TW201414149A - High voltage ratio interleaved converter with soft-switching - Google Patents

Abstract

A high voltage ratio interleaved converter with soft-switching includes a soft-switching circuit and an interleaving circuit. The interleaving circuit includes a first step-up circuit and a second step-up circuit. The soft-switching circuit includes a first auxiliary circuit and a second auxiliary circuit. The first auxiliary circuit is electrically connected to the first step-up circuit. The first auxiliary circuit includes a first resonant capacitor, a first resonant inductor, a first auxiliary switch, and a first auxiliary diode. The second auxiliary circuit is electrically connected to the second step-up circuit. The second auxiliary circuit includes a second resonant capacitor, a second resonant inductor, a second auxiliary switch, and a second auxiliary diode. There may be a signal circuit included as well in the high voltage ratio interleaved converter with soft-switching, to control switches to achieve soft switching.

Description

Interleaved high step-up ratio soft-switching converter

This invention relates to an interleaved high step-up ratio converter and, more particularly, to an interleaved high step-up ratio soft-switching converter.

In recent years, due to the global energy crisis and environmental awareness, finding alternative energy has become an important issue. Many alternative energy sources such as solar energy, wind energy, hydropower, biomass and fuel cells are quite potential green energy sources. Among them, the fuel cell is a clean and pollution-free energy source, such as the proton exchange membrane fuel cell, which is often used, but due to its activation loss, ohmic polarization and concentration loss, the output voltage decreases with the load, which causes the output voltage to drop. As the output power of the fuel cell increases with loading, the output voltage gradually decreases, and the output current gradually rises, which is a device of low voltage and high current output. Other green energy sources also have lower output voltage characteristics, which limits the range of back-end applications.

Therefore, the conventional interleaved high step-up ratio converter has been developed to boost the low voltage output from the energy source to a high voltage and then to the DC link for a wider range of back end applications. However, most of the interleaved high-boost ratio converters are hard-switched, resulting in large switching and diode switching losses, low circuit efficiency, and loss of power accumulated in the switches and diodes, which is prone to heat.

A few attempts to use a soft-switching interleaved high step-up ratio converter can improve the switching loss problem, but it is complicated to achieve soft switching characteristics. The circuit makes the cost high and the implementation is not easy.

Therefore, the present invention provides an interleaved high step-up ratio soft-switching converter having a simple structure, comprising a soft switching circuit electrically connected to an interleaving boosting circuit. The interleaved boosting circuit includes at least a first boosting circuit and a second boosting circuit, and the second boosting circuit is electrically connected to the first boosting circuit; and the soft switching circuit corresponding to the interleaved boosting circuit includes at least one An auxiliary circuit is electrically connected to the first boosting circuit, and a second auxiliary circuit is electrically connected to the second boosting circuit, and the first auxiliary circuit and the second auxiliary circuit are also electrically connected; the first auxiliary circuit includes a first a resonant capacitor is electrically connected to the first boosting circuit, a first resonant inductor is electrically connected to the first boosting circuit and the first resonant capacitor, and a first auxiliary switch is electrically connected to the first resonant inductor The first auxiliary diode is electrically connected to the first boosting diode, and the first auxiliary diode is electrically connected to the first resonant inductor and the first auxiliary switch; the second auxiliary circuit includes a second resonant capacitor and a second boosting circuit. An electrical connection, a second resonant inductor is electrically connected to the second boosting circuit and the second resonant capacitor, and a second auxiliary switch is electrically connected to the second boosting circuit by being electrically connected to the second resonant inductor Sex connection, and a second secondary diode and a second resonant And the second auxiliary switch is electrically connected.

According to an embodiment of the present invention, the first boosting circuit includes a first energy storage inductor electrically connected to the second boosting circuit, and a first main switch electrically connected to the first energy storage inductor; and a second The boosting circuit includes a second energy storage inductor electrically connected to the first boosting circuit, and a second main switch electrically connected to the second energy storage inductor. The interleaved boost circuit can further include a first main two The pole body is electrically connected to the first boosting circuit, the second main diode is electrically connected to the second boosting circuit and the first main diode, the clamping capacitor and the first main diode and the second The main diode is electrically connected, and a load group is electrically connected to the second main diode; the load group includes an output capacitor electrically connected to the second main diode, and an output resistor and the output capacitor are electrically connected connection.

According to an embodiment of the present invention, the interleaved high step-up ratio soft-switching converter may further include a signal circuit electrically connected to the interleaved boosting circuit. The signal circuit comprises an original signal device, a first trigger, a first gate, a second trigger and a second gate. The original signal device includes an original signal end to generate an original signal, and a phase shift end generates a phase shift signal of the original signal; the first flip-flop is electrically connected to the original signal end, and the first flip-flop has a first output. And a first inverting end, the first output end can output a first auxiliary signal; the first and the second gate are electrically connected to the first inverting end and the original signal end, and the first gate has a second output end Outputting a first main signal; the second flip-flop is electrically connected to the phase shifting end, the second flip-flop has a third output end and a second inverting end, and the third output end can output a second auxiliary signal; The gate is electrically connected to the second inverting terminal and the phase shifting end, and the second gate has a fourth output terminal for outputting a second main signal. The first output terminal, the second output terminal, the third output terminal, and the fourth output terminal are electrically connected to the first auxiliary switch, the first main switch, the second auxiliary switch, and the second main switch, respectively. The phase shift signal can be a phase shift of 180 degrees of the original signal.

