Totem-pole bridgeless circuit and power module

Abstract

The embodiment of the present application relates to the field of power electronics, and discloses a totem pole bridgeless circuit and a power module, the totem pole bridgeless circuit comprising a current sampling unit, a current processing unit, a bridge arm unit and a control unit, the control unit comprising an analog-to-digital converter and a controller, the current processing unit obtaining a current sampling signal through the current sampling unit and obtaining a DC bias voltage of the current sampling unit, and then superimposing the current sampling signal and the DC bias voltage to obtain a steamed bun wave current signal, so that the control unit can output a driving signal to the switching device according to the steamed bun wave current signal, thereby realizing loop control of the current in the power module, and the circuit has simple structure and small current sampling error.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to a totem pole bridgeless circuit and power supply module. Background Technology

[0002] In energy conversion systems, power conversion efficiency is a crucial parameter for evaluating the system. Compared to traditional power conversion circuits, bridgeless circuits can eliminate some or all diodes, thereby reducing circuit conduction losses and offering advantages in high-efficiency energy conversion. Totem-pole bridgeless circuits, as a type of bridgeless circuit, possess advantages such as simple circuit structure and high conversion efficiency, and have been increasingly widely used in recent years.

[0003] In the process of implementing the embodiments of the present invention, the inventors have discovered at least the following problems in the above-mentioned related technologies: Currently, in the digital control part of the totem pole bridgeless circuit, the control unit needs to collect the AC input current signal through an analog-to-digital converter. However, since the current sampling device will also generate a certain DC bias voltage, the collected AC input current signal needs to be further processed before it can be used for loop control. In the existing totem pole bridgeless circuit, the controller usually needs to occupy a lot of resources to achieve current sampling, and it is difficult to solve the error problem caused by the DC bias voltage. Summary of the Invention

[0004] This application provides a totem pole bridgeless circuit and power supply module.

[0005] The objective of this invention is achieved through the following technical solutions:

[0006] To address the aforementioned technical problems, in a first aspect, this invention provides a totem pole bridgeless circuit, comprising: a current sampling unit connected to the AC input terminal of the totem pole bridgeless circuit, used to collect the AC input current of the totem pole bridgeless circuit and convert it into a current sampling signal; a current processing unit, whose first input terminal is connected to the output terminal of the current sampling unit to obtain the current sampling signal, and whose second input terminal is connected to the power input terminal of the current sampling unit to obtain a DC bias voltage, the current processing unit being configured to superimpose the AC input current and the DC bias voltage to obtain a wavy current signal; a bridge arm unit, whose input terminal is connected to an AC power supply, and whose output terminal is used to output DC power; and a control unit, comprising an analog-to-digital converter and a controller, the input terminal of the analog-to-digital converter being connected to the output terminal of the current processing unit, the controller being connected to a switching device in the bridge arm unit, and the control unit being configured to output a drive signal to the switching device according to the wavy current signal.

[0007] In some embodiments, the current sampling unit includes: a Hall sensor, the input of which is connected to the AC input of the totem pole bridgeless circuit, the output of which is connected to the first input of the current processing unit, and the power input of which is connected to the second input of the current processing unit; and a bias voltage divider circuit, the input of which is connected to a DC power supply, and the output of which is connected to the power input of the Hall sensor.

[0008] In some embodiments, the current sampling unit includes: a current sampling resistor connected between the AC power supply and the AC input terminal of the totem-pole bridgeless circuit; an isolation operational amplifier whose input terminal is connected to the current sampling resistor, whose output terminal is connected to the first input terminal of the current processing unit, and whose power input terminal is connected to the second input terminal of the current processing unit; and a bias voltage divider circuit whose input terminal is connected to the DC power supply, and whose output terminal is connected to the power input terminal of the isolation operational amplifier.

[0009] In some embodiments, the bias voltage divider circuit includes: two voltage divider resistors connected in series, one end of which is connected to the DC power supply and to the power input terminal of the Hall sensor or the isolation operational amplifier, the other end of which is grounded, and the second input terminal of the current processing unit is connected to the connection point between the two voltage divider resistors; and a filter capacitor connected in parallel across the two voltage divider resistors.

