Isolation power supply circuit and isolation power supply

Abstract

The utility model provides an isolation power supply circuit and an isolation power supply with the isolation power supply circuit, the isolation power supply circuit comprises a motor driving module, an isolation transformer and a rectification filtering module which are connected in sequence, under the control of an externally input control signal, the motor driving module generates a first alternating signal, and the first alternating signal is converted into a second alternating signal; the isolation transformer converts the received first alternating signal into a second alternating signal, and finally the rectification filtering module converts the second alternating signal into a direct current signal required by design and outputs the direct current signal. The primary winding of the transformer is directly driven through the motor driving chip, a complex driving control circuit is replaced, the circuit design and layout are simplified, the control complexity and cost of the isolation transformer are reduced, and the integration level of the circuit is improved; and meanwhile, based on the characteristics of the motor driving chip, high-precision control of the isolated power supply is realized, and the isolated power supply can adapt to different loads and environmental conditions and is more universal.

Description

Technical Field

[0001] The utility model relates to the technical field of energy-saving protection of switching power supplies, and particularly relates to an isolated power supply circuit and an isolated power supply with the isolated power supply circuit. Background Art

[0002] An isolated power supply is a power supply system with electrical isolation between the input and the output. It provides electrical isolation between the input circuit and the output circuit through a specific device, cutting off the direct current path between the two, thereby achieving higher insulation and safety.

[0003] In some common isolated power supplies, an isolation transformer is used for electrical isolation between the input circuit and the output circuit. Currently, a relatively common way to drive the isolation transformer is to drive one or more MOS transistors to conduct through a PWM signal to provide a driving voltage to the primary winding of the isolation transformer, so that an alternating voltage is generated in the primary winding of the isolation transformer. The flowing current generates a changing magnetic field, which is transmitted to the secondary winding through the magnetic core, and an alternating voltage is induced in the secondary winding, that is, electrical energy is transmitted from the primary winding to the secondary winding through magnetic field coupling rather than direct electrical connection, thereby achieving electrical isolation.

[0004] However, although using MOS transistors to drive and control the isolation transformer has high efficiency, electrical isolation, low noise, anti-interference, and can be applied to a variety of application scenarios, the design of driving the isolation transformer with MOS transistors is relatively complex and requires considering many factors, such as the waveform, timing, and level matching of the driving signal. In the design, it is often necessary to add some auxiliary circuits such as oscillation circuits and driving ICs, which results in low integration of the entire circuit of the isolated power supply and complex control methods, and is not conducive to the miniaturization of the isolated power supply; at the same time, in the case of unstable or fluctuating power quality, it may also affect the switching performance of the MOS transistors and the stability of the circuit. Summary of the Utility Model

[0005] The utility model provides an isolated power supply circuit and an isolated power supply with the isolated power supply circuit, which can solve the technical problems of low integration, complex control method, and poor stability of the driving control circuit of the existing isolated power supply.

[0006] In a first aspect, an embodiment of the present application provides an isolated power supply circuit, including:

[0007] A motor drive module, configured to generate a first alternating signal in response to a control signal;

[0008] An isolation transformer, including a primary winding and a secondary winding, the primary winding of the isolation transformer is connected to the motor drive module; the isolation transformer is configured to convert the first alternating signal received by its primary winding into a second alternating signal and output it through the secondary winding;

[0009] A rectifying and filtering module is connected to the secondary winding of the isolation transformer; the rectifying and filtering module is used to rectify and filter the received second alternating signal, convert the second alternating signal into a required direct current signal and output it.

[0010] In some embodiments, the isolated power supply circuit further includes a main control module connected to the motor drive module;

[0011] The main control module is used to provide the control signal to the motor drive module; the control signal includes a first signal and a second signal with the same period and opposite polarities, and the frequencies of the first signal and the second signal are greater than or equal to 100 KHz; wherein, the first signal and the second signal are level signals or pulse width modulation signals.

[0012] In some embodiments, the motor drive module includes a motor drive chip.

[0013] In some embodiments, the isolated power supply circuit further includes a power control module connected between the motor drive module and the primary winding of the isolation transformer;

[0014] The motor drive module is further used to generate a power control signal representing different output powers according to the first signal and the second signal; the power control module is used to adjust the power of the first alternating signal according to the power control signal and output it.

