201230652 六、發明說明： 【發明所屬之技術領域】 本發明係關於-種電源控制電路，特別關於—種具 寬調變之電源控制電路。 、义 【先前技術】 脈見㈣（Pulse WidthM〇dulati〇n，pwM)為切換 中的—種傳統技術，其方法為控制切換元 件的V通知間以達到所需之負載需求。 〇月，’、，、圖1所不，其為習知一種電源控制電路1的功 能方塊圖。電源控制電路！具有一電源單元u、一轉換扣 兀12電壓回授單元13、一控制單元14以及—前 凡15。電源単元11係輸出一電源訊號Ps。轉換單元 係依據電源訊號PS輸出一驅動訊號DS，以驅動 置L。電麼回授單元13係依據驅動訊號DS的變化（即^ 載二L，變化).輸出回授訊號 。早7015係依據輸人轉換單元12之電源訊號Ps 訊號1s。而控制單元14係依據回授訊 A C 戒IS輸出一控制訊號^，以控制轉換 12之-切換開關（圖未顯示）導通或截止。其中，控 號C S可控制切換開關之責任週期（即控制導通時間 由切換開關之不同責任週期的導通，可使轉換單元玉曰 生之驅動訊號DS與負載裝置L達到平衡。 座 例如，當負载裝置L的負載降低時，驅動訊號仍的 201230652 電壓值將上升，電壓回授單元13感測驅動訊號⑽ 並輸出回授訊號Vc。另外，負載裝置L的負載降低^ 驅動訊號DS的電流值亦降低，使得輸入轉換單元u 源訊號二的電流也相對變小，此時，前饋單元 入轉換單7C 12之電流變化輸出前饋訊號ls。控制單」二 整合回授訊號V。及前饋訊號IS並輪出控制崎cs，= 夂4 低切換開關之責任週期（即降低切換訊號的導通 牛 以減少轉換單元12的輸出功率，進而減少電源單元曰之 輸出功率而與負載裝置L達到平衡。 < :而’上述之脈寬調變技術中，當負載變化如 由重載變為輕載或無載時）’輸入轉換單元η PS的電流也相對變化，但是控制單元Η輸出之控= 早…切換開關導通與截止的切換頻率： :二=成Γ:Γ減少電源控制電路1的元件體 、扪戈J連I百萬赫兹）。因此，當 :固定不嶋成轉換單元12的切換損失相當大刀= k成電源控制電路1的效率降低。 因此’如何提供一種電诉和制 化料文切拖相t 控制電路’可依據負載的變 化為整切換頻率，以降低切換損失 二 電路的效率，已成為重要課題之一。了“電源控制 【發明内容】 有鑑於上述課題，本發明之目的為提供—種可依據負 201230652 载的變化調整切換頻率，以降低切換損失，進而可提高效 率之電源控制電路。 為達上述目的，依據本發明之一種電源控制電路包括 —電源單元、-轉換單H制單元、—前饋單元以及 :頻率線性調整單元。電源單元係輸出—電源訊號。轉換 早X係依據電源訊號產生一驅動訊號。控制單元係產生一 控制訊號以控制轉換單元。前饋單元係依據輸入轉換單元 之電源訊號的電流產生一前馈訊號。頻率線性調整單元係 =虞前饋職產生-解調整訊號，頻率調整訊號輸入控 以控制控制單元之振盪頻率，進而使控制訊號降低 轉換早7C之切換頻率。 在本發明之一實施例中，轉換單元係為返馳式轉換 二順向式轉換器、或升壓式轉換器、或降壓式轉換哭、 降壓式轉換器、或邱克(Cu.k)轉換器、或 =:r、或推挽式轉換器、或全橋式轉換器、 -低一實施例中，前饋單元具有-前饋電阻及 低通;慮波電路，前饋電阻及彳 低通/慮波電路將輪入轉換單 之電源訊號的電流轉換成前饋訊號。 ' 在本發明之一實施例中，轉換單元具有至少— ，控制訊麟藉㈣整切換元件之切換 知凡 轉換單元之切換頻率。 進而控制 办，，本發明之一實施例中，控制單元具有一頻率調 4，頻率調整訊號係輸入頻率調整電容的第一端。 201230652 在本务明之—實施例中 整電容之充電電流，進而降低控制==頻率調 控制訊號降低切換元件之切換頻率。…員率’以使 在本I明之一貫施例中，頻率線性調整單元|古 關元件，前餹邙w 早兀具有一開 : 彻明之-實施例中，開關元件的第:二以 地。 肅連接’開關元件的第三端係電性接 而r低月之一貫施例中’前饋號控制開關元件，進 而降低頻率調整電容的充電電流。 進 二ί發明之一實施例中，切換元件及開關元件係包含 :®電晶體’或場效電晶體、或金屬氧化物半導體 場效電晶體。 切千導體 ^本發明之—實施例中，電源控制電路更包括 回授單元，其係與轉換單元及控制單元電性、，-驅動訊號產生一電壓回授訊號。 亚依據 電舞2發明之一實施例中，電壓回授單元將驅動訊號之 電：轉：，並輸出㈣回授訊號，以使控制訊 凡件的責任週期。 谈 啼明之一實施例中’控制單元係依據頻率調整訊 號、電塵回授訊號及前饋訊號產生控制訊號，以控制切換 元件。 、 j本毛月之貝％例中，當輸入轉換單元之電源訊號 的電飢值越小時’控制單元依據頻率調签訊號使頻率調整 201230652 電谷的充電電流越小，進而使控制訊號控制切換元件之切 換頻率降低越多。 ^承上所述，因依據本發明之電源控制電路之前饋單元 係依據輸入轉換單元之電源訊號的電流產生一前饋吨 號’而頻率線性調整單元係依據前馈訊號產生一頻率調整 訊號，且頻率調整訊號輸入控制單元，以控制控制單元之 振盈頻率。藉此，可依據電源訊號的電流值控制控制單元 2振盤頻率。因此，當負載裝置的負載降低時（例如由重 載變為輕載或無載時），前饋訊號可降低控制單元内之押 制1C的振盪頻率，進而降低轉換單元之切換元件的㈣ 與習知相較，本發明之電源控制電路可依據輸入轉 _、早7L之電源訊號的電流值調整（降低）轉換單元之切 、凡件的切換頻率，故可減少切換元件切換時之暫態損失，、 進而可提高電源控制電路的效率。 【實施方式】 以下將參照相關圖式’說明依本發明較佳 種電源控制電路，其中相同的开杜此，、H 以說明。.J相门的π件將以相同的參照符號加 請同時參照圖2Α及圖2Β所示，其分別為本發明較佳 了之-種電源控制電路2的功能方塊示意圖 負載狀況供應電力給一負載裝置 L例如可4 —家電產品、手機、電腦、全球定位系統（gl0^ 201230652 position system, GPS)、個人行動助理（personal digital assistant, PDA)或其它電子產品。於此，並不加以限制。 電源控制電路2包括一電源單元21、一轉換單元22、 一控制單元23、一前饋單元24、一頻率線性調整單元25 以及一電壓回授單元26。 電源單元21係輸出一電源訊號PS。於此，電源訊號 PS係為一直流訊號。其中，電源單元21可具有固定電壓 準位或可變電壓準位。若為可變電壓準位，其電壓準位例 如可於36伏特至75伏特之間變動。另外，若使用交流電 I 源來驅動負載裝置L，則電源單元21内係包含有整流電 路，使輸出之電源訊號PS為直流電壓訊號。 ; 轉換單元22係與電源單元21電性連接，轉換單元22 . 係依據電源訊號PS產生一驅動訊號DS，以供應負載裝置 L所需的電力。其中，轉換單元22係為一直流轉直流轉換 器（DC-DC Converter )，其例如可為返驰式轉換器、或順 向式轉換器、或升壓式轉換器、或降壓式轉換器、或升/ • 降壓式轉換器、或邱克（Cuk)轉換器、或Sepic轉換器、 或Zeta轉換器、或推挽式轉換器、或全橋式轉換器、或半 橋式轉換器。在本實施例中，轉換單元22係以一返馳式 轉換器為例。 轉換單元22具有至少一切換元件221，而控制單元 23係與轉換單元22之切換元件221電性連接。在本實施 例中，轉換單元22係以具有一切換元件221為例來說明， 然並不以此為限。 201230652 控制單元2 3係產生一控制訊號c s以控制轉換單元u 之切換το件221。其中，控制訊號cs係為一脈寬調變气 號’並可控制切換元件221的導通與截止，以使轉換單元 22依據電源訊號ps輸出驅動訊號ds。 電壓回授單元26係與轉換單元22及控制單元幻電 性連接。電壓回授單元2 6係依據驅動訊號D s輪出一電麼 回授喊VG。在本實施例中，電壓回授單元％具有兩串 聯的電阻R卜R2，使得電壓回授訊號％為驅動訊號恥 的分壓。換言之，電壓回授單元26係將驅動訊號ds之電 壓進行分壓轉換，以輸出電壓回授訊號^。於此，電壓回 授訊號vc的電壓係等於R2 χ Ds/ (R1+R2)。 若驅動訊號DS因負載產生變化而使其電壓準位改變 牯，電壓回授訊號Vc的電壓準位亦相同比例改變。換言 之，當驅動訊號DS之電壓值因負載裝置L的負載變化時， 電壓回授單7G 2 6可依據變化之驅動訊號D s的電壓準位輸 出一電壓回授訊號Vc，並輸入控制單元23。 前馈單元24係依據輸人轉換單元22之電源訊號ps 的電流產生一前饋訊號is ^在本實施例中，前饋單元24 具有一電阻241及一低通濾波電路242。前饋電阻241及 低通濾波電路242係將輸入轉換單元22之電源訊號ps的 電流轉換成前饋訊號IS。於此，輸入轉換單元22之電源 號PS的電流係k入轉換單元22之一變壓元件222的一 次侧線圈，並流經切換元件221及流入前饋單元24之電 阻241，因此，前饋單元24之節點A的電壓^^係與電源 201230652 訊號ps的電流值成正比。電壓Va可建立流經低n皮電 路242的電流’而低通遽波電路242遽除其高頻雜訊後輸 出前饋訊號IS。