplification region and cut-off region. At the same time, under the action of Q7 and the port c of the controlled current source group M1, the working state of Q5 gradually shifts from the saturation region to the amplification region and cut-off region. At the moment when Q2 just enters the off state from the on state, assuming that L1=L2 and the collector current iQc2 of Q2>>the current iD4 of D4, if but like but

Among them, VBE_Qa2 is the base-emitter conduction voltage drop of Qa2, β_Qa2 is the common-emitter current gain of Qa2, and β_Q2 is the common-emitter current gain of Q2. When Q2 and Q5 are cut off, vac, L2, D4, Cs, D5, D1, L1 form a loop, L3, D6, D5, Co, Z1 form another loop, L1 and L2 reverse magnetization, L3 magnetization, The current iL1 of the inductor L1 decreases in reverse, and the current iL3 of the inductor L3 and the current iD5 of the diode D5 both decrease. When iD5 decreases to zero, D5 ends, Q2 and Q5 are turned on again, and the cycle repeats.

It can be known from the above that the peak current of the inductor L1 in Embodiment 1 of the present invention is related to the input AC voltage.

Embodiment 2: With reference to Fig. 1, Fig. 4, Fig. 7 and Fig. 8, Embodiment 2 of the present invention has output voltage stabilizing function, and it is composed of input capacitor Ci, NPN type BJT tube Q1, NPN type BJT tube Q2, NPN type BJT tube Q3, NPN type BJT tube Q4, NPN type BJT tube Q5, NPN type BJT tube Q6, NPN type BJT tube Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8, Inductor L1, inductor L2, inductor L3, capacitor Cs, output capacitor Co, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, controlled current source group M1. Among them, the controlled current source group M1 is composed of NPN BJT tube Qb1, NPN BJT tube Qb2, NPN BJT tube Qb3, resistor Rb1, resistor Rb2, resistor Rb3, resistor Rb4, resistor Rb5, and capacitor Cb1.

As shown in Figure 4, one end of the input capacitor Ci is simultaneously connected to one end of the AC power supply vac, one end of the resistor R1, one end of the inductor L1, and the anode of the diode D7, and the other end of the inductor L1 is simultaneously connected to the collector of the NPN type BJT transistor Q1 , the cathode of diode D1, one end of resistor R3 and the anode of diode D3 are connected, the cathode of diode D3 is connected with the collector of NPN BJT transistor Q5, the cathode of diode D4 and one end of capacitor Cs at the same time, and the other end of capacitor Cs is connected with The anode of the diode D5 is connected to the cathode of the diode D6, the anode of the diode D6 is connected to one end of the inductor L3, and the other end of the inductor L3 is simultaneously connected to one end of the output capacitor Co, the positive end of the output voltage Vo, and one end of the load Z1, and the load Z1 The other end of the output voltage Vo, the other end of the output capacitor Co, the cathode of the diode D5, the emitter of the NPN BJT tube Q5, the emitter of the NPN BJT tube Q6, and the emitter of the NPN BJT tube Q7 , one end of the resistor R5, one end of the resistor R6, the emitter of the NPN BJT tube Q1, the emitter of the NPN BJT tube Q2, the emitter of the NPN BJT tube Q3, the emitter of the NPN BJT tube Q4, and the diode D1 The anode is connected to the anode of the diode D2, the base of the NPN BJT tube Q1 is connected to the other end of the resistor R1, the collector of the NPN BJT tube Q3, and the port a of the controlled current source group M1, and the NPN BJT tube Q3 The base is simultaneously connected to the other end of the resistor R3, the other end of the resistor R5, and the base of the NPN BJT transistor Q6, and the collector of the NPN BJT transistor Q6 is simultaneously connected to one end of the resistor R7 and the port c of the controlled current source group M1. , the collector of the NPN BJT tube Q7 and the base of the NPN BJT tube Q5 are connected, the other end of the resistor R7 is connected to the cathode of the diode D7 and the cathode of the diode D8 at the same time, and the other end of the input capacitor Ci is connected to the AC power supply vac at the same time The other end, one end of the resistor R2, one end of the inductor L2, and the anode of the diode D8 are connected, and the other end of the inductor L2 is connected to the collector of the NPN BJT transistor Q2, the cathode of the diode D2, one end of the resistor R4, and the anode of the diode D4. , the base of the NPN BJT tube Q2 is connected to the other end of the resistor R2, the collector of the NPN BJT tube Q4, and the port b of the controlled current source group M1, and the base of the NPN BJT tube Q4 is connected to the terminal of the resistor R4 at the same time. The other end, the other end of the resistor R6 and the base of the NPN type BJT tube Q7 are connected, one end of the resistor Rb1 is the port a of the controlled current source group M1, one end of the resistor Rb2 is the port b of the controlled current source group M1, and the resistor One end of Rb3 is the port c of the controlled current source group M1, the other end of the resistor Rb1 is connected to the collector of the NPN type BJT tube Qb1, the other end of the resistor Rb2 is connected to the collector of the NPN type BJT tube Qb2, and the other end of the resistor Rb3 is connected to the collector of the NPN type BJT tube Qb2. One end and NPN type BJT tube Qb 3, the base of the NPN BJT tube Qb1 is connected to the base of the NPN BJT tube Qb2, the base of the NPN BJT tube Qb3, one end of the capacitor Cb1, one end of the resistor Rb4, and one end of the resistor Rb5. The other end of the capacitor Cb1 is connected to the other end of the resistor Rb5, the positive end of the output voltage Vo, the emitter of the NPN BJT transistor Qb1, the emitter of the NPN BJT transistor Qb2, and the emitter of the NPN BJT transistor Qb3. The resistor Rb4 The other end of is connected to the negative end of the output voltage Vo.