According to the above, the signal circuit can generate a delay time, in which the first auxiliary switch or the second auxiliary switch of the soft switching circuit can be turned on first, and the first resonant inductor, the first resonant capacitor, and the second are caused. Resonance Sense and the second vibration capacitor form a resonance circuit, so that the voltage between the first main switch or the second main switch first drops to zero, and then the first auxiliary switch or the second auxiliary switch is turned off, and then the first main switch or the first The triggering of the two main switches is turned on to achieve the soft switching characteristic of zero voltage switching; and the first main switch can be connected in parallel with the first resonant capacitor, and the second main switch can be connected in parallel with the second resonant capacitor, so that the first main switch and the first The voltage of the two main switches cannot be changed instantaneously. At this time, the triggering of the first main switch or the second main switch is performed, and zero voltage switching can be achieved; and the first resonant inductor or the second resonant inductor is stored in the resonant circuit. The energy energy, the circuit formed by the conduction of the first auxiliary diode or the second auxiliary diode, releases energy to the load group, thereby achieving the advantages of energy recovery and reuse.

In summary, it can be seen that the interleaved high step-up ratio soft-switching converter to which the present invention is applied can not only reduce the switching loss of the main switching element, but also improve the conversion efficiency of the converter and reduce the switching stress and conduction loss of the switching element. And the modular structure makes the soft switching circuit easy to apply to the interleaved boost circuit. The invention not only provides a simple interleaved high step-up ratio soft-switching converter solution, but also proposes a simple signal circuit, which greatly reduces the complexity of the use of the interleaved high-boost ratio soft-switching converter.

Please refer to FIG. 1 , which is a circuit diagram of an interleaved high step-up ratio soft-switching converter according to an embodiment of the invention. An interleaved boost circuit 100 is electrically coupled to a soft switching circuit 200. The interleaved boost circuit 100 includes a first boost circuit 110 and a second boost circuit 120, and a second The boosting circuit 120 is electrically connected to the first boosting circuit 110. The soft switching circuit 200 includes a first auxiliary circuit 210 and a second secondary circuit 220. The first auxiliary circuit 210 is electrically connected to the second auxiliary circuit 220. The auxiliary circuit 210 includes a first resonant capacitor 211 electrically connected to the first boosting circuit 110, a first resonant inductor 212 electrically connected to the first boosting circuit 110 and the first resonant capacitor 211, and a first auxiliary switch. 213 is electrically connected to the first booster circuit 110 by being electrically connected to the first resonant inductor 212, and electrically connected to the first auxiliary inductor 212 and the first auxiliary switch 213 by a first auxiliary diode 214. The second auxiliary circuit 220 includes a second resonant capacitor 221 electrically connected to the second boosting circuit 120, and a second resonant inductor 222 electrically connected to the second boosting circuit 120 and the second resonant capacitor 221, The second auxiliary switch 223 is electrically connected to the second boosting circuit 120 by being electrically connected to the second resonant inductor 222, and the second auxiliary diode 224 and the second resonant inductor 222 and the second auxiliary switch 223 electrical connection. The first auxiliary switch 213 can be a gold-oxygen half-field effect transistor, and can be connected in parallel with a first auxiliary back-connecting diode 215. The first auxiliary switch 213 has a first auxiliary signal contact 216; the second auxiliary switch 223 It can be a gold-oxygen half-field effect transistor, and can be connected in parallel with a second auxiliary back-up diode 225, and the second auxiliary switch 223 has a second auxiliary signal contact 226.

The first booster circuit 110 can include a first energy storage inductor 111 electrically coupled to the second booster circuit 120, and a first main switch 112 electrically coupled to the first energy storage inductor 111, wherein the first main switch The second booster circuit 120 includes a second energy storage inductor 121 electrically connected to the first booster circuit 110. The second booster circuit 120 includes a second energy storage inductor 121 electrically connected to the first booster circuit 110. And a second main switch 122 and the second energy storage inductor 121 are electrically The connection, wherein the second main switch 122 can be a MOS field effect transistor, and a second main back contact diode 123 can be connected in parallel.

The interleaved boosting circuit 100 further includes a first main diode 130 electrically connected to the first boosting circuit 110, a second main diode 140 and a second boosting circuit 120, and a first main diode. 130 is electrically connected, a clamp capacitor 150 is electrically connected to the first main diode 130 and the second main diode 140, and a load group 160 is electrically connected to the second main diode 140; the load group 160 An output capacitor 161 can be electrically connected to the second main diode 140, and an output resistor 162 is electrically connected to the output capacitor 161.

In accordance with one embodiment of the capacitor of the present embodiment, the first inductor 111 and second inductor 121 may be selected 260 micro Henry (μ H) of the inductor, the clamp capacitance 470 microfarads 150 optional (μ F) of The output capacitor 161 can be selected from a capacitor of 180 microfarads ( μ F); the first main switch 112, the second main switch 122, the first auxiliary switch 213 and the second auxiliary switch 223 can be selected from the type MOSFET IRFP460 The first resonant capacitor 211 and the second resonant capacitor 221 can thus use the stray capacitance of the model MOSFET IRFP460 from the first main switch 112 and the second main switch 122, which is 870 picofarads (pF); the first resonance The inductor 212 and the second resonant inductor 222 can employ a 50 microhenry (μH) inductor. When the embodiment is applied to the boosting of the fuel cell output voltage, the output voltage of the fuel cell is the input voltage V _{i of} the embodiment, which may be 22 to 50 volts (V), and the output voltage across the output resistor 162. V _o can be 300 volts (V), the maximum output power can be 400 watts (W), the output power can be less than 400 watts and greater than 0 watts, the switching frequency is 15 Hz (kHz), and the output resistance 162 is 225. Ohm (Ω).