前饋訊號IS係輸入控制單元幻及頻率線 性調整單元25。 ’ 控制單元23係與轉換單元22、前饋單元24、頻率線 :，調整單元25及電壓回授單元26電性連接。其中，控制 單元^系依據電壓回授訊號％、前饋訊號is及頻率線性 調整單元25產生之-頻率調整訊號以輸出控制訊號cs， 以控制切換兀件221。於此，控制單元23係整合電壓回授 訊號Vc、前饋訊號18及頻率調整訊號FSjt輸出控制訊號 ⑸以控制切換元件221。其中，控制單元23係依據電壓^ 回才又« Vc：及刚饋訊號IS輪出控制訊號cs，以改變切換 凡件221的導通時間（即改變切換元件η的責任週期）， 進而改變轉換單兀22的輸出功率，進而使電源單元2ι的 輸出功率與負載裝置L的電力需求達到平衡。 ^其中，控制單元23具有一頻率調整電容C1、一頻率 =阻R3及一控制器231。其中，控制器231内具有控 率篇二動切換兀件221作動的電路（圖未顯示)。而頻 〜f谷C1及頻率調整電阻幻決定控制器23ι内之控 制1C的振盡頻率。 頻率線性調整單元25係與前饋單元24及控制單元U =連接。頻率線性調整單元25係依據前饋訊號Μ產生 ; 5周整訊號FS，而頻率調整訊號FS係、輸入控制單元23 、k制控制單疋23 °於此’頻率調整訊號FS係輸入控制 201230652 〇〇 /之頻率調整電容231的第一端C11。 在本實施例φ 電路251 ^甲’頻率線性調整單元25係具有一穩壓 ^ τς , 限流電阻252及一開關元件S1。其中，前饋 汛唬IS經穩壓 -.Q1 251穩壓’並藉由限流電阻252與開關 兀件S1的第〜端ςιι + 二端S12 〃 5 M1電性連接。另外，開關元件S1的第 μ μ -'、電性連接頻率調整電容C1之第一端C11，而 開關几件S1 C1 ^ 乐二^ S13係電性接地。其中，開關元件 b JL的第二端$ 乂 2係輸出頻率調整訊號FS，而開關元件S1 的第—端S12係雷岫、击201230652 VI. Description of the Invention: [Technical Field] The present invention relates to a power supply control circuit, and more particularly to a power supply control circuit having a wide modulation. [Prior Art] Pulse (Width) Width M〇dulati〇n (pwM) is a traditional technique in switching, which is to control the V notification between switching elements to achieve the required load requirements. 〇月, ',,, Figure 1, is a functional block diagram of a conventional power supply control circuit 1. Power control circuit! There is a power supply unit u, a conversion buckle 兀12 voltage feedback unit 13, a control unit 14, and a predecessor 15. The power supply unit 11 outputs a power signal Ps. The conversion unit outputs a drive signal DS according to the power signal PS to drive the L. The electric feedback unit 13 outputs a feedback signal according to the change of the driving signal DS (ie, the load of two L, change). The early 7015 is based on the power signal Ps signal 1s of the input conversion unit 12. The control unit 14 outputs a control signal ^ according to the feedback A C or IS to control the switching switch 12 (not shown) to be turned on or off. Wherein, the control number CS can control the duty cycle of the switch (ie, the control conduction time is turned on by the different duty cycle of the switch, so that the drive signal DS of the conversion unit and the load device L can be balanced. For example, when the load When the load of the device L decreases, the voltage of the drive signal still rises 201230652, the voltage feedback unit 13 senses the drive signal (10) and outputs the feedback signal Vc. In addition, the load of the load device L decreases. The current of the input signal unit 2 is relatively small. At this time, the feedforward unit inputs the current change of the conversion unit 7C 12 and outputs the feedforward signal ls. The control unit integrates the feedback signal V and the feedforward. Signal IS and rotates to control the slack cs, = 夂4 low duty switch duty cycle (ie, reduce the turn-on signal of the switching signal to reduce the output power of the conversion unit 12, thereby reducing the output power of the power supply unit and balancing with the load device L < : and 'in the pulse width modulation technique described above, when the load changes from light load to light load or no load) 'the current of the input conversion unit η PS Relative change, but the control unit outputs the control Η = ... early switch is turned off and the switching frequency:: = two to Γ: Γ reduce power circuits of the control element 1, even palpable Ge J I megahertz). Therefore, when the switching loss of the conversion unit 12 is not large, the efficiency of the power supply control circuit 1 is lowered. Therefore, it has become one of the important topics to "provide a kind of electric lawsuit and chemical material cutting phase t control circuit" to change the frequency according to the change of the load to reduce the efficiency