CN105896974A - High-gain direct-current voltage-boosting conversion circuit - Google Patents

Abstract

The invention discloses a high-gain direct-current voltage-boosting conversion circuit, and belongs to the technical field of electric power conversion circuit. The positive electrode of an input power supply is connected with one end of conversion circuit inductor and the positive electrode of a charging diode; the negative electrode of the input power supply is connected with the emitting electrode of a conversion circuit switch tube, the low-potential end of a conversion circuit output filtering capacitor and the low-potential end of a conversion circuit output load equivalent resistor; the other end of the conversion circuit inductor is connected with the collector electrode of the conversion circuit switch tube and the low-potential end of a conversion circuit capacitor; the negative electrode of the charging diode is connected with the high-potential end of the conversion circuit capacitor and the positive electrode of a conversion circuit voltage-boosting diode; and the negative electrode of the conversion circuit voltage-boosting diode is connected with the high-potential end of the conversion circuit output filtering capacitor and the high-potential end of the conversion circuit output load equivalent resistor. According to the conversion circuit provided by the invention, voltage-boosting and conversion control on the direct-current voltage is implemented; an output voltage gain which is higher than that of the single-stage voltage-boosting chopping wave conversion circuit is obtained; and in addition, the high-gain direct-current voltage-boosting conversion circuit is simple in circuit structure and high in efficiency.

Description

A kind of high-gain DC boost conversion circuit

Technical field

The invention belongs to power transformation circuit technical field, be specifically related to a kind of high-gain DC boost conversion circuit.

Background technology

Currently, nervous based on global energy and fossil energy uses the impact produced to environment, wind energy and solar energy Accepted widely by the whole society etc. regenerative resource and obtaining application.But, in the exploitation of regenerative resource In application process, owing to being affected by factors such as wind speed, illumination, weathers, the use of regenerative resource is subject to The biggest restriction, the stochastic volatility of its energy is the biggest obstacle that regenerative resource is used effectively, and how to allow Renewable energy power generation device produces more stable electric energy in the case of wind-force, illumination variation, is renewable Energy electricity generation system needs the important step of configuration.

Especially in photovoltaic generating system, because voltage produced by light cell is relatively low, hidden by cloud layer at photovoltaic cell Under the influence of the factors such as gear, light intensity decreasing, its output voltage will be lower, for effectively using in broader scope Luminous energy, needs Voltage Cortrol produced by light cell to suitable scope, and implements maximal power tracing (MPPT) control, need, at light cell outfan configuring direct current boost conversion circuit, to be produced by photovoltaic cell Electric energy boost to set point.In directly-driving wind power generation system, the alternating current of its electromotor output is rectified Change with ambient wind velocity is changed by the DC voltage of circuit output, to produced electric energy is transmitted best friend Stream electrical network, before implementing inversion, it is necessary to makes the input direct voltage of inverter control within the scope of suitable. Wider in view of directly-driving wind power generation system wind speed excursion in use, wish again wind-power electricity generation system System Maximum Power Output under any wind regime, needs to implement MPPT and controls, accordingly, it would be desirable to wind-power electricity generation System output voltage implements boosting or blood pressure lowering controls, in order to control the input voltage of inverter in suitable scope. Thus, in field of new energy generation, boost conversion circuit is widely used.

Boosting inverter obtains and applies most typical circuit is Boost translation circuit, is considering boost conversion circuit unit In the case of part actual parameter, in dutycycle controlled range, its step-up ratio is the most little, to renewable energy power generation The energy that system makes full use of environment is unfavorable, and configuring multistage boost conversion circuit affects the operational efficiency of system again, Needing to make an effort in terms of the high-gain, simplification of boost conversion circuit, the present invention is that a kind of reality is reliable High-gain, high efficiency DC boosting translation circuit.

Summary of the invention

Goal of the invention: it is an object of the invention to provide a kind of high-gain DC boost conversion circuit, circuit structure Simply, easy to control, efficiency is high, and the boosting inverter implementing DC voltage controls, it is thus achieved that ratio single-stage boost chopper The output voltage gain that translation circuit is high.