Please refer to FIG. 2A, which illustrates a schematic diagram of a signal circuit 300 in accordance with an embodiment of the present invention. The signal circuit 300 includes an original signal device 310, a first flip-flop 330, a first AND gate 350, a second flip-flop 340, and a second AND gate 360. The original signal device 310 includes an original signal terminal 311 for generating an original signal PWM1, and a phase shift terminal 312 for generating a phase shift signal PWM2 of the original signal PWM1; the first flip-flop 330 is electrically connected to the original by the contact 1B. The signal terminal 311 has a first output terminal 1Q and a first inversion terminal 1 The first output terminal 1Q can output a first auxiliary signal S _r1 ; the first AND gate 350 is electrically connected to the first inverting terminal 1 And the original signal terminal 311, a first AND gate 350 having a second output terminal 351 may output a first main signal S _1; second flip-flop 340 is electrically connected to the contacts 2B phase shift end 312, a second flip-flop 340 has a third output terminal 2Q and a second inverter terminal 2 The third output terminal 2Q can output a second auxiliary signal S _r2 ; the second AND gate 360 is electrically connected to the second inverting terminal 2 And the phase shift terminal 312, the second gate 360 and a fourth output terminal 361 can output a second main signal S ₂ . The first flip-flop 330 has a contact 1A as a ground, and the first flip-flop 330 has a contact 1R/C, a contact 1C and a contact 1 Forming an electrical connection with a capacitor C, a variable resistor R, and a power source 5V; the second flip-flop 340 has a contact 2A for grounding, and the second flip-flop 340 has a contact 2R/C, a contact 2C, and One contact 2 It is electrically connected to a capacitor C, a variable resistor R and a power source 5V.

Please refer to FIG. 1 and FIG. 2A simultaneously, wherein the first output terminal 1Q, the second output terminal 351, the third output terminal 2Q, and the fourth output terminal 361 are respectively powered. The first auxiliary signal contact 216, the first main signal contact 114, the second auxiliary signal contact 226 and the second main signal contact 124 are connected.

According to an embodiment of the present embodiment, the first flip-flop 330 and the second flip-flop 340 in the signal circuit 300 can be selected as a monostable flip-flop, and the model can be 74LS123; the first gate 350 and the second gate 360 can be The gate type IC7408 is selected; the original signal device 310 can be selected with a PIC microcontroller model PIC18F8720, which can simultaneously generate the original signal PWM1 and the phase shift signal PWM2, wherein the phase shift signal PWM2 can be the 180 degree phase of the original signal PWM1. Displacement.

Please refer to FIG. 2B and FIG. 2A. FIG. 2B is a schematic diagram showing waveforms of signals generated by the signal circuit 300 according to an embodiment of the present invention. When the original signal terminal 311 generates the original signal PWM1 waveform as shown in FIG. 2B, the phase shift signal PWM2 waveform as shown in FIG. 2B and the first output terminal 1Q output signal waveform, that is, the first auxiliary signal, can be obtained from the above. The output signal waveform of the S _r1 waveform and the third output terminal 2Q is the waveform of the second auxiliary signal S _r2 and the first inverting terminal 1 Output signal waveform, second inverting terminal 2 The waveform of the output signal, the output signal waveform of the second output terminal 351 of the first main i.e. waveform signals S _1, and the output signal waveform of the fourth output terminal 361 of the primary signal S ₂ that is a second waveform. If the capacitance value of the capacitor C is C and the resistance value of the variable resistor R is R , the delay time t _sd is: Further, the general delay time t _{sd is} designed to be 5% to 10% of the period of the original signal PWM1 switching control signal. According to an embodiment of the present embodiment, the delay time t _sd is selected to be 6.67 microseconds ( μ s).

Referring to FIG. 3, a waveform diagram of main components of an interleaved high step-up ratio soft-switching converter operating in one cycle according to an embodiment of the present invention is shown. The following notes use a few assumptions to make the description clearer and more concise:

1. It is assumed that each switching element includes a first main switch 112, a first auxiliary switch 213, a second main switch 122, and a second auxiliary switch 223, and each of the diode elements includes a first main diode 130 and a second main unit The pole body 140, the first auxiliary diode 214, the second auxiliary diode 224, the first main backing diode 113, the second main backing diode 123, the first auxiliary backing diode 215, The second auxiliary backing body 225 is regarded as an ideal component, that is, there is no conduction voltage drop, and the on-resistance and the off current are negligible.

2. The first resonant capacitor 211 is the total value of the parasitic capacitance of the first main switch 112 and its applied capacitance; the second resonant capacitor 221 is the total value of the parasitic capacitance of the second main switch 122 and its applied capacitance.