[0015] In some embodiments, the power control module includes a first switching tube, a second switching tube, a third switching tube and a fourth switching tube;

[0016] The power control signal at least includes a first power control signal representing a first output power and a second power control signal representing a second output power;

[0017] Wherein, in response to the first power control signal, the power control module controls the first switching tube and the fourth switching tube to conduct, and the second switching tube and the third switching tube to cut off, and adjusts the power of the first alternating signal to the first power; and, in response to the second power control signal, the power control module controls the first switching tube and the fourth switching tube to cut off, and the second switching tube and the third switching tube to conduct, and adjusts the power of the first alternating signal to the second power;

[0018] Alternatively, in response to the first power control signal, the power control module controls the first switch tube and the fourth switch tube to turn off, and the second switch tube and the third switch tube to turn on, so as to adjust the power of the first alternating signal to a first power; and, in response to the second power control signal, the power control module controls the first switch tube and the fourth switch tube to turn on, and the second switch tube and the third switch tube to turn off, so as to adjust the power of the first alternating signal to a second power.

[0019] In some embodiments, the power control module is integrated in the motor drive chip.

[0020] In some embodiments, the isolated power supply circuit further includes a feedback protection module;

[0021] The isolation transformer further includes an auxiliary winding; the feedback protection module is connected between the main control module and the auxiliary winding of the isolation transformer; the feedback protection module is configured to receive a third alternating signal generated across the auxiliary winding, and convert the third alternating signal into a feedback DC signal and transmit it to the main control module;

[0022] The main control module is further configured to stop providing the control signal to the motor drive module when an abnormality occurs in the isolated power supply circuit according to the feedback DC signal; wherein, the occurrence of an abnormality in the isolated power supply circuit includes at least one of short circuit, overcurrent, overvoltage, and overheating.

[0023] In some embodiments, the feedback protection module includes a first resistor, a first diode, a second resistor, a first capacitor, a third resistor, and a second diode;

[0024] A first end of the first resistor is connected to a first end of the auxiliary winding, and a second end of the first resistor is connected to a second end of the auxiliary winding; a first end of the first diode is connected to the first end of the first resistor; a first end of the second resistor is connected to a second end of the first diode; a first end of the first capacitor is connected to a second end of the second resistor, and a second end of the first capacitor is connected to the second end of the first resistor and a preset voltage terminal respectively; a first end of the third resistor is connected to the first end of the second resistor, and a second end of the third resistor is connected to the second end of the first capacitor; a first end of the second diode is connected to an external input power supply, and a second end of the second diode is connected to the first end of the third resistor and the main control module respectively.

[0025] In some embodiments, the rectification and filtering module includes a third diode, a second capacitor, a third capacitor, a buck-boost chip, and a fourth capacitor;

[0026] The first end of the third diode is connected to the first end of the secondary winding; the first end of the second capacitor is connected to the second end of the third diode, and the second end of the second capacitor is respectively connected to the second end of the secondary winding and a preset voltage terminal; the first end of the third capacitor is connected to the first end of the second capacitor, and the second end of the third capacitor is connected to the second end of the second capacitor; the input end of the buck-boost chip is connected to the first end of the third capacitor, and the output end of the buck-boost chip is used to output the required DC signal; the first end of the fourth capacitor is connected to the output end of the buck-boost chip, and the second end of the fourth capacitor is connected to the preset voltage terminal.

[0027] In a second aspect, an embodiment of the present application provides an isolated power supply, which includes a housing and the isolated power supply circuit described in any embodiment of the first aspect above.

[0028] The isolated power supply circuit and the isolated power supply having the isolated power supply circuit provided by the embodiments of the present application, wherein the isolated power supply circuit includes a motor drive module, an isolation transformer, and a rectification and filtering module connected in sequence. Under the control of an externally input control signal, the motor drive module generates a first alternating signal, the isolation transformer converts the received first alternating signal into a second alternating signal, and finally the rectification and filtering module converts the second alternating signal into a DC signal required by the design and outputs it. Compared with the prior art, based on the principle that the motor drive chip can drive the motor coil, the present application applies it to the isolation transformer, that is, directly drives the primary winding of the transformer through the motor drive chip, replacing the complex drive control circuit, simplifying the circuit design and layout, reducing the control complexity and cost of the isolation transformer, and improving the circuit integration; at the same time, based on the high-precision control ability, high-efficiency power conversion ability, stable performance, and reliable working characteristics of the motor drive chip, high-precision control of the isolated power supply is achieved, and it can adapt to different loads and environmental conditions, making it more universal. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings here are incorporated into the specification and form a part of the specification, showing embodiments in line with the present application, and are used together with the specification to explain the principles of the present application.

