Power supply circuit and servo driver equipment

Abstract

The invention discloses a power supply circuit and servo driver equipment, the power supply circuit comprises a rectifier bridge, an inverter circuit, a bus capacitor, an inductor, a first switch, a switch adjusting circuit and a control module, the first end of the first switch is connected between the inductor and the positive electrode of the bus capacitor, and the second end of the first switch is connected between the inductor and the positive electrode of the bus capacitor; the second end of the first switch is connected between the second output end of the rectifier bridge and the negative electrode of the bus capacitor; the switch adjusting circuit is arranged between the bus capacitor and the inverter circuit. The first switch and the switch adjusting circuit are arranged between the rectifier bridge and the inverter circuit, the voltage input to the inverter circuit by the rectifier bridge is controlled through the first switch and the switch adjusting circuit, and at the moment, the power supply circuit can drive motors of different grades under the AC220V input voltage. Different levels of servo drivers do not need to be designed for motors with different voltage levels, so that the servo drivers with the same power and different voltage levels are matched with the motors, and the research and development cost of the servo drivers is reduced.

Description

Technical Field

[0001] The present application relates to the field of motor technology, and in particular to a power supply circuit and a servo drive device. Background Art

[0002] The power supply scheme of industrial servo drives usually consists of the grid input, rectifier bridge and bus capacitor. Since most industrial equipment is powered by single-phase AC220V, an external AC380V power supply is required when using an AC380V motor. Furthermore, when using an AC380V motor, an AC380V servo drive is required. When the servo drive is working normally, the large bus capacitor is constantly charged and discharged, generating a certain amount of voltage ripple. When the servo motor load increases, the voltage ripple of the bus will also increase, which not only reduces the service life of the bus capacitor and power devices, but may also cause false alarms in the servo drive and even damage the power devices.

[0003] Therefore, existing servo drives are usually designed with two voltage levels and use large electrolytic capacitors as bus capacitors. However, this design not only increases the R&D cost and volume of the servo drive, but also makes servo drives and servo motors of the same power but different voltage levels incompatible, which reduces the convenience of user use. Summary of the invention

[0004] The present application mainly provides a power supply circuit and a servo drive device to solve the problems of high R&D cost and volume of the servo drive and low user convenience.

[0005] The present application provides a power supply circuit, comprising:

[0006] A rectifier bridge, wherein an input end of the rectifier bridge receives mains power and outputs a first voltage based on rectification of the mains power;

[0007] An inverter circuit, wherein a first input end of the inverter circuit is connected to a first output end of the rectifier bridge, a second input end of the inverter circuit is connected to a second output end of the rectifier bridge, and an output end of the inverter circuit is connected to a motor;

[0008] A bus capacitor, wherein the positive electrode of the bus capacitor is connected between the first input end of the inverter circuit and the first output end of the rectifier bridge, and the negative electrode of the bus capacitor is connected between the second input end of the inverter circuit and the second output end of the rectifier bridge, and the bus capacitor is used to filter and output a second voltage;

[0009] an inductor, one end of which is connected to the first output end of the rectifier bridge, and the other end of which is connected to the positive electrode of the bus capacitor;

[0010] A first switch, wherein a first end of the first switch is connected between the inductor and the positive electrode of the bus capacitor, and a second end of the first switch is connected between the second output end of the rectifier bridge and the negative electrode of the bus capacitor;

[0011] A switch regulating circuit, disposed between the bus capacitor and the inverter circuit, and used to cooperate with the first switch to control the input voltage of the motor;

[0012] A control module is respectively connected to the motor, the first switch and the switch regulation circuit, and is used to obtain the first voltage and the second voltage, identify the parameters of the motor, and determine the third voltage based on the parameters of the motor; the control module is used to control the input voltage of the motor through the first switch and the switch regulation circuit based on the third voltage, the first voltage and the second voltage.

[0013] The switch regulation circuit includes a second switch and a regulation circuit, the first end of the second switch is connected to the first end of the regulation circuit, the second end of the regulation circuit is connected between the first input end of the inverter circuit and the positive electrode of the bus capacitor, and the second end of the second switch is connected between the second input end of the inverter circuit and the negative electrode of the bus capacitor.

[0014] Among them, the power supply circuit also includes a first drive circuit and a second drive circuit, the first drive circuit is respectively connected to the control module and the first switch, and is used to control the first switch to be turned on or off; the second drive circuit is respectively connected to the control module and the second switch, and is used to control the second switch to be turned on or off.

[0015] Wherein, the control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor;

[0016] The control module is used for controlling the first switch to be disconnected through the first drive circuit when the third voltage is lower than the second voltage, and controlling the second switch to be connected through the second drive circuit.

