Isolation driving circuit and isolation driving system

Abstract

The utility model discloses an isolation driving circuit and an isolation driving system, the isolation driving circuit comprises an inversion module, a coil module, a rectification module and a power supply chip, the inversion module comprises a first switch tube and a second switch tube which are connected in series and is provided with a first node, a first end of the first switch tube is connected with one end of a power supply, and a second end of the second switch tube is connected with the other end of the power supply; the second end of the second switch tube is connected with the other end of the power supply, and the control end of the first switch tube and the control end of the second switch tube are connected with the power supply chip; the coil module comprises a primary coil and a secondary coil, one end of the primary coil is connected with the first node, and the other end of the primary coil is connected with the second end of the second switch tube; the input end of the rectifier module is connected with the output end of the secondary coil, and the output end of the rectifier module is connected with a load. The circuit provided by the utility model can reduce the size of the motor drive circuit, thereby saving the installation space and reducing the cost.

Description

Technical Field

[0001] The utility model relates to the technical field of motor drive, in particular to an isolated drive circuit and an isolated drive system. Background Art

[0002] As an important part of the design of the electric vehicle power system, the design of the motor drive scheme has received extensive research and attention. And its primary task is to design a reliable DCDC power supply to provide a stable supply voltage for 6-way drive and power modules.

[0003] In the related art, most of the motor drive schemes for electric vehicles use 6-way forward or 6-way flyback isolated power supply topologies to supply power to 6 drive chips and IGBT / SIC power modules. This scheme has a high maturity and a relatively simple topology, so it is widely used. However, this scheme usually requires 6 relatively large core transformers, with a high cost and high space requirements. Summary of the Utility Model

[0004] The utility model aims to at least solve one of the technical problems in the related art to some extent. For this reason, the first object of the utility model is to propose an isolated drive circuit. The coil module in the circuit transmits the alternating current generated by the inverter module to the rectifier module, playing a role of electrical isolation, and can reduce the volume of the motor drive circuit, thereby saving the installation space and reducing the cost.

[0005] The second object of the utility model is to propose an isolated drive system.

[0006] To achieve the above object, the first aspect embodiment of the utility model proposes an isolated drive circuit, which includes: an inverter module, a coil module, a rectifier module and a power supply chip. Among them, the inverter module includes a first switch tube and a second switch tube connected in series and has a first node. The first end of the first switch tube is connected to one end of the power supply, the second end of the second switch tube is connected to the other end of the power supply, and the control end of the first switch tube and the control end of the second switch tube are connected to the power supply chip; the coil module includes a primary coil and a secondary coil. One end of the primary coil is connected to the first node, and the other end of the primary coil is connected to the second end of the second switch tube; the input end of the rectifier module is connected to the output end of the secondary coil, and the output end of the rectifier module is connected to the load.

[0007] According to the isolation drive circuit of the embodiment of the present utility model, the power supply chip outputs pulse width modulation signals with a certain frequency respectively, so that the first switching tube and the second switching tube are alternately turned on and off, so as to convert the direct current provided by the power supply into alternating current and transmit it to the primary coil. The primary coil transfers the alternating current to the secondary coil through electromagnetic induction, and the rectification module converts the alternating current into direct current to supply power to the load. Thus, the coil module in this circuit transmits the alternating current generated by the inversion module to the rectification module, playing a role of electrical isolation, and can reduce the volume of the motor drive circuit, thereby saving installation space and reducing costs.

[0008] In addition, the isolation drive circuit according to the above embodiment of the present utility model may further have the following additional technical features:

[0009] Specifically, the first switching tube and the second switching tube are turned on and off according to a preset switching frequency signal output by the power supply chip.

[0010] Specifically, the inversion module further includes: a first capacitor, one end of the first capacitor is connected to the second end of the second switching tube, and the other end of the first capacitor is connected to the other end of the primary coil.

[0011] Specifically, the rectification module includes: a first diode, the positive electrode of the first diode is connected to the first end of the secondary coil, and the negative electrode of the first diode is connected to one end of the load; a second capacitor, one end of the second capacitor is connected to the negative electrode of the first diode, and the other end of the second capacitor is connected to the other end of the load.

[0012] Specifically, the rectification module further includes: a second diode, the negative electrode of the second diode is connected to the positive electrode of the first diode to form a second node, the second node is connected to the first end of the secondary coil, the positive electrode of the second diode is connected to the other end of the load; a third capacitor, one end of the third capacitor is connected to the negative electrode of the first diode; a fourth capacitor, one end of the fourth capacitor is connected to the other end of the third capacitor and has a third node, the other end of the fourth capacitor is connected to the other end of the load, and the third node is connected to the second end of the secondary coil.

