Totem-pole power factor correction circuit

Abstract

The detection module of the totem pole power factor correction circuit in this case includes a detection resistor and a detection circuit. When the control unit confirms that the output voltage of the detection circuit is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, the control unit controls at least the third and fourth switching elements to be turned off. Therefore, the totem pole power factor correction circuit can quickly control the corresponding switching elements to be turned off based on whether the output voltage of the detection circuit is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold. This means that the totem pole power factor correction circuit can take protective measures in time to avoid damage to the totem pole power factor correction circuit. Therefore, the totem pole power factor correction circuit has the advantage of better performance.

Description

Technical Field

[0001] This case relates to a totem pole power factor correction circuit, and more particularly to a totem pole power factor correction circuit that includes a detection module. Background Technology

[0002] Traditional power factor correction (PFC) circuits suffer from high efficiency due to the large number of switching elements and high reverse recovery losses. In contrast, totem-pole PFC circuits have fewer switching elements, resulting in higher efficiency. Furthermore, because totem-pole PFC circuits are mostly constructed from wide-bandgap semiconductor materials, they exhibit lower reverse recovery losses, leading to their widespread use.

[0003] Totem-pole power factor correction circuits typically include a bypass diode. During normal operation, the bypass diode is off, allowing the input current to flow evenly through the other switching elements within the circuit, thus protecting it. However, during abnormal operation—for example, if a switching element is erroneously triggered or the input voltage suddenly reverses due to lightning or other unforeseen events, causing a delay in control response—the input current connected to the bypass diode becomes short-circuited. This means the current flows only through a single switching element, potentially leading to excessive current flow and ultimately damaging the circuit.

[0004] Therefore, how to develop a totem pole power factor correction circuit to solve the problems faced by existing technologies is an urgent issue that needs to be addressed in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a totem pole power factor correction circuit that has the advantage of better performance.

[0006] To achieve the above objectives, a preferred embodiment of this invention provides a totem-pole power factor correction circuit electrically coupled between an input power supply and a load. The input power supply has a first terminal and a second terminal. The totem-pole power factor correction circuit includes a first bridge arm, a second bridge arm, a third bridge arm, a first inductor, a detection module, and a control unit. The first bridge arm includes a first bypass diode and a second bypass diode connected in series, with the connection point between the first and second bypass diodes forming a first connection point. The second bridge arm is connected in parallel with the first bridge arm and includes a first switching element and a second switching element connected in series, with the connection point between the first and second switching elements forming a second connection point. The third bridge arm is connected in parallel with the first bridge arm and includes a third switching element and a fourth switching element connected in series, with the connection point between the third and fourth switching elements forming a third connection point, which is electrically connected to the second terminal of the input power supply. The first inductor is electrically connected between the first terminal of the input power supply and the second connection point. The detection module includes a detection resistor and a detection circuit. The detection resistor includes a first terminal and a second terminal, and the detection circuit includes a first terminal, a second terminal, and a third terminal. The first terminal of the sensing resistor, the first connection point, and the first terminal of the sensing circuit are all connected together. The second terminal of the sensing resistor, the first terminal of the input power supply, and the second terminal of the sensing circuit are all connected together. The control unit is electrically coupled to the third terminal of the sensing circuit to control the first, second, third, and fourth switching elements. The sensing circuit detects the voltage difference across the sensing resistor and outputs an output voltage from the third terminal of the sensing circuit. When the control unit confirms that the output voltage of the sensing circuit is greater than or equal to the upper voltage threshold, or less than or equal to the lower voltage threshold, the control unit controls at least the third and fourth switching elements to turn off.

[0007] To achieve the above objectives, another preferred embodiment of this invention provides a totem-pole power factor correction circuit electrically coupled between an input power supply and a load. The input power supply has a first terminal and a second terminal. The totem-pole power factor correction circuit includes a first bridge arm, a second bridge arm, a third bridge arm, a first inductor, a detection module, and a control unit. The first bridge arm includes a first bypass diode and a second bypass diode connected in series. The connection point between the first bypass diode and the second bypass diode forms a first connection point, which is electrically connected to the first terminal of the input power supply. The second bridge arm is connected in parallel with the first bridge arm and includes a first switching element and a second switching element connected in series. The connection point between the first switching element and the second switching element forms a second connection point. The third bridge arm is connected in parallel with the first bridge arm and includes a third switching element and a fourth switching element connected in series. The connection point between the third switching element and the fourth switching element forms a third connection point. The first inductor is electrically connected between the first terminal of the input power supply and the second connection point. The sensing resistor includes a first terminal and a second terminal, and the sensing circuit includes a first terminal, a second terminal, and a third terminal. The first terminal of the sensing resistor, the second terminal of the input power supply, and the first terminal of the sensing circuit are connected together. The second terminal of the sensing resistor, the third connection point, and the second terminal of the sensing circuit are also connected together. The control unit is electrically coupled to the third terminal of the sensing circuit to control the first, second, third, and fourth switching elements. The sensing circuit detects the voltage difference across the sensing resistor and outputs an output voltage from its third terminal. When the control unit confirms that the output voltage of the sensing circuit is greater than or equal to the upper voltage threshold, or less than or equal to the lower voltage threshold, the control unit controls at least the third and fourth switching elements to turn off. Attached Figure Description

[0008] Figure 1 This is a circuit topology diagram of the totem pole power factor correction circuit in the first embodiment of this case.

[0009] Figure 2A and Figure 2B for Figure 1 The diagram shows the current flow topology of the totem pole power factor correction circuit when the input power supply voltage is in the positive half-cycle.

[0010] Figure 3A and Figure 3B for Figure 1 The diagram shows the current flow topology of the totem pole power factor correction circuit when the input power supply voltage is in the negative half-cycle.

[0011] Figure 4 This is a circuit topology diagram of the totem pole power factor correction circuit in the second embodiment of this case.

[0012] Figure 5This is a circuit topology diagram of the totem pole power factor correction circuit in the third embodiment of this case.

[0013] Figure 6 This is a circuit topology diagram of the totem pole power factor correction circuit in the fourth embodiment of this case.

[0014] Figure 7 This is a circuit topology diagram of the totem pole power factor correction circuit in the fifth embodiment of this case.

[0015] Figure 8 This is a circuit topology diagram of the totem pole power factor correction circuit in the sixth embodiment of this case.

[0016] Figure 9 This is a circuit topology diagram of the totem pole power factor correction circuit in the seventh embodiment of this case.

[0017] Figure 10 This is a circuit topology diagram of the totem pole power factor correction circuit in the eighth embodiment of this case.

[0018] Figure 11 This is a circuit topology diagram of the totem pole power factor correction circuit in the ninth embodiment of this case.

[0019] Figure 12 This is a circuit topology diagram of the totem pole power factor correction circuit in the tenth embodiment of this case.

