TWI765547B

TWI765547B - An isolated conversion device with magnetic bias balance control and method of magnetic bias balance control the same

Info

Publication number: TWI765547B
Application number: TW110103203A
Authority: TW
Inventors: 李志賢; 謝奕平; 林鴻杰; 黃弘宇; 潘巧茵
Original assignee: 台達電子工業股份有限公司
Priority date: 2021-01-28
Filing date: 2021-01-28
Publication date: 2022-05-21
Also published as: TW202230956A

Abstract

An isolated conversion device with magnetic bias balance control, including an isolated converter, a controller and a magnetic bias balance control circuit. The isolated converter includes a transformer, and a primary side of the transformer includes a primary side winding and at least one switch bridge arm. The controller is coupled to at least one switch bridge arm, and provides a pulse width modulation signal group to control the at least one switch bridge arm. The magnetic bias balance control circuit is coupled to both ends of the primary winding and the controller, and provide a compensation voltage to the controller according to the average voltage of a winding voltage at both ends of the primary winding. The controller adjusts a duty cycle of the pulse width modulation signal group according to the compensation voltage to correct the magnetic bias.

Description

具有磁偏平衡控制之隔離型轉換裝置及其磁偏平衡控制方法 Isolated conversion device with magnetic bias balance control and magnetic bias balance control method

本發明係有關一種轉換裝置之磁偏平衡控制方法，尤指一種隔離型轉換裝置之磁偏平衡控制方法。 The present invention relates to a magnetic bias balance control method of a conversion device, in particular to a magnetic bias balance control method of an isolated conversion device.

圖1A為習知的全橋相移轉換器電路架構。由於硬體線路差異的不同或控制開關Q1~Q4的訊號有出現開關責任週期不同時，造成變壓器12正負跨壓平均不為零，導致磁化電流產生平均量不為零的現象(簡稱磁偏)，最終導致變壓器12的激磁電感飽和，電感值急速減少，造成轉換器初級側電流過大的風險。 FIG. 1A is a circuit structure of a conventional full-bridge phase-shift converter. Due to the difference of the hardware circuit or the different switching duty cycles of the signals controlling the switches Q1~Q4, the average positive and negative voltage across the transformer 12 is not zero, resulting in the phenomenon that the average amount of the magnetizing current is not zero (referred to as magnetic bias) , which eventually leads to saturation of the magnetizing inductance of the transformer 12, and the inductance value decreases rapidly, resulting in the risk of excessive current on the primary side of the converter.

因此，在習知技術中，通常於變壓器12的初級側串接電容C來平衡變壓器12正負半週跨壓而避免磁偏現象的產生。但是，此控制方式則需於電路中增加一電容C，相對地會增加電路成本以及電路體積。另一種常見的解決方式如圖1B所示，在此全橋電路加入電流感測器CT並使用電流峰值控制法，此控制方法會使得磁偏的半週因電流較高而提早關閉開關責任週期，因此可以降低磁偏一方的電壓與時間乘積，以達到平衡磁偏的效果。但是，此控制方式需於電路中增加一組電流感測器CT，同樣地也會增加電路成本以及電路體積。 Therefore, in the prior art, a capacitor C is usually connected in series with the primary side of the transformer 12 to balance the positive and negative half-cycle voltages of the transformer 12 to avoid the magnetic bias phenomenon. However, this control method needs to add a capacitor C to the circuit, which relatively increases the circuit cost and circuit volume. Another common solution is shown in Figure 1B, where a current sensor CT is added to the full-bridge circuit and a current peak control method is used. This control method will make the half cycle of the magnetic bias turn off the switching duty cycle earlier due to the high current. , so you can Reduce the product of voltage and time on one side of the magnetic bias to achieve the effect of balancing the magnetic bias. However, this control method needs to add a set of current sensors CT in the circuit, which also increases the circuit cost and circuit volume.

所以，如何設計出一種具有磁偏平衡控制之隔離型轉換裝置及其磁偏平衡控制方法，無需使用增加電流感測器的控制方式，也無需增加隔離電容而平衡磁偏，乃為本案創作人所欲行研究的一大課題。 Therefore, how to design an isolated conversion device with magnetic bias balance control and its magnetic bias balance control method, without using the control method of adding current sensors, and without adding isolation capacitors to balance the magnetic bias, is the creator of this project. A major topic for research.

為了解決上述問題，本發明係提供一種具有磁偏平衡控制之隔離型轉換裝置，以克服習知技術的問題。因此，本發明隔離型轉換裝置包括：隔離型轉換器，包括變壓器，變壓器的初級側包括初級側繞組與至少一開關橋臂。控制器，耦接至少一開關橋臂，且提供脈寬調變訊號組控制至少一開關橋臂。及磁偏平衡電路，耦接初級側繞組的兩端與控制器，且根據初級側繞組兩端的繞組電壓的電壓平均值而提供補償電壓至控制器；其中控制器根據補償電壓調整脈寬調變訊號組的佔空比。 In order to solve the above problems, the present invention provides an isolated conversion device with magnetic bias balance control to overcome the problems of the prior art. Therefore, the isolated converter device of the present invention includes: an isolated converter, including a transformer, and the primary side of the transformer includes a primary side winding and at least one switch bridge arm. The controller is coupled to at least one switch bridge arm, and provides a pulse width modulation signal group to control the at least one switch bridge arm. and a magnetic bias balance circuit, which is coupled to both ends of the primary side winding and the controller, and provides a compensation voltage to the controller according to the voltage average value of the winding voltages at both ends of the primary side winding; wherein the controller adjusts the pulse width modulation according to the compensation voltage The duty cycle of the signal group.

為了解決上述問題，本發明係提供一種隔離型轉換裝置之磁偏平衡控制方法，以克服習知技術的問題。因此，隔離型轉換裝置包括隔離型轉換器，且隔離型轉換器包括變壓器與耦接變壓器初級側的至少一開關橋臂，本發明磁偏平衡控制方法包括下列步驟：(a)提供脈寬調變訊號組控制至少一開關橋臂切換而使隔離型轉換器將輸入電壓轉換為輸出電壓。(b)根據變壓器的初級側繞組兩端的繞組電壓而提供對應變壓器的磁偏的補償電壓。及(c)根據補償電壓調整脈寬調變訊號組的佔空比，以修正磁偏。 In order to solve the above problems, the present invention provides a magnetic bias balance control method of an isolated converter device to overcome the problems of the prior art. Therefore, the isolated converter device includes an isolated converter, and the isolated converter includes a transformer and at least one switch arm coupled to the primary side of the transformer, the magnetic bias balance control method of the present invention includes the following steps: (a) providing a pulse width modulation The signal-changing group controls at least one switch bridge arm to switch so that the isolated converter converts the input voltage into the output voltage. (b) Providing a compensation voltage corresponding to the magnetic bias of the transformer according to the winding voltage across the primary side winding of the transformer. and (c) adjusting the duty cycle of the PWM signal group according to the compensation voltage to correct the magnetic bias.

本發明之主要目的及功效在於，利用取樣變壓器初級側繞組兩端的繞組電壓，經由濾波線路取其平均值，再透過控制器將其控制為0而修正磁偏，藉此可無需使用增加電流感測器的控制方式，也無需增加隔離電容，進而達到降低電路體積及電路成本之功效。 The main purpose and effect of the present invention is to use the winding voltage at both ends of the primary side winding of the sampling transformer to obtain the average value through the filter circuit, and then control it to 0 through the controller to correct the magnetic bias, thereby eliminating the need to increase the current inductance. The control method of the tester does not need to increase the isolation capacitor, thereby achieving the effect of reducing the circuit volume and circuit cost.

為了能更進一步瞭解本發明為達成預定目的所採取之技術、手段及功效，請參閱以下有關本發明之詳細說明與附圖，相信本發明之目的、特徵與特點，當可由此得一深入且具體之瞭解，然而所附圖式僅提供參考與說明用，並非用來對本發明加以限制者。 In order to further understand the technology, means and effect adopted by the present invention to achieve the predetermined purpose, please refer to the following detailed description and accompanying drawings of the present invention. For specific understanding, however, the accompanying drawings are only provided for reference and description, and are not intended to limit the present invention.

