CN102801321A - High-efficiency wide voltage range bidirectional charging and discharging device control method - Google Patents

Abstract

The invention discloses a high-efficiency wide voltage range bidirectional charging and discharging device control method, which comprises the following steps: (1) adjusting the size of an output angle according to the output power or a set value or a feedback value of the current, wherein when the absolute value of the angle output is greater than the upper limit of the angle, an integrator starts positive integration output to be increased by D, in a similar way, when the absolute value of the angle output is smaller than the lower limit of the angle, the negative integration of the integrator is reduced by D; (2) determining to change the duty ratio on which side of an H bridge of a transformer according to the ratio of the voltage on direct current side of the primary and secondary sides, changing the secondary duty ratio D2 of the transformer, and limiting the duty ratio D2, otherwise changing a primary duty ratio D1 of the transformer, and limiting the duty ratio D1 in the range; and (3) combining steps (1) and (2), and limiting the duty ratio D obtained in step (1) in the range obtained in step (2). The two control modes are combined, the soft switching in the full-load range can be realized, the power can be output to the greatest degree, and the utilization rate of the device is improved.

Description

The two-way charge and discharge device control method of a kind of efficient wide-voltage range

Technical field:

The invention belongs to electricity field, relate to a kind of two-way charge and discharge device control method, the two-way charge and discharge device control method of especially a kind of efficient wide-voltage range.

Background technology:

Present employing Fig. 1 sort circuit mainly contains two kinds of control modes: pure phase shifting control (Only phase shift control) and phase shift add duty ratio control (Phase shift and duty ratio control) two kinds of control modes.

KHERALUWALA; M H has introduced the principle of pure phase shifting control (Only phase shift control) in detail at article " PERFORMANCE CHARACTERIZATION OF A HIGH-POWER DUAL ACTIVE BRIDGE DC-TO-DC-CONVERTER ": this method mainly is the break-make of control chart 1 former limit and secondary H bridge switch pipe; Form at the transformation two ends positive and negative square-wave signal (as shown in Figure 2, u ' ₂Be the waveform of secondary voltage equivalence to the former limit of transformer, U ₁Be the former limit of transformer dc voltage, U ' ₂For the voltage of transformer secondary dc voltage equivalence, have to the former limit of transformer

), through moving the phase place on both sides, realize the two-way flow of power.

Adopt power and the variation relation of angle of the control method transmission of pure phase shifting control to be:

But have only when the phase shift angle satisfies (0.2) and (0.3) simultaneously:

With

The time could realize the soft switch of both sides H bridge.That is to say; When the absolute value of phase shift angle was smaller, the efficient that adopts this control mode device was very low.

Tao, H mention in article " Transformer-coupled multiport ZVS bidirectional DC-DC converter with wdde input range " and have introduced phase shift and add duty ratio control (Phase shift and duty ratiocontrol).This control method mainly is the switching tube of control transformer side, realizes waveform as shown in Figure 3 (D is defined as duty ratio) in the transformer side:

Work as U ₁≤U ' ₂The time, the duty ratio of control transformer secondary makes

${\mathrm{<figure-callout\; id="2"\; label="D"\; filenames="339855DEST\_PATH\_HDA00002144877300022.png,DEST\_PATH\_HDA00001948769200013.png"\; state="\{\{state\}\}">D</figure-callout>}}_2=\frac{U_1}{{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="339855DEST\_PATH\_HDA00002144877300022.png,DEST\_PATH\_HDA00001948769200013.png"\; state="\{\{state\}\}">U</figure-callout>}}_2^{\&prime;}}---\left(0.4\right)$

As shown in Figure 4:

Work as U ₁＞U ' ₂The time, the duty ratio on the former limit of control transformer makes

${\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="DEST\_PATH\_HDA00001948769200013.png,DEST\_PATH\_HDA00001948769200031.png"\; state="\{\{state\}\}">D</figure-callout>}}_1=\frac{{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="339855DEST\_PATH\_HDA00002144877300022.png,DEST\_PATH\_HDA00001948769200013.png"\; state="\{\{state\}\}">U</figure-callout>}}_2^{\&prime;}}{U_1}---\left(0.5\right)$

Through such control method, can be so that under the situation of what phase shift angle in office, whole device can both be realized the soft switch in the full-load range.With U ₁≤U ' ₂Be example, the through-put power that obtains this control method is along with the situation of phase shift angle transformation is:

Contrast equation (0.1) and (0.6) can be known, can realize the soft switch in the full-load range though adopt phase shift to add duty ratio control, and the maximum power of transmission has but reduced.Adopt the maximum power of pure phase shifting control (Only phase shift control) transmission big, but be not that soft switch causes efficient low under the small-power situation; And adopting phase shift to add duty ratio control (Phase shift and duty ratiocontrol) though can realize the soft switch of full-load range, the maximum power of transmission but has restriction.Fig. 5 is an example with

, the situation that the power of the two kinds of control method transmission of having drawn changes along with phase shift angle φ.