[0030] Figure 1 It is a schematic structural diagram of an isolated power supply circuit provided by an embodiment of the present application;

[0031] Figure 2 It is a schematic structural diagram of an isolated power supply circuit provided by another embodiment of the present application;

[0032] Figure 3 It is a schematic structural diagram of an isolated power supply circuit provided by yet another embodiment of the present application;

[0033] Figure 4 Schematic diagram of an isolated power supply circuit provided by another embodiment of the present application;

[0034] Figure 5 Circuit diagram of an isolated power supply circuit provided by an embodiment of the present application;

[0035] Figure 6 Circuit diagram of an isolated power supply circuit provided by another embodiment of the present application;

[0036] Figure 7 Schematic diagram of an isolated power supply provided by an embodiment of the present application.

[0037] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed Description of the Embodiments

[0038] The present utility model will be further described in detail below in conjunction with the drawings through specific embodiments. Similar elements in different embodiments are labeled with related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification, in order to avoid the core part of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and the general technical knowledge in the art.

[0039] In addition, the features, operations, or characteristics described in the specification can be combined in any appropriate manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for clearly describing a certain embodiment, and do not mean that they are the necessary sequences, unless it is stated that a certain sequence must be followed.

[0040] The terms "first", "second", etc. in the description and claims of this application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of this application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same category, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the description and claims means at least one of the connected objects, and the character " / ", generally represents an "or" relationship between the associated objects before and after. And the "connection" and "coupling" mentioned in this application, unless otherwise specified, both include direct and indirect connection (coupling).

[0041] The technical solution of this application and how the technical solution of this application solves the above technical problems will be described in detail below with specific embodiments. These several specific embodiments below can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0042] Figure 1 The following is a schematic structural diagram of an isolated power supply circuit provided by an embodiment of this application. As Figure 1 shown, the isolated power supply circuit provided by this embodiment includes a motor drive module 110, an isolation transformer 120, and a rectification and filtering module 130 connected in sequence.

[0043] In this embodiment, the input end of the motor drive module 110 is used to receive a control signal input from the outside. The motor drive module 110 responds to the control signal, generates a first alternating signal and transmits it to the isolation transformer 120. The isolation transformer 120 includes a primary winding and a secondary winding. The primary winding of the isolation transformer 120 is connected to the motor drive module 110. After receiving the first alternating signal output by the motor drive module 110, the primary winding of the isolation transformer 120 converts the first alternating signal into a second alternating signal at its secondary winding and then outputs it. The rectification and filtering module 130 is connected to the secondary winding of the isolation transformer 120. The rectification and filtering module 130 is used to rectify and filter the received second alternating signal, convert the second alternating signal into a DC signal required by the load connected to the isolated power supply and output it.

[0044] In some embodiments, the motor drive module 110 includes a motor drive chip.

[0045] It can be understood that in a common DC motor or AC motor, there is a fixed permanent magnet or electromagnet inside as the stator, and a rotatable armature (rotor with coils) as the mover. When current passes through the armature coil, a magnetic field is generated, and this magnetic field interacts with the stator magnetic field to generate an electromagnetic force, thereby driving the motor to rotate. After the motor is powered on, according to the externally input control signal, the motor drive circuit generates a corresponding drive signal, which acts on the rotor with coils in the motor to control the motor to operate at a preset speed and rotation type.

[0046] As a key component for controlling and driving motors, the motor drive chip has high - efficiency power conversion capabilities, can minimize power loss, improve the efficiency of the drive control circuit, and also helps reduce energy consumption and improve the overall operating efficiency of the device. The motor drive chip integrates multiple functional modules, including power management, current detection, speed control, etc., realizing the integration of multiple control methods. The high integration not only simplifies the circuit design and layout, but also reduces the use of external components, lowering the complexity and cost of the drive control circuit.