1、1’:隔離型轉換裝置 1, 1': Isolated conversion device

1A:輸入端 1A: input terminal

1B:輸出端 1B: output terminal

10、10’:隔離型轉換器 10, 10': Isolated converter

12:變壓器 12: Transformer

122:初級側繞組 122: Primary side winding

124:次級側繞組 124: Secondary side winding

14:開關橋臂 14: switch bridge arm

142:第一橋臂 142: The first bridge arm

Q1:第一開關 Q1: The first switch

Q2:第二開關 Q2: Second switch

144:第二橋臂 144: Second bridge arm

Q3:第三開關 Q3: The third switch

Q4:第四開關 Q4: Fourth switch

146:電容組 146: Capacitor bank

C1:第一電容 C1: first capacitor

C2:第二電容 C2: second capacitor

16:次級側電路 16: Secondary side circuit

20:控制器 20: Controller

22:第一運算電路 22: The first operation circuit

24:電壓控制器 24: Voltage Controller

26:脈寬調變電路 26: Pulse width modulation circuit

30:磁偏平衡電路 30: Magnetic bias balance circuit

32:取樣電路 32: Sampling circuit

322:運算放大器 322: Operational Amplifier

I1:第一輸入端 I1: The first input terminal

I2:第二輸入端 I2: The second input terminal

O:輸出端 O: output terminal

324:濾波電路 324: Filter circuit

Rf1:第一濾波電阻 Rf1: The first filter resistor

Rf2:第二濾波電阻 Rf2: Second filter resistor

Cf:濾波電容 Cf: filter capacitor

326:第一分壓電路 326: The first voltage divider circuit

R1:第一電阻 R1: first resistor

R2:第二電阻 R2: Second resistor

328:第二分壓電路 328: Second voltage divider circuit

R3:第三電阻 R3: the third resistor

R4:第四電阻 R4: Fourth resistor

34:偏移補償電路 34: Offset compensation circuit

342:第二運算電路 342: Second arithmetic circuit

344:比例積分單元 344: Proportional Integral Unit

2:負載 2: load

Lr:激磁電感 Lr: magnetizing inductance

C:電容 C: Capacitor

CT:電流感測器 CT: current sensor

Vin:輸入電壓 Vin: input voltage

Vo:輸出電壓 Vo: output voltage

Vw:繞組電壓 Vw: winding voltage

Vc:補償電壓 Vc: compensation voltage

Vref:參考電壓 Vref: reference voltage

Ve1:第一誤差值 Ve1: first error value

Ve2:第二誤差值 Ve2: Second error value

Va:平均電壓 Va: average voltage

Vz:零電壓 Vz: zero voltage

PWM:脈寬調變訊號組 PWM: Pulse Width Modulation Signal Group

Sf:回授訊號 Sf: Feedback signal

Sv:電壓控制訊號 Sv: Voltage control signal

S1:第一控制訊號 S1: The first control signal

S2:第二控制訊號 S2: The second control signal

S3:第三控制訊號 S3: The third control signal

S4:第四控制訊號 S4: Fourth control signal

A:箭頭 A: Arrow

(S100)~(S340):步驟 (S100)~(S340): Steps

圖1A為習知的全橋相移轉換器電路架構；圖1B為峰值電流控制的控制方塊圖；圖2為本發明具有磁偏平衡控制之隔離型轉換裝置之電路方塊圖；圖3為本發明控制器與磁偏平衡電路的電路方塊圖；圖4A為本發明隔離型轉換器之第一實施例的電路方塊圖；圖4B為本發明隔離型轉換器之第二實施例的電路方塊圖；圖5A為本發明第一實施例的隔離型轉換裝置修正正磁偏的波形示意圖；圖5B為本發明第一實施例的隔離型轉換裝置修正負磁偏的波形示意圖；圖6A為本發明隔離型轉換裝置之磁偏平衡控制方法的方法流程圖；及圖6B為本發明隔離型轉換裝置之佔空比調整的方法流程圖。 1A is a circuit structure of a conventional full-bridge phase-shift converter; FIG. 1B is a control block diagram of peak current control; FIG. 2 is a circuit block diagram of an isolated converter device with magnetic bias balance control according to the present invention; The circuit block diagram of the controller and the magnetic bias balance circuit of the present invention; FIG. 4A is the circuit block diagram of the first embodiment of the isolated converter of the present invention; FIG. 4B is the circuit block diagram of the second embodiment of the isolated converter of the present invention 5A is a waveform schematic diagram of the isolation-type conversion device of the first embodiment of the present invention correcting positive magnetic bias; FIG. 5B is a waveform schematic diagram of the isolation-type conversion device of the first embodiment of the present invention correcting negative magnetic bias; FIG. 6A is the present invention A method flow chart of a magnetic bias balance control method of an isolated conversion device; and FIG. 6B is a flow chart of a method for adjusting the duty cycle of the isolated conversion device of the present invention.

茲有關本發明之技術內容及詳細說明，配合圖式說明如下：請參閱圖2為本發明具有磁偏平衡控制之隔離型轉換裝置之電路方塊圖。隔離型轉換裝置1的輸入端1A接收輸入電壓Vin，且將輸入電壓Vin轉換為輸出電壓Vo，以通過輸出端1B對負載2供電。隔離型轉換裝置1包括隔離型轉換器10、控制器20與磁偏平衡電路30，且隔離型轉換器10包括變壓器12、至少一開關橋臂14及次級側電路16。變壓器12的初級側包括初級側繞組122，且次級側包括次級側繞組124。開關橋臂14耦接輸入端1A與初級側繞組122，且次級側電路16耦接次級側繞組124與輸出端1B。控制器20耦接開關橋臂14與輸出端1B，且根據輸出端1B的回授訊號Sf提供脈寬調變訊號組PWM控制開關橋臂14。磁偏平衡電路30耦接初級側繞組122的兩端與控制器20，且根據初級側繞組122兩端的繞組電壓Vw而提供對應變壓器12磁偏的補償電壓Vc至控制器20。控制器20根據補償電壓Vc調整脈寬調變訊號組PWM的佔空比，以修正變壓器12的磁偏而達到磁偏平衡的效果。 The technical content and detailed description of the present invention are described below in conjunction with the drawings: Please refer to FIG. 2 , which is a circuit block diagram of the isolated conversion device with magnetic bias balance control of the present invention. The input terminal 1A of the isolated conversion device 1 receives the input voltage Vin, and converts the input voltage Vin into the output voltage Vo, so as to supply power to the load 2 through the output terminal 1B. The isolated converter device 1 includes an isolated converter 10 , a controller 20 and a magnetic bias balance circuit 30 , and the isolated converter 10 includes a transformer 12 , at least one switch arm 14 and a secondary side circuit 16 . The primary side of transformer 12 includes primary side windings 122 and the secondary side includes secondary side windings 124 . The switch arm 14 is coupled to the input terminal 1A and the primary side winding 122 , and the secondary side circuit 16 is coupled to the secondary side winding 124 and the output terminal 1B. The controller 20 is coupled to the switch bridge arm 14 and the output terminal 1B, and provides a pulse width modulation signal group PWM to control the switch bridge arm 14 according to the feedback signal Sf of the output terminal 1B. The magnetic bias balance circuit 30 is coupled to both ends of the primary side winding 122 and the controller 20 , and provides a compensation voltage Vc corresponding to the magnetic bias of the transformer 12 to the controller 20 according to the winding voltage Vw across the primary side winding 122 . The controller 20 adjusts the duty cycle of the pulse width modulation signal group PWM according to the compensation voltage Vc, so as to correct the magnetic bias of the transformer 12 to achieve the effect of magnetic bias balance.

