CN102832814B - Method for controlling hysteresis with voltage feedforward quickly - Google Patents
Method for controlling hysteresis with voltage feedforward quickly Download PDFInfo
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- CN102832814B CN102832814B CN201210330523.3A CN201210330523A CN102832814B CN 102832814 B CN102832814 B CN 102832814B CN 201210330523 A CN201210330523 A CN 201210330523A CN 102832814 B CN102832814 B CN 102832814B
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Abstract
The invention relates to a method for controlling hysteresis with voltage feedforward quickly. A feedback circuit for traditional PWM voltage control is replaced by a hysteresis comparator and a feedback bypass, an input voltage is connected with a charging capacitor through a feedforward adjustment resistor, and the input voltage is also connected with a reference voltage through an upper and lower limit threshold adjustment resistor. An output voltage is connected with the charging capacitor through the feedforward adjustment resistor. The change of the input voltage and the output voltage lead to the change of the voltage on two ends of the charging capacitor. According to the method, no operational amplifier and triangular carrier circuit are used, the precise control of the output voltage is realized, only one hysteresis comparator is used so that the number of control components is reduced greatly, no error amplifier is used, no feedback phase delay is caused, the output voltage can be controlled at the minimum limit when the load and the input voltage change so that the original output voltage level can be restored quickly, and the requirements for high-speed transient response, small size, low cost and high-efficiency are met when the input voltage and the output load change.
Description
Technical field
The present invention relates to a kind of Switching Power Supply control technology, particularly a kind of quick hysteresis control method thereof with electric voltage feed forward.
Background technology
Along with the develop rapidly of semiconductor and information technology, be that Switching Power Supply must meet following technical need as the DC-to-DC chopper of their power-supply management systems: (1) output voltage is low; (2) output voltage precision is high; (3) output current is large; (4), when input power and output loading transition, the transient overshoot of output voltage is little.Stable state and the dynamic characteristic of above demand to Switching Power Supply proposed higher requirement, and the control method of Switching Power Supply has been proposed to new challenge.Wherein, traditional PWM voltage control method is because it meets the basic demand of stability and control precision, and is widely used in Switching Power Supply.But, this control method only relates in the time that output variable variation causes that load voltage changes to be controlled, in the time that input voltage and load are undergone mutation, the disturbance achieve effective control causing when input variable variation, also have the time delay that the compensating circuit of voltage error amplifier in control circuit brings to lag behind, not only cause its transient response slow, reduce its dynamic characteristic, and in control circuit, use operational amplifier and triangular carrier to produce circuit and other compensating circuit, these easily cause the manufacturing cost of Switching Power Supply to rise, be difficult to realize miniaturization and lightweight.And the compensating circuit of voltage error amplifier is comparatively complicated in the time of design and debugging.These problems have been brought a lot of difficulties to designer above, and have extended the design cycle, consumed a large amount of manpower and materials.
Summary of the invention
The present invention be directed to traditional PWM voltage control method and be difficult to meet the response of input and output High-speed transient, miniaturization, lightweight, low cost, high efficiency problem, a kind of quick hysteresis control method thereof with electric voltage feed forward has been proposed, propose in the time that input and output amount changes, there is the novel stagnant ring control mode of fast transient response characteristic, effectively improve the dynamic characteristic of control circuit, there is good stable state and dynamic characteristic.
Technical scheme of the present invention is: a kind of quick hysteresis control method thereof with electric voltage feed forward, keeping on the basis of former PWM voltage switch partial circuit, changing original PWM voltage control circuit feedback fraction and be: output voltage is through feedback adjusting resistance and the charging capacitor ground connection of series connection; Input voltage, by the output of input MOS switching tube, connects feedforward adjusting resistance and charging capacitor ground connection; Input voltage is by input MOS switching tube, connects ground connection after two bound threshold values size adjusting resistances of series connection and reference voltage; Charging capacitor voltage termination hysteresis comparator inverting input, two bound threshold values size adjusting resistance intermediate points connect hysteresis comparator in-phase input end, and hysteresis comparator output connects input MOS switching tube grid through overdrive circuit; Obtain output voltage
wherein D
ofor duty ratio D
o=(V
l-V
oL)/(V
oH-V
oL), K
cfor feedback oscillator K
c=R/ (R
fv
oH-R
fv
oL), V
lfor hysteresis comparator high level threshold voltage, V
oL, V
oHbe respectively hysteresis comparator output low level, high level voltage, r is decompression DC transducer equivalent internal resistance, and Ro is load, and R is feedforward adjusting resistance; Rf is feedback adjusting resistance.
