CN209233726U - A kind of tri-lever boosting circuit - Google Patents

Abstract

The utility model discloses a kind of tri-lever boosting circuit, comprising: DC power supply DC, boost inductance L1, power switch tube Q1, power switch tube Q2, output bus filter capacitor C1, output bus filter capacitor C2, capacitor C3, diode D1, diode D2, clamp diode D3 and energy converter.The utility model solves the problems, such as series power switch pipe Q1 and power switch tube Q2 unbalanced-voltage-division as caused by the presence of parasitic inductance L2.

Description

A kind of tri-lever boosting circuit

Technical field

The utility model relates to field of power electronics more particularly to a kind of tri-lever boosting circuits.

Background technique

Now in order to reduce photovoltaic system cost, the inverter of present high-pressure system is more more and more universal, photovoltaic MPPT (Maximum Power Point Tracking, MPPT maximum power point tracking) optimizing mostly uses Boost circuit, compares in the market General power switch tube is difficult to bear higher voltage, so now many all use two concatenated modes of power switch tube It boosts, but since the switching speed of two power switch tubes is very fast, along with placement-and-routing is difficult to reach ideal effect, Parasitic inductance is constantly present, and causes circuit that can not work normally.

Utility model content

The purpose of this utility model is that being mentioned by a kind of tri-lever boosting circuit to solve background section above The problem of.

For this purpose, the utility model uses following technical scheme:

A kind of tri-lever boosting circuit, the circuit include: DC power supply DC, boost inductance L1, power switch tube Q1, power Switching tube Q2, output bus filter capacitor C1, output bus filter capacitor C2, capacitor C3, diode D1, diode D2, clamper Diode D3 and energy converter；Wherein, one end of the anode connection boost inductance L1 of the DC power supply DC, DC power supply First wiring of the emitter, one end, energy converter of output bus filter capacitor C2 of the cathode and power switch tube Q2 of DC End connection, the other end of boost inductance L1 are connect with the collector of the anode of diode D1, power switch tube Q1, diode D1's Cathode is connect with the anode of one end of capacitor C3, diode D2, the other end of capacitor C3 and emitter, the function of power switch tube Q1 One end connection of the collector, parasitic inductance L2 of rate switching tube Q2, the other end and clamp diode D3 of parasitic inductance L2 is just The other end of pole connection, the cathode of clamp diode D3 and output bus filter capacitor C2 export the one of bus filter capacitor C1 The second terminals connection at end, energy converter, exports the other end of bus filter capacitor C1 and cathode, the energy of diode D2 The third terminals of converter connect.

Particularly, the tri-lever boosting circuit further include: the junction capacity C4 of power switch tube Q1, power switch tube Q2 Junction capacity C5, junction capacity C4 are attempted by between the collector and emitter of power switch tube Q1, and junction capacity C5 is attempted by power and opens Between the collector and emitter for closing pipe Q2.

The utility model proposes tri-lever boosting circuit efficiently solve series power switch pipe Q1 and power switch tube Q2 unbalanced-voltage-division as caused by there are problems that of parasitic inductance L2.

Detailed description of the invention

Fig. 1 is photovoltaic power generation system structure schematic diagram provided by the embodiment of the utility model；

Fig. 2 is the tri-lever boosting circuit structure diagram that the utility model embodiment one provides；

Fig. 3 is the tri-lever boosting circuit structure diagram that the utility model embodiment two provides；

The driver' s timing that Fig. 4 is the power switch tube Q1 that the utility model embodiment two provides and power switch tube Q2 is illustrated Figure.

Specific embodiment

The utility model is more fully retouched below with reference to relevant drawings for the ease of understanding the utility model, It states.The preferred embodiment of the utility model is given in attached drawing.But the utility model can come in many different forms in fact It is existing, however it is not limited to embodiment described herein.On the contrary, purpose of providing these embodiments is makes public affairs to the utility model Open the more thorough and comprehensive of content understanding.It should be noted that it can when an element is considered as " connection " another element To be directly to another element or may be simultaneously present centering elements.Unless otherwise defined, institute used herein Some technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the utility model belongs.Herein In term used in the description of the utility model be only for the purpose of describing specific embodiments and be not intended to Limit the utility model.Term " and or " used herein include the arbitrary of one or more relevant listed items and All combinations.