請參閱圖3為本發明控制器與磁偏平衡電路的電路方塊圖，復配合參閱圖2。控制器20包括第一運算電路22、電壓控制器24及脈寬調變電路26。第一運算電路22耦接輸出端1B，且根據輸出端1B的回授訊號Sf與參考電壓Vref之差而提供第一誤差值Ve1至電壓控制器24。電壓控制器24係為一般回授控制的補償器，接收第一誤差值Ve1且根據第一誤差值Ve1而產生電壓控制訊號Sv，且提供電壓控制訊號Sv至脈寬調變電路26。脈寬調變電路26根據電壓控制訊號Sv調製脈寬調變訊號組PWM，且提供脈寬調變訊號組PWM至開關橋臂14，以通過控制開關橋臂14的切換而穩定輸出電壓Vo的電壓值。值得一提，於本發明之一實施例中，控制器20的內部結構僅為最為基本的回授控制架構，並不限定控制器20僅能以此種電路架構實施。 Please refer to FIG. 3 for a circuit block diagram of the controller and the magnetic bias balance circuit of the present invention, and refer to FIG. 2 in combination. The controller 20 includes a first arithmetic circuit 22 , a voltage controller 24 and a pulse width modulation circuit 26 . The first operation circuit 22 is coupled to the output terminal 1B, and provides a first error value Ve1 to the voltage controller 24 according to the difference between the feedback signal Sf of the output terminal 1B and the reference voltage Vref. The voltage controller 24 is a common feedback control compensator, receives the first error value Ve1 and generates a voltage control signal Sv according to the first error value Ve1 , and provides the voltage control signal Sv to the PWM circuit 26 . The pulse width modulation circuit 26 is based on The voltage control signal Sv modulates the pulse width modulation signal group PWM, and provides the pulse width modulation signal group PWM to the switch bridge arm 14 to stabilize the voltage value of the output voltage Vo by controlling the switching of the switch bridge arm 14 . It is worth mentioning that in an embodiment of the present invention, the internal structure of the controller 20 is only the most basic feedback control structure, and it is not limited that the controller 20 can only be implemented with this circuit structure.

磁偏平衡電路30包括取樣電路32與偏移補償電路34，取樣電路32耦接初級側繞組122的兩端，偏移補償電路34耦接取樣電路32且輸出補償電壓Vc至控制器20的脈寬調變電路26。示意的，取樣電路32為差分濾波電路，且差分濾波電路(即取樣電路32)包括運算放大器322、濾波電路324、第一分壓電路326及第二分壓電路328。運算放大器322包括第一輸入端I1、第二輸入端I2及輸出端O，且運算放大器322的輸出端O耦接偏移補償電路34。濾波電路324的一端耦接初級側繞組122的兩端，且另一端分別耦接第一分壓電路326與第二分壓電路328。具體而言，濾波電路324包括第一濾波電阻Rf1、第二濾波電阻Rf2及濾波電容Cf。第一濾波電阻Rf1的一端耦接初級側繞組122的一端，第一濾波電阻Rf1的另一端耦接第一分壓電路326。第二濾波電阻Rf2的一端耦接初級側繞組122的另一端，第二濾波電阻Rf2的另一端耦接第二分壓電路328。濾波電容Cf的一端耦接第一濾波電阻Rf1的另一端，且濾波電容Cf的另一端耦接第二濾波電阻Rf2的另一端。 The magnetic bias balance circuit 30 includes a sampling circuit 32 and an offset compensation circuit 34 . The sampling circuit 32 is coupled to both ends of the primary side winding 122 , and the offset compensation circuit 34 is coupled to the sampling circuit 32 and outputs the compensation voltage Vc to the pulse of the controller 20 . Wide modulation circuit 26 . Illustratively, the sampling circuit 32 is a differential filter circuit, and the differential filter circuit (ie, the sampling circuit 32 ) includes an operational amplifier 322 , a filter circuit 324 , a first voltage dividing circuit 326 and a second voltage dividing circuit 328 . The operational amplifier 322 includes a first input terminal I1 , a second input terminal I2 and an output terminal O, and the output terminal O of the operational amplifier 322 is coupled to the offset compensation circuit 34 . One end of the filter circuit 324 is coupled to both ends of the primary side winding 122 , and the other end is coupled to the first voltage dividing circuit 326 and the second voltage dividing circuit 328 , respectively. Specifically, the filter circuit 324 includes a first filter resistor Rf1 , a second filter resistor Rf2 and a filter capacitor Cf. One end of the first filter resistor Rf1 is coupled to one end of the primary side winding 122 , and the other end of the first filter resistor Rf1 is coupled to the first voltage divider circuit 326 . One end of the second filter resistor Rf2 is coupled to the other end of the primary side winding 122 , and the other end of the second filter resistor Rf2 is coupled to the second voltage divider circuit 328 . One end of the filter capacitor Cf is coupled to the other end of the first filter resistor Rf1, and the other end of the filter capacitor Cf is coupled to the other end of the second filter resistor Rf2.

第一分壓電路326包括串聯的第一電阻R1與第二電阻R2，第一電阻R1耦接濾波電容Cf的一端，且第二電阻R2的兩端分別耦接運算放大器322的第一輸入端I1與輸出端O。第二分壓電路328包括串聯的第三電阻R3與第四電阻R4，第三電阻R3耦接濾波電容Cf的另一端，且第四電阻R4的兩端分別耦接第二輸入端I2與負端點。取樣電路32通過濾波電路324、運算放大器 322、第一分壓電路326及第二分壓電路328將繞組電壓Vw進行濾波取平均和增益調整，產生相關於繞組電壓Vw的電壓平均值的平均電壓Va。值得一提，於本發明之一實施例中，取樣電路32的實施方式僅為示意的實施方式(以類比電路的方式呈現)，並不限制僅能以圖3之差分濾波電路的電路結構實施。舉例另一種可能的實施方式，亦可對繞組電壓Vw的正半週期與負半週期分別取其半週期的電壓平均值，再將正半週期的電壓平均值與負半週期的電壓平均值相減，藉此得到相關於繞組電壓Vw的電壓平均值的一平均電壓Va，以供偏移補償電路34將其差值控制為零，這樣的實施方式有利於使用處理器或微控制器來實現。換言之，只要可得到相關於繞組電壓Vw平均值的電路或方法，皆可應用於本發明之取樣電路32當中。 The first voltage dividing circuit 326 includes a first resistor R1 and a second resistor R2 connected in series, the first resistor R1 is coupled to one end of the filter capacitor Cf, and the two ends of the second resistor R2 are respectively coupled to the first input of the operational amplifier 322 Terminal I1 and output terminal O. The second voltage dividing circuit 328 includes a third resistor R3 and a fourth resistor R4 connected in series, the third resistor R3 is coupled to the other end of the filter capacitor Cf, and the two ends of the fourth resistor R4 are respectively coupled to the second input terminal I2 and the negative endpoint. The sampling circuit 32 passes the filter circuit 324, the operational amplifier 322 . The first voltage dividing circuit 326 and the second voltage dividing circuit 328 perform filtering, averaging and gain adjustment on the winding voltage Vw to generate an average voltage Va that is related to the voltage average value of the winding voltage Vw. It is worth mentioning that in an embodiment of the present invention, the implementation of the sampling circuit 32 is only a schematic implementation (presented in the form of an analog circuit), and it is not limited to be implemented only by the circuit structure of the differential filter circuit shown in FIG. 3 . . For example, in another possible implementation, the voltage average value of the positive half cycle and the negative half cycle of the winding voltage Vw can be obtained respectively, and then the voltage average value of the positive half cycle and the voltage average value of the negative half cycle can be compared. Subtraction, thereby obtaining an average voltage Va relative to the voltage average value of the winding voltage Vw, for the offset compensation circuit 34 to control the difference to zero, such an embodiment is advantageous to use a processor or a microcontroller to achieve . In other words, as long as the circuit or method related to the average value of the winding voltage Vw can be obtained, it can be applied to the sampling circuit 32 of the present invention.