[0013] Specifically, the rectification module further includes: a zener diode, the zener diode is connected to one end of the second capacitor, and the other end of the zener diode is connected to the other end of the load.

[0014] Specifically, the primary coil and the secondary coil are coupled and connected in a coreless manner.

[0015] Specifically, the primary coil and the secondary coil are printed on a PCB (Printed Circuit Board), and the PCB has a multi-layer structure with copper wires printed on each layer. The primary coil and the secondary coil are arranged alternately, and the copper wires forming the primary coil are connected through vias, and the copper wires forming the secondary coil are connected through vias.

[0016] Specifically, there is an insulating layer between the primary coil and the secondary coil.

[0017] To achieve the above object, a second aspect embodiment of the present invention provides an isolation drive system, including: the above isolation drive circuit; a power supply connected to the input end of the isolation drive circuit; and a load connected to the output end of the isolation drive circuit.

[0018] According to the isolation drive system of the embodiment of the present invention, through the above isolation drive circuit, the volume of the motor drive circuit can be reduced, thereby saving installation space and reducing costs.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0020] Figure 1 is a hardware topology diagram of an isolation drive circuit according to an embodiment of the present invention;

[0021] Figure 2 is a hardware topology diagram of an isolation drive circuit according to an embodiment of the present invention;

[0022] Figure 3 is a hardware topology diagram of an isolation drive circuit according to an embodiment of the present invention;

[0023] Figure 4 is a layout schematic diagram of a coil module according to an embodiment of the present invention;

[0024] Figure 5 is a block diagram of an isolation drive system according to an embodiment of the present invention. Detailed Embodiment

[0025] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0026] The isolation drive circuit and isolation drive system proposed in the embodiments of the present invention will be described below with reference to the accompanying drawings.

[0027] Figure 1 It is a hardware topology diagram of the isolation drive circuit according to the embodiments of the present invention.

[0028] As Figure 1 shown, the isolation drive circuit 100 in the embodiments of the present invention may include: an inverter module 110, a coil module 120, a rectifier module 130, and a power supply chip 140.

[0029] Among them, the inverter module 110 includes a first switching tube Q1 and a second switching tube Q2 connected in series and having a first node. The first end of the first switching tube Q1 is connected to one end of the power supply, the second end of the second switching tube Q2 is connected to the other end of the power supply, and the control ends of the first switching tube Q1 and the second switching tube Q2 are connected to the power supply chip 140; the coil module 120 includes a primary coil 121 and a secondary coil 122. One end of the primary coil 121 is connected to the first node, and the other end of the primary coil 121 is connected to the second end of the second switching tube Q2; the input end of the rectifier module 130 is connected to the output end of the secondary coil 122, and the output end of the rectifier module 130 is connected to the load. Among them, for the sake of easy understanding, Figure 1 the first switching tube Q1 and the second switching tube Q2 in

[0030] Specifically, as Figure 1As shown in the figure, the positive pole of the power supply is connected to the first end of the first switching transistor Q1, and the negative pole of the power supply is connected to the second end of the second switching transistor Q2. The power supply chip 140 can respectively send pulse width modulation signals with a certain frequency to the control ends of the first switching transistor Q1 and the second switching transistor Q2, so that the first switching transistor Q1 and the second switching transistor Q2 are alternately turned on, so as to convert the direct current provided by the power supply into alternating current and transmit it to the primary coil 121. The primary coil 121 and the secondary coil 122 in the coil module 120 are wound in a certain way to form a coreless transformer. The primary coil 121 and the secondary coil 122 are close to each other to generate an electromagnetic induction phenomenon, so that the alternating current in the primary coil 121 can be transmitted to the secondary coil 122. Compared with the core transformer used in the related technology, it can reduce the volume of the motor drive circuit, thus saving installation space and reducing costs. Among them, the number of turns of the primary coil 121 and the secondary coil 122 can be multiple turns respectively, which can improve the power transmission efficiency of the coil module 120. The rectification module 130 can convert the alternating current output by the secondary coil 122 into direct current and output it to the load to supply power to the load. Thus, the coil module 120 transmits the alternating current generated by the inversion module 110 to the rectification module 130 and plays the role of electrical isolation.

[0031] According to an embodiment of the present invention, the first switching transistor Q1 and the second switching transistor Q2 are turned on and off according to a preset switching frequency signal output by the power supply chip 140. Among them, the preset switching frequency can be calibrated according to the actual situation. For example, the preset switching frequency can be 20 MHz.