[0020] Figure 13 This is a circuit topology diagram of the totem pole power factor correction circuit of the eleventh embodiment of this case.

[0021] The reference numerals in the attached figures are explained as follows:

[0022] 1, 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j: Totem Pole Power Factor Correction Circuit

[0023] Vac: Input power

[0024] 11: First end

[0025] 12: Second end

[0026] Vo+: Positive output terminal

[0027] Vo-: Negative output terminal

[0028] 2: First bridge arm

[0029] D1: First bypass diode

[0030] D2: Second bypass diode

[0031] A: First connection point

[0032] 3: Second bridge arm

[0033] S1: First switching element

[0034] S2: Second switching element

[0035] B: Second connection point

[0036] 4: Third bridge arm

[0037] S3: Third switching element

[0038] S4: Fourth switching element

[0039] C: Third connection point

[0040] 5: Fourth bridge arm

[0041] S5: Fifth switching element

[0042] S6: Sixth switching element

[0043] D: Fourth connection point

[0044] 6: Detection Module

[0045] Res: Sensing resistor

[0046] 601: First end

[0047] 602: Second end

[0048] 61: Detection Circuit

[0049] 611: First end

[0050] 612: Second end

[0051] 613: Third end

[0052] M: Amplifier

[0053] R1: First resistor

[0054] R2: Second resistor

[0055] R3: Third resistor

[0056] DC_bias: DC power supply

[0057] Rf: Filter resistor

[0058] Cf: Filter capacitor

[0059] R4: First voltage divider resistor

[0060] R5: Second voltage divider resistor

[0061] 7: Control Unit

[0062] L1: First Inductor

[0063] L2: Second Inductor

[0064] Co: Output capacitor

[0065] 8: Fifth bridge arm

[0066] D3: Third bypass diode

[0067] D4: Fourth bypass diode

[0068] E: Fifth connection point

[0069] ZD: Zener diode Detailed Implementation

[0070] Some typical embodiments that embody the features and advantages of this invention will be described in detail in the following description. It should be understood that this invention can have various variations in different forms, all of which do not depart from the scope of this invention, and the descriptions and drawings therein are for illustrative purposes only and not for limiting this invention.

[0071] Please see Figure 1 This is the circuit topology diagram of the totem pole power factor correction circuit in the first embodiment of this case. Figure 1As shown, the totem-pole power factor correction circuit 1 of this invention receives AC input power from the input power source Vac and converts it into output power to a load (not shown). The input power source Vac has a first terminal 11 and a second terminal 12. When the input power source Vac is in the positive half-cycle of AC power, the voltage at the first terminal 11 of the input power source Vac is higher than the voltage at the second terminal 12. The current of the input power source Vac flows out from the first terminal 11, making the first terminal 11 the positive input terminal of the totem-pole power factor correction circuit 1. The current of the totem-pole power factor correction circuit 1 flows into the input power source Vac through the second terminal 12, making the second terminal 12 the negative input terminal of the totem-pole power factor correction circuit 1. When the input power supply Vac is in the negative half-cycle of AC, the voltage at the first terminal 11 of the input power supply Vac is lower than the voltage at the second terminal 12. Current from the input power supply Vac flows out from the second terminal 12, making the second terminal 12 the positive input terminal of the totem-pole power factor correction circuit 1. Meanwhile, current from the totem-pole power factor correction circuit 1 flows into the input power supply Vac through the first terminal 11, making the first terminal 11 the negative input terminal of the totem-pole power factor correction circuit 1. The totem-pole power factor correction circuit 1 includes a positive output terminal Vo+, a negative output terminal Vo-, a first bridge arm 2, a second bridge arm 3, a third bridge arm 4, a detection module 6, a control unit 7, and a first inductor L1. The totem-pole power factor correction circuit 1 transmits the converted output energy to the load via the positive output terminal Vo+ and the negative output terminal Vo-. The totem-pole power factor correction circuit 1 is electrically coupled to the load; that is, the load can be directly connected to the totem-pole power factor correction circuit 1 or indirectly connected to it.

[0072] The first bridge arm 2 includes a first bypass diode D1 and a second bypass diode D2 connected in series. The cathode of the first bypass diode D1 and the anode of the second bypass diode D2 are electrically connected to the positive output terminal Vo+ and the negative output terminal Vo-, respectively. The anode of the first bypass diode D1 and the cathode of the second bypass diode D2 are electrically connected to form a first connection point A. The first connection point A is electrically connected to the detection module 6.

[0073] The second bridge arm 3 is connected in parallel with the first bridge arm 2 and includes a first switching element S1 and a second switching element S2. The first switching element S1 and the second switching element S2 are connected in series between the output positive terminal Vo+ and the output negative terminal Vo-, and the connection point between the first switching element S1 and the second switching element S2 forms a second connection point B. The first switching element S1 and the second switching element S2 are electrically connected to the control unit 7 through a drive module (not shown), and the control unit 7 controls the conduction or deactivation of the first switching element S1 and the second switching element S2. In this embodiment, the first switching element S1 and the second switching element S2 can be gallium nitride (GaN), silicon carbide (SiC), or metal oxide semiconductor field-effect transistor (MOSFET), respectively. The first inductor L1 is electrically connected between the first terminal 11 of the input power supply Vac and the second connection point B.

[0074] The third bridge arm 4 is connected in parallel with the first bridge arm 2 and the second bridge arm 3, and includes a third switching element S3 and a fourth switching element S4. The third switching element S3 and the fourth switching element S4 are connected in series between the output positive terminal Vo+ and the output negative terminal Vo-, and the connection point between the third switching element S3 and the fourth switching element S4 forms a third connection point C. The third connection point C is electrically connected to the second terminal 12 of the input power supply Vac. The third switching element S3 and the fourth switching element S4 are electrically connected to the control unit 7 through a drive module (not shown), and the control unit 7 controls the conduction or deactivation of the third switching element S3 and the fourth switching element S4. In this embodiment, the third switching element S3 and the fourth switching element S4 can be gallium nitride (GaN), silicon carbide (SiC), or metal oxide semiconductor field-effect transistor (MOSFET), respectively. In some embodiments, the totem pole power factor correction circuit 1 may also include an output capacitor Co, which is electrically connected between the output positive terminal Vo+ and the output negative terminal Vo-.

[0075] To further illustrate the current flow direction of the totem pole power factor correction circuit 1, please refer to [link / reference needed]. Figure 2A , Figure 2B , Figure 3A and Figure 3B ,in Figure 2A and Figure 2B for Figure 1 The diagram shows the current flow topology of the totem pole power factor correction circuit when the input power supply voltage is in the positive half-cycle. Figure 3A and Figure 3B for Figure 1 The diagram shows the current flow topology of the totem pole power factor correction circuit when the input power supply voltage is in the negative half-cycle. To facilitate explanation of the current flow in totem pole power factor correction circuit 1, the diagram is shown below. Figure 2A , Figure 2B , Figure 3A and Figure 3B In the diagram, detection module 6 is not shown.