Technical scheme: for achieving the above object, the present invention adopts the following technical scheme that

A kind of high-gain DC boost conversion circuit, including input power E, translation circuit inductance L₁, conversion electricity Road electric capacity C₁, translation circuit output filter capacitor C₀, charging diode D₁, translation circuit booster diode D₂With translation circuit switch transistor T；The positive pole of described input power E and translation circuit inductance L₁One end, fill Electric diode D₁Anode be connected, the negative pole of described input power E and the emitter stage of translation circuit switch transistor T (being source electrode during field effect transistor), translation circuit output filter capacitor C₀Cold end, translation circuit output loading The cold end of equivalent resistance R is connected；Described translation circuit inductance L₁The other end and translation circuit switch The colelctor electrode (being drain electrode during field effect transistor) of pipe T, translation circuit electric capacity C₁Cold end be connected, charge two Pole pipe D₁Negative electrode and translation circuit electric capacity C₁Hot end, translation circuit booster diode D₂Anode It is connected, translation circuit booster diode D₂Negative electrode and translation circuit output filter capacitor C₀Hot end, The hot end of translation circuit output loading equivalent resistance R is connected.

If circuit output voltage pulsation scope control stationary value ± 1%, translation circuit output filter capacitor C₀Meet formula (I):

$C_o\≥\frac{T_s}{5R}---\left(I\right);$

Wherein: R is changer output loading equivalent resistance, T_sFor the switch controlled cycle.

If converter circuit needs the peak power changed to be P_Max, the pulsation of changer input current is less than steady-state value 10%, the maximum of converter circuit input current: I_Max=P_Max/ E, described translation circuit inductance L₁ Rated current I_L1e=I_Max, translation circuit inductance

When translation circuit switch transistor T is opened, is turned off work:

Translation circuit switch transistor T rated current I_Te=(1.2:1.5) I_Max；

Translation circuit switch transistor T rated voltageWherein, translation circuit leaves The dutycycle closing pipe T is

When translation circuit switch transistor T is opened, is turned off work:

Described translation circuit booster diode D₂Rated current I_D2e=(1.2:1.5) I_Max；

Described charging diode D₁Rated current I_D1e=(2.0:3.0) I_Max；

Described charging diode D₁Rated voltage

Described translation circuit booster diode D₂Rated voltage

When translation circuit switch transistor T is opened, is turned off work:

Described translation circuit electric capacity C₁Rated voltage U_C1e=(1.5:2.0) E；

Described translation circuit output filter capacitor C₀Rated voltage

Beneficial effect: compared with prior art, the high-gain DC boost conversion circuit of the present invention by inductance element, Capacity cell realizes charged in parallel, discharged in series, is promoted by input direct voltage；By single switch management and control Inductance element processed, the charged in parallel of capacity cell, discharged in series, the boosting inverter implementing DC voltage controls, Obtaining the output voltage gain higher than single-stage boost chopper translation circuit, circuit structure is simple, easy to control, effect Rate is high.

Accompanying drawing explanation

Fig. 1 is high-gain DC boost conversion circuit；

Fig. 2 is switching tube circuit operation when opening；

Circuit operation when Fig. 3 is switching tube disconnection.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is described further.

Fig. 1 is high-gain DC boost conversion circuit, including input power E, translation circuit inductance L₁, become Change circuit capacitance C₁, translation circuit output filter capacitor C₀；D₁For translation circuit electric capacity C₁Charging two pole Pipe, D₂For translation circuit booster diode, T is translation circuit switching tube, and R is translation circuit output loading etc. Effect resistance, U₀It it is translation circuit output voltage.