[0017] Wherein, the control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor;

[0018] The control module is used for controlling the first switch to be disconnected through the first drive circuit and controlling the second switch to be disconnected through the second drive circuit when the third voltage is greater than the second voltage and the third voltage is less than the first voltage.

[0019] Wherein, the control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor;

[0020] The control module is used to control the first switch to be turned on and then turned off at a preset switching frequency through the first drive circuit when the third voltage is greater than the second voltage and the third voltage is greater than or equal to the first voltage, and to control the second switch to be turned off through the second drive circuit.

[0021] The regulating circuit includes a first diode and a first resistor, the anode of the first diode is connected to the first end of the second switch, the cathode of the first diode is connected between the first input end of the inverter circuit and the anode of the bus capacitor, one end of the first resistor is connected between the anode of the first diode and the first end of the second switch, and the other end of the first resistor is connected between the first diode and the anode of the bus capacitor.

[0022] The power supply circuit further includes a second diode, an anode of the second diode is connected to the first end of the first switch, and a cathode of the second diode is connected to the positive electrode of the bus capacitor.

[0023] Among them, the first end of the first drive circuit is connected to the first end of the first switch, the second end of the first drive circuit is connected to the second end of the first switch, and the third end of the drive circuit is connected to the first end of the control module; the first end of the second drive circuit is connected to the first end of the second switch, the second end of the second drive circuit is connected to the second end of the second switch, and the third end of the second drive circuit is connected to the second end of the control module.

[0024] The present application also provides a servo drive device, including a motor, an encoder and a power supply circuit as described above.

[0025] The beneficial effects of the present application are as follows: the present application sets a first switch and a switch regulation circuit between the rectifier bridge and the inverter circuit, and the control module controls the voltage input from the rectifier bridge to the inverter circuit through the first switch and the switch regulation circuit, thereby controlling the input voltage of the motor. At this time, the power supply circuit can drive the AC220V motor and the AC380V motor under the AC220V input voltage, that is, drive motors of two voltage levels, and there is no need to design servo drivers of different levels for motors of different voltage levels, so that servo drivers and motors of the same power but different voltage levels can be adapted to each other, thereby reducing the research and development cost of the servo driver and improving the user's convenience; and through the setting of the first switch and the switch regulation circuit, when using a bus capacitor with a smaller capacity, the voltage ripple of the bus is reduced, the volume of the bus capacitor is reduced, and then the volume of the servo driver is reduced, thereby protecting the power device and extending the service life of the bus capacitor, and reducing the probability of false alarm of the servo driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0027] Figure 1 This is a circuit architecture example diagram of a power supply circuit provided in this application;

[0028] Figure 2 This is a waveform diagram of an embodiment of the first voltage, the second voltage, the third voltage, the first switch and the second switch in the working state provided by the present application. DETAILED DESCRIPTION

[0029] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0031] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0034] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0035] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0036] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be connected between, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0037] Existing servo drives are usually designed with two voltage levels and use large electrolytic capacitors as bus capacitors. However, this design not only increases the R&D cost and volume of the servo drive, but also makes servo drives and servo motors of the same power but different voltage levels incompatible, which reduces the convenience of user use.

[0038] This application provides a power supply circuit, see Figure 1-Figure 2 As shown, Figure 1 This is a circuit architecture example diagram of a power supply circuit provided in this application; Figure 2 The power supply circuit 10 of this embodiment includes a rectifier bridge 11, an inverter circuit 12, a bus capacitor 13, an inductor L, a first switch S1, a switch adjustment circuit 14 and a control module 15.

[0039] The input end of the rectifier bridge 11 receives the mains current, that is, the input end of the rectifier bridge 11 is connected to the mains. The main function of the rectifier bridge 11 is to convert alternating current into direct current, that is, the rectifier bridge 11 is used to convert the mains into direct current.

[0040] In some embodiments, the input end of the rectifier bridge 11 receives three-phase electricity, the rectifier bridge 11 rectifies the three-phase electricity, and outputs a first voltage U1. The first voltage U1 is a DC voltage, and the first voltage U1 is also called an input voltage. For example, the input end of the rectifier bridge 11 receives three-phase AC380V or AC220V. In other embodiments, the input end of the rectifier bridge 11 receives single-phase electricity or three-phase electricity with a missing phase.

[0041] The first input terminal 121 of the inverter circuit 12 is connected to the first output terminal 111 of the rectifier bridge 11 , the second input terminal 122 of the inverter circuit 12 is connected to the second output terminal 112 of the rectifier bridge 11 , and the output terminal of the inverter circuit 12 is connected to the motor 16 .