[0010] In some embodiments, the current processing unit includes: an operational amplifier whose output is connected to the analog-to-digital converter; a first polarity switching switch whose input is connected to the output of the current sampling unit, wherein the output of the first polarity switching switch is configured to be connected to the positive input of the operational amplifier during the positive half-cycle of the AC power output and to the inverting input of the operational amplifier during the negative half-cycle of the AC power output; and a second polarity switching switch whose input is connected to the power input of the current sampling unit, wherein the output of the second polarity switching switch is configured to be connected to the inverting input of the operational amplifier during the positive half-cycle of the AC power output and to the positive input of the operational amplifier during the negative half-cycle of the AC power output.

[0011] In some embodiments, the totem pole bridgeless circuit further includes: a voltage sampling unit, the input terminal of which is connected to the AC input terminal of the totem pole bridgeless circuit, the first output terminal of which is connected to the control terminal of the first polarity switching switch, and the second output terminal of which is connected to the control terminal of the second polarity switching switch.

[0012] In some embodiments, the totem pole bridgeless circuit further includes: a voltage sampling unit, the first input terminal of which is connected to the output terminal of the current sampling unit, the second input terminal of which is connected to the power input terminal of the current sampling unit, the first output terminal of which is connected to the control terminal of the first polarity switching switch, and the second output terminal of which is connected to the control terminal of the second polarity switching switch.

[0013] In some embodiments, the totem pole bridgeless circuit further includes: a fast overcurrent protection unit, the input of which is connected to the output of the operational amplifier, and the output of which is connected to the input of the controller.

[0014] In some embodiments, the control unit further includes a power factor correction circuit, the input of which is connected to the output of the analog-to-digital converter, and the output of which is connected to the controller.

[0015] To address the aforementioned technical problems, in a second aspect, this invention provides a power supply module, characterized in that it includes: a totem pole bridgeless circuit as described in the first aspect.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: Unlike the prior art, the embodiments of the present invention provide a totem pole bridgeless circuit and a power supply module. The totem pole bridgeless circuit includes a current sampling unit, a current processing unit, a bridge arm unit, and a control unit. The control unit includes an analog-to-digital converter and a controller. The current processing unit obtains the current sampling signal through the current sampling unit and obtains the DC bias voltage of the current sampling unit. Then, the current sampling signal and the DC bias voltage are superimposed to obtain a steampunk wave current signal, so that the control unit can output a drive signal to the switching device according to the steampunk wave current signal, thereby realizing the loop control of the current in the power supply module. Moreover, the circuit structure is simple and the sampling current error is small. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements / modules with the same reference numerals in the drawings are represented as similar elements / modules. Unless otherwise stated, the figures in the drawings do not constitute a limitation on scale.

[0018] Figure 1 This is a structural block diagram of a totem pole bridgeless circuit provided in an embodiment of the present invention;

[0019] Figure 2 This is a structural block diagram of another totem pole bridgeless circuit provided in an embodiment of the present invention;

[0020] Figure 3 yes Figure 2The circuit diagram shown represents a circuit structure of a current sampling unit, a current processing unit, a voltage sampling unit, and a fast overcurrent protection unit.

[0021] Figure 4 yes Figure 2 Another circuit structure diagram of the current sampling unit, current processing unit, voltage sampling unit and fast overcurrent protection unit in the circuit shown.

[0022] Figure 5 yes Figure 2 The diagram shown is an electrical connection structure diagram of a totem pole bridgeless circuit;

[0023] Figure 6 yes Figure 2 Another circuit structure diagram of the current sampling unit, current processing unit, voltage sampling unit and fast overcurrent protection unit in the circuit shown.

[0024] Figure 7 yes Figure 3 The sampling waveform diagram of the circuit shown;

[0025] Figure 8 This is a structural diagram of a power module provided in an embodiment of the present invention.