[0032] According to an embodiment of the present invention, as Figure 2 shown, the inversion module 110 further includes: a first capacitor C1, one end of the first capacitor C1 is connected to the second end of the second switching transistor Q2, and the other end of the first capacitor C1 is connected to the other end of the primary coil 121.

[0033] Specifically, the first capacitor C1 is a resonant capacitor. When the second switching transistor Q2 is in the on state, the first capacitor C1 and the primary coil 121 resonate, and the resonant frequency of the resonance between the first capacitor C1 and the primary coil 121 is the same as the switching frequency of the first switching transistor Q1.

[0034] According to an embodiment of the present invention, as Figure 2 shown, the rectification module 130 includes: a first diode D1 and a second capacitor C2. Among them, the positive pole of the first diode D1 is connected to the first end of the secondary coil 122, and the negative pole of the first diode D1 is connected to one end of the load; one end of the second capacitor C2 is connected to the negative pole of the first diode D1, and the other end of the second capacitor C2 is connected to the other end of the load.

[0035] According to an embodiment of the present utility model, as Figure 2 shown, the rectification module 130 further includes: a second diode D2, a third capacitor C3, and a fourth capacitor C4. Wherein, the negative electrode of the second diode D2 is connected to the positive electrode of the first diode D1 to form a second node, the second node is connected to the first end of the secondary coil 122, and the positive electrode of the second diode D2 is connected to the other end of the load; one end of the third capacitor C3 is connected to the negative electrode of the first diode D1; one end of the fourth capacitor C4 is connected to the other end of the third capacitor C3 and has a third node, the other end of the fourth capacitor C4 is connected to the other end of the load, and the third node is connected to the second end of the secondary coil 122.

[0036] Specifically, the alternating current output by the secondary coil 122 is rectified by the first diode D1 and the second diode D2 and converted into direct current to supply power to the load. The second capacitor C2 can filter the direct current, thereby improving the stability of the output voltage of the rectification module 130. The third capacitor C3 and the fourth capacitor C4 can smooth the rectified direct current.

[0037] According to an embodiment of the present utility model, as Figure 3 shown, the rectification module 130 further includes: a zener diode DZ1. The zener diode DZ1 is connected to one end of the second capacitor C2, and the other end of the zener diode DZ1 is connected to the other end of the load.

[0038] Specifically, the zener diode DZ1 can clamp the output voltage of the rectification module 130, and can avoid excessive voltage being output to the load.

[0039] According to an embodiment of the present utility model, the primary coil 121 and the secondary coil 122 are coupled and connected in a coreless manner.

[0040] Specifically, the primary coil 121 and the secondary coil 122 in the coil module 120 are coupled and connected in a coreless manner, and are wound in a certain way to form a coreless transformer. The primary coil 121 and the secondary coil 122 are close to each other to generate an electromagnetic induction phenomenon, so that the alternating current in the primary coil 121 can be transmitted to the secondary coil 122. Compared with the core transformer used in the related art, the material cost of the transformer is saved, and there is no height limit; at the same time, since there is no core, there is no magnetic saturation and core loss, and it is easy to achieve high power density.

[0041] According to an embodiment of the present utility model, the primary coil 121 and the secondary coil 122 are printed on a PCB board. The PCB board has a multi-layer structure, and copper wires are printed on each layer structure. The primary coil 121 and the secondary coil 122 are alternately arranged, and the copper wires forming the primary coil 121 are connected through vias, and the copper wires forming the secondary coil 122 are connected through vias

[0042] Furthermore, according to an embodiment of the present invention, there is an insulating layer between the primary coil 121 and the secondary coil 122.

[0043] Specifically, the primary coil 121 and the secondary coil 122 are printed on a PCB board. Different layers are used to print copper wires as coils, and the coil types of adjacent layers are different. The PCB board is used as the magnetic field propagation medium. Exemplarily, as Figure 4 shown in the six-layer PCB board, the coils on the second and fourth layers ( Figure 4 the blue coils in) are the primary coil 121, and the coils on the third and fifth layers ( Figure 4 the red coils in) are used as the secondary coil 122. The coils of the same type are connected through vias. The composition of multiple primary coils 121 and secondary coils 122 can increase the coupling coefficient of the coil module 120. The insulating layer between the primary coil 121 and the secondary coil 122 can be the PCB material, so that the primary coil 121 and the secondary coil 122 are insulated from each other. Compared with traditional transformers, PCB coils have the advantages of being easy to manufacture, having good consistency, being able to meet strict height and space requirements, having high insulation withstand voltage, and low cost.