[0042] Optionally, the first output terminal 111 of the rectifier bridge 11 refers to the positive output terminal of the rectifier bridge 11, and the second output terminal 112 of the rectifier bridge 11 refers to the negative output terminal of the rectifier bridge 11; the first input terminal 121 of the inverter circuit 12 refers to the positive input terminal of the inverter circuit 12, and the second input terminal 122 of the inverter circuit 12 refers to the negative input terminal of the inverter circuit 12.

[0043] The inverter circuit 12 refers to a power conversion circuit that converts DC power into AC power. In some embodiments, the inverter circuit 12 receives the first voltage U1 rectified and output by the rectifier bridge 11, and converts it into AC power and outputs it to the motor 16. The voltage output by the inverter circuit 12 is used as the input voltage of the motor 16, also called the power supply voltage, which can drive the motor 16 to work.

[0044] The positive electrode of the bus capacitor 13 is connected between the first input terminal 121 of the inverter circuit 12 and the first output terminal 111 of the rectifier bridge 11, and the negative electrode of the bus capacitor 13 is connected between the second input terminal 122 of the inverter circuit 12 and the second output terminal 112 of the rectifier bridge 11. The bus capacitor 13 is used to filter and output the second voltage U2.

[0045] The bus capacitor 13 is located between the rectifier bridge 11 and the inverter circuit 12, the positive electrode of the bus capacitor 13 is connected between the positive output end of the rectifier bridge 11 and the positive input end of the inverter circuit 12, and the negative electrode of the bus capacitor 13 is connected between the negative output end of the rectifier bridge 11 and the negative input end of the inverter circuit 12.

[0046] The bus capacitor 13 refers to a high capacitance capacitor used for DC power filtering. Optionally, the bus capacitor 13 is used to filter the current output by the rectifier bridge 11 and output the second voltage U2 to the inverter circuit 12. The second voltage U2 is also called the bus voltage.

[0047] Optionally, the inverter circuit 12 receives the first voltage U1 rectified and output by the rectifier bridge 11 and / or the second voltage U2 filtered and output by the bus capacitor 13 , and converts them into alternating current and outputs them to the motor 16 .

[0048] One end of the inductor L is connected to the first output terminal 111 of the rectifier bridge 11 , and the other end of the inductor L is connected to the positive electrode of the bus capacitor 13 .

[0049] The inductor L is also called an inductor, and is a component that can convert electrical energy into magnetic energy and store it. Optionally, the inductor L is used to receive the first voltage U1 output by the first output terminal 111 of the rectifier bridge 11 for filtering and energy storage.

[0050] A first end of the first switch S1 is connected between the inductor L and the positive electrode of the bus capacitor 13 , and a second end of the first switch S1 is connected between the second output end 112 of the rectifier bridge 11 and the negative electrode of the bus capacitor 13 .

[0051] In some embodiments, the first switch S1 is located between the inductor L and the bus capacitor 13 , and is used to adjust or control the current from the rectifier bridge 11 and / or the inductor L to the bus capacitor 13 and the inverter circuit 12 .

[0052] The switch regulation circuit 14 is disposed between the bus capacitor 13 and the inverter circuit 12 , and is used to cooperate with the first switch S1 to control the input voltage of the motor 16 .

[0053] The input voltage of the motor 16 refers to the voltage supplied to the motor 16 , that is, the voltage required to drive the motor 16 ; motors 16 of different voltage levels correspond to different input voltages, that is, the voltages required to drive motors 16 of different voltage levels are different.

[0054] The switch regulation circuit 14 refers to a circuit in a power electronic device for controlling and adjusting output voltage or current. Optionally, the switch regulation circuit 14 uses one or more switches to regulate energy transmission, thereby achieving precise control of the output voltage or current.

[0055] Optionally, the switch regulation circuit 14 is disposed between the bus capacitor 13 and the inverter circuit 12 , and the switch regulation circuit 14 controls the voltage or current input to the inverter circuit 12 , thereby controlling the input voltage of the motor 16 .

[0056] The control module 15 is connected to the motor 16, the first switch S1 and the switch regulation circuit 14 respectively. The control module 15 is used to obtain the first voltage U1 and the second voltage U2, identify the parameters of the motor 16, and determine the third voltage U3 based on the parameters of the motor 16; the control module 15 controls the input voltage of the motor 16 through the first switch S1 and the switch regulation circuit 14 based on the third voltage U3, the first voltage U1 and the second voltage U2.

[0057] The control module 15 refers to a component responsible for the control logic and operation processing of the entire circuit in the power supply circuit 10. The control module 15 includes but is not limited to a microcontroller unit (MCU), a field programmable gate array (FPGA), a digital signal processor (DSP), and a programmable logic device (PLD).

[0058] Optionally, the control module 15 includes a motor parameter self-identification unit (not shown), an input voltage sampling unit (not shown), a bus voltage sampling unit (not shown), a first judgment processing module (not shown) and a second judgment processing module (not shown).

