和 5093 五、新型說明： 【新型所屬之技術領域】 [0001] 本創作是有關於一種電源供應器，且特別是有關於 一種具有過壓保護的電源供應器。 【先前技術】 [0002] 圖1為一種現有的電源供應器的部分電路圖。請參見 圖1，電源供應器1通過交流電源線10接收交流電源Vin並 將其轉換為穩定的直流電壓Vbus，以供後續如直流至直 φ 流轉換器轉換成不同準位的直流電壓。電源供應器1包括 電磁干擾（ElectroMagnetic Interference，EMI) 遽波器11、橋式整流器1 2、功率因數修正器（powerAnd 5093 V. New Description: [New Technology Field] [0001] This creation is related to a power supply, and in particular to a power supply with overvoltage protection. [Prior Art] [0002] FIG. 1 is a partial circuit diagram of a conventional power supply. Referring to Fig. 1, the power supply 1 receives the AC power supply Vin through the AC power line 10 and converts it into a stable DC voltage Vbus for subsequent DC voltage conversion to a different level, such as a DC to DC converter. The power supply 1 includes Electromagnetic Interference (EMI) chopper 11, bridge rectifier 1 2, power factor corrector (power
Factor Corrector，PFC) 13 及電解電容器 14。EMI 遽 波器11包括安規電容器C1及共模電感器Li，用於抑制電 磁雜訊通過交流電源線10傳入或傳出電源供應器1 ^橋式 整流器12包括二極體D1〜D4，用於將交流電源Vin整流 為脈動直流電壓。PFC 13為升壓型PFC，其包括作為開 關的電晶體Q1、電感器L2及二極體D5，用於改善因橋式 整流器12所造成交流電源Vin輸入的電流畸形，以提高功 率因數。電解電容器14用於濾除脈動直流電壓中的交流 成分以輸出穩定的直流電壓Vbus。 [0003] 電解電容器14通常採用鋁質電解電容器，因其具有 價格便宜、容量大及耐壓值高的優點而被廣泛應用於各 種電器中。不過，目前鋁質電解電容器多採用易燃的有 機酸作為電解液，於工作時兩鋁箔間會匯聚大量的靜電 能量’當靜電能量達到崩潰,點或產生極間短路飛弧時， 10120699#單編號第3頁/共24頁 1012022904-0 M435093 極有可能發生爆炸或起火。例如，輸入的交流電源Vina 現數個週期的電壓突波，或者PFC 13因迴授不良導致開 關導通時間或責任週期增大而造成其輸出電壓升高，最 終都會影響到電解電容器1 4兩端的跨壓（即直流電壓 V bus)升高，使兩銘箔間快速匯聚大量靜電能量而極有 可能發生爆炸或起火。 [0004] 為了避免鋁質電解電容器在爆炸或起火時發生延燒 而產生危害，多家廠商先後提出具有阻燃特性的鋁電解 電容器，但其僅能在爆炸或起火時避免延燒的發生，並 不會對電容器本體可允許的最大跨壓有所提升，因此當 電容器的跨壓發生異常而超過其最大跨壓時，阻燃鋁電 解電容器仍然會損壞，這對於市場不良率並沒有直接的 改善，加上其價格昂貴，因而鮮少被一般設計所採用。 【新型内容】 [0005] 有鑑於此，本創作的目的在提出一種具有過壓保護 的電源供應器，可防止電解電容器爆炸或起火，以避免 電解電容器在爆炸或起火時發生延燒而產生危害。 [0006] 為達到上述目的或其它目的，本創作提出一種具有 過壓保護的電源供應器，包括繼電器、交流至直流轉換 器、電解電容器、電壓偵測器、磁滯比較器及驅動電路 。其中，繼電器包括開關單元及控制單元，開關單元耦 接於交流電源及交流至直流轉換器之間，控制單元控制 開關單元導通或斷開。交流至直流轉換器將接收到的交 流電源整流為脈動直流電壓。電解電容器將接收到的脈 動直流電壓濾波為直流電壓。電壓偵測器偵測電解電容 10120699^^^^ A〇101 第4頁/共24頁 1012022904-0 M435093 » » 器的跨壓以輸出相應的偵測電壓。磁滯比較器耦接於電 壓偵測器及驅動電路之間，磁滯比較器根據偵測電壓在 電解電容器的跨壓上升至大於上限門檻值時通過驅動電 路驅動控制單元控制開關單元由導通變成斷開，並在電 解電容器的跨壓下降至小於下限門檻值時通過驅動電路 驅動控制單元控制開關單元由斷開變成導通。 [0007] 在一實施例中，控制單元包括線圈，且驅動電路包 括圖騰柱電路。磁滯比較器在電解電容器的跨壓上升至 大於上限門檻值時輸出的控制信號由第一準位變成第二 準位，具有第二準位的控制信號使圖騰柱電路產生電流 ，電流流過線圈而激磁以控制常閉型（norma 11 y closed)的開關單元斷開。磁滯比較器在電解電容器的 跨壓下降至小於下限門檻值時輸出的控制信號由第二準 位變成第一準位，具有第一準位的控制信號使圖騰柱電 路不產生電流而使線圈停止激磁以控制常閉型的開關單 元恢復導通。 · [0008] 在一實施例中，控制單元包括設定線圈及重置線圈 ，且驅動電路包括第一單穩態多諧振盪器及第二單穩態 多諧振盪器。磁滯比較器在電解電容器的跨壓上升至大 於上限門檻值時輸出的控制信號由第一準位變成第二準 位，由第一準位變成第二準位的轉換觸發第一單穩態多 諧振盪器產生第一脈衝信號，第一脈衝信號驅動設定線 圈控制開關單元由導通變成斷開。磁滯比較器在電解電 容器的跨壓下降至小於下限門檻值時輸出的控制信號由 第二準位變成第一準位，由第二準位變成第一準位的轉 10120699#單編號 A0101 第5頁/共24頁 1012022904-0 [0009]M435093 換觸發第二單穩態多諧振盪器產生第二脈衝信號，第二 脈衝信號驅動重置線圈控制開關單元由斷開變成導通。 本創作因採用直接偵測電解電容器的跨壓，在偵測 到電解電容器的跨壓發生異常但尚未超過其最大跨壓時 通過繼電器立即切斷交流電源輸入，並在異常消失後通 過繼電器重新接回交流電源，因此不論是輸入的交流電 源電壓出現異常突波或是PFC迴授異常產生的電壓升高均 不會影響到電解電容器，可防止電解電容器爆炸或起火 ，以避免電解電容器在爆炸或起火時發生延燒而產生危 害。此外，在電解電容器的跨壓的偵測上制訂出上、下 限門檻值以作為繼電器切斷或接回交流電源的依據，如 此可抑制雜訊的干擾，確保繼電器不會誤動作或臨界彈 跳。 [0010] 為讓本創作之上述和其他目的、特徵和優點能更明 顯易懂，下文特舉較佳實施例，並配合所附圖式，作詳 細說明如下。 【實施方式】 [0011] 圖2為根據本創作一實施例的電源供應器的部分電路 圖。請參見圖2，電源供應器2通過交流電源線20接收交 流電源Vin並將其轉換為穩定的直流電壓Vbus，以供後續 如直流至直流轉換器轉換成不同準位的直流電壓，而且 電源供應器2具有針對電解電容器的過壓保護功能，可防 止電解電容器爆炸或起火，以避免電解電容器在爆炸或 起火時發生延燒而產生危害。電源供應器2包括EMI濾波 器21、交流至直流轉換器（包括橋式整流器22及PFC 23 10120699^^ A0101 第6頁/共24頁 1012022904-0 M435093 • » )、電解電容器24、繼電器25、電壓偵測器26、磁滯比 較器27、驅動電路28及參考電壓產生器29。其中，EMI 濾波器21、橋式整流器22及PFC 23可以採用如圖1所示 的EMI瀘波器1Ϊ、橋式整流器12及PFC 13，在此不再贅 述其構成與功能，而電解電容器24可以採用一般鋁質電 解電容器。 [0012] 繼電器25包括開關單元251及控制單元252。開關單 元251耦接於交流電源Vin及EMI濾波器21之間，而控制 單元252利用磁力控制開關單元251導通或斷開。當開關 單元251導通時，允許輸入的交流電源Vin傳送到EMI濾 波器21。當開關單元251斷開時，不允許交流電源Vin傳 送到EM I濾波器21，即切斷交流電源V i η輸入。但本實施 例並非用於限制本創作，例如，開關單元251可以改成耦 接於ΕΜΙ濾波器21及橋式整流器22之間。 [0013] 電壓偵測器26耦接於電解電容器24的兩端之間，用 於偵測電解電容器24的跨壓（即直流電壓Vbus)以輸出 相應的偵測電壓Vsen。在本實施例中，電壓偵測器26包 括電阻器R1和R2，電阻器R1和R2串聯耦接於電解電容器 24的兩端之間，電阻器R1和R2的共同端點輸出與電解電 容器24的跨壓Vbus相應的偵測電壓Vsen，其中，Vsen =R2ARl+R2)xVbus。 [0014] 磁滯比較器27耦接於電壓偵測器26及驅動電路28之 間。磁滯比較器27根據偵測電壓Vsen在電解電容器24的 跨壓Vbus上升至大於上限門檻值時，即在電解電容器24 的跨壓Vbus發生異常但尚未超過其最大跨壓時，通過驅 10120699产單織删1 第7頁/共24頁 1012022904-0 M435093 動電路28驅動控制單元252控制開關單元251由導通變成 斷開，以便立即切斷交流電源Vin輸入。另外，磁滯比較 器27根據偵測電壓vsen在電解電容器24的跨壓Vbus下降 至小於下限門檻值時，即在電解電容器24的跨壓Vbus* 發生的異常消失時，通過驅動電路28驅動控制單元252控 制開關單元251由斷開變成導通，以便重新接回交流電源 Vin。藉由磁滯比較器27在電解電容器24的跨壓Vbus的 偵測上制訂出上、下限門檻值以作為繼電器25的開關單 元251導通或斷開的依據，如此可抑制雜訊的干擾，確保 繼電器25不會誤動作或臨界彈跳。在一實施例中，交流 電源Vin可以為90Vac〜264Vac，PFC 23的輸出電厘可 以設計為400V左右，此時上、下限門播值可以分別設計 為570V及380V。 [0015] 在本實施例中，磁滯比較器27為反相磁滯比較器， 其包括運异放大器OP1及電阻器R3和R4，且運算放大器 OP1由内部產生的穩定的直流電壓Vcc所供電。磁滞比較 器 27 提供高臨界值 Vth = R4/(R3+R4)xVi*ef + R3/(R3+R4)xVcc ’ 低臨界值Vtl = R4/(R3 + R4)xVref -R3/(R3+R4)xVcc。磁滯比較器27在偵測電壓vsen上 升至大於高臨界值Vth時，表示電解電容器24的跨壓 Vbus上升至大於上限門檻值Vth’ ，故輸出的控制信號 Vctl由第一準位VI變成第二準位V0，具有第二準位v〇的 控制信號Vet 1通過驅動電路28驅動控制單元252控制開 關早元2 51由導通變成斷開。