[0026] Figure descriptions: 100, Totem pole bridgeless circuit; 110, Current sampling unit; 120, Current processing unit; 130, Bridge arm unit; 140, Control unit; 150, Voltage sampling unit; 160, Fast overcurrent protection unit; V CS Current sampling signal; Hall sensor; V DD DC power supply; R S 1. Current sampling resistor; U0. Isolation operational amplifier; 111. Bias voltage divider circuit; AC. AC power supply; R1 / R2. Voltage divider resistors; C S Filter capacitor; V CS_REF DC bias voltage; U1, operational amplifier; S1, first polarity switch; S2, second polarity switch; ADC, analog-to-digital converter; SR1, first slow-speed switch; SR2, second slow-speed switch; Q1, first fast-speed switch; Q2, second fast-speed switch; L1, input inductor; C1, output filter capacitor; R L Output load; CNTLR; controller; 141; power factor correction circuit; V OC_REF Reference signal; V AC AC input voltage; V ACL The voltage of the AC power supply live wire; V ACN The voltage of the neutral wire of the AC power supply; I AC AC input current; I AC_FB10. Current of the steamed bun wave signal; 11. Power supply module. Detailed Implementation

[0027] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0029] It should be noted that, unless otherwise specified, the various features in the embodiments of the present invention can be combined with each other, all within the scope of protection of this application. Furthermore, although functional modules are divided in the device schematic diagram, in some cases, the module division may differ from that in the device. When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements.

[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0031] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] To address the issues of significant errors caused by the DC bias voltage of the current sampling device in current totem-pole bridgeless circuits, and the excessive processor / controller resource consumption during the processing of sampled AC input current, this invention provides a totem-pole bridgeless circuit. This circuit directly acquires the DC bias voltage of the current sampling unit and superimposes it with the current sampling signal collected by the current sampling unit, reducing errors caused by the DC bias current. The resulting waveform signal can be directly output to the control unit via an analog-to-digital converter (ADC), eliminating the need for further processing and conserving processing resources. Furthermore, since the ADC in the control unit can directly receive and process the waveform signal, a wide sampling range ADC is not required. Additionally, the waveform current signal output by the current processing unit can be directly used for rapid overcurrent protection, etc.

[0033] Specifically, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0034] This invention provides a totem pole bridgeless circuit; please refer to [link / reference]. Figure 1 The diagram illustrates a structural block diagram of a totem pole bridgeless circuit 100 provided by an embodiment of the present invention. The totem pole bridgeless circuit 100 includes: a current sampling unit 110, a current processing unit 120, a bridge arm unit 130, and a control unit 140. Further details can be found in the following documentation. Figure 2 The diagram shows a structural block diagram of another totem pole bridgeless circuit provided in an embodiment of the present invention. The totem pole bridgeless circuit 100 may further include: a voltage sampling unit 150 and a fast overcurrent protection unit 160.

[0035] The totem pole bridgeless circuit 100 provided in this embodiment of the invention, when converting AC power to DC output through the bridge arm unit 130, can acquire the AC input current through the current sampling unit 110 and convert it into a current sampling signal. After the current sampling signal is processed into a wave signal by the current processing unit 120, it can be directly used as the adjustment parameter for loop control. The control unit 140 can adjust the driving signal of the switching device according to the wave signal and send the driving signal to the bridge arm unit 130 to achieve closed-loop adjustment. At the same time, the AC input voltage can also be acquired through the voltage sampling unit 150 to determine the working cycle of the AC power supply, so that the current processing unit 120 can adjust the polarity of the output signal accordingly. In addition, the signal processed by the current processing unit 120 can also be directly input to the fast overcurrent protection unit 160 to achieve fast overcurrent protection.

[0036] The current sampling unit 110 is connected to the AC input terminal of the totem pole bridgeless circuit 100 and is used to collect the AC input current I of the totem pole bridgeless circuit 100. ACIt should be noted that the current sampling unit 110 can collect the AC input current I of the totem pole bridgeless circuit 100, in addition to... AC It can also be configured to collect the DC output current of the totem pole bridgeless circuit 100 as needed, and / or to collect the current of any unit in the totem pole bridgeless circuit 100, for example, to collect the current flowing through the switching device of the bridge arm unit 130. The specific settings can be made according to the actual current sampling needs.