Summary of the invention:

The objective of the invention is to overcome the shortcoming of above-mentioned prior art; Provide a kind of efficient wide-voltage range two-way charge and discharge device control method; Above these two kinds of control modes are combined; Can realize the soft switch in the full-load range, also power output has at utmost increased the utilance of device.

The objective of the invention is to solve through following technical scheme:

The two-way charge and discharge device control method of a kind of efficient wide-voltage range, according to following steps:

The size of (1) regulating the output angle according to the set-point and the value of feedback of power output or electric current; After angle output absolute value was greater than the angle upper limit

, integrator began the output of forward integration and increases D; In like manner; After the absolute value of angle output was less than angle lower limit , integrator negative sense integration reduced D;

(2) according to the ratio of former secondary dc voltage

Size decide the duty ratio that changes which side of transformer H bridge: if

Then change the duty ratio D of transformer secondary output ₂, simultaneously it is limited in

In like manner if

Then change the duty ratio D of primary ₁, it is limited in

In the scope;

(3) integrating step (1) and step (2) are in the resulting scope of duty ratio D conditioning step (2) that step (1) is obtained.

Said step (1) is: after angle output absolute value is greater than the angle upper limit

; Input integral device as a result, integrator begin the output of forward integration and increase D; After the absolute value of angle output is less than angle lower limit

; Input integral device as a result, integrator negative sense integration reduces D; Other situation integrator output initial values D.

Said step (2) is: calculating is also judged its size; If the scope that

then changes output duty cycle is at interval

in like manner, if

just

then the scope of output duty cycle is limited in the interval

.

Said step (3) is: the scope that integrating step (1) and step (2) obtain, limit final duty ratio output.If the scope that step (2) obtains is

Then with primary duty cycle D ₁=D, and with D ₁Be limited in the interval

If the scope that step (2) obtains is

Then make secondary duty ratio D ₂=D, and with D ₂Be limited in the interval

The inventive method has been used in the 12kVA charge and discharge device, and is very big if adopt pure phase shifting control then to install circulation in this device, even can't under low-pressure state, discharge and recharge; But if just adopt phase shift to add duty ratio control, little electric current discharges and recharges can be more steady, but can't export big electric current.Adopt the inventive method, can realize that high efficiency the discharging and recharging also of little electric current can realize discharging and recharging under the current state, and charging process is steady.

Description of drawings:

Fig. 1 discharges and recharges main circuit topology figure for bidirectional, dc DCDC;

Fig. 2 is the former secondary voltage oscillogram of pure phase shifting control transformer;

Fig. 3 is duty ratio control waveform figure;

Fig. 4 controls former secondary voltage oscillogram for phase shift adds duty ratio;

Fig. 5 is that two kinds of control mode through-put powers are along with phase shift angle situation of change figure;

Fig. 6 is a practical implementation block diagram of the present invention;

Fig. 7 encircles control logic figure for the present invention stagnates;

Fig. 8 is a flow chart of the present invention;

Fig. 9 is a charging current oscillogram under the 7V electric pressure.

Wherein: N ₁Be the primary number of turn; N ₂Be the transformer secondary output number of turn; Be transformer voltage ratio; L is the total leakage inductance of primary; F is the operating frequency of switching tube; ω is a switching tube operating angle frequency, and ω=2 π f are arranged; U ₁Be transformer primary direct voltage amplitude; U ₂Be transformer secondary direct voltage amplitude; U' ₁For the amplitude of transformer primary direct voltage equivalence, have to primary side

U ' ₂For the amplitude of transformer secondary direct voltage equivalence, have to primary side

T _sSwitch periods for switching tube; D is a duty ratio, and being defined as voltage waveform is positive time and the ratio of 1/2 switch periods, wherein 0＜D≤1; D ₁Be the primary voltage duty cycle; D ₂Be the transformer-secondary voltage duty ratio;

Be the phase shift angle, former secondary voltage waveform phase is poor; For adopting the phase shift angle lower threshold of this method;

For adopting the phase shift angle upper limit threshold of this method; P is the power of device output; P _BaseBe reference power, be defined as

P _uPerunit value for the device through-put power is defined as

Embodiment:

Below in conjunction with accompanying drawing the present invention is done and to describe in further detail:

Referring to Fig. 6, Fig. 7, Fig. 8 and Fig. 9, can see that from Fig. 6 several core of the present invention is respectively: ask absolute value, the chain rate that stagnates and integrator control.Can find out from formula (0.6); In the time of phase shift angle