另外，磁滯比較器2 7在偵測 電壓Vsen下降至小於低臨界值Vtl時，表示電解電容器 ，故輸出的 1012022904-0 24的跨壓Vbus下降至小於下限門捏值vtl， 10120699#單編號A01〇l 第8頁/共24頁 M435093 控制信號Vctl由第二準位VO變成第一準位V1，具有第— 準位VI的控制信號Vct 1通過驅動電路28驅動控制單元 252控制開關單元251由斷開變成導通。其中，上限門檀 值Vth’ = (Rl+R2)/R2xVth ’ 下限門檻值vtl，= (Rl+R2)/R2xVtl 。 [0016] 因此，可通過調整參考電麼Vref及電阻器R3和R4來 設計磁滯比較器27提供的高 '低臨界值vth和Vtl，進而 在電解電容器24的跨壓Vbus的偵測上制訂出上、下限門 檻值Vth’和Vtl’ 。而參考電壓Vref可以由參考電壓產 生器29所提供’此參考電壓產生器29包括並聯穩壓器（ shunt regulator) U1、電阻器R5及電容器C2。若採用 號TL431的並聯穩壓器U1 ’則參考電壓為穩定的 2. 5V «Factor Corrector, PFC) 13 and electrolytic capacitors 14. The EMI chopper 11 includes a safety capacitor C1 and a common mode inductor Li for suppressing electromagnetic noise from being transmitted to or from the power supply through the AC power line 10. The bridge rectifier 12 includes diodes D1 to D4. The AC power source Vin is rectified to a pulsating DC voltage. The PFC 13 is a boost type PFC, which includes a transistor Q1 as a switch, an inductor L2, and a diode D5 for improving the current distortion of the AC power source Vin input caused by the bridge rectifier 12 to improve the power factor. The electrolytic capacitor 14 is for filtering out the AC component in the pulsating DC voltage to output a stable DC voltage Vbus. The electrolytic capacitor 14 is usually made of an aluminum electrolytic capacitor and is widely used in various electric appliances because of its advantages of low cost, large capacity, and high withstand voltage. However, at present, aluminum electrolytic capacitors mostly use flammable organic acids as electrolytes, and a large amount of electrostatic energy is concentrated between the two aluminum foils during operation. When the electrostatic energy reaches a collapse, when a point or an inter-pole short-circuit arc occurs, 10120699# No. Page 3 of 24 1012022904-0 M435093 It is highly probable that an explosion or fire will occur. For example, the input AC power supply Vina has several cycles of voltage surge, or the PFC 13 causes the switch's conduction time or duty cycle to increase due to poor feedback, which causes the output voltage to rise, which will eventually affect the ends of the electrolytic capacitor 14. The voltage across the voltage (ie, the DC voltage Vbus) rises, causing a large amount of electrostatic energy to quickly converge between the two foils, which is highly likely to explode or ignite. [0004] In order to avoid the hazard of aluminum electrolytic capacitors from being burned during explosion or fire, many manufacturers have proposed aluminum electrolytic capacitors with flame retardant properties, but they can only avoid the occurrence of burning during explosion or fire, and The maximum allowable cross-over voltage of the capacitor body is improved. Therefore, when the cross-voltage of the capacitor is abnormal and exceeds its maximum cross-voltage, the flame-retardant aluminum electrolytic capacitor will still be damaged, which has no direct improvement on the market defect rate. In addition to its high price, it is rarely used by general design. [New content] [0005] In view of this, the purpose of this creation is to propose a power supply with overvoltage protection to prevent the electrolytic capacitor from exploding or igniting, so as to avoid the occurrence of damage caused by the explosion of the electrolytic capacitor in the event of an explosion or fire. In order to achieve the above object or other objects, the present invention proposes a power supply with overvoltage protection, including a relay, an AC to DC converter, an electrolytic capacitor, a voltage detector, a hysteresis comparator, and a driving circuit. The relay includes a switch unit and a control unit. The switch unit is coupled between the AC power source and the AC to DC converter, and the control unit controls the switch unit to be turned on or off. The AC to DC converter rectifies the received AC power to a pulsating DC voltage. The electrolytic capacitor filters the received pulsating DC voltage to a DC voltage. The voltage detector detects the electrolytic capacitor 10120699^^^^ A〇101 Page 4 of 24 1012022904-0 M435093 » The voltage across the device is used to output the corresponding detection voltage. The hysteresis comparator is coupled between the voltage detector and the driving circuit, and the hysteresis comparator controls the switching unit to be turned on by the driving circuit driving control unit according to the detecting voltage when the voltage across the electrolytic capacitor rises to be greater than the upper threshold value. Disconnected, and when the voltage across the electrolytic capacitor drops to less than the lower threshold value, the control unit drives the control unit to change from off to on. In an embodiment, the control unit includes a coil and the drive circuit includes a totem pole