[0037] Specifically, please see Figure 3 It shows Figure 2 The totem pole bridgeless circuit shown is a circuit structure comprising a current sampling unit 110, a current processing unit 120, a voltage sampling unit 150, and a fast overcurrent protection unit 160. Figure 3 As shown, the current sampling unit 110 includes a Hall sensor and a bias voltage divider circuit 111. The Hall sensor's input terminal is connected to the AC input terminal of the totem pole bridgeless circuit 100, its output terminal is connected to the first input terminal of the current processing unit 120, and its power input terminal is connected to the second input terminal of the current processing unit 120. The bias voltage divider circuit 111's input terminal is connected to the DC power supply V. DD The output terminal of the Hall sensor is connected to the power input terminal of the Hall sensor. The Hall sensor collects the AC input current I. AC Then, the AC input current I is transmitted through its output terminal. AC Converted to current sampling signal V CS The output is sent to the first input terminal of the current processing unit 120, and the second input terminal of the current processing unit 120 also obtains the DC bias voltage of the Hall sensor through the bias voltage divider circuit 111.

[0038] Alternatively, please see Figure 4 It shows Figure 2 The diagram shows another circuit structure for the current sampling unit 110, current processing unit 120, voltage sampling unit 150, and fast overcurrent protection unit 160 in the totem pole bridgeless circuit. The current sampling unit 110 includes a current sampling resistor R. S 1. Isolation operational amplifier U0, bias voltage divider circuit 111. The current sampling resistor R... S A circuit is connected between the AC power supply AC and the AC input terminal of the totem pole bridgeless circuit 100; an isolation operational amplifier U0, the input terminal of which is connected to the current sampling resistor R. SThe output terminal of the bias voltage divider circuit 111 is connected to the first input terminal of the current processing unit 120, and its power input terminal is connected to the second input terminal of the current processing unit 120; the bias voltage divider circuit 111 has its input terminal connected to the DC power supply V. DD The output terminal is connected to the power input terminal of the isolated operational amplifier U0. Current flows through the current sampling resistor R. S AC input current I AC The signal is converted into a current sampling signal V by the isolation operational amplifier U0. CS The output is sent to the first input terminal of the current processing unit 120, and the second input terminal of the current processing unit 120 also obtains the DC bias voltage of the isolation operational amplifier U0 through the bias voltage divider circuit 111.

[0039] Please continue to see Figure 3 and Figure 4 The bias voltage divider circuit 111 includes two voltage divider resistors R1 and R2 connected in series. One end of the two voltage divider resistors R1 and R2 (i.e., the end of voltage divider resistor R1 that is not connected to voltage divider resistor R2) is connected to the DC power supply V. DD The connection is made to the power input terminal of the Hall sensor or the isolation operational amplifier U0. The other end of the two series-connected voltage divider resistors R1 and R2 (i.e., the end of voltage divider resistor R2 that is not connected to voltage divider resistor R1) is grounded. The second input terminal of the current processing unit 120 is connected to the connection point between the two voltage divider resistors R1 and R2. Filter capacitor C S The voltage divider resistors R1 and R2 are connected in parallel across the two series-connected voltage divider resistors. Furthermore, R1 and R2 are two high-precision resistors with identical resistance values ​​used to achieve resistive voltage division, ensuring that the DC bias voltage V... CS_REF Satisfy V CS_RFE =V DD *R2 / (R1+R2).

[0040] The current processing unit 120 has its first input terminal connected to the output terminal of the current sampling unit 110 to obtain the current sampling signal V. CS Its second input terminal is connected to the power input terminal of the current sampling unit 110 to obtain the DC bias voltage V. CS_REF The current processing unit 120 is configured to process the input current sampling signal V CS and the DC bias voltage V CS_REF Superimposed to obtain the steamed bun wave current signal; specifically, in Figure 3 and Figure 4 In the process, the DC bias voltage V is acquired through the connection point between the two voltage divider resistors R1 and R2. CS_REFThe current sampling signal V is obtained through the output terminal of the Hall sensor or the output terminal of the isolation operational amplifier U0. CS The current processing unit 120 is capable of processing the sinusoidal current sampling signal V. CS By superimposing a DC bias voltage V CS_REF The waveform is rectified into a bun wave and then output to the control unit 140.