[0044] In summary, for the isolation drive circuit according to the embodiment of the present invention, the power supply chip outputs pulse width modulation signals of a certain frequency respectively, so that the first switching tube and the second switching tube are alternately turned on, so as to convert the direct current provided by the power supply into alternating current and transmit it to the primary coil. The primary coil transfers the alternating current to the secondary coil through electromagnetic induction, and the rectification module converts the alternating current into direct current to supply power to the load. Thus, the coil module in this circuit transmits the alternating current generated by the inversion module to the rectification module, playing a role of electrical isolation, and can reduce the volume of the motor drive circuit, thereby saving installation space and reducing costs.

[0045] Corresponding to the above embodiment, the present invention also proposes an isolation drive system.

[0046] Figure 5 It is a block diagram of the isolation drive system according to the embodiment of the present invention.

[0047] As Figure 5 shown, the isolation drive system 200 according to the embodiment of the present invention includes: the isolation drive circuit 100 of the above embodiment; a power supply 210, the power supply 210 is connected to the input end of the isolation drive circuit 100; a load 220, the load 220 is connected to the output end of the isolation drive circuit 100.

[0048] According to the isolation drive system of the embodiments of the present utility model, through the above-mentioned isolation drive circuit, the volume of the motor drive circuit can be reduced, thereby saving the installation space and reducing the cost.

[0049] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0050] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0051] In the present utility model, unless otherwise clearly specified and defined, terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0052] Although the embodiments of the present utility model have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as a limitation to the present utility model. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present utility model.

Claims

1. An isolation driving circuit, characterized in that: The circuit includes: an inverter module, a coil module, a rectifier module and a power chip, wherein: The inverter module includes a first switch tube and a second switch tube connected in series and having a first node, a first end of the first switch tube is connected to one end of a power supply, a second end of the second switch tube is connected to the other end of the power supply, and a control end of the first switch tube and a control end of the second switch tube are connected to the power chip; The coil module comprises a primary coil and a secondary coil, one end of the primary coil is connected to the first node, and the other end of the primary coil is connected to the second end of the second switch tube; The input end of the rectifier module is connected to the output end of the secondary coil, and the output end of the rectifier module is connected to the load.

2. The isolation driving circuit according to claim 1, characterized in that: The first switch tube and the second switch tube are turned on and off according to a preset switching frequency signal output by the power chip.

3. The isolation driving circuit according to claim 1, characterized in that: The inverter module also includes: A first capacitor, one end of the first capacitor is connected to the second end of the second switch tube, and the other end of the first capacitor is connected to the other end of the primary coil.

4. The isolation driving circuit according to claim 1, characterized in that: The rectifier module comprises: a first diode, wherein an anode of the first diode is connected to a first end of the secondary coil, and a cathode of the first diode is connected to one end of the load; A second capacitor, one end of the second capacitor is connected to the cathode of the first diode, and the other end of the second capacitor is connected to the other end of the load.

5. The isolation driving circuit according to claim 4, characterized in that: The rectifier module also includes: a second diode, wherein a cathode of the second diode is connected to an anode of the first diode to form a second node, the second node is connected to a first end of the secondary coil, and an anode of the second diode is connected to the other end of the load; a third capacitor, one end of the third capacitor being connected to the cathode of the first diode; A fourth capacitor, one end of the fourth capacitor is connected to the other end of the third capacitor and has a third node, the other end of the fourth capacitor is connected to the other end of the load, and the third node is connected to the second end of the secondary coil.

6. The isolation driving circuit according to claim 4, characterized in that: The rectifier module also includes: A voltage regulator diode is connected to one end of the second capacitor, and the other end of the voltage regulator diode is connected to the other end of the load.

7. The isolation driving circuit according to claim 1, characterized in that: The primary coil and the secondary coil are coupled and connected in a coreless manner.

8. The isolation driving circuit according to claim 2, characterized in that: The primary coil and the secondary coil are printed on a PCB board, the PCB board has a multi-layer structure, copper wires are printed on each layer of the structure, the primary coil and the secondary coil are alternately arranged, the copper wires constituting the primary coil are connected through vias, and the copper wires constituting the secondary coil are connected through vias.

9. The isolation driving circuit according to claim 8, characterized in that: An insulating layer is provided between the primary coil and the secondary coil.

10. An isolation drive system, characterized in that: include: The isolation driving circuit according to any one of claims 1 to 9; A power supply connected to an input terminal of the isolation drive circuit; A load is connected to the output end of the isolation driving circuit.

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