circuit. The hysteresis comparator changes the control signal outputted from the first level to the second level when the voltage across the electrolytic capacitor rises to a value greater than the upper threshold. The control signal having the second level causes the totem pole circuit to generate a current, and the current flows. The coil is energized to control the switching of the normally closed (norma 11 y closed) switching unit. The hysteresis comparator changes the control signal outputted from the second level to the first level when the voltage across the electrolytic capacitor drops to less than the lower threshold value, and the control signal having the first level causes the totem pole circuit to generate no current to cause the coil The excitation is stopped to control the normally closed switching unit to resume conduction. [0008] In an embodiment, the control unit includes a set coil and a reset coil, and the drive circuit includes a first monostable multivibrator and a second monostable multivibrator. The hysteresis comparator outputs a control signal when the voltage across the electrolytic capacitor rises above the upper threshold value from the first level to the second level, and the transition from the first level to the second level triggers the first monostable state. The multivibrator generates a first pulse signal, and the first pulse signal drives the set coil to control the switching unit to be turned off from on. The hysteresis comparator converts the control signal outputted when the voltage across the electrolytic capacitor drops to less than the lower threshold value from the second level to the first level, and the second level becomes the first level. 10120699# single number A0101 5 pages / total 24 pages 1012022904-0 [0009] M435093 The triggering second monostable multivibrator generates a second pulse signal, and the second pulse signal drives the reset coil to control the switching unit to become conductive from off. Due to the direct detection of the cross-voltage of the electrolytic capacitor, the creation immediately cuts off the AC power input through the relay when it detects that the cross-voltage of the electrolytic capacitor is abnormal but has not exceeded its maximum cross-voltage, and reconnects it through the relay after the abnormal disappearance. Back to the AC power supply, so whether the abnormal voltage of the input AC power supply voltage or the voltage rise caused by the PFC feedback abnormality will not affect the electrolytic capacitor, it can prevent the electrolytic capacitor from exploding or igniting to avoid the electrolytic capacitor exploding or A fire occurs when a fire occurs and a hazard occurs. In addition, the upper and lower thresholds are set on the detection of the cross-voltage of the electrolytic capacitor as the basis for the relay to cut off or connect back to the AC power supply, so as to suppress the interference of the noise and ensure that the relay does not malfunction or critically jump. The above and other objects, features, and advantages of the present invention will become more apparent from the description of the appended claims. [Embodiment] FIG. 2 is a partial circuit diagram of a power supply according to an embodiment of the present invention. Referring to FIG. 2, the power supply 2 receives the AC power supply Vin through the AC power line 20 and converts it into a stable DC voltage Vbus for subsequent DC voltage conversion to a different level, such as a DC-to-DC converter, and the power supply. The device 2 has an overvoltage protection function for the electrolytic capacitor, which prevents the electrolytic capacitor from exploding or igniting, thereby preventing the electrolytic capacitor from being burned in the event of an explosion or a fire. The power supply 2 includes an EMI filter 21, an AC to DC converter (including a bridge rectifier 22 and a PFC 23 10120699^^ A0101 page 6/24 pages 1012022904-0 M435093 • »), an electrolytic capacitor 24, a relay 25, The voltage detector 26, the hysteresis comparator 27, the drive circuit 28, and the reference voltage generator 29. The EMI filter 21, the bridge rectifier 22 and the PFC 23 can adopt the EMI chopper 1 Ϊ, the bridge rectifier 12 and the PFC 13 as shown in FIG. 1 , and the configuration and functions thereof will not be described herein, and the electrolytic capacitor 24 will be omitted. A general aluminum electrolytic capacitor can be used. [0012] The relay 25 includes a switching unit 251 and a control unit 252. The switching unit 251 is coupled between the AC power source Vin and the EMI filter 21, and the control unit 252 is turned on or off by the magnetic force control switch unit 251. When the switching unit 251 is turned on, the