Fig. 7 is the simulation work wave form figure of embodiment 2 of the present invention, and Fig. 8 is the simulation work wave form detail figure of embodiment 2 of the present invention, and its steady-state working principle is as follows:

When vac>0, the AC power supply vac is in the positive half cycle (ie tb1<t<tb2); when vac<0, the AC power supply vac is in the negative half cycle (ie tb2<t<tb3). D2 and D7 are turned on in the positive half cycle of the AC power supply vac and cut off in the negative half cycle, and D1 and D8 are turned off in the positive half cycle of the AC power supply vac and turned on in the negative half cycle of the AC power supply vac.

(1) During the negative half cycle of the AC power supply vac, Q1 and D3 are cut off, and Q2 and Q5 are self-excited

When Q2 and Q5 are turned on (ie tb21<t<tb22), vac, L2, Q2, D1, L1 form the first loop, vac, L2, D4, Q5, D1, L1 form the second loop, Cs, Q5, Co, Z1, L3, and D6 constitute the third loop, L1 and L2 are magnetized in reverse, L3 is magnetized, the current iL1 of the inductor L1 increases in reverse, the collector current iQc2 of Q2, the collector current iQc5 of Q5, The current iL3 of the inductor L3 increases. With the increase of iQc2, under the action of Q4 and the port b of the controlled current source group M1, the working state of Q2 gradually shifts from the saturation region to the amplification region and cut-off region. At the same time, under the action of Q7 and the port c of the controlled current source group M1, the working state of Q5 gradually shifts from the saturation region to the amplification region and cut-off region. When Q2 and Q5 are cut off (ie tb22<t<tb23), vac, L2, D4, Cs, D5, D1, L1 form a loop, L3, D6, D5, Co, Z1 form another loop, L1 and L2 reverse In the direction of demagnetization, L3 demagnetizes, the current iL1 of the inductor L1 decreases in the opposite direction, and the current iL3 of the inductor L3 and the current iD5 of the diode D5 both decrease. When iD5 decreases to zero, D5 ends, Q2 and Q5 are turned on again, and the cycle repeats.

VBE_Qb is the base-emitter turn-on voltage drop of Qb2, Qb3, Qb1. when When , the controlled current source group M1 reduces the base currents of Q2 and Q5 through port b and port c, shortens the on-time of Q2 and Q5, and even prolongs the off-time of Q2 and Q5, so that Vo falls back. when When , the controlled current source group M1 maximizes the base currents of Q2 and Q5 through port b and port c, and maximizes the conduction time of Q2 and Q5, so that Vo picks up.

(2) During the positive half cycle of the AC power supply vac, Q2 and D4 are cut off, and Q1 and Q5 are self-excited

Similarly, when Q1 and Q5 are turned on, vac, L1, Q1, D2, and L2 form the first loop, vac, L1, D3, Q5, D2, and L2 form the second loop, and Cs, Q5, Co, and Z1 , L3, and D6 constitute the third circuit, L1, L2, and L3 are all magnetized, the current iL1 of the inductor L1, the collector current iQc1 of Q1, the collector current iQc5 of Q5, and the current iL3 of the inductor L3 all increase. With the increase of iQc1, the working state of Q1 gradually shifts from the saturation region to the amplification region and the cut-off region under the action of Q3 and the port a of the controlled current source group M1. When Q1 and Q5 are cut off, vac, L1, D3, Cs, D5, D2, and L2 form a loop, L3, D6, D5, Co, and Z1 form another loop, and L1, L2, and L3 all discharge magnetism, and the inductance of L1 The current iL1, the current iL3 of the inductor L3, and the current iD5 of the diode D5 all decrease. When iD5 decreases to zero, D5 ends, Q1 and Q5 are turned on again, and the cycle repeats.