[0047] In the embodiment of the present application, based on the principle that the motor drive chip can drive the motor coil, it is applied to the isolation transformer 120, that is, the motor drive chip directly drives the primary winding of the transformer, replacing the complex drive control circuit in the isolated power supply, realizing the simplification of the circuit design and layout, and reducing the circuit complexity and cost. Most importantly, the motor drive chip can achieve precise control of the motor phase sequence and pulse signal, realizing high - precision positioning control, while also reducing the control complexity of the isolation transformer 120 and improving the circuit integration.

[0048] Figure 2 This is a schematic structural diagram of the isolated power supply circuit provided by another embodiment of the present application. As Figure 2 shown, on the basis of any of the above - mentioned embodiments, the isolated power supply circuit provided in this embodiment further includes a main control module 140 connected to the motor drive module 110.

[0049] In this embodiment, the main control module 140 is used to provide a control signal to the motor drive module 110, where the control signal includes a first signal and a second signal with the same period and opposite polarities. Among them, the first signal and the second signal are level signals (high - low level signals) or pulse - width modulation signals (PWM signals).

[0050] It can be understood that the main control module 140, as a control signal source, can be a microcontroller, a single-chip microcomputer, a sensor, etc. It generates a first signal and a second signal with the same period and opposite polarities according to the setting, and transmits them to the motor drive module 110. After receiving the first signal and the second signal with the same period and opposite polarities, the motor drive module 110 transmits them to the primary winding of the isolation transformer 120 to generate an alternating voltage.

[0051] In some embodiments, the first signal and the second signal are greater than or equal to 100 KHz to ensure that they can generate sufficient alternating signals for the voltage at the primary winding of the isolation transformer 120.

[0052] In some embodiments, the motor drive module 110 is further configured to generate a power control signal representing different output powers according to the first signal and the second signal. It can be understood that the motor drive chip in the motor drive module 110 includes a signal processing module inside, which can identify and convert the received control signal to generate the current or voltage signal required to drive the primary winding of the isolation transformer 120. The motor drive chip can also adjust the magnitude of the output current to adapt to the primary windings of isolation transformers 120 with different powers and different working loads. By adjusting the duty cycles of the first signal and the second signal (in PWM control), precise control of the current or voltage required for the primary winding of the isolation transformer 120 can be achieved.

[0053] Figure 3 The structural schematic diagram of the isolated power supply circuit provided by another embodiment of the present application is as follows. As Figure 3 shown, based on any of the above embodiments, the isolated power supply circuit provided in this embodiment may further include a power control module 150 connected between the motor drive module 110 and the primary winding of the isolation transformer 120.

[0054] In this embodiment, the power control module 150 is configured to adjust the power of the first alternating signal and output it according to the power control signal representing different output powers output by the motor drive module 110, so as to achieve precise control of the current or voltage required for the primary winding of the isolation transformer 120.

[0055] In some embodiments, the power control signal at least includes a first power control signal representing a first output power and a second power control signal representing a second output power.

[0056] In some embodiments, the power control module 150 includes an H-bridge circuit composed of a first switching transistor Q1, a second switching transistor Q2, a third switching transistor Q3, and a fourth switching transistor Q4. By controlling the on / off states of the four switching transistors, the flow direction of the current in the primary winding is changed, and according to the received power control signal representing different output powers, the magnitudes of the drive signals for controlling the four switching transistors are adjusted to regulate the output current or voltage.

[0057] Specifically, in response to the first power control signal, the power control module 150 controls the first switching transistor Q1 and the fourth switching transistor Q4 to conduct, and the second switching transistor Q2 and the third switching transistor Q3 to cut off, and adjusts the power of the first alternating signal to the first power; and, in response to the second power control signal, the power control module 150 controls the first switching transistor Q1 and the fourth switching transistor Q4 to cut off, and the second switching transistor Q2 and the third switching transistor Q3 to conduct, and adjusts the power of the first alternating signal to the second power;

[0058] Alternatively, conversely, in response to the first power control signal, the power control module 150 controls the first switching transistor Q1 and the fourth switching transistor Q4 to cut off, and the second switching transistor Q2 and the third switching transistor Q3 to conduct, and adjusts the power of the first alternating signal to the first power; and, in response to the second power control signal, the power control module 150 controls the first switching transistor Q1 and the fourth switching transistor Q4 to conduct, and the second switching transistor Q2 and the third switching transistor Q3 to cut off, and adjusts the power of the first alternating signal to the second power.