[0076] When the input power supply Vac provides the power supply voltage during the positive half-cycle of the AC voltage, and the first inductor L1 is in the energy storage stage, such as Figure 2A As shown, control unit 7 controls the second switching element S2 and the fourth switching element S4 to be turned on, and controls the first switching element S1 and the third switching element S3 to be turned off. The current supplied by the input power supply Vac flows out from the first terminal 11 and sequentially flows to the first inductor L1, the second switching element S2, the fourth switching element S4, and the second terminal 12 of the input power supply Vac to charge the first inductor L1. When the first inductor L1 completes charging and enters the discharging phase, as... Figure 2B As shown, the control unit 7 controls the first switching element S1 and the fourth switching element S4 to be turned on, and controls the second switching element S2 and the third switching element S3 to be turned off. The current provided by the input power supply Vac flows out from the first terminal 11 and flows sequentially to the first inductor L1, the first switching element S1, the output capacitor Co (and / or the load), the fourth switching element S4 and the second terminal 12 of the input power supply Vac, so as to charge the output capacitor Co (and / or supply power to the load).

[0077] When the input power supply Vac provides the power supply voltage during the negative half-cycle of the AC voltage, and the first inductor L1 is in the energy storage stage, such as Figure 3A As shown, control unit 7 controls the first switching element S1 and the third switching element S3 to be turned on, and controls the second switching element S2 and the fourth switching element S4 to be turned off. The current supplied by the input power supply Vac flows out from the second terminal 12 and sequentially flows to the third switching element S3, the first switching element S1, the first inductor L1, and the first terminal 11 of the input power supply Vac to charge the first inductor L1. When the first inductor L1 completes charging and enters the discharging phase, as... Figure 3B As shown, the control unit 7 controls the second switching element S2 and the third switching element S3 to be turned on, and controls the first switching element S1 and the fourth switching element S4 to be turned off. The current provided by the input power supply Vac flows out from the second terminal 12 and flows sequentially to the third switching element S3, the output capacitor Co (and / or the load), the second switching element S2, the first inductor L1 and the first terminal 11 of the input power supply Vac, so as to charge the output capacitor Co (and / or supply power to the load).

[0078] Please refer to the previous document. Figure 1The detection module 6 includes a detection resistor Res and a detection circuit 61. The detection resistor Res includes a first terminal 601 and a second terminal 602. The first terminal 601 of the detection circuit Res is electrically connected to the anode of the first bypass diode D1, and the second terminal 602 of the detection circuit Res is electrically connected to the first terminal 11 of the input power supply Vac. The current provided by the input power supply Vac can flow through the detection resistor Res. The detection circuit 61 includes a first terminal 611, a second terminal 612, and a third terminal 613. The first terminal 611 of the detection circuit 61, the first terminal 601 of the detection circuit Res, and the first connection point A are connected together. The second terminal 612 of the detection circuit 61, the second terminal 602 of the detection resistor Res, and the first terminal 11 of the input power supply Vac are connected together. The third terminal 613 of the detection circuit 61 is electrically connected to the control unit 7. When the current provided by the input power supply Vac flows through the detection resistor Res, the voltage difference across the detection resistor Res is detected by the first terminal 611 and the second terminal 612 of the detection circuit 61. The detection circuit 61 further outputs an output voltage based on the voltage difference across the detection resistor Res and transmits the output voltage to the control unit 7 through the third terminal 613 of the detection circuit 61. This means that the detection circuit 61 detects the voltage difference across the detection resistor Res and outputs the output voltage from the third terminal 613 of the detection circuit 61. The control unit 7 is electrically connected to the third terminal 613 of the detection circuit 61 to control all switching elements (i.e., the first switching element S1, the second switching element S2, the third switching element S3 and the fourth switching element S4). The control unit 7 controls the corresponding switching element to be turned on or off according to whether the output voltage from the third terminal of the detection circuit 61 is between the upper voltage threshold and the lower voltage threshold. One output terminal of the control unit 7 is grounded.

[0079] For example, when the input power supply Vac provides the power supply voltage during the positive half-cycle of the AC voltage, and the first inductor L1 is in the energy storage stage, such as Figure 2A As shown, when the control unit 7 further confirms that the output voltage of the detection circuit 61 is between the lower voltage threshold and the upper voltage threshold, the control unit 7 controls the second switching element S2 and the fourth switching element S4 to be turned on, and the first switching element S1 and the third switching element S3 to be turned off; and when the power supply voltage provided by the input power supply Vac is the positive half-cycle of the AC voltage, and the first inductor L1 is in the discharge stage, as Figure 2B As shown, when the control unit 7 further confirms that the output voltage of the detection circuit 61 is between the lower voltage threshold and the upper voltage threshold, the control unit 7 controls the first switching element S1 and the fourth switching element S4 to be turned on, and the second switching element S2 and the third switching element S3 to be turned off; and when the power supply voltage provided by the input power supply Vac is the negative half-cycle of the AC voltage, and the first inductor L1 is in the energy storage stage, as Figure 3AAs shown, when the control unit 7 further confirms that the output voltage of the detection circuit 61 is between the lower voltage threshold and the upper voltage threshold, the control unit 7 controls the first switching element S1 and the third switching element S3 to be turned on, and the second switching element S2 and the fourth switching element S4 to be turned off; and when the power supply voltage provided by the input power supply Vac is the negative half-cycle of the AC voltage, and the first inductor L1 is in the discharge stage, as Figure 3B As shown, when the control unit 7 further confirms that the output voltage of the detection circuit 61 is between the lower voltage threshold and the upper voltage threshold, the control unit 7 controls the second switching element S2 and the third switching element S3 to be turned on, and the first switching element S1 and the fourth switching element S4 to be turned off. When the control unit 7 confirms that the output voltage of the detection circuit 61 is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, the control unit 7 controls at least the third switching element S3 and the fourth switching element S4 to be turned off. In one embodiment, when the control unit 7 confirms that the output voltage of the detection circuit 61 is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, the control unit 7 controls the first switching element S1, the second switching element S2, the third switching element S3, and the fourth switching element S4 to all be turned off.