input AC power source Vin is allowed to be transmitted to the EMI filter 21. When the switching unit 251 is turned off, the AC power source Vin is not allowed to be transmitted to the EM I filter 21, that is, the AC power source V i η is turned off. However, the present embodiment is not intended to limit the present invention. For example, the switch unit 251 can be modified to be coupled between the sigma filter 21 and the bridge rectifier 22. The voltage detector 26 is coupled between the two ends of the electrolytic capacitor 24 for detecting the voltage across the electrolytic capacitor 24 (ie, the DC voltage Vbus) to output a corresponding detection voltage Vsen. In this embodiment, the voltage detector 26 includes resistors R1 and R2, and the resistors R1 and R2 are coupled in series between the two ends of the electrolytic capacitor 24. The common terminal output of the resistors R1 and R2 and the electrolytic capacitor 24 The cross-voltage Vbus corresponding detection voltage Vsen, where Vsen = R2ARl + R2) x Vbus. [0014] The hysteresis comparator 27 is coupled between the voltage detector 26 and the driving circuit 28. The hysteresis comparator 27 generates a voltage across the voltage Vbus of the electrolytic capacitor 24 to be greater than the upper threshold value, that is, when the voltage across the voltage Vbus of the electrolytic capacitor 24 is abnormal but has not exceeded its maximum crossover voltage, Single Weave 1 Page 7 / Total 24 Page 1012022904-0 M435093 The drive circuit 28 drive control unit 252 controls the switch unit 251 to be turned off by conduction to immediately cut off the AC power supply Vin input. In addition, the hysteresis comparator 27 drives and controls the drive circuit 28 according to the detection voltage vsen when the voltage across the voltage of the electrolytic capacitor 24 drops to less than the lower threshold, that is, when the abnormality occurs in the voltage across the voltage Vbus* of the electrolytic capacitor 24. The unit 252 controls the switching unit 251 to become conductive from off to reconnect the AC power source Vin. The hysteresis comparator 27 determines the upper and lower thresholds of the voltage across the voltage Vbus of the electrolytic capacitor 24 to serve as a basis for the switching unit 251 of the relay 25 to be turned on or off, thereby suppressing noise interference and ensuring interference. The relay 25 does not malfunction or critically bounce. In one embodiment, the AC power supply Vin can be 90Vac to 264Vac, and the output of the PFC 23 can be designed to be about 400V. At this time, the upper and lower gates can be designed to be 570V and 380V, respectively. [0015] In the present embodiment, the hysteresis comparator 27 is an inverting hysteresis comparator including a transmissive amplifier OP1 and resistors R3 and R4, and the operational amplifier OP1 is powered by an internally generated stable DC voltage Vcc. . The hysteresis comparator 27 provides a high critical value Vth = R4 / (R3 + R4) x Vi * ef + R3 / (R3 + R4) x Vcc ' low threshold Vtl = R4 / (R3 + R4) x Vref - R3 / (R3 + R4) xVcc. When the detection voltage vsen rises above the high threshold value Vth, the hysteresis comparator 27 indicates that the voltage across the voltage Vbus of the electrolytic capacitor 24 rises to be greater than the upper threshold value Vth', so that the output control signal Vctl changes from the first level VI to the first level VI. The second level V0, the control signal Vet 1 having the second level v〇 is controlled by the drive circuit 28 to drive the control unit 252 to control the switch early element 2 51 to turn off from on. In addition, when the detection voltage Vsen falls below the low threshold value Vtl, the hysteresis comparator 27 represents the electrolytic capacitor, so the cross-voltage Vbus of the output 1012022904-0 24 falls below the lower limit threshold value vtl, 10120699# single number A01〇1 Page 8 of 24 M435093 The control signal Vctl is changed from the second level VO to the first level V1, and the control signal Vct1 having the first level VI is driven by the drive circuit 28 to control the switching unit 251. From disconnection to conduction. Wherein, the upper limit gate value Vth' = (Rl + R2) / R2xVth ' lower limit threshold value vtl, = (Rl + R2) / R2xVtl. [0016] Therefore, the high-low threshold values vth and Vtl provided by the hysteresis comparator 27 can be designed by adjusting the reference voltage Vref and the resistors R3 and R4, thereby formulating the detection of the cross-voltage Vbus of the electrolytic capacitor 24. The upper and lower thresholds are Vth' and Vtl'. The reference voltage Vref can be supplied by the reference voltage generator 29. The reference voltage generator 29 includes a shunt regulator U1, a resistor R5 and a capacitor C2. If the shunt regulator U1 ’ of the TL431 is used, the reference voltage is stable. 2. 5V «