The positive pole of input power E and translation circuit inductance L₁One end, charging diode D₁Anode be connected, The negative pole of input power E and the emitter stage (being source electrode during field effect transistor) of translation circuit switch transistor T, conversion electricity Road output filter capacitor C₀Cold end, translation circuit output loading equivalent resistance R cold end be connected, Translation circuit inductance L₁The other end and translation circuit switch transistor T colelctor electrode (being drain electrode during field effect transistor), Translation circuit electric capacity C₁Cold end be connected, charging diode D₁Negative electrode and translation circuit electric capacity C₁'s Hot end, translation circuit booster diode D₂Anode be connected, translation circuit booster diode D₂Negative electrode With translation circuit output filter capacitor C₀Hot end, the high electricity of translation circuit output loading equivalent resistance R Position end is connected.

The operation principle of this boost conversion circuit, can control the cycle according to translation circuit switch transistor T at one In open, the working condition of circuit is analyzed under off state.For ease of analyzing circuit operation principle, the most right Some parameters of circuit carry out some explanations.Assuming that circuit work frequency is sufficiently high, during switching tube works, become Change circuit inductance L₁, translation circuit electric capacity C₁, translation circuit output filter capacitor C_oSufficiently large, then in conversion Contactor pipe T opens, in turn off process, electric current substantially constantization of voltage, inductance on electric capacity.

When translation circuit switch transistor T is opened, the current path in circuit has two, as in figure 2 it is shown, first Bar be from power supply E "+" → D₁→C₁→T→E“-”；Article 2 be from power supply E "+" → L₁→ T → E "-", electricity Road output voltage is kept by capacitance voltage.

According to KVL law, the 1st article of current path is had equation:

$E=L_1\frac{{\mathrm{di}}_{L1}}{dt}---\left(1\right)$

Under supply voltage effect, inductive current i_L1Increase,

To the 2nd article of current path, because impedance loop is the least, open period, electric capacity C at switching tube₁On quickly It is charged to supply voltage E；

U_C1=E (2)

When translation circuit switch transistor T turns off, the electric energy that inductance is stored will discharge, its current path such as figure Shown in 3, current path is: E "+" → L₁→C₁→D₂→C_o(R) → E "-", has equally:

$U_{C1}=E+U_{C1}+\left|L\frac{{\mathrm{di}}_{L1}}{dt}\right|=U_o---\left(3\right)$

Due to translation circuit inductance L₁Magnetic field energy to load transmission, inductive current will reduce, Therefore plus absolute value sign " | | " in formula (3)；

If the dutycycle of translation circuit switch transistor T isCan obtain from formula (1)-(3):

$\frac{U_o}{E}=\frac{2-\mathrm{\σ}}{1-\mathrm{\σ}}---\left(4\right)$

t_onFor translation circuit switch transistor T with switch periods T_sService time under working condition.

Owing to the dutycycle of switching tube is always less than 1, under same duty, the liter of Boost translation circuit Pressure ratio isCauseThe high-gain conversion of this circuit realiration input direct voltage.

The component parameters of high-gain DC boost conversion circuit selects:

(1) translation circuit inductance L₁

In translation circuit work process, translation circuit inductance L₁Being worth the biggest, input current is the most stable, but first The volume of part can increase, and the cost of circuit will increase.

If converter circuit needs the peak power changed to be P_Max, the maximum of converter circuit input current: I_Max=P_Max/ E, then inductive current parameter the most suitably leave certain surplus carry out select design.

I_L1e=I_Max；

(2) translation circuit switch transistor T

Owing to switching tube flows through inductive current when opening, switching tube rated current is according to inductive current maximum 1.2-1.5 times selects.When switching tube turns off, the voltage that pipe is born reaches supply voltage in theoryTimes, therefore, switching tube rated voltage is taken as its actual bear voltage 1.5-2.0 times.

T rated current I_Te=(1.2:1.5) I_Max；

T rated voltage

(3) diode

Diode D in conversion electric current₁、D₂Open in translation circuit switch transistor T, in turn off process, D₂Will Flow through inductive current, D₁The charging current of electric capacity, therefore, diode D will be flow through₂Rated current according to electricity 1.2-1.5 times of inducing current maximum selects, it is considered to capacitance charging current is relatively big, D₁Rated current suitably put Greatly, select according to 2.0-3.0 times.Voltage 1.5-2.0 times that rated voltage is born according to its reality selects.