[0080] As can be seen from the above, the detection module 6 of the totem pole power factor correction circuit 1 in this case includes a detection resistor Res and a detection circuit 61. When the control unit 7 confirms that the output voltage of the detection circuit 61 is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, the control unit 7 controls at least the third switching element S3 and the fourth switching element S4 to turn off. That is, by comparing the output voltage of the detection circuit 61 with an upper voltage threshold and a lower voltage threshold, it is determined whether the totem pole power factor correction circuit 1 is working normally. When the output voltage of the detection circuit 61 is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, it can be determined that the totem pole power factor correction circuit 1 is working abnormally (e.g., short circuit), and the control unit 7 controls the corresponding switching element to turn off to protect the totem pole power factor correction circuit 1. Therefore, when the voltage of the input power supply suddenly reverses due to sudden events such as lightning, and the control fails to keep up due to delay, or when the switching element is erroneously triggered (e.g., short circuit), the totem pole power factor correction circuit 1 is protected. Figure 2A In the middle, the switch element S4 should be turned on, but the switch element S3 should be turned on instead; Figure 3AIn the case of a short circuit in the input power supply caused by controlling switch element S4 to be turned on instead of switch element S3, the totem pole power factor correction circuit 1 of this invention can quickly control the corresponding switch element to turn off by detecting whether the output voltage of the detection circuit 61 is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold. This means that the totem pole power factor correction circuit 1 of this invention can take protective measures in time to avoid damage to the totem pole power factor correction circuit 1. Therefore, the totem pole power factor correction circuit 1 of this invention has the advantage of better performance.

[0081] In some embodiments, the detection circuit 61 of the detection module 6 may be composed of an inverse proportional amplifier circuit; please refer to [link to relevant documentation]. Figure 4 This is a circuit topology diagram of the totem pole power factor correction circuit in the second embodiment of this case. Figure 4 As shown, the detection circuit 61 of the totem pole power factor correction circuit 1a in this embodiment includes an amplifier M, a first resistor R1, a second resistor R2, a third resistor R3, and a DC power supply DC_bias. The output terminal of the amplifier M is electrically connected to the third terminal 613 of the detection circuit 61. The first resistor R1 is electrically connected between the negative input terminal of the amplifier M and the first terminal 611 of the detection circuit 61. The second resistor R2 is electrically connected between the positive input terminal of the amplifier M and the second terminal 612 of the detection circuit 61. The third resistor R3 is electrically connected between the negative input terminal and the output terminal of the amplifier M. The positive terminal of the DC power supply DC_bias is electrically coupled to the positive input terminal of the amplifier M, and the negative terminal of the DC power supply DC_bias is electrically connected to the second terminal 612 of the detection circuit 61 and grounded. The DC power supply DC_bias is used to provide a positive bias voltage to the amplifier M. In some embodiments, the DC power supply DC_bias may be, but is not limited to, the output voltage of a linear regulator circuit, the output voltage of a Buck converter circuit, or the output voltage of a Flyback converter circuit.

[0082] When the input power supply Vac is in the positive half-cycle of the AC voltage, the current supplied by the input power supply Vac flows from the first terminal 11 of the input power supply Vac through the sensing resistor Res and then to the first terminal 611 of the detection circuit 61. In this case, a voltage drop occurs across the sensing resistor Res, and the voltage difference across the sensing resistor Res is Iinrush * Res, where Iinrush is the current flowing through the sensing resistor Res and Res is the resistance value of the sensing resistor. After the voltage difference across the sensing resistor Res is differentially processed by the amplifier M, the amplifier M outputs an output voltage to the control unit 7. That is, the voltage difference across the sensing resistor Res is amplified and biased by the detection circuit, and then an output voltage is output to the control unit 7. The output voltage output by the amplifier M is... Where DC_bias is the DC voltage provided by the DC power supply, R1 is the resistance value of the first resistor, and R3 is the resistance value of the third resistor. The control unit 7 further controls the corresponding switching element to turn on or off based on whether the output voltage of the detection circuit 61 is between an upper voltage threshold and a lower voltage threshold. For example, when the control unit 7 confirms that the output voltage of the detection circuit 61 is greater than or equal to an upper voltage threshold, or less than or equal to a lower voltage threshold, the control unit 7 determines that the totem pole power factor correction circuit 1 is in an abnormal operating state (e.g., short circuit), and then the control unit 7 controls the corresponding switching element to turn off to protect the totem pole power factor correction circuit 1. In some embodiments, the upper voltage threshold may be, for example, [missing information].

[0083] When the input power supply Vac is in the negative half-cycle of the AC voltage, the current supplied by the input power supply Vac flows from the first terminal 611 of the detection circuit 61 through the detection resistor Res and the second terminal 612 of the detection circuit 61, and then into the first terminal 11 of the input power supply Vac. In this case, a voltage drop occurs across the detection resistor Res, and the voltage difference across the detection resistor Res is -Iinrush*Res. After the voltage difference across the detection resistor Res is differentially processed by the amplifier M, the amplifier M outputs an output voltage to the control unit 7. That is, the voltage difference across the detection resistor Res is amplified and biased by the detection circuit to output an output voltage to the control unit 7, where the output voltage output by the amplifier M is... The control unit 7 further controls the corresponding switching element to turn on or off based on whether the output voltage of the detection circuit 61 is between the upper voltage threshold and the lower voltage threshold. For example, when the control unit 7 confirms that the output voltage of the detection circuit 61 is greater than or equal to an upper voltage threshold, or less than or equal to a lower voltage threshold, the control unit 7 determines that the totem pole power factor correction circuit 1 is in an abnormal operating state (e.g., short circuit). The control unit 7 then controls the corresponding switching element to turn off to protect the totem pole power factor correction circuit 1. In some embodiments, the lower voltage threshold may be, for example, [missing information].

[0084] In some embodiments, the number of switching elements in the totem pole power factor correction circuit can be adjusted according to actual needs, and is not limited to, for example... Figure 1 The four switching elements are shown. Please refer to [link / reference]. Figure 5 This is the circuit topology diagram of the totem pole power factor correction circuit in the third embodiment of this case. Compared to Figure 1The totem pole power factor correction circuit 1 shown contains only four switching elements (i.e., the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4). The totem pole power factor correction circuit 1b of this embodiment contains six switching elements, that is, in addition to the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4, it also includes a fifth switching element S5 and a sixth switching element S6. The fifth switching element S5 and the sixth switching element S6 are connected in series to the positive output terminal Vo+ and the negative output terminal Vo-. The fourth bridge arm 5 is formed by connecting the first bridge arm 2, the second bridge arm 3, and the third bridge arm 4 in parallel. The connection point between the fifth switching element S5 and the sixth switching element S6 forms the fourth connection point D. The fifth switching element S5 and the sixth switching element S6 are electrically connected to the control unit 7 through a drive module (not shown). The control unit 7 then controls the conduction or deactivation of the fifth switching element S5 and the sixth switching element S6. The operation mode of the fifth switching element S5 and the sixth switching element S6 in the fourth bridge arm 5 is similar to that of the first switching element S1 and the second switching element S2 in the second bridge arm 3, so it will not be described again here. In this embodiment, the fifth switching element S5 and the sixth switching element S6 can be gallium nitride (GaN), silicon carbide (SiC), or metal oxide semiconductor field-effect transistor (MOSFET), respectively. The totem pole power factor correction circuit 1b of this embodiment further includes a second inductor L2, which is electrically connected between the first terminal 11 of the input power supply Vac and the fourth connection point D.