Described input MOS switching tube output to feedforward adjusting resistance centre can additional proportion or proportional integral link.
The centre of two bound threshold values size adjusting resistances of described input MOS switching tube output can additional proportion or proportional integral link.
Described input voltage is through the output of input MOS switching tube source electrode, connects after two bound threshold values size adjusting resistances of series connection and reference voltage in ground connection.
Beneficial effect of the present invention is: the present invention, with the quick hysteresis control method thereof of electric voltage feed forward, without operational amplifier and triangular carrier circuit, has realized the accurate control of output voltage; Only need a hysteresis comparator, control circuit device greatly reduces, and control circuit topology is simple; There is no use error amplifier, do not have feedback phase to postpone, do not need phase compensating circuit completely.Meanwhile, the stability of control circuit is greatly improved; When load change and input voltage variation, output voltage all can be controlled in Min. down to the fast former output voltage level of quick-recovery of energy, and output voltage overshoot and adjusting time are all minimum, and then have good adjusting and High-speed transient response characteristic; Compared with traditional PWM voltage control method, High-speed transient response in the time that input voltage and output loading change, small-sized, low cost, high efficiency requirement are met.
Brief description of the drawings
Fig. 1 is traditional PWM voltage control method circuit diagram;
Fig. 2 is novel hysteresis control method thereof embodiment mono-circuit diagram of the present invention with electric voltage feed forward;
Fig. 3 is novel hysteresis control method thereof embodiment bis-circuit diagrams of the present invention with electric voltage feed forward;
Fig. 4 is the schematic diagram of movements of the present invention with the novel hysteresis control method thereof embodiment mono-and two of electric voltage feed forward;
Fig. 5 is that the present invention combines a circuit diagram with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Fig. 6 is that the present invention combines two circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Fig. 7 is that the present invention combines four circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Fig. 8 is that the present invention combines six circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Fig. 9 is that the present invention combines seven circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Figure 10 is that the present invention combines eight circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Figure 11 is that the present invention combines nine circuit diagrams with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Figure 12 is that the present invention combines seven circuit output response curves with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Figure 13 is that the present invention combines nine circuit output response curves with the novel hysteresis control method thereof embodiment of electric voltage feed forward;
Figure 14 is the load current Io conventional P WM voltage control transient response curve figure while falling a times that jumps;
Figure 15 is that load current Io of the present invention jumps while falling one times with the new type of control method embodiment mono-transient state response curve of electric voltage feed forward;
Figure 16 is that load current Io of the present invention jumps while falling one times with the new type of control method embodiment bis-transient response curve figure of electric voltage feed forward;
Figure 17 is load current Io conventional P WM voltage control transient response curve figure while rising to a times;
Figure 18 is load current Io of the present invention new type of control method embodiment mono-transient state response curve with electric voltage feed forward while rising to a times;
Figure 19 is load current Io of the present invention new type of control method embodiment bis-transient response curve figure with electric voltage feed forward while rising to a times;
Figure 20 is the input voltage conventional P WM voltage control transient response curve figure while falling 40% that jumps;
Figure 21 is that input voltage of the present invention jumps while falling 40% with the new type of control method embodiment mono-transient state response curve of electric voltage feed forward;
Figure 22 is that input voltage of the present invention jumps while falling 40% with the new type of control method embodiment bis-transient response curve figure of electric voltage feed forward;
Figure 23 is input voltage conventional P WM voltage control transient response curve figure while rising to 40%;
Figure 24 is input voltage of the present invention new type of control method embodiment mono-transient state response curve with electric voltage feed forward while rising to 40%;
Figure 25 is input voltage of the present invention new type of control method embodiment bis-transient response curve figure with electric voltage feed forward while rising to 40%.