圖3為圖2所示的驅動電路28及控制單元252的一實施 例的電路圖。請同時參見圖2及圖3，驅動電路38包括由 電阻器R6、PNP電晶體Q2及NPN電晶體Q3組成的圖騰柱電 路’其中，電阻器R6及電晶體Q2和Q3串聯耦接於内部直 流電壓Vcc及地之間’由電晶體Q2和Q3的基極端接收磁滞 比較器27輸出的控制信號Vctl，並由電晶體Q2和Q3的集 極端輸出驅動信號Vdr。控制單元352包括線圈Lry，線 圈Lry的一端耦接至驅動電路38以接收驅動信號Vdr且另 一端相接至地。 [〇〇18] 在本實施例中，第一準位VI及第二準位V0分別為高 準位及低準位。具有低準位（或第二準位V0)的控制信 1012022904-0 號Vctl會使驅動電路38中的圖騰柱電路的PNP電晶體Q2 10120699#單編號A〇1〇1 第9頁/共24頁 M435093 導通且NPN電晶體Q3截止以輸出具有高準位的驅動信號 Vdr，而具有高準位的驅動信號Vdr施加到控制單元352 中的線圈Lry上會產生電流流過線圈Lry而激磁以控制常 閉型的開關單元251斷開。具有高準位（或第一準位VI ) 的控制信號Vet 1會使驅動電路38中圖騰柱電路的PNP電 晶體Q2截止且NPN電晶體Q3導通以輸出具有低準位的驅動 信號Vdr，而具有低準位的驅動信號Vdr施加到控制單元 352中的線圈Lry上將無法產生電流流過線圈Lry，故線 圈Lry停止激磁以控制常閉型的開關單元251恢復導通。 [0019] 圖4為圖2所示的驅動電路28及控制單元252的另一實 施例的電路圖。請同時參見圖2及圖4，驅動電路48包括 第一單穩態多諧振盪器481及第二單穩態多諧振盪器482 。其中，第一單穩態多諧振盪器481包括由電容器C3及電 阻器R7組成的第一微分電路、用於限制單向導通的二極 體D6及由電晶體Q4和Q5、電容器C4、電阻器R8〜R11組 成的第一單穩態多諧振盪電路。第一單穩態多諧振盪器 481由第一微分電路接收控制信號Vet 1而在控制信號 Vet 1的波形上升緣時間點輸出正脈衝電壓及在波形下降 緣時間點輸出負脈衝電壓，並由第一單穩態多諧振盪電 路接收正、負脈衝電壓而在控制信號Vctl的波形下降緣 時間點產生正電壓的第一脈衝信號Vpl，故第一單穩態多 諧振盪器481接收控制信號Vctl並輸出具有第一脈衝信號 Vpl的驅動信號Vdrl。 [0020] 第二單穩態多諳振盪器482包括由電容器C5及電阻器 R12組成的第二微分電路、用於限制單向導通的二極體D7 10120699#單编號 A〇101 第10頁/共24頁 1012022904-0 M435093 及由電晶體Q6和Q7、電容器C6、電阻器R13〜R16組成的 第二單穩態多諧振皇電路。第二單穩態多證振盈器482由 第二微分電路接收控制信號Vctl而在控制信號“Η的波 形上升緣時間點輸出正脈衝電壓及在波形下降緣時間點 輸出負脈衝電壓，並由第二單穩態多諧振盪電路接收正 、負脈衝電壓而在控制信號Vet 1的波形上升緣時間點產 生正電壓的第二脈衝信號Vp2，故第二單穩態多諧振盪器 482接收控制信號Vctl並輸出具有第二脈衝信號Vp2的驅 動信號Vdr2。 ^ [0021] 控制單元452包括設定線圈Lst及重置線圈Lrst，設 定線圈Lst的一端耦接至第一單穩態多諧振盪器481以接 收驅動信號Vdrl且另一端耦接至地，而重置線圈Lrst的 一端耦接至第二單穩態多諧振盪器482以接收驅動信號 Vdr2且另一端耦接至地。 [0022] 在本實施例中，第一準位VI及第二準位V0分別為高 準位及低準位。由高準位變成低準位的轉換（或由第一 • 準位VI變成第二準位V0的轉換）會觸發第一單穩態多諧 振盪器481在控制信號Vet 1的波形下降緣時間點產生第一 脈衝信號Vpl ’而第一脈衝信號Vpl驅動設定線圈Lst控 制開關單元251由導通變成斷開。由低準位變成高準位的 轉換（或由第二準位V0變成第一準位VI的轉換）會觸發 第二單穩態多諧振盪器482在控制信號Vctl的波形上升緣 時間點產生第二脈衝信號Vp2，而第二脈衝信號Vp2驅動 重置線圈Lrst控制開關單元251由斷開變成導通° [0023] 因此，驅動電路48輸出的驅動信號vdrl和Vdr2實際 10120699产單編號 A01(n 第 11 頁 / 共 24 頁 1012022904-0 M435093 上即是在控制信號Vctl由高準位變成低準位的轉換時間 點（或波形下降緣時間點）產生第一脈·衝信號Vpl及在控 制信號Vctl由低準位變成高準位的轉換時間點（或波形 上升緣時間點）產生第二脈衝信號Vp2，其餘時間點上驅 動信號Vdrl和Vdr2均為低準位，因此可節能省電且線圈 Lst和Lrst較不會發熱。 [0024] 圖5為圖2所示的電源供應器2在輸入的交流電源Vin 電壓出現異常突波時執行過壓保護的波形示意圖。請同 時參見圖2及圖5，輸入的交流電源Vi η電壓在時間點t0後 數個週期（如4個）内出現異常突波，在電源供應器2正 常工作下，PFC 23的輸出電壓升高且致使其迴授電壓大 於迴授保護點時，PFC 23會自行關閉，此時電解電容器 24的跨壓Vbus將受到交流電源Vi η電壓峰值影響而開始 升高。在時間點tl時，偵測到電解電容器24的跨壓Vbus 上升至大於上限門檻值Vth，時，通過繼電器25的開關單 元251的斷開〇FF切斷交流電源Vin輸入。在切斷交流電 源Vin輸入期間，電源供應器2仍因電解電容器24上還具 備能量而繼續工作以提供直流電壓Vbus和Vcc，但其電壓 值會持續下降。 [0025] 在時間點t2時，偵測到電解電容器24的跨壓Vbus下 降至小於下限門檻值Vtl’ ，通過繼電器25的開關單元 251的導通ON重新接回交流電源Vin。但是，由於在時間 點t2時交流電源Vin電壓仍存在異常突波，故pfc 23仍 關閉’電解電容器24的跨壓Vbus又開始升高，並在時間 點13時上升至大於上限門檻值Vth，時而會切斷交流電源 1012〇699产單編號 A0101 第12頁/共24頁 1012022904-0 M435093 瞻 ·Fig. 3 is a circuit diagram showing an embodiment of the drive circuit 28 and the control unit 252 shown in Fig. 2. Referring to FIG. 2 and FIG. 3 simultaneously, the driving circuit 38 includes a totem pole circuit composed of a resistor R6, a PNP transistor Q2, and an NPN transistor Q3. The resistor R6 and the transistors Q2 and Q3 are coupled in series to the internal DC. The control signal Vctl output from the hysteresis comparator 27 is received by the base terminals of the transistors Q2 and Q3 between the voltage Vcc and the ground, and the drive signal Vdr is outputted from the collector terminals of the transistors Q2 and Q3. The control unit 352 includes a coil Lry, one end of which is coupled to the drive circuit 38 to receive the drive signal Vdr and the other end to ground. [18] In this embodiment, the first level VI and the second level V0 are respectively a high level and a low level. The control signal 1012022904-0 with the low level (or the second level V0) Vctl will make the PNP transistor of the totem pole circuit in the drive circuit 38 Q1 10120699# single number A〇1〇1 page 9/total 24 Page M435093 is turned on and the NPN transistor Q3 is turned off to output the driving signal Vdr having a high level, and the driving signal Vdr having the high level is applied to the coil Lry in the control unit 352 to generate a current flowing through the coil Lry to be excited to control The normally closed switching unit 251 is turned off. The control signal Vet 1 having a high level (or first level VI) causes the PNP transistor Q2 of the totem pole circuit in the driving circuit 38 to be turned off and the NPN transistor Q3 to be turned on to output the driving signal Vdr having a low level, and The driving signal Vdr having the low level applied to the coil Lry in the control unit 352 will not generate a current flowing through the coil Lry, so the coil Lry stops the excitation to control the normally closed type switching unit 251 to return to conduction. 