VBE_Qb is the base-emitter turn-on voltage drop of Qb1, Qb2, Qb3. when , the controlled current source group M1 reduces the base currents of Q1 and Q5 through port a and port c, shortens the turn-on time of Q1 and Q5, and even prolongs the turn-off time of Q1 and Q5, so that Vo falls back. when When , the controlled current source group M1 maximizes the base currents of Q1 and Q5 through port a and port c, and maximizes the conduction time of Q1 and Q5, so that Vo picks up.

It can be known from the above that the output voltage Vo of Embodiment 2 of the present invention can be stabilized under the regulation of the controlled current source group M1. Especially under the condition of light load, under the action of the controlled current source group M1, Embodiment 2 of the present invention will work intermittently.

The content described in the embodiments of this specification is only an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms stated in the embodiments. The protection scope of the present invention also extends to the field Equivalent technical means that the skilled person can think of based on the concept of the present invention.

Claims (4)

1. a kind of auto-excitation type BJT types are without bridge Cuk PFC rectification circuits, it is characterised in that：Including input capacitance Ci, NPN type BJT pipe Q1, NPN type BJT pipes Q2, NPN type BJT pipes Q3, NPN type BJT pipes Q4, NPN type BJT pipes Q5, NPN type BJT pipes Q6, NPN type BJT Pipe Q7, diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, diode D8, Inductance L1, inductance L2, inductance L3, electric capacity Cs, output capacitance Co, resistance R1, resistance R2, resistance R3, resistance R4, resistance R5, electricity Hinder R6, resistance R7 and for controlling the base current of NPN type BJT pipes Q1 by port a so as to realize to NPN type BJT pipe Q1 works Make the control of state and the base current of NPN type BJT pipes Q2 is controlled so as to realize working NPN type BJT pipes Q2 by port b The control of state and the base current of NPN type BJT pipes Q5 is controlled so as to realize the shape that works NPN type BJT pipes Q5 by port c One end of controlled current source the group M1, input capacitance Ci of the control of state one end, of resistance R1 simultaneously with AC power vac End, the anode of one end of inductance L1 and diode D7 are connected, the other end of inductance L1 current collection simultaneously with NPN type BJT pipes Q1 The anode of pole, the negative electrode of diode D1, one end of resistance R3 and diode D3 is connected, and the negative electrode of diode D3 is while and NPN One end of the colelctor electrode, the negative electrode of diode D4 and electric capacity Cs of type BJT pipes Q5 is connected, the other end of electric capacity Cs simultaneously with two poles The anode of pipe D5 and the negative electrode of diode D6 are connected, and the anode of diode D6 is connected with one end of inductance L3, and inductance L3's is another One end of one end one end, the anode of output voltage Vo and load Z1 simultaneously with output capacitance Co is connected, and load Z1's is another End negative terminal, the other end of output capacitance Co, the negative electrode of diode D5, the transmitting of NPN type BJT pipes Q5 simultaneously with output voltage Vo Pole, the emitter stage of NPN type BJT pipes Q6, emitter stage, one end of resistance R5, one end of resistance R6, the NPN type of NPN type BJT pipes Q7 The emitter stage of BJT pipes Q1, the emitter stage of NPN type BJT pipes Q2, the emitter stage of NPN type BJT pipes Q3, the transmitting of NPN type BJT pipes Q4 The anode of pole, the anode of diode D1 and diode D2 is connected, and the base stage of NPN type BJT pipes Q1 is simultaneously another with resistance R1 End, the port a of the colelctor electrode of NPN type BJT pipes Q3 and controlled current source group M1 are connected, the base stage of NPN type BJT pipes Q3 simultaneously with The base stage of the other end, the other end of resistance R5 and NPN type BJT pipes Q6 of resistance R3 is connected, the colelctor electrode of NPN type BJT pipes Q6 While one end, the port c of controlled current source group M1, the colelctor electrode of NPN type BJT pipes Q7 and NPN type BJT pipes Q5 with resistance R7 Base stage be connected, the other end of resistance R7 is connected with the negative electrode of diode D7 and the negative electrode of diode D8 simultaneously, input capacitance The other end of Ci is while the sun of the other end, one end of resistance R2, one end of inductance L2 and diode D8 with AC power vac Extremely be connected, the other end of inductance L2 colelctor electrode simultaneously with NPN type BJT pipes Q2, the negative electrode of diode D2, resistance R4 one end with And the anode of diode D4 is connected, the base stage of NPN type BJT pipes Q2 is while the collection of the other end, NPN type BJT pipes Q4 with resistance R2 The port b of electrode and controlled current source group M1 is connected, the base stage of the NPN type BJT pipes Q4 other end, resistance simultaneously with resistance R4 The other end of R6 and the base stage of NPN type BJT pipes Q7 are connected.