3. Assume that the switching time and the resonance time are relative to the change of the first energy storage inductor 111 current i _L1 , the second energy storage 121 inductor current i _L2 , the clamp capacitor 150 voltage v _{C1 ,} and the output capacitor 161 voltage v _o . It is extremely short, so in the switching period T , the first energy storage inductor 111 current i _L1 , the second energy storage inductor 121 current i _L2 , the clamp capacitor 150 voltage v _C1 and the output capacitor 161 voltage v _o , respectively Treated as a constant value, ie i _L1 = I _L1 , i _L2 = I _L2 , v _C1 = V _C1 , v _o = V _o .

In the following, according to the switching of each switch and the on and off states of the diodes, the state in which the present embodiment operates in one cycle T is divided into 14 operating modes, which are mode 1 to mode 14, respectively, to illustrate the signal waveforms of the main components: Before the mode 1, that is, before the time t is the time point t ₀ , the first main switch 112 and the first auxiliary switch 213 are both turned off, and the second main switch 122 and the first main diode 130 are turned on. It can be seen that the voltage v _ds1 across the first main switch 112 and the voltage across the first resonant capacitor 211 are V _o /2.

Mode 1 is when the time t is between the time point t ₀ and the time point t ₁ , at which time the first main diode 130 is still in the on state, and the first main switch 112 is delayed in conduction, and is preceded by the first auxiliary switch 213 . Turning on, the voltage on the first resonant inductor 212 is V _o /2, and the current i _{Lr 1 of the} first resonant inductor 212 rises linearly from the initial value of zero, and can obtain: When the current i _{Lr 1 of the} first resonant inductor 212 continues to rise to I _{L 1} , the current i _{D 1 of the} first main diode 130 begins to gradually decrease to zero, so the first main diode 130 is turned on and off. State with Zero-current switching (ZCS). In mode 1, the voltage v _Cr 1 of the first resonant capacitor 211 is v _{Cr 1} ( t )= V _o /2, and the current i _D1 flowing through the first main diode 130 is: When the mode 1 terminates at time t is the time point t _1, the time point t ₀ of time from the time point t ₁ pitch T ₁ is:

Mode 2 is when the time t is between the time point t ₁ and the time point t ₂ during which the current i _{Lr 1 of the} first resonant inductor 212 rises to I _{L 1} , and the voltage v _{Cr 1} of the first resonant capacitor 211 is v _{Cr 1} ( t )= V _o /2, the first main diode 130 begins to enter and the first auxiliary switch 213 is continuously turned on, and the first resonant inductor 212 forms a resonant circuit with the first resonant capacitor 211, and the first resonance The current i _{Lr 1 of the} inductor 212 continues to rise, and the voltage v _{Cr 1 of the} first resonant capacitor 211 decreases, and it is obtained: Wherein the resonance impedance Z _o1 is ; resonance frequency ω _o1 is Mode 2 ends when v _{Cr 1} continues to decrease from V _o /2 to zero, at which time time t is time point t ₂ , at which time the current i _{Lr 1} of the first resonant inductor 212 is: _{T. 1} from the time point of time t ₂ T ₂ spacing is:

Mode 3 is when the time t is between the time point t ₂ and the time point t ₃ , in the mode 3, the voltage v _{Cr 1 of the} first resonant capacitor 211 continues to fall to zero, even a slight negative voltage, so that The first main backing diode 113 is turned on, and the voltage v _{ds 1 of the} first main switch 112 is zero; when the time t is equal to the time point t ₃ , the mode 3 is terminated, and the first main switch 112 can be started to be triggered. In order to achieve zero voltage switching, the first auxiliary switch 213 can be switched from the on state to the off state at this time. At this time, the first resonant inductor 212 current i _Lr1 and the first main switch 112 current i _{s 1} are: In order to enable the first main switch 112 to achieve zero-voltage switching (ZVS), the delay time t _{sd of} a main switch 112 can be at least satisfied: According to an embodiment of the present embodiment, the first energy storage circuit 111 current i _{L 1} adopts a peak value thereof, I _{L 1,max} , and after considering a margin time t _r , the delay of the first main switch 112 can be adopted. The time t _sd satisfies the following formula:

Mode 4 is when time t is between time point t ₃ and time point t ₄ . When entering mode 4, first main switch 112 is turned on, first auxiliary switch 213 is turned off; second main switch 122 is turned on, and second auxiliary switch 223 is turned on. At this time, the energy stored to the first resonant inductor 212 is released, and the first secondary diode 214 is turned on to release the energy to the load. When the first auxiliary diode 214 is turned on, the voltage of the first auxiliary switch 213 is V _o , and the voltage of the first resonant inductor 212 is -V _o , so the current i _{Lr 1 of the} first resonant inductor 212 can be obtained: During mode 4, the first resonant inductor 212 releases energy via the first auxiliary diode 214, so the current i _{Lr 1} of the first resonant inductor 212 decreases linearly, and the current i _{Dr 1 of the} first secondary diode 214 Equal to the current i _{Lr 1} of the first resonant inductor 212, the current i _{S 1 of the} first main switch 112 begins to rise linearly. When the time t is equal to the time point t ₄ , the first resonant inductor 212 current i _{Lr 1 is} released to zero, and the current i _{S 1 of the} first main switch 112 rises to I _{L 1} , and the first auxiliary diode 214 follows. As a result, the voltage v _{Sr 1 of the} first auxiliary switch 213 changes to zero, and mode 4 ends. The point of time t from the point of time _{t. 3} of ₄ T ₄ at the pitch:

Mode 5 is when the time t is between the time point t ₄ and the time point t ₅ , during which the first main switch 112 is turned on, the first auxiliary switch 213 is turned off, the second main switch 122 is turned on, and the second auxiliary switch 223 is turned off. At this time, the first main switch 112 current i _S1 , the second main switch 122 current i _S2 , the first resonant capacitor 211 voltage v _Cr1 and the second resonant capacitor 221 voltage v _Cr2 are respectively: i _{S 1} = I _{L 1} , i _{S 2} = I _{L 2} , v _{Cr 1} ( t )=0, v _{Cr 2} ( t )=0, t ₄ t t ₅ ; When the second main switch 122 is turned off, the time t is the time point t ₅ , at which time the mode 5 ends.