[0059] Optionally, the control module 15 identifies the parameters of the motor 16, such as the voltage level of the motor 16, through the motor parameter self-identification unit; the control module 15 obtains the first voltage U1 by real-time sampling through the input voltage sampling unit, for example, the input voltage sampling unit is connected to the first output terminal 111 of the rectifier bridge 11, and the input voltage sampling unit can sample the first voltage U1; the control module 15 obtains the second voltage U2 by real-time sampling through the bus voltage sampling unit, for example, the bus voltage sampling unit is connected to the positive electrode of the bus capacitor 13, and the bus voltage sampling unit can sample the second voltage U2.

[0060] The third voltage U3 refers to a reference voltage obtained according to the parameters of the motor 16. The reference voltage can ensure that the motor 16 operates at a safe voltage to avoid performance degradation or damage to the motor 16 due to excessively high or low voltage. Optionally, the parameter of the motor 16 is the voltage level of the motor 16, such as AC220V, and the third voltage U3 obtained according to the parameters of the motor 16 is DC312V.

[0061] In other embodiments, the voltage level of the motor 16 is AC380V, and the obtained third voltage U3 is DC600V.

[0062] In some embodiments, the input voltage level is AC220V, and the parameters of motor 16 are AC380V. At this time, the input voltage level does not match the parameters of motor 16, and it is necessary to control the input voltage of motor 16 by adjusting the input voltage, such as boosting, to ensure that motor 16 can operate stably.

[0063] In some embodiments, the control module 15 uses the acquired third voltage U3, the first voltage U1, and the second voltage U2 as inputs, and dynamically adjusts the working state of the first switch S1 and the switch regulation circuit 14 through the built-in control algorithm, controls the input voltage of the inverter circuit 12, and further controls the input voltage of the motor 16. At this time, the control module 15 can accurately control the input voltage of the motor 16 through the first switch S1 and the switch regulation circuit 14, and when the input voltage level is AC220V, it ensures that the motor 16 of two voltage levels of AC220V and AC380V can be driven to run stably.

[0064] Optionally, the control module 15 performs judgment processing on the third voltage U3 , the first voltage U1 , and the second voltage U2 through the first judgment processing module and the second judgment processing module to adjust the working states of the first switch S1 and the switch regulation circuit 14 .

[0065] In this embodiment, a first switch S1 and a switch regulating circuit 14 are arranged between the rectifier bridge 11 and the inverter circuit 12. The control module 15 controls the voltage input from the rectifier bridge 11 to the inverter circuit 12 through the first switch S1 and the switch regulating circuit 14, thereby controlling the input voltage of the motor 16. At this time, the power supply circuit 10 can drive the AC220V motor 16 and the AC380V motor 16 under the AC220V input voltage, that is, drive motors 16 of two voltage levels. There is no need to design servo drivers of different levels for motors 16 of different voltage levels, so that servo drivers and motors 16 of the same power but different voltage levels can be adapted to each other, thereby reducing the R&D cost of the servo driver and improving the convenience of use for users. Moreover, by the arrangement of the first switch S1 and the switch regulating circuit 14, when a bus capacitor 13 with a smaller capacity is used, the voltage ripple of the bus is reduced, the volume of the bus capacitor 13 is reduced, and the volume of the servo driver is reduced, thereby protecting the power device and extending the service life of the bus capacitor 13, thereby reducing the probability of false alarm of the servo driver.

[0066] According to some embodiments of the present application, Figure 1 As shown, the switch regulation circuit 14 of this embodiment includes a second switch S2 and a regulation circuit 141, the first end of the second switch S2 is connected to the first end of the regulation circuit 141, the second end of the regulation circuit 141 is connected between the first input terminal 121 of the inverter circuit 12 and the positive electrode of the bus capacitor 13, and the second end of the second switch S2 is connected between the second input terminal 122 of the inverter circuit 12 and the negative electrode of the bus capacitor 13.

[0067] In some embodiments, the second switch S2 and the regulation circuit 141 are connected in series to form a switching regulation circuit 14, which is located between the bus capacitor 13 and the inverter circuit 12, and is used to control or regulate the current from the bus capacitor 13 to the inverter circuit 12, thereby controlling the input voltage of the motor 16.

[0068] The switch regulation circuit 14 of this embodiment includes a second switch S2 and a regulation circuit 141. By setting the second switch S2 and the regulation circuit 141 between the bus capacitor 13 and the inverter circuit 12, the current from the bus capacitor 13 to the inverter circuit 12 can be accurately controlled through the coordinated use of the second switch S2 and the regulation circuit 141.