4 is a circuit diagram of another embodiment of the drive circuit 28 and the control unit 252 shown in FIG. 2. Referring to FIG. 2 and FIG. 4 simultaneously, the driving circuit 48 includes a first monostable multivibrator 481 and a second monostable multivibrator 482. The first monostable multivibrator 481 includes a first differential circuit composed of a capacitor C3 and a resistor R7, a diode D6 for limiting the unidirectional conduction, and a transistor Q4 and Q5, a capacitor C4, and a resistor. The first monostable multi-resonant circuit composed of R8 RR11. The first monostable multivibrator 481 receives the control signal Vet 1 from the first differentiating circuit, outputs a positive pulse voltage at a time point of the rising edge of the waveform of the control signal Vet 1, and outputs a negative pulse voltage at a time point of the falling edge of the waveform, and is The first monostable multi-resonant circuit receives the positive and negative pulse voltages and generates a first pulse signal Vpl of a positive voltage at a time point of the falling edge of the waveform of the control signal Vctl, so the first monostable multivibrator 481 receives the control signal Vctl also outputs a drive signal Vdrl having a first pulse signal Vpl. [0020] The second monostable multi-turn oscillator 482 includes a second differential circuit composed of a capacitor C5 and a resistor R12, and a diode D7 for limiting the unidirectional conduction. 10120699#单号 A〇101第10页/ Total 24 pages 1012022904-0 M435093 and a second monostable multi-resonance circuit composed of transistors Q6 and Q7, capacitor C6, resistors R13~R16. The second monostable multi-symmetric vibrator 482 receives the control signal Vctl from the second differentiating circuit and outputs a positive pulse voltage at a time point of the rising edge of the control signal "Η" and outputs a negative pulse voltage at a time point of the falling edge of the waveform, and is The second monostable multi-resonant circuit receives the positive and negative pulse voltages and generates a second pulse signal Vp2 of a positive voltage at a rising edge of the waveform of the control signal Vet 1. Therefore, the second monostable multivibrator 482 receives the control. The signal Vct1 outputs a drive signal Vdr2 having the second pulse signal Vp2. [0021] The control unit 452 includes a set coil Lst and a reset coil Lrst, and one end of the set coil Lst is coupled to the first monostable multivibrator 481. The driving signal Vdrl is received and the other end is coupled to the ground, and one end of the reset coil Lrst is coupled to the second monostable multivibrator 482 to receive the driving signal Vdr2 and the other end is coupled to the ground. [0022] In this embodiment, the first level VI and the second level V0 are respectively a high level and a low level. The conversion from the high level to the low level (or from the first level to the second level) V0 conversion) will trigger the first The steady-state multivibrator 481 generates a first pulse signal Vpl' at a time point of the falling edge of the waveform of the control signal Vet1, and the first pulse signal Vpl drives the setting coil Lst to control the switching unit 251 to be turned off from on. The conversion of the high level (or the transition from the second level V0 to the first level VI) triggers the second monostable multivibrator 482 to generate the second pulse signal Vp2 at the rising edge of the control signal Vctl. And the second pulse signal Vp2 drives the reset coil Lrst to control the switch unit 251 to be turned on from the off state. [0023] Therefore, the drive signals vdrl and Vdr2 output by the drive circuit 48 are actually 10120699, the order number A01 (n page 11 / total On page 24, 1012022904-0 M435093, the first pulse-shooting signal Vpl is generated at the switching time point (or the waveform falling edge time point) at which the control signal Vctl changes from the high level to the low level, and the control signal Vctl is low-leveled. The switching time point (or the rising edge time point) of the high level generates the second pulse signal Vp2, and the driving signals Vdrl and Vdr2 are both low level at the remaining time points, thereby saving energy and coils Lst and Lrst are less likely to generate heat. [0024] FIG. 5 is a waveform diagram of the power supply 2 shown in FIG. 2 performing overvoltage protection when an abnormal surge occurs in the input AC power source voltage. Please refer to FIG. 2 and FIG. 5. The input AC power Vi η voltage has an abnormal surge within a few cycles (such as 4) after the time point t0. When the power supply 2 works normally, the output voltage of the PFC 23 rises and causes the feedback voltage to be