Mode 6 is when time t is between time point t ₅ and time point t ₆ . When entering mode 6, the first main switch 112 is turned on, the first auxiliary switch 213 is turned off; the second main switch 122 is turned off, and the second auxiliary switch 223 is also turned off. At this time, the second resonant capacitor 221 is charged, and the second resonant capacitor 221 is charged. The voltage v _Cr2 rises linearly, and the voltage v _{D 2 of the} second main diode 140 decreases linearly from V _o /2, and the voltage v _Cr2 of the second resonant capacitor 221 is obtained as follows: When the voltage v _Cr 2 of the second resonant capacitor 221 rises linearly to V _o /2, mode 6 ends, at which time the second main diode 140 begins to be turned off and has a zero voltage switching property. From the time point _{t. 5} points of time t ₆ and T ₆ is spacing: Mode 7 is when time t is between time point t ₆ and time point t ₇ . During mode 7, the first main switch 112 is turned on, the first auxiliary switch 213 is turned off; the second main switch 122 is turned off, the second auxiliary switch 223 is also turned off, and the energy of the second energy storage inductor 121 and the clamp capacitor 150 is simultaneously released to the output. The capacitor 161 and the load, at this time, the first main switch 112 current i _S1 , the second main switch 122 current i _S2 and the clamp capacitor 150 current i _C1 , the second main diode 140 current i _D2 , the first resonant capacitor 211 voltage i _Cr1 and second resonance capacitor 221 voltage v _Cr2 are: When the second sub-switch 223 is turned on, the time t is the time point t ₇ and the mode 7 ends.

Mode when the time t 8 to time t between time t between the point ₇ to _8. When entering mode 8, the first main switch 112 is turned on, the first auxiliary switch 213 is turned off; the second main switch 122 is turned off, and the second auxiliary switch 223 is turned on, across the second main switch 122, the second resonant capacitor 221, and the clamp The voltage of the capacitor 150 is Vo/2 . During the mode 8, the second main diode 140 is still in the on state, the second main switch 122 is delayed in conduction, and the second auxiliary switch 223 is turned on first, and the voltage on the second resonant inductor 222 is Vo/2 , the second resonance The current i _{Lr 2 of the} inductor 222 rises linearly from zero, so that the current of the second resonant inductor 222 is: When the current i _{Lr2 of the} second resonant inductor 222 continues to rise to I _L2 during the time point t ₇ to the time point t ₈ , the current i _{D 2 of the} second main diode 140 begins to gradually decrease to zero, so the second main The diode 140 has a zero current switching property from the conduction to the off state. During mode 8, the voltage v _{Cr 2} ( t ) of the second resonant capacitor 221 = V _o /2, and the current i _D2 flowing through the second main diode 140 is: When time t is time point t ₈ , mode 8 is terminated. _{T. 7} from the time point of time t ₈ to the pitch T _8:

Mode 9 is when time t is between time point t ₈ and time point t ₉ . During mode 9, the current i _{Lr 2 of the} second resonant inductor 222 continues to rise, the voltage v _{Cr 2} of the second resonant capacitor 221 is v _{Cr 2} ( t )= V _o /2, and the second main diode 140 is turned off. The second auxiliary switch 223 is continuously turned on, and the second resonant inductor 222 and the second resonant capacitor 221 form a resonant circuit. At this time, the current i _{Lr 2 of the} second resonant inductor 222 continues to rise, and the voltage v _{Cr 2 of the} second resonant capacitor 221 decreases. Due to the resonance impedance Z _o2 , the resonance frequency ω _o2 is The current i _{Lr 2 of} the second resonant inductor 222 and the voltage v _{Cr 2 of the} second resonant capacitor 221 are respectively: This mode 9 ends when the voltage v _{Cr 2 of the} second resonant capacitor 221 continues to drop from Vo/2 to zero. At the end of mode 9, time t is time point t ₉ , at which time the current i _{Lr 2} of the second resonant inductor 222 is: From the point of time t time _{t. 8 9 9} as the pitch T:

Mode when the time t 10 to time t between time t between the points ₉ to _10. During the mode 10, the voltage V _{Cr 2 of the} second resonant capacitor 221 of the receiving mode 9 continues to drop to a slight negative voltage, so that the second main backing diode 123 is turned on, and the voltage of the second main switch 122 is V _{ds. 2} is zero. When the time t is the time point t ₁₀ , the mode 10 is terminated, and at the same time, the second main switch 122 is started to be triggered to achieve zero voltage switching, and the second auxiliary switch 223 is switched from the on state to the off state. The current i _{Lr2 of} the second resonant inductor 222 and the current i _S2 of the second main switch 122 are: In order for the second main switch 122 to achieve zero voltage switching, the delay time t _sd can be at least satisfied by: In order to ensure zero voltage switching, according to an embodiment of the present embodiment, the maximum value of the current I _{L 2} of the second energy storage inductor 121 is selected, that is, the peak value I _{L 2,max of} i _{L 2} at full load is The delay time t _{sd is} calculated. Since the delay time t _sd is usually selected as 5% to 10% of the switching period T, since the delay time t _sd is very short, the influence on the interleaved boost circuit is not large, considering the second main switch 122 The recovery process can be fully entered and the second auxiliary switch 223 enters the cutoff, and a margin time t _{r is} considered to obtain a more reliable delay time t _sd to ensure that the above condition is satisfied. Therefore, the delay time t _sd of the second main switch 122 is:

Mode 11 is when time t is between time point t ₁₀ and time point t ₁₁ . When entering mode 11, the first main switch 112 is turned on, the first auxiliary switch 213 is turned off; the second main switch 122 is turned on, and the second auxiliary switch 223 is turned off, and the energy stored to the second resonant inductor 222 is stored by the second auxiliary Diode 224 conducts to release energy to the load. When the second auxiliary diode 224 is turned on, the voltage across the second auxiliary switch 223 is Vo , and the voltage at the end of the second resonant inductor 222 is - Vo . The second resonant inductor 222 current i _Lr2 is obtained as follows: During mode 11, the second resonant inductor 222 releases energy via the second auxiliary diode 224, so that the current i _{Lr 2} of the second resonant inductor 222 decreases linearly, and the current i _{Dr 2 of the} second secondary diode 224 Equal to the current i _{Lr 2} of the second resonant inductor 222, the current i _{S 2 of the} second main switch 122 begins to rise linearly. When the time t is the time point t ₁₁ , the current i _{Lr 2 of the} second resonant inductor 222 is released to zero, and the current i _{S 2 of the} second main switch 122 rises to I _{L 2} , and the second auxiliary diode 224 follows At the end, the voltage V _{Sr 2 of the} second auxiliary switch 223 is reduced to zero, at which time the mode 11 ends. ₁₀ from the point of time t time t ₁₁ T ₁₁ is the spacing:

Mode 12 is when time t is between time point t ₁₁ and time point t ₁₂ . In mode 12, the first main switch 112 is turned on, the first auxiliary switch 213 is turned off; the second main switch 122 is turned on, and the second auxiliary switch 223 is turned off. At this time, the first main switch 112 current i _S1 and the second main switch are obtained. 122 current i _S2 , first resonant capacitor 211 voltage v _Cr1 and second resonant capacitor 221 voltage v _Cr2 are: i _{S 1} = I _{L 1} , i _{S 2} = I _{L 2} , v _{Cr 1} ( t )=0, v _{Cr 2} ( t )=0, t ₁₁ t t ₁₂ ; When the first main switch 112 is turned off, the time t is the time point t ₁₂ and the mode 12 is terminated.

Mode 13 is when time t is between time point t ₁₂ and time point t ₁₃ . When the mode 13 is entered, the first main switch 112 is turned off, the first auxiliary switch 213 is turned off, the second main switch 122 is continuously turned on, and the second auxiliary switch 223 is turned off. At this time, the first resonant capacitor 211 is charged, and the voltage of the first resonant capacitor 211 is turned on. v _C r1 rises in a straight line, and the voltage v _{D1 of the} first main diode 130 decreases linearly from Vo/2, and the voltage v _Cr1 of the first resonant capacitor 211 is obtained as follows: When the voltage v _Cr 1 of the first resonant capacitor 211 rises linearly to Vo/2 , the mode 13 ends, and the first main diode 130 starts to enter the on state from the off state and has a zero voltage switching property. _{12 is} a time point t ₁₃ from the point of time t as the spacing T _13:

Mode 14 is when time t is between time point t ₁₃ and time point t ₁₄ . When the time t is the time point t ₁₄ , the circuit configuration returns to the same circuit configuration as the time t is the time point t ₀ , that is, the operation from the mode 1 to the mode 14 is completed. During mode 14, the first main switch 112 is turned off, the first sub-switch 213 is turned off, the second main switch 122 is turned on, and the second sub-switch 223 is turned off. During this period, the first main diode 130 is turned on, and the energy of the first energy storage inductor 111 is released to the clamp capacitor 150 to charge the clamp capacitor 150. At this time, the voltage of the first resonant capacitor 211 is Vo/2 . The current i _{D 1} of the first main diode 130 is i _{D 1} (t)= I _{L 1} . When the time t is the time point t ₁₄ , the first main switch 112 current i _S1 , the second main switch 122 current i _S2 , the first resonant capacitor 211 voltage v _Cr1 , and the second resonant capacitor 221 voltage v _Cr2 are: When the time t is the time point t ₁₄ , the mode 14 ends, and the circuit configuration at this time is the same as the circuit configuration when the time t is the time point t ₀ .