Embodiment
For the shortcoming of traditional control method, we have proposed in the time that input and output amount changes, and have the novel stagnant ring control mode of fast transient response characteristic.By designing different output voltages and the feedback branch of input voltage, simultaneously in conjunction with the work characteristics of hysteresis comparator, effectively regulate the pulse duration of control signal, realize the stable of output voltage.Because this control method only needs a hysteresis comparator and feedback factor regulating resistance, the number of devices of control circuit greatly reduces, and cost and volume have all obtained larger improvement.And, owing to there is no use error amplifier, in having eliminated the phase delay problem that compensating circuit brings, effectively improve the dynamic characteristic of control circuit.Finally by theory analysis and emulation with the basis of traditional control method contrast on, verified that this control method, in the time of load change and input voltage variation, has good stable state and dynamic characteristic.
Traditional PWM voltage control method circuit diagram as shown in Figure 1, in figure, Vi is input voltage; MOS1, MOS2 is full-controlled switch pipe MOSFET or IGBT; L1 is filter inductance; Co is filter capacitor; Rc is equivalent series resistance; Rc1, Rc2, Rc3, Rc4 is resistance; Ro is load; Vo is output voltage; Vrc is reference voltage; Vtri is carrier voltage.Traditional output voltage
(1), wherein D is duty ratio, and r is decompression DC transducer equivalent internal resistance.
With novel hysteresis control method thereof embodiment mono-and embodiment bis-circuit diagrams of electric voltage feed forward, in figure, L is filter inductance as shown in Figure 2,3; Vu is hysteresis comparator; R1, R2 are respectively bound threshold values size adjusting resistance; R is feedforward adjusting resistance; Rf is feedback adjusting resistance; V1 is reference voltage.
Switch periods T computing formula:
wherein
(2), V
l, V
hfor hysteresis comparator threshold voltage (low level, high level), V
cfor open loop control voltage, equal output voltage V at this
o,
Hysteresis comparator threshold values high level voltage
Level voltage at the bottom of hysteresis comparator threshold values
Output voltage
(3); Wherein Do is duty ratio D
o=(V
l-V
oL)/(V
oH-V
oL), only in the time of Vc=VL, D=Do; Kc is feedback oscillator K
c=R/ (R
fv
oH-R
fv
oL), wherein V
oL, V
oHfor hysteresis comparator output voltage (low level, high level), Fig. 4 is the schematic diagram of movements with the novel hysteresis control method thereof embodiment mono-and two of electric voltage feed forward.
According to a indicating in Fig. 2 and Fig. 3, b, u and 1,2 can show that 9 groups connect combination, are respectively the first combination as shown in Figure 5: 1 connects a, and 2 connect b; Second combines as shown in Figure 6: 1 connects u, and 2 connect b; The 3rd combines as shown in Figure 2: 1 connects b, and 2 connect b; The 4th combines as shown in Figure 7: 1 connects u, and 2 connect u; The 5th combines as shown in Figure 3: 1 connects b, and 2 connect u; The 6th combines as shown in Figure 8: 1 connects a, and 2 connect u; The 7th combines as shown in Figure 9: 1 connects b, and 2 connect a; The 8th combines as shown in figure 10: 1 connects a, and 2 connect a; The 9th combines as shown in figure 11: 1 connects u, and 2 connect a.Wherein third and fourth, five, seven and nine combinations are all feasible, the existing document of the 4th combination relates to.Seven, nine be combined as non-stagnant ring control, control output effect undesirable.Seven, nine array output effects are exported response curve as shown in Figure 12 and Figure 13, and wherein input voltage is 5V, and load is 0.6 Ω, voltage-target 4V.
In these combinations in every kind of combination 2 can additional proportion between being connected or proportional integral link control.For example the 3rd combination, just can 1 and b between additional proportion or proportional integral link, 2 and b between additional proportion or proportional integral link, the parameter of the ratio adding or proportional integral link can regulate according to circuit.