[0041] For details, please continue to see Figure 3 and Figure 4 The current processing unit 120 includes: an operational amplifier U1, a first polarity switching switch S1, and a second polarity switching switch S2. The operational amplifier U1 has its output terminal connected to the analog-to-digital converter (ADC). The first polarity switching switch S1 has its input terminal connected to the output terminal of the current sampling unit 110. The output terminal of the first polarity switching switch S1 is configured to connect to the positive input terminal of the operational amplifier U1 during the positive half-cycle of the AC power supply output and to the inverting input terminal of the operational amplifier U1 during the negative half-cycle of the AC power supply output. The first input terminal of the current processing unit 120 is also the input terminal of the first polarity switching switch S1. The second polarity switching switch S2 has its input terminal connected to the power input terminal of the current sampling unit 110. The output terminal of the second polarity switching switch S2 is configured to connect to the inverting input terminal of the operational amplifier U1 during the positive half-cycle of the AC power supply output and to the positive input terminal of the operational amplifier U1 during the negative half-cycle of the AC power supply output. The second input terminal of the current processing unit 120 is also the input terminal of the second polarity switching switch S2. The current cycle of the AC power supply output can be determined by the voltage sampling unit 150.

[0042] The bridge arm unit 130 has its input terminal connected to an AC power supply and its output terminal for outputting DC power; wherein the AC power supply can be AC ​​mains power or other AC power sources. For details, please refer to [link to relevant documentation]. Figure 5 It shows Figure 2 The diagram shows an electrical connection structure of a totem pole bridgeless circuit 100.

[0043] like Figure 5As shown, the bridge arm unit 130 includes a first slow-speed switch SR1 and a second slow-speed switch SR2 connected in the same direction, as well as a first fast-speed switch Q1 and a second fast-speed switch Q2 connected in the same direction. The reverse recovery time of the first fast-speed switch Q1 and the second fast-speed switch Q2 is shorter than the reverse recovery time of the first slow-speed switch SR1 and the second slow-speed switch SR2. The switching of the first slow-speed switch SR1 and the second slow-speed switch SR2 is synchronized with the frequency of the output voltage of the AC power supply.

[0044] And more, please continue reading. Figure 5 The totem pole bridgeless circuit 100 also includes an input inductor L1, one end of which is connected to an AC power supply, and the other end of which is connected between the first fast switching transistor Q1 and the second fast switching transistor Q2. (See also...) Figure 5 The totem pole bridgeless circuit 100 also includes an output filter capacitor C1 and an output load R. L The output filter capacitor C1 and the output load R L They are connected in parallel to the output side of the bridge arm unit 130.

[0045] When the AC power supply is in the positive half-cycle of output, the input inductor L1, the first fast-switching transistor Q1, and the first slow-switching transistor SR1 can form an energy storage circuit. The AC power supply stores energy in the input inductor L1, and the output filter capacitor C1 and the output load R on the output side... L It also forms a separate current loop; the input inductor L1, the second fast switching transistor Q2, and the first slow switching transistor SR1 can form a freewheeling circuit, and the input inductor L1 is connected to the output filter capacitor C1 and the output load R. L Energy is released. During the negative half-cycle of the AC power supply output, the second slow-speed switch SR2, the second fast-speed switch Q2, and the input inductor L1 form an energy storage circuit. The AC power supply stores energy in the input inductor L1, and the output filter capacitor C1 stores energy in the output load R. L Discharge; the second slow-speed switching transistor SR2, the first fast-speed switching transistor Q1, and the input inductor L1 form a freewheeling circuit. The input inductor L1 connects to the output filter capacitor C1 at the load end and the output load R. L Release energy.

[0046] The control unit 140 can adjust the duty cycle and switching frequency of the first slow-speed switch SR1 by outputting the drive signal SRL, adjust the duty cycle and switching frequency of the second slow-speed switch SR2 by outputting the drive signal SRH, adjust the duty cycle and switching frequency of the first fast-speed switch Q1 by outputting the drive signal PWML, and adjust the duty cycle and switching frequency of the second fast-speed switch Q2 by outputting the drive signal PWMH. Furthermore, the first slow-speed switch SR1 and the second slow-speed switch SR2, as well as the first fast-speed switch Q1 and the second fast-speed switch Q2, can be power switching devices such as thyristors, MOSFETs, and IGBTs. The slow-speed and fast-speed switches can be of the same type / model or different types / models, and can be selected according to actual needs.