偏移補償電路34為比例積分控制器，且比例積分控制器(即偏移補償電路34)包括第二運算電路342與比例積分單元344。運算電路342用以根據平均電壓Va與零電壓Vz之差而提供第二誤差值Ve2，其中零電壓Vz即代表磁偏平衡時的目標值，其通常為0V的參考電壓。比例積分單元344接收第二誤差值Ve2，根據第二誤差值Ve2產生關聯於磁偏方向與大小的補償電壓Vc，以提供補償電壓Vc至脈寬調變電路26，使脈寬調變電路26得以根據補償電壓Vc調整脈寬調變訊號組PWM的佔空比而修正磁偏。值得一提，於本發明之一實施例中，偏移補償電路34的實施方式僅為較佳的實施方式，並不限制僅能以圖3之比例積分控制器的方式實施。換言之，只要可根據平均電壓Va與零電壓Vz產生補償電壓Vc使平均電壓Va接近於零電壓的任何控制器架構，皆可應用於本發明之偏移補償電路34當中，偏移補償電路34也可使用處理器或微控制器配合數位控制等方式實現。 The offset compensation circuit 34 is a proportional-integral controller, and the proportional-integral controller (ie, the offset compensation circuit 34 ) includes a second operation circuit 342 and a proportional-integral unit 344 . The operation circuit 342 is used to provide a second error value Ve2 according to the difference between the average voltage Va and the zero voltage Vz, where the zero voltage Vz represents the target value when the magnetic bias is balanced, which is usually a reference voltage of 0V. The proportional integration unit 344 receives the second error value Ve2, and generates a compensation voltage Vc related to the direction and magnitude of the magnetic deflection according to the second error value Ve2, so as to provide the compensation voltage Vc to the pulse width modulation circuit 26, so that the pulse width modulation voltage The circuit 26 can adjust the duty ratio of the pulse width modulation signal group PWM according to the compensation voltage Vc to correct the magnetic offset. It is worth mentioning that, in an embodiment of the present invention, the implementation of the offset compensation circuit 34 is only a preferred implementation, and it is not limited to be implemented only in the form of the proportional-integral controller shown in FIG. 3 . In other words, as long as the compensation voltage Vc can be generated according to the average voltage Va and the zero voltage Vz to make the average voltage Va close to zero voltage, any controller structure can be applied to the offset compensation circuit 34 of the present invention. The offset compensation circuit 34 also It can be realized by means of a processor or a microcontroller with digital control.

請參閱圖4A為本發明隔離型轉換器之第一實施例的電路方塊圖，復配合參閱圖2~3。隔離型轉換裝置1中的隔離型轉換器10為全橋轉換器的電路架構，因此開關橋臂14包括第一橋臂142與第二橋臂144。第一橋臂142包括串聯的第一開關Q1與第二開關Q2，第二橋臂144並聯第一橋臂142，且第二橋臂144包括串聯的第三開關Q3與第四開關Q4。初級側繞組122的一端耦接第一開關Q1與第二開關Q2之間的節點，且初級側繞組122的另一端耦接第三開關Q3與第四開關Q4之間的節點。脈寬調變訊號組PWM包括控制第一開關Q1的第一控制訊號S1、控制第二開關Q2的第二控制訊號S2、控制第三開關Q3的第三控制訊號S3及控制第四開關Q4的第四控制訊號S4。控制器20根據輸出端1B的回授訊號Sf而分別提供控制訊號S1~S4控制開關Q1~Q4的切換，以使隔離型轉換器10轉換輸入電壓Vin為輸出電壓Vo。磁偏平衡電路30耦接初級側繞組122的兩端，且根據繞組電壓Vw而提供對應變壓器12磁偏的補償電壓Vc至控制器20，使控制器20調整控制訊號S1~S4的佔空比，進而修正變壓器12的磁偏而達到磁偏平衡的效果。 Please refer to FIG. 4A , which is a circuit block diagram of the isolated converter according to the first embodiment of the present invention, and refer to FIGS. 2 to 3 in combination. The isolated converter 10 in the isolated converter 1 has a circuit structure of a full-bridge converter, so the switching bridge arm 14 includes a first bridge arm 142 and a second bridge arm 144 . The first bridge arm 142 includes a first switch Q1 and a second switch Q2 connected in series, the second bridge arm 144 is connected in parallel with the first bridge arm 142 , and the second bridge arm 144 includes a third switch Q3 and a fourth switch Q4 connected in series. One end of the primary side winding 122 is coupled to the node between the first switch Q1 and the second switch Q2, and the other end of the primary side winding 122 is coupled to the node between the third switch Q3 and the fourth switch Q4. The pulse width modulation signal group PWM includes a first control signal S1 for controlling the first switch Q1, a second control signal S2 for controlling the second switch Q2, a third control signal S3 for controlling the third switch Q3, and a third control signal S3 for controlling the fourth switch Q4. The fourth control signal S4. The controller 20 provides control signals S1 to S4 respectively according to the feedback signal Sf of the output terminal 1B to control the switching of the switches Q1 to Q4 , so that the isolated converter 10 converts the input voltage Vin to the output voltage Vo. The magnetic bias balance circuit 30 is coupled to both ends of the primary side winding 122, and provides a compensation voltage Vc corresponding to the magnetic bias of the transformer 12 to the controller 20 according to the winding voltage Vw, so that the controller 20 can adjust the duty ratio of the control signals S1-S4 , and then correct the magnetic bias of the transformer 12 to achieve the effect of magnetic bias balance.

進一步而言，請參閱圖5A為本發明第一實施例的隔離型轉換裝置修正正磁偏的波形示意圖、請參閱圖5B為本發明第一實施例的隔離型轉換裝置修正負磁偏的波形示意圖，復配合參閱圖2~4A。磁偏平衡電路30所提供的補償電壓Vc會對應變壓器的磁偏方向，磁偏具向正半週偏離的方向或向負半週偏離的方向。請參閱圖5A，當變壓器12所發生的磁偏的磁偏方向為正，繞組電壓Vw正半週的有效責任週期會比負半週來的大。此時，磁偏平衡電路30根據繞組電壓Vw所提供的補償電壓Vc會為正值(即大於0V)，控制器20根據正值的補償電壓Vc調小第一控制訊號S1與第四控制訊號S4的佔空比(以箭頭A方向表示縮減佔空比)，以降低正半週的有效責任週期，進而修正欲往正值偏離的磁通。此處的有效責任週期是指繞組電壓Vw實際上存在電壓的責任週期，以圖4A的全橋轉換器為例，一般可以使控制訊號S1、S4同步啟閉，則有效責任週期等於控制訊號S1或控制訊號S4的責任週期。若使用相移控制，因控制訊號S1、S4不會同步，則只有在控制訊號S1、S4同時高準位時，繞組上才會有電壓，所以此時有效責任週期是控制訊號S1、S4高準位重疊的時間。 Further, please refer to FIG. 5A , which is a schematic diagram of the waveform of the isolated conversion device correcting the positive magnetic bias according to the first embodiment of the present invention, and please refer to FIG. 5B , which is the waveform of the isolated conversion device correcting the negative magnetic bias according to the first embodiment of the present invention. Schematic diagram, please refer to Figures 2-4A for a combination. The compensation voltage Vc provided by the magnetic bias balancing circuit 30 corresponds to the magnetic bias direction of the transformer, and the magnetic bias deviates to the positive half cycle direction or the negative half cycle direction. Referring to FIG. 5A , when the magnetic bias direction of the magnetic bias generated by the transformer 12 is positive, the effective duty cycle of the positive half cycle of the winding voltage Vw will be larger than that of the negative half cycle. At this time, the compensation voltage Vc provided by the magnetic bias balance circuit 30 according to the winding voltage Vw will be positive (ie greater than 0V), and the controller 20 will reduce the first control signal S1 and the fourth control signal according to the positive compensation voltage Vc The duty cycle of S4 (in the direction of arrow A means reducing the duty cycle) to reduce the effective duty cycle of the positive half cycle, and then correct the magnetic flux that is going to deviate from the positive value. The effective duty cycle here refers to the duty cycle in which the winding voltage Vw actually has a voltage. Taking the full-bridge converter in FIG. 4A as an example, the control signals S1 and S4 can generally be turned on and off synchronously, and the effective duty cycle is equal to the control signal S1. Or the duty cycle of the control signal S4. If the phase shift control is used, since the control signals S1 and S4 will not be synchronized, there will be voltage on the winding only when the control signals S1 and S4 are high at the same time, so the effective duty cycle at this time is when the control signals S1 and S4 are high. Level overlap time.