D₂Rated current I_D2e=(1.2:1.5) I_Max；

D₁Rated current I_D1e=(2.0:3.0) I_Max；

D₁Rated voltage

D₂Rated voltage

(4) translation circuit electric capacity C₁, translation circuit output filter capacitor C_o

In translation circuit, capacity cell C₁、C₀The biggest, the holding capacity of circuit voltage is the strongest, but capacity is big Meaning that the volume of circuit increases, cost increases.Their rated voltage is according to its actual voltage that bears Choose for 1.5-2.0 times.

C₁Rated voltage U_C1e=(1.5:2.0) E；

C₀Rated voltage

If the pulsation scope control of circuit output voltage is at about the 1% of stationary value, changer output filter capacitor Choose according to the following formula.R is changer output loading equivalent resistance, T_sFor the switch controlled cycle.

$C_o\≥\frac{T_s}{5R}.$

Claims (6)

1. a high-gain DC boost conversion circuit, it is characterised in that: include input power E, conversion electricity Road inductance L₁, translation circuit electric capacity C₁, translation circuit output filter capacitor C₀, charging diode D₁, conversion Circuit booster diode D₂With translation circuit switch transistor T；The positive pole of described input power E and translation circuit electricity Sense L₁One end, charging diode D₁Anode be connected, the negative pole of described input power E is opened with translation circuit Close the emitter stage of pipe T, translation circuit output filter capacitor C₀Cold end, translation circuit output loading etc. The cold end of effect resistance R is connected；Described translation circuit inductance L₁The other end and translation circuit switching tube The colelctor electrode of T, translation circuit electric capacity C₁Cold end be connected, charging diode D₁Negative electrode with conversion electricity Road electric capacity C₁Hot end, translation circuit booster diode D₂Anode be connected, translation circuit boosts two poles Pipe D₂Negative electrode and translation circuit output filter capacitor C₀Hot end, translation circuit output loading equivalent electric The hot end of resistance R is connected.

High-gain DC boost conversion circuit the most according to claim 1, it is characterised in that: if circuit Output voltage pulsation scope control stationary value ± 1%, translation circuit output filter capacitor C₀Meet formula (I):

$C_o\≥\frac{T_s}{5R}---\left(I\right);$

Wherein: R is changer output loading equivalent resistance, T_sFor the switch controlled cycle.

High-gain DC boost conversion circuit the most according to claim 2, it is characterised in that: set conversion Device circuit needs the peak power changed to be P_Max, the pulsation of changer input current, less than the 10% of steady-state value, becomes The maximum of converter circuit input current: I_Max=P_Max/ E, described translation circuit inductance L₁Rated current I_L1e=I_Max, translation circuit inductance

High-gain DC boost conversion circuit the most according to claim 3, it is characterised in that: work as conversion Contactor pipe T opens, when turning off work:

Translation circuit switch transistor T rated current I_Te=(1.2:1.5) I_Max；

Translation circuit switch transistor T rated voltageWherein, translation circuit leaves The dutycycle closing pipe T is

High-gain DC boost conversion circuit the most according to claim 4, it is characterised in that: work as conversion Contactor pipe T opens, when turning off work:

Described translation circuit booster diode D₂Rated current I_D2e=(1.2:1.5) I_Max；

Described charging diode D₁Rated current I_D1e=(2.0:3.0) I_Max；

Described charging diode D₁Rated voltage

Described translation circuit booster diode D₂Rated voltage

High-gain DC boost conversion circuit the most according to claim 4, it is characterised in that: work as conversion Contactor pipe T opens, when turning off work:

Described translation circuit electric capacity C₁Rated voltage U_C1e=(1.5:2.0) E；

Described translation circuit output filter capacitor C₀Rated voltage