It please refers to shown in Fig. 1, Fig. 1 is photovoltaic power generation system structure schematic diagram provided by the embodiment of the utility model.This reality Applying middle photovoltaic generating system mainly includes that photovoltaic group string, photovoltaic DC-to-AC converter, grid-connected transformer etc. are constituted.Photovoltaic DC-to-AC converter mainly wraps Include two parts DC/DC and DC/AC.Due to the individual difference or light differential of different photovoltaic modulies, each photovoltaic is caused Group string output voltage it is different, pass through control DC/DC, it is ensured that every road photovoltaic group string can with maximum power output, To realize the function (MPPT) of maximum power tracing, the generating efficiency of inverter is improved, there is the performance of inverter in the side DC/DC It is most important to act on.Because Boost circuit control is relatively easy, and is easily achieved, the DC/ of most of photovoltaic DC-to-AC converter DC circuit is all using Boost circuit, and the tri-lever boosting circuit that Examples below one, embodiment two provide is in light Typical case in photovoltaic generating system.

As shown in Fig. 2, Fig. 2 is the tri-lever boosting circuit structure diagram that the utility model embodiment one provides.The present embodiment Middle tri-lever boosting circuit specifically includes: DC power supply DC, boost inductance L1, power switch tube Q1, power switch tube Q2, output Bus filter capacitor C1, output bus filter capacitor C2, capacitor C3, diode D1, diode D2, clamp diode D3 and energy Energy converter；Wherein, one end of the anode connection boost inductance L1 of the DC power supply DC, the cathode and power of DC power supply DC The first terminals connection of the emitter of switching tube Q2, the one end for exporting bus filter capacitor C2, energy converter, boost inductance The other end of L1 is connect with the collector of the anode of diode D1, power switch tube Q1, and the cathode of diode D1 is with capacitor C3's The anode connection of one end, diode D2, the other end and the emitter of power switch tube Q1, the collection of power switch tube Q2 of capacitor C3 One end connection of electrode, parasitic inductance L2, the other end of parasitic inductance L2 are connect with the anode of clamp diode D3, two pole of clamper The other end of the cathode of pipe D3 and output bus filter capacitor C2, one end for exporting bus filter capacitor C1, energy converter The other end of the connection of second terminals, output bus filter capacitor C1 connects with the cathode of diode D2, the third of energy converter Line end connection.Energy converter preferably uses balancing circuitry in the present embodiment.

As shown in figure 3, Fig. 3 is the tri-lever boosting circuit structure diagram that the utility model embodiment two provides.The present embodiment Middle tri-lever boosting circuit specifically includes: DC power supply DC, boost inductance L1, power switch tube Q1, power switch tube Q2, output Bus filter capacitor C1, output bus filter capacitor C2, capacitor C3, diode D1, diode D2, clamp diode D3, energy The junction capacity C5 of converter, the junction capacity C4 of power switch tube Q1 and power switch tube Q2；Wherein, the DC power supply DC One end of anode connection boost inductance L1, emitter, the output bus filtering of the cathode and power switch tube Q2 of DC power supply DC The first terminals connection of one end, energy converter of capacitor C2, the other end of boost inductance L1 and anode, the function of diode D1 The collector of rate switching tube Q1 connects, and the cathode of diode D1 is connect with the anode of one end of capacitor C3, diode D2, capacitor C3 The other end connect with one end of the emitter of power switch tube Q1, the collector of power switch tube Q2, parasitic inductance L2, knot electricity Hold C4 to be attempted by between the collector and emitter of power switch tube Q1, junction capacity C5 is attempted by the collector of power switch tube Q2 Between emitter, the other end of parasitic inductance L2 connect with the anode of clamp diode D3, the cathode of clamp diode D3 and Export the second terminals company of the other end of bus filter capacitor C2, the one end for exporting bus filter capacitor C1, energy converter It connects, the other end of output bus filter capacitor C1 is connect with the third terminals of the cathode of diode D2, energy converter.At this Energy converter can will export in energy transfer to total bus extra on bus filter capacitor C2 in embodiment, defeated to guarantee Electric voltage equalization on bus filter capacitor C1 and output bus filter capacitor C2 out.