[0059] In some embodiments, the power control module 150 is integrated in the motor drive chip. For some motor drive chips with complete functions, multiple functional modules are integrated, including control modules such as power management, current detection, speed control, and power control.

[0060] For example, a motor drive chip of model TC118S with single-channel DC forward and reverse rotation integrates a power MOS full-bridge drive unit, which can achieve the control of adjusting the power of the first alternating signal output by the power control module 150 in the above embodiments. The design is simple, reducing the need for peripheral components and lowering the system complexity.

[0061] For another example, a dual-motor driver chip with the model number DRV8701ERGER developed by Texas Instruments is mainly used to drive N-channel power MOSFETs to achieve precise control of DC motors (such as brushed DC motors and brushless DC motors). It has two independent channels and can precisely control the speed and direction of the motor through PWM (pulse width modulation) input signals, realizing the smooth operation and precise control of the motor. If this motor driver chip is used as the core for driving the isolation transformer 120 in the isolated power supply of this application, in order to achieve precise control of the current or voltage at the primary winding of the isolation voltage transformer, it is necessary to externally connect the power control module 150 described in the above embodiments to achieve this.

[0062] It can be understood that the two motor driver chips have their respective functions and characteristics, and need to be selected according to the design requirements of the isolated power supply in actual applications. Correspondingly, different power control modules 150 are selected to meet the design requirements.

[0063] Figure 4 FIG. [X] is a schematic structural diagram of an isolated power supply circuit provided by another embodiment of this application. As Figure 4 shown, on the basis of any of the above embodiments, the isolated power supply circuit provided in this embodiment further includes a feedback protection module 160.

[0064] In this embodiment, in addition to the primary winding and the secondary winding, the isolation transformer 120 further includes an auxiliary winding disposed on one side of the primary winding. The feedback protection module 160 is connected between the main control module 140 and the auxiliary winding of the isolation transformer 120. The feedback protection module 160 is used to receive the third alternating signal generated at both ends of the auxiliary winding and convert the third alternating signal into a feedback DC signal and transmit it to the main control module 140. The main control module 140 is further used to stop providing a control signal to the motor drive module 110 when an abnormality occurs in the isolated power supply circuit according to the feedback DC signal; wherein, an abnormality in the isolated power supply circuit includes at least one of short circuit, overcurrent, overvoltage, and overheating, so as to protect the isolated power supply circuit and subsequent load devices from being damaged, and improve the reliability and safety of the isolated power supply circuit.

[0065] Figure 5 FIG. [X] is a circuit diagram of an isolated power supply circuit provided by an embodiment of this application. As Figure 5 shown, in this embodiment, the isolated power supply circuit includes a motor drive module 110, an isolation transformer 120, and a rectification and filtering module 130 connected in sequence, as well as a main control module 140 and a feedback protection module 160.

[0066] In this embodiment, the motor drive module 110 includes a motor drive chip U1. The motor drive chip U2 is a motor drive chip with the model TC118S, which internally integrates a power MOS full-bridge drive unit and can serve as the power control module 150. The main control module 140 includes a single-chip microcomputer U3, which is mainly used to provide a first signal (PWMA) and a second signal (PWMB) with the same period and opposite polarities to the motor drive chip U1. The signals are output by the motor drive chip U1 and applied to the primary winding of the isolation transformer 120, thereby generating a second alternating signal on its secondary winding.

[0067] In this embodiment, the feedback protection module 160 includes a first resistor R1, a first diode D1, a second resistor R2, a first capacitor C1, a third resistor R3, and a second diode D2. Specifically, the first end of the first resistor R1 is connected to the first end of the auxiliary winding, and the second end of the first resistor R1 is connected to the second end of the auxiliary winding; the first end of the first diode D1 is connected to the first end of the first resistor R1; the first end of the second resistor R2 is connected to the second end of the first diode D1; the first end of the first capacitor C1 is connected to the second end of the second resistor R2, and the second end of the first capacitor C1 is respectively connected to the second end of the first resistor R1 and the first preset voltage terminal (GND1); the first end of the third resistor R3 is connected to the first end of the second resistor R2, and the second end of the third resistor R3 is connected to the second end of the first capacitor C1; the first end of the second diode D2 is connected to an external input power supply VDD, and the second end of the second diode D2 is connected to the first end of the third resistor R3 and the feedback pin of the main control module respectively.