反之，請參閱圖5B，當變壓器12所發生的磁偏的磁偏方向為負，繞組電壓Vw負半週的有效責任週期會比正半週來的大。此時，磁偏平衡電路30根據繞組電壓Vw所提供的補償電壓Vc會為負值(即小於0V)，控制器20根據負值的補償電壓Vc調小第二控制訊號S2與第三控制訊號S3的佔空比(以箭頭A方向表示縮減佔空比)，以降低負半週的有效責任週期，進而修正負磁偏。值得一提，於本發明之一實施例中，繞組電壓Vw與補償電壓Vc正負值的對應僅為舉例，其也可以相反地為正半週有效責任週期較大的繞組電壓Vw對應產生負值的補償電壓Vc，只要能控制使有效責任週期較大的半週能減少有效責任週期即可。 On the contrary, referring to FIG. 5B , when the magnetic bias of the transformer 12 is negative, the effective duty cycle of the negative half cycle of the winding voltage Vw will be larger than that of the positive half cycle. At this time, the compensation voltage Vc provided by the magnetic bias balance circuit 30 according to the winding voltage Vw will be negative (ie, less than 0V), and the controller 20 will reduce the second control signal S2 and the third control signal according to the negative compensation voltage Vc The duty cycle of S3 (reduced in the direction of arrow A) can reduce the effective duty cycle of the negative half cycle, thereby correcting the negative magnetic bias. It is worth mentioning that, in an embodiment of the present invention, the correspondence between the positive and negative values of the winding voltage Vw and the compensation voltage Vc is only an example, and it can also be reversed to generate a negative value corresponding to the winding voltage Vw with a larger effective duty cycle in the positive half cycle. The compensation voltage Vc can be controlled so that the effective duty cycle can be reduced by a half cycle with a larger effective duty cycle.

請參閱圖4B為本發明隔離型轉換器之第二實施例的電路方塊圖，復配合參閱圖2~4A、5A~5B。本實施例之隔離型轉換裝置1’與圖4A之隔離型轉換裝置1差異在於，隔離型轉換器10’為半橋轉換器的電路架構。開關橋臂14包括第一橋臂142與電容組146，第一橋臂142包括串聯的第一開關Q1與第二開關Q2，電容組146並聯第一橋臂142，且電容組146包括串聯的第一電容C1與第二電容C2。初級側繞組122的一端耦接第一開關Q1與第二開關Q2之間的節點，且初級側繞組122的另一端耦接第一電容C1與第二電容C2之間的節點。脈寬調變訊號組PWM包括控制第一開關Q1的第一控制訊號S1與控制第二開關Q2的第二控制訊號S2，且控制器20根據輸出端1B的回授訊號Sf而分別提供控制訊號S1~S2控制開關Q1~Q2的切換，以使隔離型轉換器10轉換輸入電壓Vin為輸出電壓Vo。磁偏平衡電路30根據繞組電壓Vw而提供對應變壓器12磁偏的補償電壓Vc至控制器20，使控制器20調整控制訊號S1~S2的佔空比，進而修正變壓器12的磁偏而達到磁偏平衡的效果。值得一提，於本發明之一實施例中，隔離型轉換裝置1’修正磁通偏離的波形相似於圖5A與圖5B，繞組電壓Vw正半週的責任週期較大時，調小第一控制訊號S1的佔空比，且繞組電壓Vw負半週的責任週期較大時，調小第二控制訊號S2的佔空比。 Please refer to FIG. 4B , which is a circuit block diagram of the isolated converter according to the second embodiment of the present invention, and refer to FIGS. 2 to 4A and 5A to 5B in combination. The difference between the isolated converter device 1' of the present embodiment and the isolated converter device 1 of FIG. 4A is that the isolated converter 10' has a circuit structure of a half-bridge converter. The switch bridge arm 14 includes a first bridge arm 142 and a capacitor bank 146, the first bridge arm 142 includes a first switch Q1 and a second switch Q2 connected in series, the capacitor bank 146 is connected in parallel with the first bridge arm 142, and the capacitor bank 146 includes a series connection The first capacitor C1 and the second capacitor C2. One end of the primary side winding 122 is coupled to the node between the first switch Q1 and the second switch Q2, and the other end of the primary side winding 122 is coupled to the node between the first capacitor C1 and the second capacitor C2. node. The pulse width modulation signal group PWM includes a first control signal S1 for controlling the first switch Q1 and a second control signal S2 for controlling the second switch Q2, and the controller 20 respectively provides the control signals according to the feedback signal Sf of the output terminal 1B S1 ˜ S2 control the switching of switches Q1 ˜ Q2 , so that the isolated converter 10 converts the input voltage Vin to the output voltage Vo. The magnetic bias balance circuit 30 provides the compensation voltage Vc corresponding to the magnetic bias of the transformer 12 to the controller 20 according to the winding voltage Vw, so that the controller 20 adjusts the duty cycle of the control signals S1-S2, and then corrects the magnetic bias of the transformer 12 to achieve the magnetic bias. Balanced effect. It is worth mentioning that, in an embodiment of the present invention, the waveform of the isolated conversion device 1 ′ correcting the magnetic flux deviation is similar to that shown in FIGS. 5A and 5B . When the duty cycle of the positive half cycle of the winding voltage Vw is larger, the first When the duty cycle of the control signal S1 and the duty cycle of the negative half cycle of the winding voltage Vw are relatively large, the duty cycle of the second control signal S2 is reduced.

值得一提，於本發明之一實施例中，次級側電路16可以為圖4A與4B所示的全橋整流電路架構，但也可以為中心抽頭式的整流電路，其可以依照電路的實際需求而實施。而且，雖然磁偏平衡電路30也可使用次級側繞組124進行磁偏平衡的控制，但是由於次級側電路16的電路類型不同，次級側繞組124的結構也會改變(單一繞組或中心抽頭式)，因此會造成磁偏平衡電路30無法通用於次級側電路16所有的電路架構。尤其是中心抽頭式的繞組中，兩繞組的參數無法做成完全相同，會產生即便使用磁偏平衡的控制，仍然無法達到完全磁偏平衡的效果。而本發明磁偏平衡電路30使用初級側繞組122進行磁偏平衡的控制的好處在於，無論初級側的開關橋臂14為單橋臂或雙橋臂(如圖4A與4B所示)，磁偏平衡電路30皆通用，可達成增加使用便利性之功效。而且，初級側繞組122僅有單組繞組，使用本發明的磁偏平衡控制，即可以達到完全磁偏平衡的效果。 It is worth mentioning that, in an embodiment of the present invention, the secondary side circuit 16 may be the full-bridge rectifier circuit structure shown in FIGS. 4A and 4B , but may also be a center-tapped rectifier circuit, which may be based on the actual circuit conditions. needs to be implemented. Moreover, although the magnetic bias balance circuit 30 can also use the secondary side winding 124 to control the magnetic bias balance, due to the different circuit types of the secondary side circuit 16, the structure of the secondary side winding 124 will also change (single winding or central tapped), so the magnetic bias balance circuit 30 cannot be used in all circuit structures of the secondary side circuit 16 . Especially in the center-tapped winding, the parameters of the two windings cannot be made exactly the same, and even if the control of magnetic bias balance is used, the effect of complete magnetic bias balance cannot be achieved. The advantage of using the primary side winding 122 for the magnetic bias balance control of the magnetic bias balance circuit 30 of the present invention is that no matter whether the switching bridge arm 14 on the primary side is a single bridge arm or a double bridge arm (as shown in FIGS. 4A and 4B ), the magnetic The bias balance circuit 30 is universal, and can achieve the effect of increasing the convenience of use. Moreover, the primary side winding 122 has only a single set of windings, and the magnetic bias balance control of the present invention can achieve the effect of complete magnetic bias balance.