of the switching loss circuit. "Power Supply Control" [Invention] In view of the above problems, an object of the present invention is to provide a power supply control circuit that can adjust a switching frequency according to a change of a negative 201230652 load to reduce switching loss and thereby improve efficiency. According to the present invention, a power control circuit includes a power supply unit, a conversion single H unit, a feedforward unit, and a frequency linear adjustment unit. The power unit is an output-power signal. The conversion early X system generates a drive according to the power signal. The control unit generates a control signal to control the conversion unit. The feedforward unit generates a feedforward signal according to the current of the power signal input to the conversion unit. The frequency linear adjustment unit is 虞 front feed generation-demodulation signal, frequency Adjusting the signal input control to control the oscillation frequency of the control unit, thereby reducing the control signal to switch the switching frequency of 7C. In one embodiment of the invention, the conversion unit is a flyback conversion two-way converter, or Compression converter, or buck conversion crying, buck converter, or Qiuk (Cu.k) conversion , or =: r, or push-pull converter, or full-bridge converter, - in the low one embodiment, the feedforward unit has - feedforward resistance and low pass; the wave circuit, feedforward resistance and low The pass/wave circuit converts the current of the power signal that is input into the conversion list into a feedforward signal. In an embodiment of the invention, the conversion unit has at least one, and the control signal is switched by the (four) whole switching element. The switching frequency of the unit. In another embodiment of the present invention, the control unit has a frequency adjustment 4, and the frequency adjustment signal is the first end of the frequency adjustment capacitor. 201230652 In the present invention - the whole capacitor The charging current, and thus the control == frequency adjustment control signal reduces the switching frequency of the switching element. ... the rate of 'in order to make the frequency linear adjustment unit | ancient element in the consistent example of this I, before and after w With an open: in the embodiment - the second and second ground of the switching element are connected to the ground. The third end of the switching element is electrically connected to the low-month consistent embodiment of the 'feedforward number control switching element, Reduce the frequency Adjusting the charging current of the capacitor. In one embodiment of the invention, the switching element and the switching element comprise: a ® transistor or a field effect transistor, or a metal oxide semiconductor field effect transistor. In an embodiment, the power control circuit further includes a feedback unit that is electrically coupled to the conversion unit and the control unit, and generates a voltage feedback signal for the drive signal. According to an embodiment of the invention according to the electric dance 2, the voltage The feedback unit will drive the power of the signal: turn:, and output (4) the feedback signal to control the duty cycle of the control unit. In one embodiment of the discussion, the control unit is based on the frequency adjustment signal and the electric dust feedback signal. And the feedforward signal generates a control signal to control the switching component. In the example of the month of the month, when the power supply signal of the input conversion unit is less, the control unit adjusts the frequency according to the frequency adjustment signal to 201230652. The smaller the charging current of the valley, the more the switching frequency of