[0068] In this embodiment, the rectification and filtering module includes a third diode D3, a second capacitor C2, a third capacitor C3, a buck-boost chip U2, and a fourth capacitor C4. Specifically, the first end of the third diode D3 is connected to the first end of the secondary winding; the first end of the second capacitor C2 is connected to the second end of the third diode D3, and the second end of the second capacitor C2 is respectively connected to the second end of the secondary winding and the second preset voltage terminal (GND2); the first end of the third capacitor C3 is connected to the first end of the second capacitor C2, and the second end of the third capacitor C3 is connected to the second end of the second capacitor C2; the input end of the buck-boost chip U2 is connected to the first end of the third capacitor C3, the output end of the buck-boost chip U2 is used to output the required DC signal, and the grounding end of the buck-boost chip U2 is connected to the second preset voltage terminal (GND2); the first end of the fourth capacitor C4 is connected to the output end of the buck-boost chip U2, and the second end of the fourth capacitor C4 is connected to the second preset voltage terminal (GND2).

[0069] Figure 6 It is the circuit diagram of the isolated power supply circuit provided by another embodiment of this application. As Figure 6As shown in the figure, in this embodiment, the isolated power supply circuit includes a motor drive module 110, an isolation transformer 120, and a rectification and filtering module 130 that are connected in sequence, as well as a main control module 140, a power control module 150, and a feedback protection module 160.

[0070] In this embodiment, the motor drive chip U1 uses a dual-motor driver chip with the model DRV8701ERGER, which requires an external power control module 150 to control the current or voltage on the isolation voltage transformer.

[0071] The first switch tube Q1, the second switch tube Q2, the third switch tube Q3, and the fourth switch tube Q4 in the power control module 150 are respectively connected to the gate drive output end of the motor drive chip U1. According to the first power control signal representing the first output power and the second power control signal representing the second output power output by the motor drive chip U1, the on-off states of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, and the fourth switch tube Q4 are controlled. While changing the flowing direction of the current in the primary winding, the current or voltage output by the four switch tubes is also adjusted to achieve the magnitude of the first alternating signal acting on both ends of the primary winding.

[0072] In summary, the isolated power supply circuit provided by the embodiment of the present application directly drives the primary winding of the transformer through the motor drive chip, replaces the complex drive control circuit, simplifies the circuit design and layout, reduces the control complexity and cost of the isolation transformer, and improves the circuit integration; at the same time, based on the high-precision control ability, efficient power conversion ability, stable performance, and reliable working characteristics of the motor drive chip, high-precision control of the isolated power supply is achieved, and it can adapt to different loads and environmental conditions, making it more universal.

[0073] Figure 7 This is a schematic structural diagram of an isolated power supply provided by an embodiment of the present application. As Figure 7 shown, the isolated power supply provided by this embodiment includes a housing 210 and the isolated power supply circuit 220 described in any of the above embodiments. The isolated power supply circuit 220 has the beneficial effects of the isolated power supply circuit in any of the above embodiments, which will not be elaborated here.

[0074] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art, without departing from the purpose of the present application and the scope protected by the claims, can make several simple deductions, deformations, or substitutions according to the idea of the present application, which all fall within the protection scope of the present application.

Claims

1. An isolated power supply circuit, characterized in that, Comprising: A motor drive module, configured to generate a first alternating signal in response to a control signal; An isolation transformer, including a primary winding and a secondary winding, wherein the primary winding of the isolation transformer is connected to the motor drive module; the isolation transformer is configured to convert the first alternating signal received by its primary winding into a second alternating signal and output the second alternating signal through the secondary winding; A rectification and filtering module, connected to the secondary winding of the isolation transformer; the rectification and filtering module is configured to rectify and filter the received second alternating signal, and convert the second alternating signal into a required DC signal and output the DC signal.