[0085] To prevent interference with the output voltage of the detection circuit 61, which could cause incorrect judgment by the control unit 7, in some embodiments, the detection circuit 61 also includes a filter resistor and a filter capacitor. Please refer to [link to relevant documentation]. Figure 6 This is the circuit topology diagram of the totem pole power factor correction circuit in the fourth embodiment of this case. Compared to Figure 4 The totem pole power factor correction circuit 1a shown in this embodiment, and the detection circuit 61 of the totem pole power factor correction circuit 1c in this embodiment, further include a filter resistor Rf and a filter capacitor Cf. The filter resistor Rf is electrically connected between the output terminal of the amplifier M and the third terminal 613 of the detection circuit 61, and the filter capacitor Cf is electrically connected between the filter resistor Rf and the second terminal 612 of the detection circuit 61. The filter resistor Rf and the filter capacitor Cf cooperate with each other to filter the output voltage. Further, in some embodiments, the detection circuit 61 may also include a Zener diode ZD, such as... Figure 6As shown, the anode of the Zener diode ZD is connected to the second terminal 612 of the detection circuit 61, and the cathode of the Zener diode ZD is connected to the third terminal 613 of the detection circuit 61. The Zener diode ZD can be used to clamp and protect the output voltage transmitted from the detection circuit 61 to the control unit 7.

[0086] In this embodiment, to increase the flexibility of the DC power supply DC_bias, the bias voltage required by amplifier M can be obtained through voltage division, such as... Figure 6 As shown, the detection circuit 61 of the totem pole power factor correction circuit 1c in this embodiment may further include a first voltage divider resistor R4 and a second voltage divider resistor R5. The first voltage divider resistor R4 is electrically connected between the positive input terminal of the amplifier M and the positive terminal of the DC power supply DC_bias, and the second voltage divider resistor R5 is electrically connected between the positive input terminal of the amplifier M and the second terminal 612 of the detection circuit 61. In some embodiments, the DC power supply DC_bias, in addition to providing a positive bias voltage to the amplifier M, may also simultaneously power the control unit 7.

[0087] Of course, in some embodiments, the totem pole power factor correction circuit may also include six switching elements, a detection circuit with filtering elements and voltage divider elements, such as... Figure 7 As shown, where Figure 7 This is a circuit topology diagram of the totem pole power factor correction circuit according to the fifth embodiment of this case. The totem pole power factor correction circuit 1d of this embodiment includes six switching elements (i.e., the first switching element S1 and the second switching element S2 of the second bridge arm 3, the third switching element S3 and the fourth switching element S4 of the third bridge arm 4, and the fifth switching element S5 and the sixth switching element S6 of the fourth bridge arm 5), and its circuit structure is similar to that described above. Figure 5 The embodiments described herein will not be repeated here. Furthermore, the detection circuit 61 of the totem pole power factor correction circuit 1d in this embodiment includes a filter resistor Rf, a filter capacitor Cf, a Zener diode ZD, a first voltage divider resistor R4, and a second voltage divider resistor R5, and its circuit structure is similar to that described above. Figure 6 The embodiments are as described above, so they will not be repeated here.

[0088] In some embodiments, the number of bypass diodes in the totem-pole power factor correction circuit can be adjusted according to actual needs, and is not limited to, for example... Figure 1 The two bypass diodes are shown. Please refer to [link / reference]. Figure 8 This is the circuit topology diagram of the totem pole power factor correction circuit in the sixth embodiment of this case. Compared to Figure 1The totem pole power factor correction circuit 1 shown only includes two bypass diodes (i.e., the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2). The totem pole power factor correction circuit 1e in this embodiment includes four bypass diodes, that is, in addition to the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2, it also includes a third bypass diode D3 and a fourth bypass diode D4. The third bypass diode D3 and the fourth bypass diode D4 are connected in series between the positive output terminal Vo+ and the negative output terminal Vo- to form the fifth bridge arm. 8. The fifth bridge arm 8 is connected in parallel with the first bridge arm 2, the second bridge arm 3, the third bridge arm 4, and the fourth bridge arm 5. The connection point between the third bypass diode D3 and the fourth bypass diode D4 forms the fifth connection point E. The fifth connection point E is electrically connected to the second terminal 12 of the input power supply Vac. The third bypass diode D3 and the fourth bypass diode D4 of the fifth bridge arm 8, the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2 are used to precharge the output capacitor Co before the totem pole power factor correction circuit 1e operates.

[0089] Of course, in some embodiments, the number of switching elements and the number of bypass diodes in the totem pole power factor correction circuit can be adjusted simultaneously according to actual needs. Please refer to [link to relevant documentation]. Figure 9 This is the circuit topology diagram of the totem pole power factor correction circuit in the seventh embodiment of this case. Compared to Figure 8The totem pole power factor correction circuit 1e shown only includes four switching elements (i.e., the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4). The totem pole power factor correction circuit 1f in this embodiment includes six switching elements, namely, in addition to the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4, it also includes a fifth switching element S5 and a sixth switching element S6. The fifth switching element S5 and the sixth switching element S6 are connected in series to the positive output terminal Vo+ and the negative output terminal Vo. The fourth bridge arm 5 is formed by connecting the first bridge arm 2, the second bridge arm 3, and the third bridge arm 4. The connection point between the fifth switching element S5 and the sixth switching element S6 forms the fourth connection point D. The fifth switching element S5 and the sixth switching element S6 are electrically connected to the control unit 7 through a drive module (not shown). The control unit 7 then controls the conduction or deactivation of the fifth switching element S5 and the sixth switching element S6. The operation mode of the fifth switching element S5 and the sixth switching element S6 in the fourth bridge arm 5 is similar to that of the first switching element S1 and the second switching element S2 in the second bridge arm 3, so it will not be described again here. In this embodiment, the fifth switching element S5 and the sixth switching element S6 can be gallium nitride (GaN), silicon carbide (SiC), or metal oxide semiconductor field-effect transistor (MOSFET), respectively. The totem pole power factor correction circuit 1f in this embodiment further includes a second inductor L2, which is electrically connected between the first terminal 11 of the input power supply Vac and the fourth connection point D.