the control signal control switching element is lowered. According to the present invention, the power supply control circuit according to the present invention generates a feedforward tonne ' based on the current of the power signal of the input conversion unit, and the frequency linear adjustment unit generates a frequency adjustment signal according to the feedforward signal. And the frequency adjustment signal is input to the control unit to control the vibration frequency of the control unit. Thereby, the vibration frequency of the control unit 2 can be controlled according to the current value of the power signal. Therefore, when the load of the load device is reduced (for example, when the heavy load is changed to light load or no load), the feedforward signal can reduce the oscillation frequency of the 1C of the control unit, thereby reducing the (4) of the switching element of the conversion unit. Conventionally, the power control circuit of the present invention can adjust (reduce) the switching unit of the switching unit according to the current value of the input power signal and the power signal of the early 7L, thereby reducing the transient state when the switching element is switched. Loss, and in turn, increases the efficiency of the power control circuit. [Embodiment] Hereinafter, a preferred power supply control circuit according to the present invention will be described with reference to the related drawings, wherein the same is provided, and H is explained. The π-pieces of the J-phase gates will be denoted by the same reference numerals as shown in FIG. 2A and FIG. 2B, respectively, which are respectively a functional block diagram of the power supply control circuit 2 of the present invention. The load device L can be, for example, a home appliance, a mobile phone, a computer, a global positioning system (GPS), a personal digital assistant (PDA), or other electronic products. Here, there is no limitation. The power control circuit 2 includes a power supply unit 21, a conversion unit 22, a control unit 23, a feedforward unit 24, a frequency linearity adjustment unit 25, and a voltage feedback unit 26. The power unit 21 outputs a power signal PS. Here, the power signal PS is a continuous stream signal. The power supply unit 21 can have a fixed voltage level or a variable voltage level. If it is a variable voltage level, its voltage level can vary, for example, between 36 volts and 75 volts. Further, when the AC device 1 is used to drive the load device L, the power supply unit 21 includes a rectifying circuit so that the output power signal PS is a DC voltage signal. The conversion unit 22 is electrically connected to the power unit 21, and the conversion unit 22 generates a driving signal DS according to the power signal PS to supply the power required by the load device L. The conversion unit 22 is a DC-DC converter, which may be, for example, a flyback converter, a forward converter, or a boost converter, or a buck converter. Or a / buck converter, or a Cuk converter, or a Sepic converter, or a Zeta converter, or a push-pull converter, or a full-bridge converter, or a half-bridge converter. In the present embodiment, the conversion unit 22 is exemplified by a flyback converter. The conversion unit 22 has at least one switching element 221, and the control unit 23 is electrically connected to the switching element 221 of the conversion unit 22. In the present embodiment, the conversion unit 22 is described by taking a switching element 221 as an example, but is not limited thereto. 