The interleaving according to the present embodiment can be known from the analysis of the above modes. a high step-up ratio soft-switching converter, a first main switch 112, a second main switch 122, a first auxiliary switch 213, a second auxiliary switch 223, a first main diode 130, a second main diode 140, The soft switching characteristics of the first auxiliary diode 214 and the second auxiliary diode 224 are as follows: the first main switch 112 and the second main switch 122 have zero voltage switching and zero current switching properties when turned on; the first main switch 112 And the second main switch 122 has zero voltage switching property when turned off; the first main diode 130 and the second main diode 140 have zero voltage switching property when turned on; the first main diode 130 and the second main The diode 140 has zero current switching property when turned off; the first auxiliary switch 213 and the second auxiliary switch 223 have zero current switching property when turned on; the first auxiliary diode 214 and the second auxiliary diode 224 are turned on. The utility model has zero voltage switching and zero current switching properties; the first auxiliary diode 214 and the second auxiliary diode 224 also have zero voltage switching and zero current switching properties when turned off.

The first resonant capacitor 211 may be a parasitic capacitor or an external capacitor of the first main switch 112, and the second resonant capacitor 221 may be a parasitic capacitor or an external capacitor of the second main switch 122.

In addition, according to the embodiment of the present invention, the soft switching circuit 200 and the signal circuit 300 can be independent of the interleaved boosting circuit 100 to form a modular structure, and the soft switching circuit 200 can be electrically connected and operated independently. The hard-switched interleaved high-boost ratio converter is controlled by the signal circuit 300, so that the conventional hard-switching interleaved high-boost ratio converter can be implemented at a low cost and using the original circuit architecture. The architecture proposed by the present invention is applied to further enjoy the advantages of applying the present invention.

The embodiment of the present invention is not limited to the secondary architecture described in this embodiment. When the interleaved booster circuit 100 has more main switching components, the soft switching circuit 200 also has more auxiliary switching components and resonant capacitive components. And the resonant inductor element, and the calculation method of the delay time t _sd can also be obtained by using the above description, and the corresponding signal circuit 300 can be obtained.

It can be seen from the above embodiments of the present invention that the application of the present invention has the following advantages:

1. Reduce the switching loss of the main switching element, thereby improving the conversion efficiency of the converter.

2. Reduce the switching stress and conduction loss of the switching elements.

3. Provide modular structure, easy to implement interleaved high step-up ratio soft-switching converter, and easy to improve the conventional hard-switching interleaved high-boost ratio converter to become interleaved high-boost ratio soft-switching conversion Device.

4. The proposed circuit architecture is simple, and it is much easier to implement an interleaved high step-up ratio soft-switching converter.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100‧‧‧Interleaved boost circuit

110‧‧‧First booster circuit

111‧‧‧First energy storage inductor

112‧‧‧First main switch

113‧‧‧The first main backing diode

114‧‧‧First main signal contact

120‧‧‧second boost circuit

121‧‧‧Second energy storage inductance

122‧‧‧Second main switch

123‧‧‧Second main backing diode

124‧‧‧second main signal contact

130‧‧‧First main diode

140‧‧‧Second main diode

150‧‧‧Clamp Capacitor

160‧‧‧Load group

161‧‧‧Output capacitor

162‧‧‧Output resistance

200‧‧‧Soft Switching Circuit

210‧‧‧First auxiliary circuit

211‧‧‧First Resonance Capacitor

212‧‧‧First Resonance Inductance

213‧‧‧First auxiliary switch

214‧‧‧First secondary diode

215‧‧‧First auxiliary backing diode

216‧‧‧First auxiliary signal contact

220‧‧‧second secondary circuit

221‧‧‧Second resonant capacitor

222‧‧‧Second resonant inductor

223‧‧‧Second auxiliary switch

224‧‧‧Second secondary diode

225‧‧‧Second auxiliary backing diode

226‧‧‧second secondary signal contact

300‧‧‧Signal circuit

310‧‧‧original signalling device

311‧‧‧ original signal end

312‧‧‧ phase shift end

330‧‧‧First trigger

340‧‧‧second trigger

350‧‧‧First Gate

351‧‧‧second output

360‧‧‧Second Gate

361‧‧‧ fourth output

i _D1 ‧‧‧The current of the first main diode

i _D2 ‧‧‧second main diode current

i _Lr1 ‧‧‧The current of the first resonant inductor

i _Lr2 ‧‧‧second resonant inductor current

i _S1 ‧‧‧The current of the first main switch

i _S2 ‧‧‧second main switch current

i _Sr1 ‧‧‧The current of the first auxiliary switch

i _Sr2 ‧‧‧second auxiliary switch current

v _ds1 ‧‧‧voltage of the first main switch

v _ds2 ‧‧‧voltage of the second main switch

v _D1 ‧‧‧The voltage of the first main diode

v _D2 ‧‧‧Voltage of the second main diode

v _Sr1 ‧‧‧The voltage of the first auxiliary switch

v _Sr2 ‧‧‧ voltage of the second auxiliary switch

S ₁ ‧‧‧first main signal

S ₂ ‧‧‧second main signal

S _r1 ‧‧‧first auxiliary signal

S _r2 ‧‧‧second secondary signal

t ‧‧‧Time

t ₀ -t ₁₄ ‧‧‧ time

V _i ‧‧‧ input voltage

V _o ‧‧‧output voltage

PWM1‧‧‧ original signal

PWM2‧‧‧ phase shift signal

1Q‧‧‧ first output

1 ‧‧‧first inverting end

2Q‧‧‧ third output

2 ‧‧‧Second inverting end

1A, 1B, 1R/C, 1C, 1 , 1Q, 1 , 2A, 2B, 2R/C, 2C, 2 , 2Q, 2 ‧‧‧contact

SV‧‧‧ voltage source

C‧‧‧ capacitor

R‧‧‧Variable resistor

The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; A circuit diagram of a softer switching converter.