; Adopt phase shift to add the duty specific energy and realize soft switch, adopt when phase shift angle

time pure phase shifting control and phase shift to add duty ratio and control and all can realize soft switch.Defines two angles

and

making

The stagnant ring control module of Fig. 6, its internal logic control block diagram is as shown in Figure 7:

When output phase shift angle

After, integrator Integrator begins the forward integration; When output phase shift angle

The time, integrator Integrator begins the negative sense integration, and the export-restriction of integrator is existed

When the phase shift angle

Absolute value less than The time, guaranteed that duty ratio output just has been controlled at

Have only when the output angle After, D ₂Beginning slowly increases (being up to 1); Equally, when the user reduces the instruction of power output (perhaps electric current), also have only

After, the duty Bizet can slowly change to

Whole like this process has promptly realized soft switch, has also increased the upper limit of through-put power.The implementing procedure figure of entire method is as shown in Figure 8:

Of the present invention can being used in the two-way systems that discharge and recharge of various needs such as photovoltaic generation, wind power generation, energy storage device PCS (Power Conversion System), fuel cell, electric automobile.(the charging/discharging voltage scope is [V with my company's one cover charge and discharge device ₁, V ₂], and V ₁＜V ₂) be example, implementation process of the present invention is described:

At first, through a three-phase PFC (power factor correction) line voltage is stabilized in 650V.

Then, transformer voltage ratio is designed to 650:V ₂, like this at V ₂Simple phase shift just can realize soft switch in the gamut under the electric pressure, and is not V at voltage ₂The time, just can just can realize through the duty ratio that only changes elementary H bridge FR in soft switch.

Secondly, through voltage Hall sampling secondary-side voltage, when detecting voltage less than V ₂The time, the H bridge duty ratio that can adopt the inventive method to regulate primary realizes FR soft switch.

At last, if power and current-order change greatly, then also can adopt this to realize that pure phase shifting control and phase shift add the flexible switching of duty ratio control.

Channel oscilloscope one is V among Fig. 9 ₁The waveform of following charging current (electric current during duty ratio begin to increase) to 150A.

The above only is preferred embodiment of the present invention, is not the present invention is done any pro forma restriction; Though the present invention discloses as above with preferred embodiment; Yet be not in order to limiting the present invention, anyly be familiar with the professional and technical personnel, in not breaking away from technical scheme scope of the present invention; When the method for above-mentioned announcement capable of using and technology contents are made a little change or be modified to the equivalent embodiment of equivalent variations; In every case be the content that does not break away from technical scheme of the present invention, to any simple modification, equivalent variations and modification that above embodiment did, still belong in the scope of technical scheme of the present invention according to technical spirit of the present invention.

Claims (4)

1. the two-way charge and discharge device control method of efficient wide-voltage range is characterized in that, according to following steps:

The size of (1) regulating the output angle according to the set-point and the value of feedback of power output or electric current; After angle output absolute value was greater than the angle upper limit

, integrator began the output of forward integration and increases D; In like manner; After the absolute value of angle output was less than angle lower limit

, integrator negative sense integration reduced D;

(2) according to the ratio of former secondary dc voltage

Size decide the duty ratio that changes which side of transformer H bridge: if Then change the duty ratio D of transformer secondary output ₂, simultaneously it is limited in

In like manner if

Then change the duty ratio D of primary ₁, it is limited in

In the scope;

(3) integrating step (1) and step (2), the duty ratio D that step (1) is obtained is limited in the resulting scope of step (2).

2. the two-way charge and discharge device control method of a kind of according to claim 1 efficient wide-voltage range is characterized in that:

Said step (1) is: after angle output absolute value is greater than the angle upper limit ; Input integral device as a result, integrator begin the output of forward integration and increase D; After the absolute value of angle output is less than angle lower limit ; Input integral device as a result, integrator negative sense integration reduces D; After angle output absolute value equals the angle upper limit

; Input integral device as a result, integrator output initial value D.

3. the two-way charge and discharge device control method of a kind of according to claim 1 efficient wide-voltage range is characterized in that:

Said step (2) is: calculating

is also judged its size; If the scope that

then changes output duty cycle is at interval

in like manner, if

just

then the scope of output duty cycle is limited in the interval

.

4. the two-way charge and discharge device control method of a kind of according to claim 1 efficient wide-voltage range is characterized in that:

Said step (3) is: the scope that integrating step (1) and step (2) obtain, limit final duty ratio output; If the scope that step (2) obtains is Then with primary duty cycle D ₁=D, and with D ₁Be limited in the interval

If the scope that step (2) obtains is

Then make secondary duty ratio D ₂=D, and with D ₂Be limited in the interval

Images