2. The isolated power supply circuit according to claim 1, wherein, Further comprising a main control module connected to the motor drive module; The main control module is configured to provide the control signal to the motor drive module; the control signal includes a first signal and a second signal with the same period and opposite polarities, and the frequencies of the first signal and the second signal are greater than or equal to 100 KHz; wherein, the first signal and the second signal are level signals or pulse width modulation signals.

3. The isolated power supply circuit according to claim 2, wherein The motor drive module includes a motor drive chip.

4. The isolated power supply circuit according to claim 3, wherein Further comprising a power control module connected between the motor drive module and the primary winding of the isolation transformer; The motor drive module is further configured to generate a power control signal representing different output powers according to the first signal and the second signal; the power control module is configured to adjust the power of the first alternating signal according to the power control signal and output the adjusted signal.

5. The isolated power supply circuit according to claim 4, wherein The power control module includes a first switching tube, a second switching tube, a third switching tube and a fourth switching tube; The power control signal at least includes a first power control signal representing a first output power and a second power control signal representing a second output power; Wherein, in response to the first power control signal, the power control module controls the first switching tube and the fourth switching tube to conduct, and the second switching tube and the third switching tube to cut off, so as to adjust the power of the first alternating signal to a first power; and, in response to the second power control signal, the power control module controls the first switching tube and the fourth switching tube to cut off, and the second switching tube and the third switching tube to conduct, so as to adjust the power of the first alternating signal to a second power; Alternatively, in response to the first power control signal, the power control module controls the first switching tube and the fourth switching tube to cut off, and the second switching tube and the third switching tube to conduct, so as to adjust the power of the first alternating signal to a first power; and, in response to the second power control signal, the power control module controls the first switching tube and the fourth switching tube to conduct, and the second switching tube and the third switching tube to cut off, so as to adjust the power of the first alternating signal to a second power.

6. The isolated power supply circuit according to claim 4, wherein The power control module is integrated in the motor drive chip.

7. The isolated power supply circuit according to claim 2, wherein, Further comprising a feedback protection module; The isolation transformer further includes an auxiliary winding; the feedback protection module is connected between the main control module and the auxiliary winding of the isolation transformer; the feedback protection module is configured to receive a third alternating signal generated at both ends of the auxiliary winding, and convert the third alternating signal into a feedback DC signal and transmit the feedback DC signal to the main control module; The main control module is further configured to stop providing the control signal to the motor drive module when an abnormality occurs in the isolated power supply circuit according to the feedback DC signal; wherein, the occurrence of an abnormality in the isolated power supply circuit includes at least one of short circuit, overcurrent, overvoltage, and overheating.

8. The isolated power supply circuit according to claim 7, characterized in that, The feedback protection module includes a first resistor, a first diode, a second resistor, a first capacitor, a third resistor, and a second diode; The first end of the first resistor is connected to the first end of the auxiliary winding, and the second end of the first resistor is connected to the second end of the auxiliary winding; the first end of the first diode is connected to the first end of the first resistor; the first end of the second resistor is connected to the second end of the first diode; the first end of the first capacitor is connected to the second end of the second resistor, and the second end of the first capacitor is connected to the second end of the first resistor and the preset voltage terminal respectively; the first end of the third resistor is connected to the first end of the second resistor, and the second end of the third resistor is connected to the second end of the first capacitor; the first end of the second diode is connected to an external input power supply, and the second end of the second diode is connected to the first end of the third resistor and the main control module respectively.

9. The isolated power supply circuit according to claim 1, wherein The rectification and filtering module includes a third diode, a second capacitor, a third capacitor, a buck-boost chip, and a fourth capacitor; The first end of the third diode is connected to the first end of the secondary winding; the first end of the second capacitor is connected to the second end of the third diode, and the second end of the second capacitor is connected to the second end of the secondary winding and the preset voltage terminal respectively; the first end of the third capacitor is connected to the first end of the second capacitor, and the second end of the third capacitor is connected to the second end of the second capacitor; the input terminal of the buck-boost chip is connected to the first end of the third capacitor, and the output terminal of the buck-boost chip is used to output the required DC signal; the first end of the fourth capacitor is connected to the output terminal of the buck-boost chip, and the second end of the fourth capacitor is connected to the preset voltage terminal.

10. An isolated power supply, characterized in that, It includes a housing and the isolated power supply circuit according to any one of claims 1-9.

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