[0069] According to some embodiments of the present application, Figure 1 As shown, the power supply circuit 10 of this embodiment also includes a first drive circuit 17 and a second drive circuit 18. The first drive circuit 17 is respectively connected to the control module 15 and the first switch S1, and is used to control the first switch S1 to be turned on or off; the second drive circuit 18 is respectively connected to the control module 15 and the second switch S2, and is used to control the second switch S2 to be turned on or off.

[0070] The driving circuit refers to a circuit responsible for converting the control signal of the control module 15 into a signal capable of driving the switch to be turned on or off.

[0071] Optionally, the first drive circuit 17 is used to convert the control signal of the control module 15 into a signal that can drive the first switch S1 to be turned on or off, that is, the control module 15 controls the first switch S1 to be turned on or off through the first drive circuit 17; the second drive circuit 18 is used to convert the control signal of the control module 15 into a signal that can drive the second switch S2 to be turned on or off, that is, the control module 15 controls the second switch S2 to be turned on or off through the second drive circuit 18.

[0072] The control module 15 of this embodiment can accurately control the first switch S1 and the second switch S2 through the first drive circuit 17 and the second drive circuit 18, thereby adjusting the voltage input to the inverter circuit 12 and further adjusting the input voltage of the motor 16 to meet the needs of the motor 16.

[0073] According to some embodiments of the present application, the control module 15 is used to obtain the first voltage U1 and the second voltage U2 when the power supply circuit 10 is powered on, identify the parameters of the motor 16, and obtain the third voltage U3 based on the parameters of the motor 16. The control module 15 is used to control the first switch S1 to be disconnected through the first drive circuit 17 when the third voltage U3 is less than the second voltage U2, and control the second switch S2 to be turned on through the second drive circuit 18.

[0074] In some embodiments, when the power supply circuit 10 is powered on, the control module 15 samples the first voltage U1 and the second voltage U2, identifies the parameters of the motor 16, and obtains the third voltage U3 based on the parameters of the motor 16. The control module 15 first compares the third voltage U3 and the second voltage U2. If the third voltage U3 is less than the second voltage U2, the third voltage U3 and the first voltage U1 are not compared. When the third voltage U3 is less than the second voltage U2, that is, when the bus voltage is greater than the reference voltage, the control module 15 controls the first switch S1 to be disconnected through the first drive circuit 17, and controls the second switch S2 to be turned on through the second drive circuit 18. At this time, the second voltage U2 in the power supply circuit 10 gradually decreases, the inverter circuit 12 is powered by the bus capacitor 13, and the inverter circuit 12 then powers the motor 16, thereby driving the motor 16.

[0075] For example, Figure 2 As shown, when the third voltage U3 is less than the second voltage U2, the control module 15 controls the first switch S1 to be disconnected through the first drive circuit 17 and controls the second switch S2 to be turned on through the second drive circuit 18 during the stage t0 to t1 of the power supply circuit 10. Further, when the third voltage U3 is greater than or equal to the second voltage U2, the control module 15 controls the second switch S2 to be turned off through the second drive circuit 18.

[0076] In this embodiment, when the third voltage U3 is less than the second voltage U2, the control module 15 controls the on and off of the first switch S1 and the second switch S2 through the comparison result, thereby controlling the power supply of the inverter circuit 12, and can effectively control the input voltage of the inverter circuit 12 within the required range, preventing the inverter circuit 12 and the motor 16 from being damaged by excessive voltage.

[0077] According to some embodiments of the present application, the control module 15 is used to obtain the first voltage U1 and the second voltage U2 when the power supply circuit 10 is powered on, identify the parameters of the motor 16, and obtain the third voltage U3 based on the parameters of the motor 16. The control module 15 is used to control the first switch S1 to be disconnected through the first drive circuit 17, and control the second switch S2 to be disconnected through the second drive circuit 18 when the third voltage U3 is greater than the second voltage U2 and the third voltage U3 is less than the first voltage U1.

[0078] When the third voltage U3 is greater than the second voltage U2, and the third voltage U3 is less than the first voltage U1, that is, the bus voltage is less than the reference voltage and the input voltage is greater than the reference voltage, the control module 15 controls the first switch S1 to be disconnected through the first drive circuit 17, and controls the second switch S2 to be disconnected through the second drive circuit 18. At this time, the input voltage and the bus capacitor 13 in the power supply circuit 10 supply power to the inverter circuit 12, that is, the first voltage U1 and the bus capacitor 13 supply power to the inverter circuit 12.

[0079] In some embodiments, when the power supply circuit 10 is powered on, the control module 15 samples the first voltage U1 and the second voltage U2, identifies the parameters of the motor 16, and obtains the third voltage U3 based on the parameters of the motor 16. The control module 15 first compares the third voltage U3 with the second voltage U2, and then compares the third voltage U3 with the first voltage U1. When the third voltage U3 is greater than the second voltage U2 and the third voltage U3 is less than the first voltage U1, the control module 15 controls the first switch S1 to be disconnected through the first drive circuit 17, and controls the second switch S2 to be disconnected through the second drive circuit 18.