201230652 The control unit 2 3 generates a control signal c s to control the switching τ 221 of the conversion unit u. The control signal cs is a pulse width modulation gas number and can control the on and off of the switching element 221, so that the conversion unit 22 outputs the driving signal ds according to the power signal ps. The voltage feedback unit 26 is phantomically connected to the conversion unit 22 and the control unit. The voltage feedback unit 26 outputs a call according to the drive signal D s. In this embodiment, the voltage feedback unit % has two series-connected resistors R, R2, such that the voltage feedback signal % is the partial pressure of the driving signal shame. In other words, the voltage feedback unit 26 divides and converts the voltage of the driving signal ds to output a voltage feedback signal ^. Here, the voltage of the voltage feedback signal vc is equal to R2 χ Ds / (R1 + R2). If the driving signal DS changes its voltage level due to a change in load, the voltage level of the voltage feedback signal Vc also changes in the same proportion. In other words, when the voltage value of the driving signal DS changes due to the load of the load device L, the voltage feedback sheet 7G 26 can output a voltage feedback signal Vc according to the voltage level of the changed driving signal D s and input to the control unit 23 . . The feedforward unit 24 generates a feedforward signal is according to the current of the power signal ps of the input conversion unit 22. In the embodiment, the feedforward unit 24 has a resistor 241 and a low pass filter circuit 242. The feedforward resistor 241 and the low pass filter circuit 242 convert the current of the power signal ps input to the conversion unit 22 into a feedforward signal IS. Here, the current of the power source number PS of the input conversion unit 22 is input to the primary side coil of the transformer element 222 of the conversion unit 22, and flows through the switching element 221 and the resistor 241 flowing into the feedforward unit 24, thus, feedforward The voltage of node A of unit 24 is proportional to the current value of power supply 201230652 signal ps. The voltage Va establishes a current flowing through the low n-th circuit 242, and the low-pass chopper circuit 242 outputs the high-frequency noise to output the feedforward signal IS. The feedforward signal IS is an input control unit magic and frequency linearity adjustment unit 25. The control unit 23 is electrically connected to the conversion unit 22, the feedforward unit 24, the frequency line:, the adjustment unit 25, and the voltage feedback unit 26. The control unit ^ controls the switching element 221 according to the voltage feedback signal %, the feedforward signal is, and the frequency adjustment signal generated by the frequency linear adjustment unit 25 to output the control signal cs. Here, the control unit 23 integrates the voltage feedback signal Vc, the feedforward signal 18, and the frequency adjustment signal FSjt to output a control signal (5) to control the switching element 221. The control unit 23 rotates the control signal cs according to the voltage return and the Vc: and the feed signal IS to change the on-time of the switching component 221 (ie, change the duty cycle of the switching element η), thereby changing the conversion list. The output power of the crucible 22, in turn, balances the output power of the power supply unit 2i with the power demand of the load device L. ^ The control unit 23 has a frequency adjustment capacitor C1, a frequency = resistance R3, and a controller 231. The controller 231 has a circuit (not shown) for controlling the second-moving switching element 221 to operate. The frequency ~f valley C1 and the frequency adjustment resistor magically determine the oscillation frequency of the controller 1C within the control unit 23i. The frequency linearity adjustment unit 25 is connected to the feedforward unit 24 and the control unit U=. The frequency linearity adjusting unit 25 generates the signal according to the feedforward signal ;; the 