[0047] The control unit 140 includes an analog-to-digital converter (ADC) and a controller CNTLR. The input terminal of the ADC is connected to the output terminal of the current processing unit 120, and the controller CNTLR is connected to the switching devices in the bridge arm unit 130. The control unit 140 is configured to output a drive signal to the switching devices based on the swivel current signal. The control unit 140 can combine the polarity, zero-crossing point, and soft-start control of the AC power supply to output the drive signal to each switching device in the bridge arm unit 130 for modulation. Compared to the prior art where the ADC also needs to acquire the DC bias voltage, in this embodiment of the invention, the ADC only needs to convert the rectified swivel signal into a digital signal and output it to the controller CNTLR. Therefore, an ADC with a narrow sampling range and low accuracy can be selected, reducing costs.

[0048] The control unit 140 outputs a pulse width modulation (PWM) signal to... Figure 5 The first slow-speed switching transistor SR1 and the second slow-speed switching transistor SR2, the first fast-speed switching transistor Q1 and the second fast-speed switching transistor Q2 are used to achieve power modulation. The controller CNTLR is configured as a controller device capable of outputting the pulse width modulation signal. It has calculation and judgment functions and can be a PID controller or a microcontroller unit (MCU). The specific model of the controller CNTLR can be selected according to actual needs and does not need to be limited to the embodiments of this invention.

[0049] For details, please continue to see Figure 5The control unit 140 further includes a power factor correction (PFC) circuit 141, whose input terminal is connected to the output terminal of the analog-to-digital converter (ADC), and whose output terminal is connected to the controller CNTLR. Since the AC input voltage and AC input current generally operate in phase, the unbiased swivel signal output by the current processing unit 120 can be directly used for loop control of the power factor correction circuit 141.

[0050] The voltage sampling unit 150 can use the polarity of the AC input voltage or AC input current as a control signal to control the first polarity switching switch S1 and the second polarity switching switch S2. For details, please refer to [link to relevant documentation]. Figure 3 and Figure 6 ,in, Figure 6 It shows Figure 2 This is another circuit structure of the totem pole bridgeless circuit shown, which includes the current sampling unit 110, the current processing unit 120, the voltage sampling unit 150, and the fast overcurrent protection unit 160.

[0051] When the voltage sampling unit 150 uses the polarity of the AC input voltage as the control signal for the first polarity switching switch S1 and the second polarity switching switch S2, please refer to... Figure 3 The voltage sampling unit 150 has its input terminal connected to the AC input terminal of the totem pole bridgeless circuit 100, its first output terminal connected to the control terminal of the first polarity switching switch S1, and its second output terminal connected to the control terminal of the second polarity switching switch S2. The voltage sampling unit 150 is connected to the live wire and neutral wire of the AC power supply through its first and second input terminals, respectively, and acquires the voltage V of the live wire of the AC power supply through its first input terminal. ACL The voltage V of the AC neutral line of the power supply is acquired through the second input terminal. ACN .

[0052] Furthermore, during the positive half-cycle of the AC power supply output, please also refer to... Figure 7 It shows Figure 3 The sampling waveform diagram of the circuit shown, where V AC For the waveform of the AC input voltage, I AC The waveform of the AC input current, V CS_REF The waveform of the DC bias voltage, V OC_REF The voltage of the reference signal for comparator U3, I AC_FB This is the waveform of the current from the output of operational amplifier U1, which is a wavy signal. The voltage V at the first input terminal can be detected by comparator U2. ACL The voltage V higher than the second input terminal ACNAt this time, the comparator U2 outputs a positive polarity signal. The first polarity switch S1 and the second polarity switch S2 are switched on. The first polarity switch S1 connects the output of the current sampling unit 110 to the positive input of the operational amplifier U1, and the second polarity switch S2 connects the power input of the current sampling unit 110 to the inverting input of the operational amplifier U1. The operational amplifier U1 then converts the sinusoidal current sampling signal V... CS and DC bias voltage V CS_REF After superposition, the output is as follows Figure 7 The positive half-cycle of the steamed bun-shaped current signal is shown.