As shown in figure 4, when work, the gate drive voltage of power switch tube Q1 and power switch tube Q2 original state all For low level, when digital signal processor (DSP) gives one high level signal of gate pole of power switch tube Q1, power switch tube Q1 is open-minded, current loop at this time are as follows: DC source DC- boost inductance L1- power switch tube Q1- clamp diode D3- output is female Line filter capacitor C2.After the t1 time, to one high level signal of gate pole of power switch tube Q2, power switch tube Q2 opens DSP It is logical, current loop at this time are as follows: DC source DC- boost inductance L1- power switch tube Q1- power switch tube Q2, power switch tube Q1 is connected for a period of time with power switch tube Q2, and in this period, boost inductance L1 energy storage, then power switch tube Q2 is turned off, Current loop at this time is: DC source DC- boost inductance L1- power switch tube Q1- clamp diode D3- exports bus filtered electrical Hold C2, power switch tube Q2 shutdown after, after the t2 time, DSP to power switch tube Q1 one low level signal of gate pole, Power switch tube Q1 shutdown, power switch tube Q1 is during shutdown, since parasitic inductance L2 needs continuous current circuit, at this time Afterflow is afterflow to be carried out by capacitor C3, rather than carry out afterflow by junction capacity C5, so not will lead to power switch tube Q1 It is uneven with the voltage of power switch tube Q2.And if removing the capacitor C3 of tri-lever boosting circuit in the utility model: power is opened The gate drive voltage of pass pipe Q1 and power switch tube Q2 is all low level in original state, when DSP is to power switch tube Q1's When one high level signal of gate pole, power switch tube Q1 is open-minded, and current loop at this time is DC source DC- boost inductance L1- function Rate switching tube Q1- clamp diode D3- exports bus filter capacitor C2.After the t1 time, gate pole of the DSP to power switch tube Q2 One high level signal, power switch tube Q2 are open-minded, current loop at this time are as follows: DC source DC- boost inductance L1- power switch Pipe Q1- power switch tube Q2, power switch tube Q1 and power switch tube Q2 are connected for a period of time, in this period, boost inductance L1 energy storage, then power switch tube Q2 is turned off, and current loop at this time is: DC source DC- boost inductance L1- power switch tube Q1- clamp diode D3- exports bus filter capacitor C2, and after power switch tube Q2 shutdown, after the t2 time, DSP is to function One low level signal of gate pole of rate switching tube Q1, power switch tube Q1 shutdown, power switch tube Q1 during shutdown, by Need continuous current circuit in parasitic inductance L2, thus parasitic inductance L2 will from the junction capacity C5 extracting energy of power switch tube Q2, Leading to the voltage at the both ends power switch tube Q2 reduces.Cause the voltage of power switch tube Q1 and power switch tube Q2 uneven at this time, It is possible that will lead to the risk of power switch tube Q1 over-voltage.

The technical solution of the utility model efficiently solves series power switch pipe Q1 and power switch tube Q2 due to parasitism Unbalanced-voltage-division caused by there are problems that of inductance L2.

Note that above are only the preferred embodiment and institute's application technology principle of the utility model.Those skilled in the art's meeting Understand, the utility model is not limited to specific embodiment described here, is able to carry out for a person skilled in the art various bright Aobvious variation, readjustment and substitution is without departing from the protection scope of the utility model.Therefore, although passing through above embodiments The utility model is described in further detail, but the utility model is not limited only to above embodiments, is not departing from It can also include more other equivalent embodiments in the case that the utility model is conceived, and the scope of the utility model is by appended Scope of the claims determine.

Claims (2)

1. a kind of tri-lever boosting circuit characterized by comprising DC power supply DC, boost inductance L1, power switch tube Q1, Power switch tube Q2, output bus filter capacitor C1, output bus filter capacitor C2, capacitor C3, diode D1, diode D2, Clamp diode D3 and energy converter；Wherein, one end of the anode connection boost inductance L1 of the DC power supply DC, direct current The emitter of the cathode of power supply DC and power switch tube Q2, the one end for exporting bus filter capacitor C2, energy converter first Terminals connection, the other end of boost inductance L1 are connect with the collector of the anode of diode D1, power switch tube Q1, diode The cathode of D1 is connect with the anode of one end of capacitor C3, diode D2, the transmitting of the other end and power switch tube Q1 of capacitor C3 One end connection of pole, the collector of power switch tube Q2, parasitic inductance L2, the other end and clamp diode D3 of parasitic inductance L2 Anode connection, the other end, the output bus filter capacitor C1 of the cathode of clamp diode D3 and output bus filter capacitor C2 One end, energy converter the second terminals connection, export bus filter capacitor C1 the other end and diode D2 cathode, The third terminals of energy converter connect.

2. tri-lever boosting circuit according to claim 1, which is characterized in that further include: the knot electricity of power switch tube Q1 Hold the junction capacity C5 of C4, power switch tube Q2, junction capacity C4 is attempted by between the collector and emitter of power switch tube Q1, is tied Capacitor C5 is attempted by between the collector and emitter of power switch tube Q2.