[0090] In some embodiments, the location of the detection module in the totem pole power factor correction circuit can also be adjusted as needed. Please refer to [link / reference]. Figure 10 This is the circuit topology diagram of the totem pole power factor correction circuit in the eighth embodiment of this case. Compared to Figure 1In the totem pole power factor correction circuit 1 shown, the first terminal 601 of the detection resistor Res in the detection module 6 is electrically connected to the anode of the first bypass diode D1, and the second terminal 602 of the detection circuit Res is electrically connected to the first terminal 11 of the input power supply Vac. In this embodiment, the first terminal 601 of the detection resistor Res in the detection module 6 of the totem pole power factor correction circuit 1g is electrically connected to the second terminal 12 of the input power supply Vac, and the second terminal 602 of the detection resistor Res is electrically connected to the third connection point C. The first terminal 611 of the detection circuit 61, the first terminal 601 of the detection circuit Res, and the input power supply Vac are connected together. The second terminal 12 of c is connected together. The second terminal 612 of the detection circuit 61, the second terminal 602 of the detection resistor Res, and the third connection point are all connected and grounded. The third terminal 613 of the detection circuit 61 is electrically connected to the control unit 7. When the current supplied by the input power supply Vac flows through the detection resistor Res, the voltage difference across the detection resistor Res is detected by the first terminal 611 and the second terminal 612 of the detection circuit 61. The detection circuit 61 further outputs an output voltage based on the voltage difference across the detection resistor Res, and transmits the output voltage to the control unit 7 through the third terminal 613 of the detection circuit 61. The control unit 7 is electrically connected to the third terminal 613 of the detection circuit 61 to control all switching elements (i.e., the first switching element S1, the second switching element S2, the third switching element S3, and the fourth switching element S4). The control unit 7 controls the corresponding switching element to be turned on or off based on whether the output voltage from the third terminal of the detection circuit 61 is between the upper voltage threshold and the lower voltage threshold. One output terminal of the control unit 7 is grounded. Furthermore, in this embodiment, the first inductor L1 is electrically connected between the first terminal 11 of the input power supply Vac and the second connection point B. In some embodiments, the detection circuit 61 of the totem pole power factor correction circuit 1g may further include an amplifier M, a first resistor R1, a second resistor R2, a third resistor R3, a DC power supply DC_bias, a filter resistor Rf, a filter capacitor Cf, a Zener diode ZD, a first voltage divider resistor R4, and a second voltage divider resistor R5, and its circuit structure is similar to that described above. Figure 4 and Figure 6 The embodiments described herein will not be repeated here. In some embodiments, when the control unit 7 confirms that the output voltage of the detection circuit 61 is between the lower voltage threshold and the upper voltage threshold, the totem pole power factor correction circuit 1g is controlled to be in normal working state. At this time, the current flow topology diagram of the totem pole power factor correction circuit 1g when the power supply voltage provided by the input power supply is in the positive half-cycle and the current flow topology diagram when the power supply voltage provided by the input power supply is in the negative half-cycle are similar to those described above. Figure 2A , Figure 2B , Figure 3A and Figure 3B The embodiments described herein will not be repeated here.

[0091] Of course, in some embodiments, the location of the detection module of the power factor correction circuit and the number of switching elements can be adjusted simultaneously according to actual needs. Please refer to [link / reference]. Figure 11 This is the circuit topology diagram of the totem pole power factor correction circuit in the ninth embodiment of this case. Compared to Figure 10 The totem pole power factor correction circuit 1g shown only contains four switching elements (i.e., the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4). The totem pole power factor correction circuit 1h in this embodiment contains six switching elements, that is, in addition to the first switching element S1 and the second switching element S2 of the second bridge arm 3, and the third switching element S3 and the fourth switching element S4 of the third bridge arm 4, it also includes a fifth switching element S5 and a sixth switching element S6. The fifth switching element S5 and the sixth switching element S6 are connected in series to the positive output terminal Vo+ and the negative output terminal Vo. The fourth bridge arm 5 is formed by connecting the first bridge arm 2, the second bridge arm 3, and the third bridge arm 4. The connection point between the fifth switching element S5 and the sixth switching element S6 forms the fourth connection point D. The fifth switching element S5 and the sixth switching element S6 are electrically connected to the control unit 7 through a drive module (not shown). The control unit 7 then controls the conduction or deactivation of the fifth switching element S5 and the sixth switching element S6. The operation mode of the fifth switching element S5 and the sixth switching element S6 in the fourth bridge arm 5 is similar to that of the first switching element S1 and the second switching element S2 in the second bridge arm 3, so it will not be described again here. In this embodiment, the fifth switching element S5 and the sixth switching element S6 can be gallium nitride (GaN), silicon carbide (SiC), or metal oxide semiconductor field-effect transistor (MOSFET), respectively. The totem pole power factor correction circuit 1h in this embodiment further includes a second inductor L2, which is electrically connected between the first terminal 11 of the input power supply Vac and the fourth connection point D. In some embodiments, the detection circuit 61 of the totem pole power factor correction circuit 1h may further include an amplifier M, a first resistor R1, a second resistor R2, a third resistor R3, a DC power supply DC_bias, a filter resistor Rf, a filter capacitor Cf, a Zener diode ZD, a first voltage divider resistor R4, and a second voltage divider resistor R5, and its circuit structure is similar to that described above. Figure 4 and Figure 6 The embodiments are as described above, so they will not be repeated here.

[0092] Of course, in some embodiments, the location of the detection module of the power factor correction circuit and the number of bypass diodes can also be adjusted as needed. Please refer to [link / reference needed]. Figure 12 This is the circuit topology diagram of the totem pole power factor correction circuit of the tenth embodiment of this case. Compared to Figure 10The totem pole power factor correction circuit 1g shown only includes two bypass diodes (i.e., the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2). The totem pole power factor correction circuit 1i of this embodiment includes four bypass diodes: in addition to the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2, it also includes a third bypass diode D3 and a fourth bypass diode D4. The third bypass diode D3 and the fourth bypass diode D4 are connected in series between the positive output terminal Vo+ and the negative output terminal Vo- to form the fifth bridge arm 8. The fifth bridge arm 8 and the first bridge arm 2... The second bridge arm 3 and the third bridge arm 4 are connected in parallel, and the connection point between the third bypass diode D3 and the fourth bypass diode D4 forms the fifth connection point E. The fifth connection point E is electrically connected to the second terminal 602 of the detection resistor Res, that is, the fifth connection point E is electrically connected to the second terminal 12 of the input power supply Vac via the detection resistor Res. The third bypass diode D3 and the fourth bypass diode D4 of the fifth bridge arm 8, and the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2 are used to precharge the output capacitor Co before the totem pole power factor correction circuit 1e operates. In some embodiments, the detection circuit 61 of the totem pole power factor correction circuit 1i may also include an amplifier M, a first resistor R1, a second resistor R2, a third resistor R3, a DC power supply DC_bias, a filter resistor Rf, a filter capacitor Cf, a Zener diode ZD, a first voltage divider resistor R4, and a second voltage divider resistor R5, and its circuit structure is similar to that described above. Figure 4 and Figure 6 The embodiments are as described above, so they will not be repeated here.