[0080] For example, Figure 2 As shown, when the third voltage U3 is greater than the second voltage U2 and less than the first voltage U1, the power supply circuit 10 is in the stage t1-t2; the control module 15 controls the first switch S1 to be disconnected through the first drive circuit 17, and controls the second switch S2 to be disconnected through the second drive circuit 18.

[0081] In this embodiment, when the third voltage U3 is greater than the second voltage U2 and the third voltage U3 is less than the first voltage U1, the first switch S1 and the second switch S2 are controlled to be turned on and off according to the comparison result, thereby controlling the power supply of the inverter circuit 12. The input voltage of the inverter circuit 12 can be effectively controlled within the required range, thereby preventing the inverter circuit 12 and the motor 16 from being damaged by excessive voltage.

[0082] According to some embodiments of the present application, the control module 15 is used to obtain the first voltage U1 and the second voltage U2 when the power supply circuit 10 is powered on, identify the parameters of the motor 16, and obtain the third voltage U3 based on the parameters of the motor 16. The control module 15 is used to control the first switch S1 to be turned on and then turned off at a preset switching frequency through the first drive circuit 17 when the third voltage U3 is greater than the second voltage U2 and the third voltage U3 is greater than or equal to the first voltage U1, and control the second switch S2 to be turned off through the second drive circuit 18.

[0083] The switching frequency refers to a preset fixed frequency value, which is used to control the on and off actions of the first switch S1. The switching frequency determines the number of times the first switch S1 is turned on and off per unit time, that is, the rate of the switching action.

[0084] When the third voltage U3 is greater than the second voltage U2, and the third voltage U3 is greater than or equal to the first voltage U1, that is, the bus voltage is less than the reference voltage and the input voltage is less than the reference voltage, the control module 15 controls the first switch S1 to be turned on and then turned off at a preset switching frequency through the first drive circuit 17; at the same time, the control module 15 controls the second switch S2 to be turned off through the second drive circuit 18. At this time, the power supply circuit 10 works in a boost state, and its circuit model is a boost circuit.

[0085] Optionally, when the first switch S1 is turned on and the second switch S2 is turned off, the bus capacitor 13 in the power supply circuit 10 supplies power to the inverter circuit 12; when the first switch S1 is turned off and the second switch S2 is turned off, the input voltage and inductance L in the power supply circuit 10 supply power to the inverter circuit 12.

[0086] In some embodiments, when the power supply circuit 10 is powered on, the control module 15 samples the first voltage U1 and the second voltage U2, identifies the parameters of the motor 16, and obtains the third voltage U3 based on the parameters of the motor 16. The control module 15 first compares the third voltage U3 with the second voltage U2, and then compares the third voltage U3 with the first voltage U1. When the third voltage U3 is greater than the second voltage U2, and the third voltage U3 is greater than or equal to the first voltage U1, the control module 15 controls the first switch S1 to be turned on and then turned off at a preset switching frequency through the first drive circuit 17, and controls the second switch S2 to be turned off through the second drive circuit 18.

[0087] For example, Figure 2 As shown, when the third voltage U3 is greater than the second voltage U2, and the third voltage U3 is greater than or equal to the first voltage U1, the power supply circuit 10 is in the stage t3-t5. The control module 15 controls the first switch S1 to be turned on and then turned off at a preset switching frequency through the first drive circuit 17, and controls the second switch S2 to be turned off through the second drive circuit 18.

[0088] Optionally, the stage t3 to t5 is a switching cycle of the first switch S1, that is, the difference between t5 and t3 is a cycle time of the switching frequency. The stage t3 to t5 is further divided into two stages, namely the stage t3 to t4 and the stage t4 to t5; the first switch S1 is turned on in the stage t3 to t4, and the first switch S1 is turned off in the stage t4 to t5.

[0089] During the stage t3 to t5, the power supply circuit 10 is a boost circuit, the output voltage is the third voltage U3, and the input voltage is the first voltage U1; the output voltage formula is: U3 = U1 × 1 / (1-d), where d is the on-duty cycle of the first switch S1. It can be deduced that d = 1-U1 / U3, and the value of d is determined by the first voltage U1 and the third voltage U3.

[0090] Since the difference between t5 and t3 is one cycle of the switching frequency, d=(t4-t3) / (t5-t3), that is, the on-duty cycle of the first switch S1 is equal to the difference between t4 and t3 divided by the difference between t5 and t3, and the switching frequency is equal to 1 divided by the difference between t5 and t3. The difference between t5 and t3 can be obtained by calculation, and then the difference between t4 and t3 can be obtained.