When it is greater than the feedback protection point, the PFC 23 will turn off by itself, and the voltage across the voltage Vbus of the electrolytic capacitor 24 will be increased by the peak voltage of the AC power supply Vi η. At the time point t1, when it is detected that the voltage across the electrolytic capacitor 24 Vbus rises above the upper limit threshold value Vth, the AC power supply Vin input is cut off by the opening 〇FF of the switching unit 251 of the relay 25. During the interruption of the AC power source Vin input, the power supply 2 continues to operate due to the energy on the electrolytic capacitor 24 to provide the DC voltages Vbus and Vcc, but the voltage value continues to drop. [0025] At the time point t2, it is detected that the voltage across the voltage Vbus of the electrolytic capacitor 24 falls below the lower threshold value Vtl', and the AC power source Vin is reconnected by the ON of the switching unit 251 of the relay 25. However, since the AC power supply Vin voltage still has an abnormal surge at the time point t2, the pfc 23 is still turned off. The cross-voltage Vbus of the electrolytic capacitor 24 starts to rise again, and rises to a value greater than the upper limit threshold value Vth at the time point 13 . Sometimes it will cut off the AC power supply 1012〇699 Production order number A0101 Page 12 / Total 24 pages 1012022904-0 M435093
Vin輸入，及在時間點t4時下降至小於下限門檻值Vtl’ 而會接回交流電源V i η。最後，由於在時間點t4時交流電 源Vi η電壓已回復正常，故PFC 23開始正常工作，使電 解電容器24的跨壓Vbus回復正索。 [0026] 圖6為圖2所示的電源供應器2在PFC 23迴授異常時 執行過壓保護的波形示意圖。請同時參見圖2及圖6，輸 入的交流電源Vin電壓恆落於額定規範條件下，在時間點 t0時，PFC 23因迴授不良導致開關導通時間或責任週期 增大而造成其輸出電壓升高，使電解電容器24的跨壓 Vbus直接升高。在時間點11時，偵測到電解電容器24的 跨壓Vbus上升至大於上限門檻值Vth’時，通過繼電器 25的開關單元251的斷開OFF切斷交流電源Vin輸入。在 切斷交流電源Vin輸入期間，即使PFC 23的開關導通時 間或貴任週期再大，也會因為沒有輸入能量而無法工作 ，雖然PFC 23無法提供能量給電解電容器24，但電源供 應器2仍因電解電容器24上還具備能量而繼續工作以提供 ^ 直流電壓Vbus和Vcc，但其電壓值會持續下降。 • w [0027] 在時間點12時，偵測到電解電容器24的跨壓Vbus下 降至小於下限門檻值Vtl’ ，通過繼電器25的開關單元 251的導通ON重新接回交流電源Vin。但是，假設在時間 點t2時PFC 23仍存在迴授不良導致開關導通時間或責任 週期增大而造成其輸出電壓升高，使電解電容器24的跨 壓Vbus又開始升高，並在時間點t3時上升至大於上限門 檻值Vth’時而會切斷交流電源Vin輸入，及在時間點t4 時下降至小於下限門檻值Vt Γ而會接回交流電源Vin。 1〇12_^單編號 A0101 第13頁/共24頁 1012022904-0 M435093 最後，由於在時間點t4時PFC 23迴授已回復正常，故電 解電容器24的跨壓Vbus也會回復正常。 [0028] 綜上所述，本創作因採用直接偵測電解電容器的跨 壓，在偵測到電解電容器的跨壓發生異常但尚未超過其 最大跨壓時通過繼電器立即切斷交流電源輸入，並在異 常消失後通過繼電器重新接回交流電源，因此不論是輸 入的交流電源電壓出現異常突波或是PFC迴授異常產生的 電壓升高均不會影響到電解電容器，可防止電解電容器 爆炸或起火，以避免電解電容器在爆炸或起火時發生延 燒而產生危害。此外，在電解電容器的跨壓的偵測上制 訂出上、下限門檻值以作為繼電器切斷或接回交流電源 的依據，如此可抑制雜訊的干擾，確保繼電器不會誤動 作或臨界彈跳。 [0029] 雖然本創作已以較佳實施例揭露如上，然其並非用 於限定本創作，任何熟習此技藝者，在不脫離本創作之 精神和範圍内，當可作些許之更動與潤飾，因此本創作 之保護範圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 [0030] 圖1為一種現有的電源供應器的部分電路圖。 [0031] 圖2為根據本創作一實施例的電源供應器的部分電路 圖。 [0032] 圖3為圖2所示的驅動電路及控制單元的一實施例的 電路圖^ [0033] 圖4為圖2所示的驅動電路及控制單元的另一實施例 1()12()699f單編號A0101 第14頁/共24頁 1012022904-0 M435093 • * 的電路圖。 [0034] 圖5為圖2所示的電源供應器在輸入的交流電源電壓 出現異常突波時執行過壓保護的波形示意圖。 [0035] 圖6為圖2所示的電源供應器在PFC迴授異常時執行過The Vin input, and drops to less than the lower threshold value Vtl' at time t4, will return the AC power source V i η. Finally, since the AC power V η voltage has returned to normal at time t4, the PFC 23 starts normal operation, causing the voltage across the electrolytic capacitor 24 to return to the positive voltage. 6 is a waveform diagram of the power supply 2 shown in FIG. 2 performing overvoltage protection when the PFC 23 returns an abnormality. Please refer to FIG. 2 and FIG. 6 at the same time, the input AC power supply Vin voltage is constant under the rated specification condition. At the time point t0, the PFC 23 causes the switch on time or the duty cycle to increase due to the poor feedback, which causes the output voltage to rise. High, the voltage across the voltage Vbus of the electrolytic capacitor 24 is directly increased. At the time point 11, when it is detected that the voltage across the voltage Vbus of the electrolytic capacitor 24 rises above the upper limit threshold value Vth', the AC power supply Vin input is cut off by the OFF of the switching unit 251 of the relay 25. During the interruption of the AC power supply Vin input, even if the switch on time or the noble period of the PFC 23 is large, it will not work because there is no input energy. Although the PFC 23 cannot supply energy to the electrolytic capacitor 24, the power supply 2 remains Since the electrolytic capacitor 24 still has energy, it continues to operate to provide the DC voltages Vbus and Vcc, but the voltage value thereof continues to drop. • w [0027] At time 12, the voltage across the voltage Vbus of the electrolytic capacitor 24 is detected to fall below the lower threshold value Vtl', and the AC power source Vin is reconnected by the ON of the switching unit 251 of the relay 25. However, it is assumed that there is still a poor feedback in the PFC 23 at the time point t2, causing the switch on time or the duty cycle to increase, causing its output voltage to rise, causing the voltage across the electrolytic capacitor 24 to rise again, at time t3. When the temperature rises above the upper threshold value Vth', the AC power supply Vin input is cut off, and when the time point t4 falls below the lower threshold value Vt Γ, the AC power supply Vin is connected. 