5-week integer signal FS, and the frequency adjustment signal FS system, the input control unit 23, and the k-control unit 23°. The frequency adjustment signal FS system input control 201230652 〇 The frequency of 〇/ adjusts the first end C11 of the capacitor 231. In the present embodiment, the φ circuit 251 ^ A ' frequency linear adjustment unit 25 has a voltage regulator ^ τ , a current limiting resistor 252 and a switching element S1. The feedforward 汛唬IS is regulated by the voltage regulator -.Q1 251 and is electrically connected to the second end S12 〃 5 M1 of the switch element S1 by the current limiting resistor 252. In addition, the μ μ -' of the switching element S1 is electrically connected to the first end C11 of the frequency adjustment capacitor C1, and the switches S1 C1 ^Le2^S13 are electrically grounded. Wherein, the second end $ 乂 2 of the switching element b JL outputs a frequency adjustment signal FS, and the first end S12 of the switching element S1 is a thunder and a strike
因此 ^ 示包〖生連接頻率調整電容C1的第一端C11。 別饋#號IS係可控制頻率線性調整單元25輸出頻 率調整1 ° 以控制頻率調整電容Cl的充電電流，使 控制器231 Μ + & μ τ 〇 ^之控制1C的振盪頻率改變，進而使控制訊 说CS控制轉換單元22之切換元件221的切換頻率。 其中’切換元件221及開關元件S1係可分別為雙載 子接面龟晶體（Bipolar Junction Transistor，BJT )，或場效Therefore, the first connection C11 of the capacitor C1 is connected. Do not feed #号IS system control frequency linear adjustment unit 25 output frequency adjustment 1 ° to control the charging current of the frequency adjustment capacitor C1, so that the oscillation frequency of the control 1C of the controller 231 & + & μ τ 〇 ^ is changed, thereby The control signal CS controls the switching frequency of the switching element 221 of the conversion unit 22. Wherein the switching element 221 and the switching element S1 are respectively Bipolar Junction Transistor (BJT), or field effect
電晶體（Field Effect Transistor,FET)、或金屬氧化物半導 體场效電晶體（Metal-Oxide-Semiconductor Field-Effect Transistor，M0SFET)。在本實施例中，切換元件221係以 金屬氧化物半導體場效電晶體為例，而開關元件S1係以 PNP型之雙載子接面電晶體為例。然並不以此為限制。 請再參照圖2B所示，以進一步說明頻率線性調整單 元25係如何控制頻率調整電容C1的充電電流。 當負載裝置L的負載改變時，例如由重載變為輕載， 驅動訊號DS的電流降低，進而使輸入轉換單元22之電源Field Effect Transistor (FET), or Metal-Oxide-Semiconductor Field-Effect Transistor (M0SFET). In the present embodiment, the switching element 221 is exemplified by a metal oxide semiconductor field effect transistor, and the switching element S1 is exemplified by a PNP type double carrier junction transistor. However, this is not a limitation. Referring again to Fig. 2B, it is further explained how the frequency linearity adjusting unit 25 controls the charging current of the frequency adjusting capacitor C1. When the load of the load device L changes, for example, from a heavy load to a light load, the current of the drive signal DS is lowered, thereby further powering the input conversion unit 22.
S 12 201230652 訊號ps的電流降低，因此，流經轉換單元22之變壓元件 222 —次側線圈的電流亦降低，造成前饋單元24之節點A 的電壓Va亦降低。於此，節點A的電壓VA與輸入轉換單 兀22之電源訊號PS的電流值係成正比例降低。反之亦然。 當負載變低而使節點A的電壓Va降低時，輸入頻率 線性調整單元25之前饋訊號IS的電壓亦降低，而前饋訊 唬is輸入頻率線性調整單元25之開關元件si的第一端 曰之電流亦相對降低。纟開關元件S1 (本實施例為PNp Φ 電晶體）之特性可知，流入開關元件S1的第一端S11之 1流降低時’將使由開關元件si之第二端S12流入第三 立而S13的電流工升高。於此，輸入開關元件第一端川 :之電流可控制開關元件S1的導通比例，使電流j經由開關 :兀件幻的第二端S12流向第三端S13。因此，原本流入頻 率魏電合C1的第-端cu之充電電流的―部分將被> 流’並由開關元件81的第二端S12流向第三端sn，使得 流入頻率調整電容C1的充電電流減少。流入頻率 =的=電流減少時，將使頻率調整電容C" =加=而可降^空制器231内之控制10的振盡頻率: 二？ 過控制早70 23輸出之控制訊號CS控制切換元 件21的切換頻率。若降低切換元件221的切換頻率，、即 可降低切換7L件221導通與截 換元件瓜切換時之暫 =刀換_人數’故可減少切 的損耗並提升效率。…進而降低電源控制電路2 因此，電源控制電路2可依據輪入轉換單元U之電 13 201230652 源訊號ps的電流控制轉換 頻率。μ ^ 之切換70件221的切換 頸早另外，當負載裝置L由重載+ 饋訊號IS可藉由Λ載夂為㈣或無載時’前 j It由斜錄㈣單元25大幅降低控制單元 =1IC:振盪頻率，進而降低轉換單元22之術 件221的切換損失。 之電的是，因節點A0_Va係與電源訊號PS 之電机成正比，且輸入開關元件si第一端川 控制開關元件si的逡、s , :S1的導通比例。因此，本發明之頻率線性 °。早 係可線性地調整切換元件221的切換頻率。 另外’本發明之電源控制電路2之初始元件參數的設計係 =㈣載裝置L為重載情況下。