[0053] During the negative half-cycle of the AC power supply output, please continue to refer to... Figure 7 The voltage V at the first input terminal can be detected by comparator U2. ACL The voltage V below the second input terminal ACN At this time, the comparator U2 outputs a negative polarity signal (POLARITY). The first polarity switch S1 and the second polarity switch S2 are switched down. The second polarity switch S2 connects the output terminal of the current sampling unit 110 and the positive input terminal of the operational amplifier U1. The first polarity switch S1 connects the power input terminal of the current sampling unit 110 and the inverting input terminal of the operational amplifier U1. The operational amplifier U1 outputs a negative half-cycle wavy current signal.

[0054] When the voltage sampling unit 150 uses the polarity of the AC input current as the control signal for the first polarity switching switch S1 and the second polarity switching switch S2, please refer to... Figure 6 The voltage sampling unit 150 has its first input terminal connected to the output terminal of the current sampling unit 110, its second input terminal connected to the power input terminal of the current sampling unit 110, its first output terminal connected to the control terminal of the first polarity switching switch S1, and its second output terminal connected to the control terminal of the second polarity switching switch S2.

[0055] Furthermore, during the positive half-cycle of the AC power supply output, please continue to refer to... Figure 7 The voltage V at the first input terminal can be detected by comparator U2. CS The voltage V higher than the second input terminal CS_REFAt this time, the polarity output POLARITY of the comparator U2 is positive, the first polarity switch S1 and the second polarity switch S2 are turned up, the first polarity switch S1 connects the output terminal of the current sampling unit 110 and the positive input terminal of the operational amplifier U1, and the second polarity switch S2 connects the power input terminal of the current sampling unit 110 and the inverting input terminal of the operational amplifier U1. The operational amplifier U1 outputs a positive half-cycle steampunk current signal.

[0056] During the negative half-cycle of the AC power supply output, please continue to refer to... Figure 7 The voltage V at the first input terminal can be detected by comparator U2. CS The voltage V below the second input terminal CS_REF At this time, the comparator U2 outputs a negative polarity signal (POLARITY). The first polarity switch S1 and the second polarity switch S2 are switched down. The second polarity switch S2 connects the output terminal of the current sampling unit 110 and the positive input terminal of the operational amplifier U1. The first polarity switch S1 connects the power input terminal of the current sampling unit 110 and the inverting input terminal of the operational amplifier U1. The operational amplifier U1 outputs a negative half-cycle wavy current signal.

[0057] Please see Figure 3 , Figure 4 , Figure 6 The fast overcurrent protection unit 160 has its input terminal connected to the output terminal of the operational amplifier U1, and its output terminal connected to the input terminal of the controller CNTLR. The swivel signal output by the operational amplifier U1 can be directly used for input overcurrent protection, reducing the delay caused by the sampling of the analog-to-digital converter (ADC) and achieving fast overcurrent protection. Specifically, the fast overcurrent protection unit 160 includes a comparator U3. The output terminal of the operational amplifier U1 is connected to the non-inverting input terminal of the comparator U3, and the inverting input terminal of the comparator U3 receives the reference signal V. OC_REF Please see also Figure 7 The steamed bun wave signal I output by operational amplifier U1 AC_FB The level is higher than the reference signal V. OC_REF When this occurs, the fast overcurrent protection is triggered.

[0058] This invention also provides a power supply module; please refer to [link / reference]. Figure 8 This illustrates the structure of a power module provided in an embodiment of the present invention. The power module 10 includes a totem pole bridgeless circuit 100, which is... Figures 1 to 6 The totem pole bridgeless circuit 100 described in the illustrated embodiment is detailed above and will not be described in detail here.

[0059] When the power module 10 adopts the totem pole bridgeless circuit 100 provided in the embodiment of the present invention, it can realize the rapid and accurate acquisition of current signals, realize the rapid implementation of current loop control, and realize rapid overcurrent protection. Moreover, the circuit structure is simple and the cost is low.