2. auto-excitation type BJT types as claimed in claim 1 are without bridge Cuk PFC rectification circuits, it is characterised in that：Resistance R1 two ends are simultaneously Connection speed-up capacitor C1, resistance R2 two ends parallel connection speed-up capacitor C2, resistance R3 two ends parallel connection speed-up capacitor C3, resistance R4 two ends are in parallel Speed-up capacitor C4, resistance R7 two ends speed-up capacitor C5 in parallel.

3. auto-excitation type BJT types as claimed in claim 1 or 2 are without bridge Cuk PFC rectification circuits, it is characterised in that：It is described controlled Current source group M1 includes NPN type BJT pipes Qa1, NPN type BJT pipes Qa2, NPN type BJT pipes Qa3, resistance Ra1, resistance Ra2, resistance Ra3, resistance Ra4, resistance Ra5, resistance Ra6, resistance Ra7, resistance Ra8 and resistance Ra9, one end of resistance Ra3 is controlled current flow One end of the port a of source group M1, resistance Ra6 are the port b of controlled current source group M1, and one end of resistance Ra9 is controlled current source The port c of group M1, the other end of resistance Ra3 is connected with the colelctor electrode of NPN type BJT pipes Qa1, and the base stage of NPN type BJT pipes Qa1 is same When be connected with one end of resistance Ra1 and one end of resistance Ra2, the other end of resistance Ra1 and one end phase of AC power vac Even, the other end of resistance Ra6 is connected with the colelctor electrode of NPN type BJT pipes Qa2, and the base stage of NPN type BJT pipes Qa2 is while and resistance One end of Ra4 and one end of resistance Ra5 are connected, and the other end of resistance Ra4 is connected with the other end of AC power vac, resistance The other end of Ra9 is connected with the colelctor electrode of NPN type BJT pipes Qa3, the base stage of NPN type BJT pipes Qa3 one end simultaneously with resistance Ra7 And one end of resistance Ra8 is connected, the other end of resistance Ra7 is connected with the negative electrode of diode D8, the transmitting of NPN type BJT pipes Qa1 Pole simultaneously with the emitter stage of NPN type BJT pipes Qa2, the emitter stage of NPN type BJT pipes Qa3, the other end of resistance Ra2, resistance Ra5 The negative terminal of the other end, the other end of resistance Ra8 and output voltage Vo is connected.

4. auto-excitation type BJT types as claimed in claim 1 or 2 are without bridge Cuk PFC rectification circuits, it is characterised in that：It is described controlled Current source group M1 includes NPN type BJT pipes Qb1, NPN type BJT pipes Qb2, NPN type BJT pipes Qb3, resistance Rb1, resistance Rb2, resistance Rb3, resistance Rb4, resistance Rb5 and electric capacity Cb1, one end of resistance Rb1 is the port a of controlled current source group M1, the one of resistance Rb2 It is the port b of controlled current source group M1 to hold, and one end of resistance Rb3 is the port c of controlled current source group M1, and resistance Rb1's is another End is connected with the colelctor electrode of NPN type BJT pipes Qb1, and the other end of resistance Rb2 is connected with the colelctor electrode of NPN type BJT pipes Qb2, resistance The other end of Rb3 is connected with the colelctor electrode of NPN type BJT pipes Qb3, the base stage of NPN type BJT pipes Qb1 simultaneously with NPN type BJT pipes Qb2 Base stage, the base stage of NPN type BJT pipes Qb3, one end of electric capacity Cb1, one end of one end of resistance Rb4 and resistance Rb5 be connected, The other end of the electric capacity Cb1 other end simultaneously with resistance Rb5, the anode of output voltage Vo, the emitter stage of NPN type BJT pipes Qb1, The emitter stage of NPN type BJT pipes Qb2 and the emitter stage of NPN type BJT pipes Qb3 are connected, the other end and output voltage of resistance Rb4 The negative terminal of Vo is connected.