綜上所述，由於本發明之隔離型轉換裝置1利用取樣變壓器12初級側繞組122兩端的繞組電壓Vw，且經由濾波線路(即取樣電路32)取其平均值，再透過控制器(即偏移補償電路34)將其控制為0而修正磁偏。初級側繞組122兩端的繞組電壓Vw的平均值等同電壓與時間(有效責任週期)的乘積，如此可以簡單的完成變壓器磁偏的補償，無需使用增加電流感測器的控制方式，也無需增加隔離電容，進而達到降低電路體積及電路成本之功效。 To sum up, because the isolated conversion device 1 of the present invention uses the winding voltage Vw across the primary side winding 122 of the transformer 12 to sample, and obtains the average value through the filter circuit (ie the sampling circuit 32 ), and then passes the controller (ie the biasing circuit 32 ) The offset compensation circuit 34) controls it to 0 to correct the magnetic offset. The average value of the winding voltage Vw at both ends of the primary side winding 122 is equivalent to the product of voltage and time (effective duty cycle). In this way, the compensation of the magnetic bias of the transformer can be simply completed, without the need to use the control method of adding a current sensor or increase the isolation. Capacitance, thereby achieving the effect of reducing circuit volume and circuit cost.

請參閱圖6A為本發明隔離型轉換裝置之磁偏平衡控制方法的方法流程圖，復配合參閱圖2~5B。磁偏平衡控制方法適用於控制具有變壓器12的隔離型轉換器1，且變壓器12的初級側包括至少一開關橋臂14。磁偏平衡控制方法包括：提供脈寬調變訊號組控制開關橋臂切換而使隔離型轉換器將輸入電壓轉換為輸出電壓(S100)。控制器20根據隔離型轉換裝置1的輸出端1B的回授訊號Sf提供脈寬調變訊號組PWM控制開關橋臂14的切換，使隔離型轉換器1將輸入電壓Vin轉換為輸出電壓Vo。然後，根據變壓器的初級側繞組兩端的繞組電壓與零電壓而提供對應變壓器的磁偏的補償電壓(S200)。磁偏平衡電路30中的取樣電路32通過濾波電路324將繞組電壓Vw進行濾波取平均後，通過運算放大器322、第一分壓電路326及第二分壓電路328調整增益，產生相關於繞組電壓Vw的電壓平均值的平均電壓Va。運算電路342根據平均電壓Va與零電壓Vz之差而提供第二誤差值Ve2，比例積分單元344根據第二誤差值Ve2產生關聯於磁偏方向與大小的補償電壓Vc，以提供補償電壓Vc至脈寬調變電路26。最後，根據補償電壓調整脈寬調變訊號組的佔空比，以修正磁偏(S300)。脈寬調變電路26根據補償電壓Vc調整脈寬調變訊號組PWM的佔空比而修正磁偏。 Please refer to FIG. 6A for a method flow chart of the magnetic bias balance control method of the isolated conversion device according to the present invention, and refer to FIGS. 2 to 5B in combination. The magnetic bias balance control method is suitable for controlling the isolated converter 1 having the transformer 12 , and the primary side of the transformer 12 includes at least one switching bridge arm 14 . The magnetic bias balance control method includes: providing a pulse width modulation signal group to control the switching of the switch bridge arm so that the isolated converter converts the input voltage into the output voltage ( S100 ). The controller 20 provides the pulse width modulation signal group PWM to control the switching of the switch arm 14 according to the feedback signal Sf of the output end 1B of the isolated converter 1 , so that the isolated converter 1 converts the input voltage Vin into the output voltage Vo. Then, according to the winding voltage across the primary side winding of the transformer and the zero voltage, a compensation voltage corresponding to the magnetic bias of the transformer is provided ( S200 ). The sampling circuit 32 in the magnetic bias balance circuit 30 filters and averages the winding voltage Vw through the filter circuit 324, and then adjusts the gain through the operational amplifier 322, the first voltage divider circuit 326 and the second voltage divider circuit 328 to generate a voltage related to the voltage Vw. The average voltage Va of the voltage average value of the winding voltage Vw. The arithmetic circuit 342 provides a second error value Ve2 according to the difference between the average voltage Va and the zero voltage Vz, and the proportional-integration unit 344 generates a compensation voltage Vc related to the direction and magnitude of the magnetic deflection according to the second error value Ve2 to provide the compensation voltage Vc to Pulse width modulation circuit 26 . Finally, the duty ratio of the PWM signal group is adjusted according to the compensation voltage to correct the magnetic offset (S300). The pulse width modulation circuit 26 adjusts the duty cycle of the pulse width modulation signal group PWM according to the compensation voltage Vc to correct the magnetic bias.

請參閱圖6B為本發明隔離型轉換裝置之佔空比調整的方法流程圖，復配合參閱圖2~6A。步驟(S300)包括，提供對應磁偏方向的補償電壓(S320)。磁偏平衡電路30所提供的補償電壓Vc會對應磁偏的磁偏方向，且磁偏具向正半週偏離的方向或向負半週偏離的方向。然後，根據對應磁偏方向的補償電壓調降對應偏離方向的控制訊號的佔空比(S340)。當隔離型轉換裝置1中的隔離型轉換器10為全橋轉換器的電路架構時，且變壓器12所發生的磁偏的磁偏方向為正，繞組電壓Vw正半週的有效責任週期會比負半週來的大。此時，磁偏平衡電路30根據繞組電壓Vw所提供的補償電壓Vc會為正值，控制器20根據正值的補償電壓Vc調小第一控制訊號S1與第四控制訊號S4的佔空比。反之，則調小第二控制訊號S2與第三控制訊號S3的佔空比。 Please refer to FIG. 6B for a flowchart of a method for adjusting the duty cycle of the isolated conversion device according to the present invention, and refer to FIGS. 2 to 6A in combination. The step (S300) includes providing a compensation voltage corresponding to the magnetic deflection direction (S320). The compensation voltage Vc provided by the magnetic bias balance circuit 30 corresponds to the magnetic bias direction of the magnetic bias, and the magnetic bias deviates to the direction of the positive half cycle or the direction of the negative half cycle. Then, the duty ratio of the control signal corresponding to the deviating direction is decreased according to the compensation voltage corresponding to the magnetic deviating direction (S340). When the isolated converter 10 in the isolated converter 1 is a full-bridge converter, and the magnetic bias of the transformer 12 is positive, the effective duty cycle of the positive half cycle of the winding voltage Vw will be shorter than Negative half week to the big. At this time, the compensation voltage Vc provided by the magnetic bias balance circuit 30 according to the winding voltage Vw will be a positive value, and the controller 20 will reduce the duty ratio of the first control signal S1 and the fourth control signal S4 according to the positive compensation voltage Vc . On the contrary, the duty ratio of the second control signal S2 and the third control signal S3 is reduced.

當隔離型轉換裝置1中的隔離型轉換器10為半橋轉換器的電路架構時，且變壓器12所發生的磁偏的磁偏方向為正，繞組電壓Vw正半週的責任週期會比負半週來的大。此時，磁偏平衡電路30根據繞組電壓Vw所提供的補償電壓Vc會為正值，控制器20根據正值的補償電壓Vc調小第一控制訊號S1的佔空比。反之，則調小第二控制訊號S2的佔空比。 When the isolated converter 10 in the isolated converter 1 is a circuit structure of a half-bridge converter, and the magnetic bias of the transformer 12 is positive, the duty cycle of the positive half cycle of the winding voltage Vw will be longer than the negative one. Big for half a week. At this time, the compensation voltage Vc provided by the magnetic bias balance circuit 30 according to the winding voltage Vw is positive, and the controller 20 reduces the duty cycle of the first control signal S1 according to the positive compensation voltage Vc. Otherwise, the duty ratio of the second control signal S2 is reduced.