[0091] Specifically, when the first switch S1 is turned on and the second switch S2 is turned off, that is, in the stage t3-t4, the voltage of the inductor L is equal to the input voltage, that is, the voltage of the inductor L is equal to the first voltage U1, the current of the inductor L increases linearly, the inductor L stores energy, the second diode D2 is reversely cut off, and the bus capacitor 13 supplies power to the inverter circuit 12.

[0092] When the first switch S1 is disconnected and the second switch S2 is disconnected, that is, in the stage t4-t5, the voltage of the inductor L is equal to the input voltage minus the bus voltage, that is, the voltage of the inductor L is equal to the first voltage U1 minus the second voltage U2, the current of the inductor L decreases linearly, the second diode D2 is turned on, and the input voltage and the inductor L power the inverter circuit 12.

[0093] In this embodiment, when the third voltage U3 is greater than the second voltage U2, and the third voltage U3 is greater than or equal to the first voltage U1, the first switch S1 and the second switch S2 are controlled to be turned on and off by comparing the result, thereby controlling the power supply of the inverter circuit 12. The input voltage of the inverter circuit 12 can be effectively controlled within the required range, thereby preventing the inverter circuit 12 and the motor 16 from not working properly when the voltage is too low.

[0094] According to some embodiments of the present application, the regulation circuit 141 includes a first diode D1 and a first resistor R1, the anode of the first diode D1 is connected to the first end of the second switch S2, the cathode of the first diode D1 is connected between the first input end 121 of the inverter circuit 12 and the positive electrode of the bus capacitor 13, one end of the first resistor R1 is connected between the positive electrode of the first diode D1 and the first end of the second switch S2, and the other end of the first resistor R1 is connected between the first diode D1 and the positive electrode of the bus capacitor 13.

[0095] Optionally, the positive electrode of the first diode D1 serves as the first end of the regulating circuit 141 and is connected to the first end of the second switch S2, and the negative electrode of the first diode D1 serves as the second end of the regulating circuit 141 and is connected between the positive electrode of the bus capacitor 13 and the first input end 121 of the inverter circuit 12.

[0096] The regulating circuit 141 of this embodiment includes a first diode D1 and a first resistor R1. When the second switch S2 is turned on, the bus voltage can be discharged through the first diode D1 and the first resistor R1 to prevent the inverter circuit 12 and the motor 16 from being damaged by excessive voltage.

[0097] According to some embodiments of the present application, the power supply circuit 10 further includes a second diode D2 , an anode of the second diode D2 is connected to the first end of the first switch S1 , and a cathode of the second diode D2 is connected to the positive electrode of the bus capacitor 13 .

[0098] In this embodiment, a second diode D2 is provided between the inductor L and the bus capacitor 13 , thereby ensuring unidirectional flow of current from the inductor L to the bus capacitor 13 .

[0099] According to some embodiments of the present application, the first end of the first drive circuit 17 is connected to the first end of the first switch S1, the second end of the first drive circuit 17 is connected to the second end of the first switch S1, and the third end of the first drive circuit 17 is connected to the first end 151 of the control module 15; the first end of the second drive circuit 18 is connected to the first end of the second switch S2, the second end of the second drive circuit 18 is connected to the second end of the second switch S2, and the third end of the second drive circuit 18 is connected to the second end 152 of the control module 15.

[0100] By connecting the first end of the first switch S1, the second end of the first switch S1 and the first end 151 of the control module 15 respectively through the first drive circuit 17, the control module 15 can control the first end and the second end of the first switch S1 to be connected or disconnected through the first drive circuit 17, thereby controlling the first switch S1 to be turned on or off.

[0101] By connecting the second drive circuit 18 to the first end of the second switch S2, the second end of the second switch S2 and the second end 152 of the control module 15, the control module 15 can control the first end and the second end of the second switch S2 to be connected or disconnected through the second drive circuit 18, thereby controlling the second switch S2 to be turned on or off.

[0102] Another embodiment of the present application further provides a servo drive device, including a motor 16, an encoder and the power supply circuit 10 of the above embodiment.

[0103] In summary, the present application sets a first switch S1 and a switch regulation circuit 14 between the rectifier bridge 11 and the inverter circuit 12, and the control module 15 controls the voltage input from the rectifier bridge 11 to the inverter circuit 12 through the first switch S1 and the switch regulation circuit 14, thereby controlling the input voltage of the motor 16. At this time, the power supply circuit 10 can drive the AC220V motor 16 and the AC380V motor 16 under the AC220V input voltage, that is, drive motors 16 of two voltage levels, and there is no need to design servo drivers of different levels for motors 16 of different voltage levels, so that servo drivers and motors 16 of the same power but different voltage levels can be adapted to each other, thereby reducing the research and development cost of the servo driver and improving the user's convenience; and through the setting of the first switch S1 and the switch regulation circuit 14, when using a bus capacitor 13 with a smaller capacity, the voltage ripple of the bus is reduced, the volume of the bus capacitor 13 is reduced, and then the volume of the servo driver is reduced, the power device is protected, the service life of the bus capacitor 13 is extended, and the probability of false alarm of the servo driver is reduced.