因此，當負载襄置：為The current of the S 12 201230652 signal ps is reduced, so that the current flowing through the transformer element 222 of the conversion unit 22 - the current of the secondary side coil is also lowered, causing the voltage Va of the node A of the feedforward unit 24 to also decrease. Here, the voltage VA of the node A is proportional to the current value of the power signal PS of the input conversion unit 22. vice versa. When the load is low and the voltage Va of the node A is lowered, the voltage of the feed signal IS before the input frequency linearity adjusting unit 25 is also lowered, and the feedforward signal is input to the first end of the switching element si of the frequency linearity adjusting unit 25. The current is also relatively reduced. The characteristic of the 纟 switching element S1 (the PNp Φ transistor in this embodiment) is that when the current flowing into the first end S11 of the switching element S1 is lowered, 'the second end S12 of the switching element si will flow into the third vertical S13. The current is increased. Here, the current of the input switching element first end can control the conduction ratio of the switching element S1, so that the current j flows to the third end S13 via the second end S12 of the switch. Therefore, the portion of the charging current of the first end cu of the inflow frequency Wei C1 will be > flow 'and flow from the second end S12 of the switching element 81 to the third end sn, so that the charging of the inflow frequency adjusting capacitor C1 The current is reduced. When the inflow frequency = = current decreases, the frequency adjustment capacitor C" = plus = can be reduced to the oscillation frequency of the control 10 in the air conditioner 231: The control signal CS that controls the output of the early 70 23 controls the switching frequency of the switching element 21. If the switching frequency of the switching element 221 is lowered, the switching of the 7L member 221 and the temporary switching of the switching element can be reduced, thereby reducing the cutting loss and improving the efficiency. ...and thus the power control circuit 2 is lowered. Therefore, the power supply control circuit 2 can control the switching frequency according to the current of the source signal ps which is turned into the conversion unit U. The switching neck of the 70 221 of the μ ^ switch is different. When the load device L is overloaded + the feed signal IS can be used as the (4) or no load, the front control unit is greatly reduced by the slanting (four) unit 25 =1IC: The oscillation frequency, which in turn reduces the switching loss of the workpiece 221 of the conversion unit 22. The electric power is that the node A0_Va is proportional to the motor of the power signal PS, and the first switching port of the input switching element si controls the conduction ratio of 逡, s, :S1 of the switching element si. Therefore, the frequency of the present invention is linear °. The switching frequency of the switching element 221 can be adjusted linearly as early as possible. Further, the design of the initial component parameters of the power supply control circuit 2 of the present invention = (4) The carrier device L is in the case of heavy load. So when the load is set: for
滿載^電源訊號PS之電流越高，前饋單元24之節點A 的電壓vA亦越高，使得輸入開關元件si的第—端 電流越低。 ' ^疋，虽負載裝置L由重載變為輕載或無載時，輸入 轉換早το 22之電源訊號ps的電流值越小，使得前饋單元 2/之節點A的電壓Va亦越小，造成流入開關元件w之 =一端sii的電流亦越大，使得開關元件S1導通比例越 向，故由開關元件S1之第二端S12流入第三端Sl3的電 流I越大。因此，流入頻率調整電容C1的充電電流越小， 其充電時間越長，進而使控制訊號23控制切換元件 之切換頻率降低越多，因此，電源控制電路2的切換的損 耗將更低。當負載越低時，與習知電路相較，電源控制電 路2的效率將可提升更多。