[0093] Of course, in some embodiments, the location of the detection module of the power factor correction circuit, the number of switching elements, and the number of bypass diodes can be adjusted simultaneously according to actual needs. Please refer to [link / reference]. Figure 13 This is the circuit topology diagram of the totem pole power factor correction circuit in the eleventh embodiment of this case. Compared to Figure 11The totem pole power factor correction circuit 1h shown only includes two bypass diodes (i.e., the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2). The totem pole power factor correction circuit 1j in this embodiment includes four bypass diodes: in addition to the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2, it also includes a third bypass diode D3 and a fourth bypass diode D4. The third bypass diode D3 and the fourth bypass diode D4 are connected in series between the positive output terminal Vo+ and the negative output terminal Vo- to form the fifth bridge arm 8. The fifth bridge arm 8, together with the first bridge arm 2 and the second bridge arm 2, forms the fifth bridge arm 8. Arm 3, third bridge arm 4, and fourth bridge arm 5 are connected in parallel, and the connection point between the third bypass diode D3 and the fourth bypass diode D4 forms the fifth connection point E. The fifth connection point E is electrically connected to the second terminal 602 of the detection resistor Res, that is, the fifth connection point E is electrically connected to the second terminal 12 of the input power supply Vac via the detection resistor Res. The third bypass diode D3 and the fourth bypass diode D4 of the fifth bridge arm 8, and the first bypass diode D1 and the second bypass diode D2 of the first bridge arm 2 are used to precharge the output capacitor Co before the totem pole power factor correction circuit 1e operates. In some embodiments, the detection circuit 61 of the totem pole power factor correction circuit 1j may also include an amplifier M, a first resistor R1, a second resistor R2, a third resistor R3, a DC power supply DC_bias, a filter resistor Rf, a filter capacitor Cf, a Zener diode ZD, a first voltage divider resistor R4, and a second voltage divider resistor R5, and its circuit structure is similar to that described above. Figure 4 and Figure 6 The embodiments are as described above, so they will not be repeated here.

[0094] In summary, the detection module of the totem pole power factor correction circuit in this case includes a detection resistor and a detection circuit. When the control unit confirms that the output voltage of the detection circuit is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, the control unit controls at least the third and fourth switching elements to turn off. That is, by comparing the output voltage of the detection circuit with an upper voltage threshold and a lower voltage threshold, it is determined whether the totem pole power factor correction circuit is working normally. When the output voltage of the detection circuit is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold, it can be determined that the totem pole power factor correction circuit is working abnormally (e.g., short circuit). The control unit then controls at least some of the switching elements to turn off to protect the totem pole power factor correction circuit. Therefore, when the voltage of the input power supply suddenly reverses due to sudden events such as lightning, and the control fails to keep up due to delay, or when the switching element is erroneously triggered, causing a short circuit in the input power supply, the totem pole power factor correction circuit in this case can quickly control the corresponding switching element to turn off based on whether the output voltage of the detection circuit is greater than or equal to the upper voltage threshold or less than or equal to the lower voltage threshold. This means that the totem pole power factor correction circuit in this case can take protective measures in time to avoid damage to the totem pole power factor correction circuit. Therefore, the totem pole power factor correction circuit in this case has the advantage of better performance.

Claims

1. A totem-pole power factor correction circuit electrically coupled between an input power supply and a load, the input power supply having a first terminal and a second terminal, the totem-pole power factor correction circuit comprising: A first bridge arm includes a first bypass diode and a second bypass diode connected in series, and the connection point between the first bypass diode and the second bypass diode forms a first connection point; A second bridge arm is connected in parallel with the first bridge arm and includes a first switching element and a second switching element connected in series, wherein the connection point between the first switching element and the second switching element forms a second connection point; A third bridge arm is connected in parallel with the first bridge arm and includes a third switching element and a fourth switching element connected in series. The connection point between the third switching element and the fourth switching element forms a third connection point, which is electrically connected to the second terminal of the input power supply. A first inductor is electrically connected between the first terminal of the input power supply and the second connection point; A detection module includes a detection resistor and a detection circuit, the detection resistor includes a first end and a second end, the detection circuit includes a first end, a second end and a third end, wherein, The first terminal of the sensing resistor, the first connection point, and the first terminal of the sensing circuit are all connected together; the second terminal of the sensing resistor, the first terminal of the input power supply, and the second terminal of the sensing circuit are all connected together. A control unit is electrically coupled to the third terminal of the detection circuit to control the first switching element, the second switching element, the third switching element, and the fourth switching element. The detection circuit detects the voltage difference across the detection resistor and outputs an output voltage from the third terminal of the detection circuit. When the control unit confirms that the output voltage of the detection circuit is greater than or equal to an upper voltage threshold or less than or equal to a lower voltage threshold, the control unit controls at least the third switching element and the fourth switching element to turn off.

2. The totem pole power factor correction circuit as described in claim 1, wherein when the control unit confirms that the output voltage of the detection circuit is greater than or equal to the upper voltage threshold, or less than or equal to the lower voltage threshold, the control unit controls the first switching element, the second switching element, the third switching element and the fourth switching element to turn off.

3. The totem pole power factor correction circuit as described in claim 1, wherein the detection circuit includes an amplifier, a first resistor, a second resistor, a third resistor, and a DC power supply; an output terminal of the amplifier is electrically coupled to the third terminal of the detection circuit; the first resistor is electrically connected between a negative input terminal of the amplifier and the first terminal of the detection circuit; the second resistor is electrically connected between a positive input terminal of the amplifier and the second terminal of the detection circuit; the third resistor is electrically connected between the negative input terminal of the amplifier and the output terminal of the amplifier; the positive terminal of the DC power supply is electrically coupled to the positive input terminal of the amplifier; and the negative terminal of the DC power supply is electrically connected to the second terminal of the detection circuit and grounded.

4. The totem pole power factor correction circuit as described in claim 3, wherein the detection circuit further includes a filter resistor and a filter capacitor, the filter resistor being electrically connected between the output terminal of the amplifier and the third terminal of the detection circuit, and the filter capacitor being electrically connected between the filter resistor and the second terminal of the detection circuit.

5. The totem pole power factor correction circuit as described in claim 4, wherein the detection circuit further includes a Zener diode, the anode of which is electrically connected to the second terminal of the detection circuit, and the cathode of which is electrically connected to the third terminal of the detection circuit.

6. The totem pole power factor correction circuit as described in claim 3, wherein the detection circuit includes a first voltage divider resistor and a second voltage divider resistor, the first voltage divider resistor being electrically connected between the positive input terminal of the amplifier and the positive terminal of the DC power supply, and the second voltage divider resistor being electrically connected between the positive input terminal of the amplifier and the second terminal of the detection circuit.

7. The totem pole power factor correction circuit as claimed in claim 1, wherein the totem pole power factor correction circuit further includes a fourth bridge arm and a second inductor, the fourth bridge arm being connected in parallel with the first bridge arm, and including a fifth switching element and a sixth switching element connected in series, the fifth switching element and the sixth switching element being electrically connected to form a fourth connection point, and the second inductor being electrically connected between the first terminal of the input power supply and the fourth connection point.