[0104] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A power supply circuit, characterized in that: include: A rectifier bridge, wherein an input end of the rectifier bridge receives mains power and outputs a first voltage based on rectification of the mains power; An inverter circuit, wherein a first input end of the inverter circuit is connected to a first output end of the rectifier bridge, a second input end of the inverter circuit is connected to a second output end of the rectifier bridge, and an output end of the inverter circuit is connected to a motor; A bus capacitor, wherein the positive electrode of the bus capacitor is connected between the first input end of the inverter circuit and the first output end of the rectifier bridge, and the negative electrode of the bus capacitor is connected between the second input end of the inverter circuit and the second output end of the rectifier bridge, and the bus capacitor is used to filter and output a second voltage; an inductor, one end of which is connected to the first output end of the rectifier bridge, and the other end of which is connected to the positive electrode of the bus capacitor; A first switch, wherein a first end of the first switch is connected between the inductor and the positive electrode of the bus capacitor, and a second end of the first switch is connected between the second output end of the rectifier bridge and the negative electrode of the bus capacitor; A switch regulating circuit, disposed between the bus capacitor and the inverter circuit, and used to cooperate with the first switch to control the input voltage of the motor; A control module is respectively connected to the motor, the first switch and the switch regulation circuit, and is used to obtain the first voltage and the second voltage, identify the parameters of the motor, and determine the third voltage based on the parameters of the motor; the control module is used to control the input voltage of the motor through the first switch and the switch regulation circuit based on the third voltage, the first voltage and the second voltage.

2. The power supply circuit according to claim 1, characterized in that: The switch regulation circuit includes a second switch and a regulation circuit, wherein a first end of the second switch is connected to a first end of the regulation circuit, a second end of the regulation circuit is connected between a first input end of the inverter circuit and a positive electrode of the bus capacitor, and a second end of the second switch is connected between a second input end of the inverter circuit and a negative electrode of the bus capacitor.

3. The power supply circuit according to claim 2, characterized in that: The power supply circuit also includes a first drive circuit and a second drive circuit. The first drive circuit is respectively connected to the control module and the first switch to control the first switch to be turned on or off; the second drive circuit is respectively connected to the control module and the second switch to control the second switch to be turned on or off.

4. The power supply circuit according to claim 3, characterized in that: The control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor; The control module is used for controlling the first switch to be disconnected through the first drive circuit when the third voltage is lower than the second voltage, and controlling the second switch to be connected through the second drive circuit.

5. The power supply circuit according to claim 3, characterized in that: The control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor; The control module is used for controlling the first switch to be disconnected through the first drive circuit and controlling the second switch to be disconnected through the second drive circuit when the third voltage is greater than the second voltage and the third voltage is less than the first voltage.

6. The power supply circuit according to claim 3, characterized in that: The control module is used to obtain the first voltage and the second voltage when the power supply circuit is powered on, identify the parameters of the motor, and obtain the third voltage based on the parameters of the motor; The control module is used to control the first switch to be turned on and then turned off at a preset switching frequency through the first drive circuit when the third voltage is greater than the second voltage and the third voltage is greater than or equal to the first voltage, and to control the second switch to be turned off through the second drive circuit.

7. The power supply circuit according to claim 2, characterized in that: The regulation circuit includes a first diode and a first resistor, the anode of the first diode is connected to the first end of the second switch, the cathode of the first diode is connected between the first input end of the inverter circuit and the anode of the bus capacitor, one end of the first resistor is connected between the anode of the first diode and the first end of the second switch, and the other end of the first resistor is connected between the first diode and the anode of the bus capacitor.

8. The power supply circuit according to claim 7, characterized in that: The power supply circuit further includes a second diode, an anode of the second diode is connected to the first end of the first switch, and a cathode of the second diode is connected to the positive electrode of the bus capacitor.

9. The power supply circuit according to claim 3, characterized in that: The first end of the first drive circuit is connected to the first end of the first switch, the second end of the first drive circuit is connected to the second end of the first switch, and the third end of the drive circuit is connected to the first end of the control module; the first end of the second drive circuit is connected to the first end of the second switch, the second end of the second drive circuit is connected to the second end of the second switch, and the third end of the second drive circuit is connected to the second end of the control module.

10. A servo drive device, characterized in that: The invention comprises a motor, an encoder and a power supply circuit as claimed in any one of claims 1 to 9.

Images