1〇12_^单号 A0101 Page 13 of 24 1012022904-0 M435093 Finally, since the PFC 23 feedback has returned to normal at time t4, the crossover voltage Vbus of the electrolytic capacitor 24 will return to normal. [0028] In summary, the present invention uses a direct detection of the cross-voltage of the electrolytic capacitor, and immediately detects that the cross-voltage of the electrolytic capacitor is abnormal but has not exceeded its maximum cross-voltage, and immediately cuts off the AC power input through the relay, and After the abnormal disappearance, the AC power is reconnected through the relay. Therefore, the abnormal voltage generated by the input AC power supply voltage or the voltage rise caused by the PFC feedback abnormality will not affect the electrolytic capacitor, preventing the electrolytic capacitor from exploding or igniting. In order to avoid the occurrence of damage caused by the burning of the electrolytic capacitor in the event of an explosion or fire. In addition, the upper and lower thresholds are determined on the detection of the cross-voltage of the electrolytic capacitor as the basis for the relay to cut off or connect back to the AC power supply, so as to suppress the interference of the noise and ensure that the relay does not malfunction or critically bounce. [0029] While the present invention has been described above by way of a preferred embodiment, it is not intended to limit the present invention, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this creation is subject to the definition of the scope of the patent application attached. BRIEF DESCRIPTION OF THE DRAWINGS [0030] FIG. 1 is a partial circuit diagram of a conventional power supply. 2 is a partial circuit diagram of a power supply according to an embodiment of the present invention. 3 is a circuit diagram of an embodiment of the driving circuit and the control unit shown in FIG. 2. [0033] FIG. 4 is another embodiment 1()12() of the driving circuit and the control unit shown in FIG. 699f single number A0101 page 14 / total 24 pages 1012022904-0 M435093 • * circuit diagram. 5 is a waveform diagram of the power supply shown in FIG. 2 performing overvoltage protection when an abnormal surge occurs in the input AC power supply voltage. [0035] FIG. 6 is a diagram of the power supply shown in FIG. 2 executed when a PFC feedback exception occurs.
壓保護的波形示意圖。 【主要元件符號說明】 [0036] 1、2 :電源供應器 10、20 :交流電源線 [0037] 11、21 : EMI濾波器 12、22 :橋式整流器 [0038] 13、23 : PFC 14、24 :電解電容器 [0039] 25 :繼電器 251 :開關單元 [0040] 252、352、452 :控制單元 2 6 :電壓偵測器 [0041] 27 :磁滯比較器 28、38、48 :驅動電路 [0042] 29 :參考電壓產生器 481 :第一單穩態多諧振盪器 [0043] 482 :第二單穩態多諧振盪器 C1〜C6 :電容器 [0044] D1〜D7 :二極體 LI、L2 :電感器 [0045] L r y :線圈 Lst :設定線圈 [0046] Lrst :重置線圈 OP1 :運算放大器 [0047] Q1〜Q7 :電晶體 R1〜R16 :電阻器 [0048] U1 :並聯穩壓器 V i η :交流電源 [0049] Vbus、Vcc :直流電壓 Vsen :偵測電壓 1012069#^ A0101 第15頁/共24頁 1012022904-0 M435093 [0050] Vref :參考電壓 Vet 1 :控制信號 [0051] VI :第一準位 V0 :第二準位 [0052] Vdr、Vdrl、Vdr2 :驅動信號 Vpl :第一脈衝信號 [0053] Vp2 :第二脈衝信號 Vth’ ：上限門檻值 [0054] Vtl’ ：下限門檻值 ON :開關單元導通 [0055] OFF :開關單元斷開 t :時間 [0056] ΐ0〜t4 :時間點Waveform diagram of voltage protection. [Main component symbol description] [0036] 1, 2: power supply 10, 20: AC power supply line [0037] 11, 21: EMI filter 12, 22: bridge rectifier [0038] 13, 23: PFC 14, 24: Electrolytic capacitor [0039] 25: Relay 251: Switch unit [0040] 252, 352, 452: Control unit 2 6 : Voltage detector [0041] 27: Hysteresis comparator 28, 38, 48: Drive circuit [ 0042] 29: reference voltage generator 481: first monostable multivibrator [0043] 482: second monostable multivibrator C1 to C6: capacitor [0044] D1 to D7: diode LI, L2 : Inductor [0045] L ry : Coil Lst : Set coil [0046] Lrst : Reset coil OP1 : Operational amplifier [0047] Q1 to Q7 : Transistor R1 to R16 : Resistor [0048] U1 : Shunt regulator V i η : AC power supply [0049] Vbus, Vcc : DC voltage Vsen : Detection voltage 1012069 #^ A0101 Page 15 / Total 24 pages 1012022904-0 M435093 [0050] Vref : Reference voltage Vet 1 : Control signal [0051 VI: first level V0: second level [0052] Vdr, Vdrl, Vdr2: drive signal Vpl: first pulse signal [0053] Vp2: second pulse signal Vth' : upper limit threshold [0054] Vtl' : lower threshold value ON : switch unit is turned on [0055] OFF : switch unit is off t : time [0056] ΐ0~t4 : time point
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