Quick hysteresis control method thereof with electric voltage feed forward is made up of hysteresis comparator Vu and feedback bypass.Input voltage is connected with capacitor C through resistance R, and input voltage is connected with voltage V1 with R1 through resistance R 2 simultaneously.Output voltage V o is connected with capacitor C through resistance R _ f.Change by input and output voltage causes the change in voltage at capacitor C two ends.
Based on the principle of capacitor C charge balance, realize the control discharging and recharging and then the adjusting that realizes comparator output duty cycle and cycle time.The variation essence of capacitor C both end voltage is the charge-discharge principle of capacitor C.Must depend on the threshold voltage V of hysteresis comparator according to time of capacitor charge and discharge and speed
hand V
ldifference and the reason of this two aspect of electric current of flow through resistance R _ f and resistance R, in the design, by input voltage is connected with capacitor C through resistance R, output voltage is connected with capacitor C through resistance R _ f, and then jointly realize the control to capacitor C charge-discharge velocity, input voltage is connected with reference voltage V1 with R1 through resistance R 2 simultaneously.Because threshold voltage
Can make threshold voltage V by input voltage as seen
hchange, by voltage V
1make V
hand V
lchange.In the visible new type of control method proposing, for two factors that affect the variation of electric capacity both end voltage, be achieved by the quick dynamic adjustments and the response that utilize input and output.Detected capacitance voltage Vf has determined shutoff and the ON time of power switch pipe.In a switch periods, the rising of voltage Vf and descending slope and input voltage and output voltage and threshold voltage are relevant, and therefore, the size of each switch periods can change because of the variation of input voltage and output voltage.Compare with traditional PWM voltage control method, in the time of input voltage and load current change, input and output have been realized the compound control of electric voltage feed forward and feedback by common adjusting, the transient response time with output voltage is short, overshoot is little, fluctuates little, and stability is high, the feature that error is controlled, thus meet dynamic and static performance index preferably.Difference between can finding out by emulation, as shown in Figure 14～16, load current Io jumps while falling one times, conventional P WM voltage control, new type of control method embodiment mono-, new type of control method embodiment mono-transient state response curve, comprise load current IR, input voltage Vi and output voltage V o curve chart.When as shown in Figure 17～19, load current Io rises to one times, conventional P WM voltage control, new type of control method embodiment mono-, new type of control method embodiment mono-transient state response curve.As shown in Figure 20～22, input voltage jumps while falling 40%, conventional P WM voltage control, new type of control method embodiment mono-, new type of control method embodiment mono-transient state response curve.When as shown in Figure 23～25, input voltage rises to 40%, conventional P WM voltage control, new type of control method embodiment mono-, new type of control method embodiment mono-transient state response curve.
The comparison of new type of control method embodiment mono-and embodiment bis-:
When load variations, no matter be that load increases or reduces, embodiment mono-is less than the overshoot of embodiment bis-and adjusting time, so in load variations occasion frequently, embodiment mono-is better than embodiment bis-.
When input voltage increases, embodiment bis-is larger than the overshoot of embodiment mono-, but the adjusting time is little, and the Voltage Stability Level of final embodiment bis-is better than embodiment mono-;
When input voltage declines, the overshoot of embodiment mono-and adjusting time are all less than embodiment bis-, and finally both voltage levvls are all stabilized in same numerical value.Because embodiment bis-steady state voltage levels are better than embodiment mono-, and the overshoot of two kinds of methods and adjusting time quite approach and can meet transient response fast completely, should select embodiment bis-so change occasion frequently for input voltage.
In sum, select when occasion frequently and control embodiment mono-in load variations, in the time that input voltage changes frequently occasion, select embodiment bis-.Entirety, the difference of embodiment mono-and embodiment bis-is little.