8. The totem pole power factor correction circuit as described in claim 1 or 7, wherein the totem pole power factor correction circuit further includes a fifth bridge arm, the fifth bridge arm including a third bypass diode and a fourth bypass diode connected in series, the connection point between the third bypass diode and the fourth bypass diode forming a fifth connection point, the fifth connection point being electrically connected to the second terminal of the input power supply.

9. The totem pole power factor correction circuit as described in claim 1, wherein when the power supply voltage provided by the input power supply is the positive half-cycle of the AC voltage and the first inductor is in the energy storage stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the second switching element and the fourth switching element to be turned on, and the first switching element and the third switching element to be turned off.

10. The totem pole power factor correction circuit as claimed in claim 1, wherein when the power supply voltage provided by the input power supply is the positive half-cycle of the AC voltage and the first inductor is in the discharge stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the first switching element and the fourth switching element to be turned on, and the second switching element and the third switching element to be turned off.

11. The totem pole power factor correction circuit as claimed in claim 1, wherein when the power supply voltage provided by the input power supply is the negative half-cycle of the AC voltage and the first inductor is in the energy storage stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the first switching element and the third switching element to be turned on, and the second switching element and the fourth switching element to be turned off.

12. The totem pole power factor correction circuit as claimed in claim 1, wherein when the power supply voltage provided by the input power supply is the negative half-cycle of the AC voltage and the first inductor is in the discharge stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the second and third switching elements to be turned on, and the first and fourth switching elements to be turned off.

13. A totem-pole power factor correction circuit electrically coupled between an input power supply and a load, the input power supply having a first terminal and a second terminal, the totem-pole power factor correction circuit comprising: A first bridge arm includes a first bypass diode and a second bypass diode connected in series. The connection point between the first bypass diode and the second bypass diode forms a first connection point, which is electrically connected to the first terminal of the input power supply. A second bridge arm is connected in parallel with the first bridge arm and includes a first switching element and a second switching element connected in series, wherein the connection point between the first switching element and the second switching element forms a second connection point; A third bridge arm is connected in parallel with the first bridge arm and includes a third switching element and a fourth switching element connected in series, wherein the connection point between the third switching element and the fourth switching element forms a third connection point; A first inductor is electrically connected between the first terminal of the input power supply and the second connection point; A detection module includes a detection resistor and a detection circuit. The detection resistor includes a first terminal and a second terminal, and the detection circuit includes a first terminal, a second terminal, and a third terminal. The first terminal of the sensing resistor, the second terminal of the input power supply, and the first terminal of the sensing circuit are all connected together; the second terminal of the sensing resistor, the third connection point, and the second terminal of the sensing circuit are all connected together; and A control unit is electrically coupled to the third terminal of the detection circuit to control the first switching element, the second switching element, the third switching element, and the fourth switching element. The detection circuit detects the voltage difference across the detection resistor and outputs an output voltage from the third terminal of the detection circuit. When the control unit confirms that the output voltage of the detection circuit is greater than or equal to an upper voltage threshold or less than or equal to a lower voltage threshold, the control unit controls at least the third switching element and the fourth switching element to turn off.

14. The totem pole power factor correction circuit as described in claim 13, wherein when the control unit confirms that the output voltage of the detection circuit is greater than or equal to the upper voltage threshold, or less than or equal to the lower voltage threshold, the control unit controls the first switching element, the second switching element, the third switching element, and the fourth switching element to turn off.

15. The totem pole power factor correction circuit as described in claim 13, wherein the detection circuit includes an amplifier, a first resistor, a second resistor, a third resistor, and a DC power supply; an output terminal of the amplifier is electrically coupled to the third terminal of the detection circuit; the first resistor is electrically connected between a negative input terminal of the amplifier and the first terminal of the detection circuit; the second resistor is electrically connected between a positive input terminal of the amplifier and the second terminal of the detection circuit; the third resistor is electrically connected between the negative input terminal of the amplifier and the output terminal of the amplifier; the positive terminal of the DC power supply is electrically coupled to the positive input terminal of the amplifier; and the negative terminal of the DC power supply is electrically connected to the second terminal of the detection circuit and grounded.

16. The totem pole power factor correction circuit as described in claim 15, wherein the detection circuit further includes a filter resistor and a filter capacitor, the filter resistor being electrically connected between the output terminal of the amplifier and the third terminal of the detection circuit, and the filter capacitor being electrically connected between the filter resistor and the second terminal of the detection circuit.

17. The totem pole power factor correction circuit as described in claim 16, wherein the detection circuit further includes a Zener diode, the anode of which is electrically connected to the second terminal of the detection circuit, and the cathode of which is electrically connected to the third terminal of the detection circuit.

18. The totem pole power factor correction circuit as described in claim 15, wherein the detection circuit includes a first voltage divider resistor and a second voltage divider resistor, the first voltage divider resistor being electrically connected between the positive input terminal of the amplifier and the positive terminal of the DC power supply, and the second voltage divider resistor being electrically connected between the positive input terminal of the amplifier and the second terminal of the detection circuit.

19. The totem pole power factor correction circuit as claimed in claim 13, wherein the totem pole power factor correction circuit further includes a fourth bridge arm and a second inductor, the fourth bridge arm being connected in parallel with the first bridge arm, and including a fifth switching element and a sixth switching element connected in series, the fifth switching element and the sixth switching element being electrically connected to form a fourth connection point, and the second inductor being electrically connected between the first terminal of the input power supply and the fourth connection point.

20. The totem pole power factor correction circuit as described in claim 13 or 19, wherein the totem pole power factor correction circuit further includes a fifth bridge arm, the fifth bridge arm including a third bypass diode and a fourth bypass diode connected in series, the connection point between the third bypass diode and the fourth bypass diode forming a fifth connection point, the fifth connection point being electrically connected to the third connection point.

21. The totem pole power factor correction circuit as described in claim 13, wherein when the power supply voltage provided by the input power supply is the positive half-cycle of the AC voltage and the first inductor is in the energy storage stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the second switching element and the fourth switching element to be turned on, and the first switching element and the third switching element to be turned off.

22. The totem pole power factor correction circuit as described in claim 13, wherein when the power supply voltage provided by the input power supply is the positive half-cycle of the AC voltage and the first inductor is in the discharge stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the first switching element and the fourth switching element to be turned on, and the second switching element and the third switching element to be turned off.

23. The totem pole power factor correction circuit as described in claim 13, wherein when the power supply voltage provided by the input power supply is the negative half-cycle of the AC voltage and the first inductor is in the energy storage stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the first switching element and the third switching element to be turned on, and the second switching element and the fourth switching element to be turned off.

24. The totem pole power factor correction circuit as described in claim 13, wherein when the power supply voltage provided by the input power supply is the negative half-cycle of the AC voltage and the first inductor is in the discharge stage, the control unit further confirms that when the voltage across the detection resistor detected by the detection circuit is between the lower voltage threshold and the upper voltage threshold, the control unit controls the second and third switching elements to be turned on, and the first and fourth switching elements to be turned off.

Images