惟，以上所述，僅為本發明較佳具體實施例之詳細說明與圖式，惟本發明之特徵並不侷限於此，並非用以限制本發明，本發明之所有範圍應以下述之申請專利範圍為準，凡合於本發明申請專利範圍之精神與其類似變化之實施例，皆應包括於本發明之範疇中，任何熟悉該項技藝者在本發明之領域內，可輕易思及之變化或修飾皆可涵蓋在以下本案之專利範圍。 However, the above descriptions are only the detailed descriptions and drawings of the preferred embodiments of the present invention, but the features of the present invention are not limited thereto, and are not intended to limit the present invention. The scope of the patent shall prevail, and all embodiments that are consistent with the spirit of the scope of the patent application of the present invention and similar variations thereof shall be included in the scope of the present invention. Anyone who is familiar with the art in the field of the present invention can easily think Changes or modifications can be covered by the following patent scope of the present case.

1:隔離型轉換裝置 1: Isolated conversion device

1A:輸入端 1A: input terminal

1B:輸出端 1B: output terminal

10:隔離型轉換器 10: Isolated converter

12:變壓器 12: Transformer

122:初級側繞組 122: Primary side winding

124:次級側繞組 124: Secondary side winding

14:開關橋臂 14: switch bridge arm

16:次級側電路 16: Secondary side circuit

20:控制器 20: Controller

30:磁偏平衡電路 30: Magnetic bias balance circuit

2:負載 2: load

Vin:輸入電壓 Vin: input voltage

Vo:輸出電壓 Vo: output voltage

Vw:繞組電壓 Vw: winding voltage

Vc:補償電壓 Vc: compensation voltage

PWM:脈寬調變訊號組 PWM: Pulse Width Modulation Signal Group

Sf:回授訊號 Sf: Feedback signal

Claims

一種具有磁偏平衡控制之隔離型轉換裝置，包括：一隔離型轉換器，包括一變壓器，該變壓器的一初級側包括一初級側繞組與至少一開關橋臂；一控制器，耦接該至少一開關橋臂，且提供一脈寬調變訊號組控制該至少一開關橋臂；及一磁偏平衡電路，耦接該初級側繞組的兩端與該控制器，且根據該初級側繞組兩端的一繞組電壓的一電壓平均值而提供一補償電壓至該控制器；其中該控制器根據該補償電壓調整該脈寬調變訊號組的佔空比。 An isolated conversion device with magnetic bias balance control, comprising: an isolated converter, including a transformer, a primary side of the transformer includes a primary side winding and at least one switch bridge arm; a controller, coupled to the at least one a switch bridge arm, and a pulse width modulation signal group is provided to control the at least one switch bridge arm; and a magnetic bias balance circuit is coupled to both ends of the primary side winding and the controller, and according to the two ends of the primary side winding A voltage average value of a winding voltage at the terminal is used to provide a compensation voltage to the controller; wherein the controller adjusts the duty cycle of the PWM signal group according to the compensation voltage.

如請求項1所述之隔離型轉換裝置，其中該磁偏平衡電路包括：一取樣電路，耦接該初級側繞組的兩端，且產生關於該電壓平均值的一平均電壓；及一偏移補償電路，耦接該取樣電路，且根據該平均電壓與一零電壓提供該補償電壓。 The isolated conversion device of claim 1, wherein the magnetic bias balance circuit comprises: a sampling circuit coupled to both ends of the primary side winding and generating an average voltage with respect to the average value of the voltage; and an offset The compensation circuit is coupled to the sampling circuit and provides the compensation voltage according to the average voltage and a zero voltage.

如請求項2所述之隔離型轉換裝置，其中該取樣電路為一差分濾波電路，且該差分濾波電路包括：一運算放大器，包括一第一輸入端、一第二輸入端及一輸出端，且該輸出端耦接該偏移補償電路；一濾波電路，耦接該初級側繞組的兩端；一第一分壓電路，包括串聯的一第一電阻與一第二電阻，該第一電阻耦接該濾波電路，且該第二電阻的兩端分別耦接該第一輸入端與該輸出端；及一第二分壓電路，包括串聯的一第三電阻與一第四電阻，該第三電阻耦接該濾波電路，且該第四電阻的兩端分別耦接該第二輸入端與一負極端。 The isolated conversion device as claimed in claim 2, wherein the sampling circuit is a differential filter circuit, and the differential filter circuit comprises: an operational amplifier including a first input terminal, a second input terminal and an output terminal, and the output end is coupled to the offset compensation circuit; a filter circuit is coupled to both ends of the primary side winding; a first voltage divider circuit includes a first resistor and a second resistor connected in series, the first A resistor is coupled to the filter circuit, and two ends of the second resistor are respectively coupled to the first input end and the output end; and A second voltage divider circuit includes a third resistor and a fourth resistor connected in series, the third resistor is coupled to the filter circuit, and two ends of the fourth resistor are respectively coupled to the second input terminal and a negative extreme.

如請求項3所述之隔離型轉換裝置，其中該濾波電路包括：一第一濾波電阻，一端耦接該初級側繞組的一端，另一端耦接該第一電阻；一第二濾波電阻，一端耦接該初級側繞組的另一端，另一端耦接該第三電阻；及一濾波電容，一端耦接該第一濾波電阻的另一端，且另一端耦接該第二濾波電阻的另一端。 The isolated conversion device according to claim 3, wherein the filter circuit comprises: a first filter resistor, one end of which is coupled to one end of the primary side winding, and the other end of which is coupled to the first resistor; a second filter resistor, one end of which is coupled The other end is coupled to the primary side winding, and the other end is coupled to the third resistor; and a filter capacitor, one end is coupled to the other end of the first filter resistor, and the other end is coupled to the other end of the second filter resistor.

如請求項2所述之隔離型轉換裝置，其中該偏移補償電路為一比例積分控制器，且該比例積分控制器包括：一運算電路，耦接該取樣電路，且根據該平均電壓與該零電壓之差而提供一誤差值；一比例積分單元，接收該誤差值，且根據該誤差值產生該補償電壓。 The isolated conversion device as claimed in claim 2, wherein the offset compensation circuit is a proportional-integral controller, and the proportional-integral controller comprises: an arithmetic circuit, coupled to the sampling circuit, and based on the average voltage and the The difference between zero voltages provides an error value; a proportional-integration unit receives the error value and generates the compensation voltage according to the error value.

如請求項1所述之隔離型轉換裝置，其中該至少一開關橋臂包括：一第一橋臂，包括串聯的一第一開關與一第二開關；及一電容組，並聯該第一橋臂，且包括串聯的一第一電容與一第二電容；其中，該初級側繞組的一端耦接該第一開關與該第二開關之間的節點，且該初級側繞組的另一端耦接該第一電容與該第二電容之間的節點；該脈寬調變訊號組包括控制該第一開關的一第一控制訊號與控制該第二開關的一第二控制訊號。 The isolated conversion device as claimed in claim 1, wherein the at least one switch bridge arm comprises: a first bridge arm including a first switch and a second switch connected in series; and a capacitor bank connected in parallel with the first bridge arm, and includes a first capacitor and a second capacitor connected in series; wherein, one end of the primary side winding is coupled to the node between the first switch and the second switch, and the other end of the primary side winding is coupled to A node between the first capacitor and the second capacitor; the PWM signal group includes a first control signal for controlling the first switch and a second control signal for controlling the second switch.

如請求項6所述之隔離型轉換裝置，其中該磁偏平衡電路所提供的該補償電壓關聯於該變壓器的一第一磁偏方向，該控制器根據關聯於該第一磁偏方向的該補償電壓調降該第一控制訊號的佔空比。 The isolated conversion device as claimed in claim 6, wherein the compensation voltage provided by the magnetic bias balance circuit is related to a first magnetic bias direction of the transformer, and the controller is based on the The compensation voltage reduces the duty cycle of the first control signal.