2A is a schematic diagram showing a signal circuit in accordance with an embodiment of the present invention.

FIG. 2B is a schematic diagram showing the waveform of a signal generated by a signal circuit according to an embodiment of the present invention.

3 is a waveform diagram showing main components of an interleaved high step-up ratio soft-switching converter operating in one cycle according to an embodiment of the present invention.

100‧‧‧Interleaved boost circuit

110‧‧‧First booster circuit

111‧‧‧First energy storage inductor

112‧‧‧First main switch

113‧‧‧The first main backing diode

114‧‧‧First main signal contact

120‧‧‧second boost circuit

121‧‧‧Second energy storage inductance

122‧‧‧Second main switch

123‧‧‧Second main backing diode

124‧‧‧second main signal contact

130‧‧‧First main diode

140‧‧‧Second main diode

150‧‧‧Clamp Capacitor

160‧‧‧Load group

161‧‧‧Output capacitor

162‧‧‧Output resistance

200‧‧‧Soft Switching Circuit

210‧‧‧First auxiliary circuit

211‧‧‧First Resonance Capacitor

212‧‧‧First Resonance Inductance

213‧‧‧First auxiliary switch

214‧‧‧First secondary diode

215‧‧‧First auxiliary backing diode

216‧‧‧First auxiliary signal contact

220‧‧‧second secondary circuit

221‧‧‧Second resonant capacitor

222‧‧‧Second resonant inductor

223‧‧‧Second auxiliary switch

224‧‧‧Second secondary diode

225‧‧‧Second auxiliary backing diode

226‧‧‧second secondary signal contact

V _i ‧‧‧ input voltage

V _o ‧‧‧output voltage

Claims (10)

An interleaved high step-up ratio soft-switching converter comprising: an interleaved boost circuit comprising: a first boost circuit, and a second boost circuit electrically coupled to the first boost circuit And a soft switching circuit electrically connected to the interleaved boosting circuit, the soft switching circuit comprising: a first auxiliary circuit comprising: a first resonant capacitor electrically coupled to the first boosting circuit a first resonant inductor electrically connected to the first boosting circuit and the first resonant capacitor; a first auxiliary switch electrically connected to the first resonant inductor and the first rising The voltage circuit is electrically connected; and a first auxiliary diode electrically connected to the first resonant inductor and the first auxiliary switch; and a second auxiliary circuit comprising: a second resonant capacitor, and The second boosting circuit is electrically connected; a second resonant inductor is electrically connected to the second boosting circuit and the second resonant capacitor; and a second auxiliary switch is electrically connected to the second resonant inductor The second booster circuit is electrically connected to the second booster circuit, and is electrically connected to the second resonant inductor and the second auxiliary switch. The interleaved high step-up ratio soft-switching converter of claim 1, wherein the first boosting circuit comprises: a first energy storage inductor electrically connected to the second boosting circuit; and a first main And a switch electrically connected to the first energy storage inductor. The interleaved high step-up ratio soft-switching converter of claim 1, wherein the second boosting circuit comprises: a second energy storage inductor electrically connected to the first boosting circuit; and a second main And a switch electrically connected to the second energy storage inductor. The interleaved high step-up ratio soft-switching converter of claim 1, wherein the interleaved boosting circuit further comprises: a first main diode, electrically connected to the first boosting circuit; and a second main a diode, electrically connected to the second booster circuit and the first main diode; a clamp capacitor electrically connected to the first main diode and the second main diode; And a load group electrically connected to the second main diode, the load group comprising: An output capacitor electrically connected to the second main diode; and an output resistor electrically connected to the output capacitor. The interleaved high step-up ratio soft-switching converter of claim 1, further comprising a signal circuit electrically coupled to the interleaved boosting circuit, the signal circuit comprising: an original signal device comprising: an original a signal end, which can output an original signal; and a phase shift end, which can output a phase shift signal of the original signal; a first flip-flop electrically connected to the original signal end, the first trigger has a a first output end and a first inverting end; a first AND gate electrically connected to the first inverting end and the original signal end, the first and the second side of the brake device; a second a trigger is electrically connected to the phase shifting end, the second trigger has a third output end and a second inverting end, and a second gate is electrically connected to the second inverting end and The second output end, the second output end, the third output end, and the fourth output end are electrically connected to the first auxiliary switch, respectively a first main switch, the second auxiliary switch, and the second main switch. The interleaved high step-up ratio soft-switching converter of claim 5, wherein the original signal device is a PIC microcontroller. The interleaved high step-up ratio soft-switching converter of claim 5, wherein the first flip-flop and the second flip-flop are monostable flip-flops. The interleaved high step-up ratio soft-switching converter of claim 1, wherein the first resonant capacitor is an external capacitor or a stray capacitance of the first main switch, and the second resonant capacitor is an external capacitor or a second main The stray capacitance of the switch. The interleaved high step-up ratio soft-switching converter of claim 1, wherein the first auxiliary switch and the second auxiliary switch are gold-oxygen half field effect transistors. The interleaved high step-up ratio soft-switching converter of claim 9, wherein the first auxiliary switch and the second auxiliary switch are each connected in parallel with a diode.