[0060] This invention provides a totem pole bridgeless circuit and a power supply module. The totem pole bridgeless circuit includes a current sampling unit, a current processing unit, a bridge arm unit, and a control unit. The control unit includes an analog-to-digital converter and a controller. The current processing unit acquires a current sampling signal and a DC bias voltage of the current sampling unit through the current sampling unit, and then superimposes the current sampling signal and the DC bias voltage to obtain a wave-shaped current signal. This allows the control unit to output a drive signal to the switching device based on the wave-shaped current signal, thereby realizing loop control of the current within the power supply module. Moreover, the circuit structure is simple and the current sampling error is small.

[0061] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A totem pole bridgeless circuit, characterized in that, include: A current sampling unit is connected to the AC input terminal of the totem pole bridgeless circuit and is used to collect the AC input current of the totem pole bridgeless circuit and convert it into a current sampling signal. The current sampling unit includes a Hall sensor and a bias voltage divider circuit. A current processing unit has a first input terminal connected to the output terminal of the Hall sensor to obtain the current sampling signal, and a second input terminal connected to the power input terminal of the Hall sensor to obtain a DC bias voltage. The current processing unit is configured to superimpose the AC input current and the DC bias voltage to obtain a wavy current signal. The bridge arm unit has its input end connected to an AC power source and its output end used to output DC power. The control unit includes an analog-to-digital converter and a controller. The input terminal of the analog-to-digital converter is connected to the output terminal of the current processing unit, and the controller is connected to the switching device in the bridge arm unit. The control unit is configured to output a drive signal to the switching device according to the swirl current signal. The Hall sensor's input terminal is connected to the AC input terminal of the totem pole bridgeless circuit, its output terminal is connected to the first input terminal of the current processing unit, its power input terminal is connected to the second input terminal of the current processing unit, the bias voltage divider circuit's input terminal is connected to the DC power supply, and its output terminal is connected to the power input terminal of the Hall sensor. The current processing unit includes an operational amplifier, a first polarity switching switch, and a second polarity switching switch. The output terminal of the operational amplifier is connected to the analog-to-digital converter. The input terminal of the first polarity switching switch is connected to the output terminal of the current sampling unit. The output terminal of the first polarity switching switch is configured to be connected to the positive input terminal of the operational amplifier during the positive half-cycle of the AC power output and to the inverting input terminal of the operational amplifier during the negative half-cycle of the AC power output. The input terminal of the second polarity switching switch is connected to the power input terminal of the current sampling unit. The output terminal of the second polarity switching switch is configured to be connected to the inverting input terminal of the operational amplifier during the positive half-cycle of the AC power output and to the positive input terminal of the operational amplifier during the negative half-cycle of the AC power output.

2. The totem pole bridgeless circuit according to claim 1, characterized in that, The bias voltage divider circuit includes: Two voltage divider resistors are connected in series. One end of the two voltage divider resistors is connected to the DC power supply and the power input terminal of the Hall sensor. The other end of the two voltage divider resistors is grounded. The second input terminal of the current processing unit is connected to the connection point between the two voltage divider resistors. A filter capacitor is connected in parallel across the two voltage divider resistors connected in series.

3. The totem pole bridgeless circuit according to claim 1, characterized in that, The totem pole bridgeless circuit also includes: The voltage sampling unit has its input terminal connected to the AC input terminal of the totem pole bridgeless circuit, its first output terminal connected to the control terminal of the first polarity switching switch, and its second output terminal connected to the control terminal of the second polarity switching switch.

4. The totem pole bridgeless circuit according to claim 1, characterized in that, The totem pole bridgeless circuit also includes: The voltage sampling unit has a first input terminal connected to the output terminal of the Hall sensor, a second input terminal connected to the power input terminal of the Hall sensor, a first output terminal connected to the control terminal of the first polarity switching switch, and a second output terminal connected to the control terminal of the second polarity switching switch.

5. The totem pole bridgeless circuit according to claim 1, characterized in that, The totem pole bridgeless circuit also includes: The fast overcurrent protection unit has its input terminal connected to the output terminal of the operational amplifier and its output terminal connected to the input terminal of the controller.

6. The totem pole bridgeless circuit according to claim 1, characterized in that, The control unit further includes: The power factor correction circuit has its input terminal connected to the output terminal of the analog-to-digital converter and its output terminal connected to the controller.

7. A power supply module, characterized in that, include: The totem pole bridgeless circuit as described in any one of claims 1-6.

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