The higher the current of the full load power signal PS, the higher the voltage vA of the node A of the feedforward unit 24, so that the lower end current of the input switching element si is lower. ' ^疋, although the load device L changes from heavy load to light load or no load, the smaller the current value of the power signal ps of the input conversion early το 22, the smaller the voltage Va of the node A of the feedforward unit 2/ The current flowing into the one end sii of the switching element w is also larger, so that the conduction ratio of the switching element S1 is higher, so that the current I flowing from the second end S12 of the switching element S1 to the third end S13 is larger. Therefore, the smaller the charging current flowing into the frequency adjusting capacitor C1, the longer the charging time, and the more the switching frequency of the control signal 23 is controlled by the control signal 23, so that the switching of the power supply control circuit 2 will be lower. The lower the load, the more efficient the power control circuit 2 will be compared to conventional circuits.
S 14 201230652 ^ 上所述，因依據本發明之電源控制電路之前饋單元 係依據輸入轉換單几之電源訊號的電流產生一前饋訊 號。，而頻率線性調整單元係依據前饋訊號產生一頻率調整 祝號’且頻率調整訊號輸入控制單元，以控制控制單元之 振盪頻率。藉此，可依據電源訊號的電流值控制控制單元 員率。因此，當負载裝置的負載降低時(例如由重 之㈣^ J饋3孔號可大幅降低控制單元内 之:们C的振竭’進而降低轉換 切換損”與習知相較，本發明之電源控制電路 入:換早兀之電源訊號的電流值調整（ ： :失，進而可提南電源控制電路的效率。 〜貝 :卩上料料舉舰，㈣為_性者。任 本發明之精神與範田壽，而對其進行之 :未脫離 應包含於後附之申請專利範圍中。 ，文或免更’均 •【圖式簡單說明】 =1習知-種電源控制電路的功能方塊圖； 圖2Λ為本發明較佳實施例之—種 能方塊示意 圖；以及$ ^ —種電源控制電路的功 路示意圖 圖2B為本發明較佳實施例之— 圖。 你徑制電路的電 【主要元件符號說明】 201230652 I、 2 :電源控制電路 II、 21 :電源單元 12、 22 :轉換單元 13、 26:電壓回授單元 14、 23 :控制單元 15、 24 :前饋單元 221 :切換元件 222 :變壓元件 231 :控制器 _ 241、252、Rl、R2、R3 :電阻 242 :低通濾波電路 25 :頻率線性調整單元 251 :穩壓電路 A :節點 C1 :頻率調整電容 CH、S1 卜 S12、S13 :端 CS:控制訊號 籲 D S :驅動訊號 FS:頻率調整訊號 I :電流 IS :前饋訊號 L :負載裝置 PS :電源訊號 S1 :開關元件S 14 201230652 ^ As described above, the feed control unit of the power control circuit according to the present invention generates a feedforward signal according to the current of the power signal of the input conversion unit. And the frequency linear adjustment unit generates a frequency adjustment command ' according to the feedforward signal and the frequency adjustment signal is input to the control unit to control the oscillation frequency of the control unit. Thereby, the control unit rate can be controlled according to the current value of the power signal. Therefore, when the load of the load device is lowered (for example, by the weight of the (3), the 3 hole number can greatly reduce the depletion of the C in the control unit, thereby reducing the switching switching loss, and the present invention is compared with the conventional one. The power control circuit is input: the current value of the power signal is changed earlier (:: loss, and then the efficiency of the power control circuit of the south can be raised. ~Bei: the material is lifted on the raft, and (4) is _ sex. Any of the inventions Spirit and Fan Tianshou, and carry it out: not to be excluded from the scope of the patent application attached to the following., text or exemption 'all • [schematic description] =1 conventional - the function of the power control circuit FIG. 2 is a schematic diagram of an energy square according to a preferred embodiment of the present invention; and FIG. 2B is a schematic diagram of a power path of a power control circuit. FIG. 2B is a diagram of a preferred embodiment of the present invention. [Description of main component symbols] 201230652 I, 2: power supply control circuit II, 21: power supply unit 12, 22: conversion unit 13, 26: voltage feedback unit 14, 23: control unit 15, 24: feedforward unit 221: switching Element 222: Transformer Element 231: Controller _ 241, 252, Rl, R2, R3: Resistor 242: Low-pass filter circuit 25: Frequency linearity adjustment unit 251: Voltage regulator circuit A: Node C1: Frequency adjustment capacitor CH, S1 Bu S12, S13: Terminal CS: Control signal DS: Drive signal FS: Frequency adjustment signal I: Current IS: Feedforward signal L: Load device PS: Power signal S1: Switching element
S 16 201230652 v、v A :電壓 vc:電壓回授訊號S 16 201230652 v, v A : voltage vc: voltage feedback signal