Claims (4)
1. the quick hysteresis control method thereof with electric voltage feed forward, it is characterized in that, keeping on the basis of former PWM voltage switch partial circuit, changing original PWM voltage control circuit feedback fraction and be: output voltage is through feedback adjusting resistance and the charging capacitor ground connection of series connection; Input voltage, by the output of input MOS switching tube, connects feedforward adjusting resistance and charging capacitor ground connection; Input voltage is by input MOS switching tube, connects ground connection after two bound threshold values size adjusting resistances of series connection and reference voltage; Charging capacitor voltage termination hysteresis comparator inverting input, two bound threshold values size adjusting resistance intermediate points connect hysteresis comparator in-phase input end, and hysteresis comparator output connects input MOS switching tube grid through overdrive circuit; Obtain output voltage
wherein Vi is input voltage, D
ofor duty ratio D
o=(V
l-V
oL)/(V
oH-V
oL), K
cfor feedback oscillator K
c=R/ (R
fv
oH-R
fv
oL), V
lfor hysteresis comparator low level threshold voltage, V
oL, V
oHbe respectively hysteresis comparator output low level, high level voltage, r is decompression DC transducer equivalent internal resistance, and Ro is load, and R is feedforward adjusting resistance; Rf is feedback adjusting resistance.
2. according to claim 1 with the quick hysteresis control method thereof of electric voltage feed forward, it is characterized in that, described input MOS switching tube output to feedforward adjusting resistance centre can additional proportion or proportional integral link.
3. according to claim 1 with the quick hysteresis control method thereof of electric voltage feed forward, it is characterized in that, the centre of two bound threshold values size adjusting resistances of described input MOS switching tube output can additional proportion or proportional integral link.
4. according to claim 1 with the quick hysteresis control method thereof of electric voltage feed forward, it is characterized in that, described input voltage is through the output of input MOS switching tube source electrode, connects after two bound threshold values size adjusting resistances of series connection and reference voltage in ground connection.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210330523.3A CN102832814B (en) | 2012-09-10 | 2012-09-10 | Method for controlling hysteresis with voltage feedforward quickly |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210330523.3A CN102832814B (en) | 2012-09-10 | 2012-09-10 | Method for controlling hysteresis with voltage feedforward quickly |
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| CN102832814B true CN102832814B (en) | 2014-11-26 |
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| CN108432114A (en) * | 2015-10-27 | 2018-08-21 | 集成装置技术公司 | The system and method for carrying out wireless power transmission using the electric power converter with bypass mode |
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| CN103346663A (en) * | 2013-07-16 | 2013-10-09 | 上海电力学院 | Hysteresis control method of Boost convertor |
| CN103546034B (en) * | 2013-10-30 | 2016-02-03 | 上海电力学院 | A kind of compounding feedforward control type Hysteresis control system |
| CN103701321B (en) * | 2014-01-03 | 2015-12-30 | 东南大学 | A kind of fast transient response buck synchronous rectified DC-DC converter |
| CN103762831B (en) * | 2014-02-20 | 2017-01-25 | 上海电力学院 | PWM voltage priority control circuit |
| CN104953832B (en) * | 2015-06-16 | 2017-11-07 | 南京矽力杰半导体技术有限公司 | The Buck step-down circuits and its control method controlled based on input voltage feed forward |
| CN105739307B (en) * | 2016-01-29 | 2018-08-07 | 浙江大学 | The stagnant ring compensation device of proportional pressure-reducing valve based on adaptive robust control and method |
| CN109088541A (en) * | 2018-09-29 | 2018-12-25 | 天津大学 | A kind of switched-mode power supply of the quasi- fixed-frequency control of voltage hysteresis |
| CN112332820A (en) * | 2020-11-16 | 2021-02-05 | 合肥科威尔电源系统股份有限公司 | Control circuit for testing power supply discharge resistance and control method thereof |
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| CN101145732A (en) * | 2006-09-11 | 2008-03-19 | 麦奎尔有限公司 | Ripple generation in buck regulator using fixed on-time control |
| US7459893B2 (en) * | 2006-04-20 | 2008-12-02 | Mark E Jacobs | Optimal feedback control of switch-mode power converters |
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|---|---|---|---|---|
| US6147478A (en) * | 1999-09-17 | 2000-11-14 | Texas Instruments Incorporated | Hysteretic regulator and control method having switching frequency independent from output filter |
| US7459893B2 (en) * | 2006-04-20 | 2008-12-02 | Mark E Jacobs | Optimal feedback control of switch-mode power converters |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108432114A (en) * | 2015-10-27 | 2018-08-21 | 集成装置技术公司 | The system and method for carrying out wireless power transmission using the electric power converter with bypass mode |
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