如請求項6所述之隔離型轉換裝置，其中該磁偏平衡電路所提供的該補償電壓關聯於該變壓器的一第二磁偏方向，該控制器根據關聯於該第二磁偏方向的該補償電壓調降該第二控制訊號的佔空比。 The isolated conversion device as claimed in claim 6, wherein the compensation voltage provided by the magnetic bias balancing circuit is related to a second magnetic bias direction of the transformer, and the controller is related to the second magnetic bias direction according to the The compensation voltage reduces the duty cycle of the second control signal.

如請求項1所述之隔離型轉換裝置，其中該至少一開關橋臂包括：一第一橋臂，包括串聯的一第一開關與一第二開關；及一第二橋臂，並聯該第一橋臂，且包括串聯的一第三開關與一第四開關；其中，該初級側繞組的一端耦接該第一開關與該第二開關之間的節點，且該初級側繞組的另一端耦接該第三開關與該第四開關之間的節點；該脈寬調變訊號組包括控制該第一開關的一第一控制訊號、控制該第二開關的一第二控制訊號、控制該第三開關的一第三控制訊號及控制該第四開關的一第四控制訊號。 The isolated conversion device of claim 1, wherein the at least one switch bridge arm comprises: a first bridge arm including a first switch and a second switch connected in series; and a second bridge arm connected in parallel with the first switch a bridge arm including a third switch and a fourth switch connected in series; wherein one end of the primary side winding is coupled to the node between the first switch and the second switch, and the other end of the primary side winding is coupled to a node between the third switch and the fourth switch; the PWM signal group includes a first control signal for controlling the first switch, a second control signal for controlling the second switch, and a control signal for controlling the A third control signal for the third switch and a fourth control signal for controlling the fourth switch.

如請求項9所述之隔離型轉換裝置，其中該磁偏平衡電路所提供的該補償電壓對應該變壓器的一第一磁偏方向，該控制器根據對應於該第一磁偏方向的該補償電壓調降該第一控制訊號與該第四控制訊號的佔空比。 The isolated conversion device as claimed in claim 9, wherein the compensation voltage provided by the magnetic bias balance circuit corresponds to a first magnetic bias direction of the transformer, and the controller is based on the compensation corresponding to the first magnetic bias direction The voltage reduces the duty ratio of the first control signal and the fourth control signal.

如請求項9所述之隔離型轉換裝置，其中該磁偏平衡電路所提供的該補償電壓對應該變壓器的一第二磁偏方向，該控制器根據對應於該第二磁偏方向的該補償電壓調降該第二控制訊號與該第三控制訊號的佔空比。 The isolated conversion device as claimed in claim 9, wherein the compensation voltage provided by the magnetic bias balance circuit corresponds to a second magnetic bias direction of the transformer, and the controller is based on the compensation corresponding to the second magnetic bias direction The voltage reduces the duty ratio of the second control signal and the third control signal.

一種隔離型轉換裝置之磁偏平衡控制方法，該隔離型轉換裝置包括一隔離型轉換器，且該隔離型轉換器包括一變壓器與耦接該變壓器初級側的至少一開關橋臂，該磁偏平衡控制方法包括下列步驟：(a)提供一脈寬調變訊號組控制該至少一開關橋臂切換而使該隔離型轉換器將一輸入電壓轉換為一輸出電壓；(b)根據該變壓器的一初級側繞組兩端的一繞組電壓而提供對應該變壓器的一磁偏的一補償電壓；及(c)根據該補償電壓調整該脈寬調變訊號組的佔空比，以修正該磁偏。 A magnetic bias balance control method for an isolated conversion device, the isolated conversion device includes an isolated converter, and the isolated converter includes a transformer and at least one switch bridge arm coupled to the primary side of the transformer, the magnetic bias The balance control method includes the following steps: (a) providing a pulse width modulation signal group to control the switching of the at least one switch bridge arm so that the isolated converter converts an input voltage into an output voltage; (b) according to the transformer A winding voltage across a primary side winding provides a compensation voltage corresponding to a magnetic bias of the transformer; and (c) adjusting the duty cycle of the PWM signal group according to the compensation voltage to correct the magnetic bias.

如請求項12所述之磁偏平衡控制方法，其中步驟(b)包括：(b1)產生關於該繞組電壓的一電壓平均值的一平均電壓；(b2)根據該平均電壓與一零電壓之差而提供一誤差值；及(b3)根據該誤差值產生該補償電壓。 The magnetic bias balance control method as claimed in claim 12, wherein step (b) comprises: (b1) generating an average voltage with respect to an average voltage value of the winding voltage; (b2) according to the difference between the average voltage and a zero voltage and (b3) generating the compensation voltage according to the error value.

如請求項12所述之磁偏平衡控制方法，其中該脈寬調變訊號組包括控制該至少一開關橋臂的一第一控制訊號與一第二控制訊號，且步驟(c)包括：(c11)提供關聯於該磁偏中的一第一磁偏方向的該補償電壓；及(c12)根據關聯於該第一磁偏方向的該補償電壓調降該第一控制訊號的佔空比。 The magnetic bias balance control method of claim 12, wherein the PWM signal set includes a first control signal and a second control signal for controlling the at least one switch arm, and step (c) includes: ( c11) providing the compensation voltage associated with a first magnetic bias direction in the magnetic bias; and (c12) reducing the duty cycle of the first control signal according to the compensation voltage associated with the first magnetic bias direction.

如請求項12所述之磁偏平衡控制方法，其中該脈寬調變訊號組包括控制該至少一開關橋臂的一第一控制訊號與一第二控制訊號，且步驟(c)包括：(c21)提供對應該磁偏中的一第二磁偏方向的該補償電壓；及 (c22)根據對應該第二磁偏方向的該補償電壓調降該第二控制訊號的佔空比。 The magnetic bias balance control method of claim 12, wherein the PWM signal set includes a first control signal and a second control signal for controlling the at least one switch arm, and step (c) includes: ( c21) providing the compensation voltage corresponding to a second magnetic bias direction in the magnetic bias; and (c22) Decrease the duty ratio of the second control signal according to the compensation voltage corresponding to the second magnetic deflection direction.

如請求項12所述之磁偏平衡控制方法，其中該脈寬調變訊號組包括控制該至少一開關橋臂的一第一控制訊號、一第二控制訊號、一第三控制訊號及一第四控制訊號，且步驟(c)包括：(c31)提供對應該磁偏中的一第一磁偏方向的該補償電壓；及(c32)根據對應該第一磁偏方向的該補償電壓調降該第一控制訊號與該第四控制訊號的佔空比。 The magnetic bias balance control method of claim 12, wherein the PWM signal set includes a first control signal, a second control signal, a third control signal and a first control signal for controlling the at least one switch arm Four control signals, and step (c) includes: (c31) providing the compensation voltage corresponding to a first magnetic bias direction in the magnetic bias; and (c32) reducing the compensation voltage according to the compensation voltage corresponding to the first magnetic bias direction duty ratio of the first control signal and the fourth control signal.

如請求項12所述之磁偏平衡控制方法，其中該脈寬調變訊號組包括控制該至少一開關橋臂的一第一控制訊號、一第二控制訊號、一第三控制訊號及一第四控制訊號，且步驟(c)包括：(c41)提供對應該磁偏中的一第二磁偏方向的該補償電壓；及(c42)根據對應該第二磁偏方向的該補償電壓調降該第二控制訊號與該的三控制訊號的佔空比。 The magnetic bias balance control method of claim 12, wherein the PWM signal set includes a first control signal, a second control signal, a third control signal and a first control signal for controlling the at least one switch arm Four control signals, and step (c) includes: (c41) providing the compensation voltage corresponding to a second magnetic bias direction in the magnetic bias; and (c42) reducing the compensation voltage according to the compensation voltage corresponding to the second magnetic bias direction The duty ratio of the second control signal and the three control signals.