Hybrid switch circuit, electric drive controller and vehicle

Abstract

The invention relates to a hybrid switch circuit, an electric drive controller and a vehicle. The hybrid switching circuit may include: a first power switch and a second power switch in parallel, the first power switch and the second power switch being of different types; the first driving loop is connected with the first power switch and is used for driving the first power switch to be switched on or switched off; the second driving loop is connected with the second power switch and is used for driving the second power switch to be switched on or switched off; the current suppression unit is arranged on a first branch in a target driving loop and is used for suppressing circulating current of a grounding loop in the hybrid switching circuit, the first branch is a branch in the grounding loop, and the target driving loop is a driving loop for driving a target power switch; the target power switch is a delayed conduction power switch in the first power switch and the second power switch. Therefore, the circulating current on the ground loop is suppressed, the switching speed of the power switch is prevented from being influenced, and the efficiency of the hybrid switch is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of electric drive controllers, and in particular to a hybrid switch circuit, an electric drive controller and a vehicle. Background Art

[0002] In order to improve the efficiency and power density of the power electronic converter in the electric drive controller, a hybrid parallel technology of different types of power switches is usually adopted. For example, a power switch with low switching power consumption and a power switch with high current carrying capacity and low cost are mixed and connected in parallel, so that the power switch with low switching power consumption can bear the switching loss of the hybrid switch, and the two can jointly bear the conduction loss. Therefore, the power consumption and cost of the electric drive controller can be reduced, thereby improving the efficiency of the electric drive controller. Summary of the invention

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a hybrid switching circuit, an electric drive controller and a vehicle.

[0004] According to a first aspect of an embodiment of the present disclosure, a hybrid switch circuit is provided, the hybrid switch circuit comprising: A first power switch and a second power switch connected in parallel, wherein the first power switch and the second power switch are of different types; A first driving circuit, wherein the first driving circuit is connected to the first power switch and is used to drive the first power switch to be turned on or off; A second driving circuit, the second driving circuit is connected to the second power switch and is used to drive the second power switch to be turned on or off; A current suppression unit, wherein the current suppression unit is arranged on a first branch in a target drive circuit, and is used to suppress a circulating current of a ground circuit in the hybrid switch circuit, wherein the first branch is a branch in the ground circuit, the target drive circuit is a drive circuit for driving a target power switch, and the target power switch is a power switch with delayed conduction between the first power switch and the second power switch.

[0005] Optionally, the current suppression unit includes a switching device; The switch device is used to be disconnected during the conduction process of another power switch other than the target power switch, so as to suppress the circulating current of the ground loop; The switch device is further configured to be turned on when the target power switch is turned on.

[0006] Optionally, the switching device includes a first P-type MOS tube, the drain of the first P-type MOS tube is connected to the emitter of the target power switch, the source of the first P-type MOS tube is grounded, and the gate of the P-type MOS tube is used to input a third drive signal that controls the first P-type MOS tube to be turned on or off.

[0007] Optionally, the switching device also includes a second P-type MOS tube, the source of the second P-type MOS tube is connected to the source of the first P-type MOS tube, the drain of the second P-type MOS tube is grounded, and the gate of the second P-type MOS tube is used to input a fourth drive signal for controlling the second P-type MOS tube to be turned on or off.

[0008] Optionally, the current suppression unit includes a first component, which is in a low impedance state in a low frequency band and in a high impedance state in a high frequency band.

[0009] Optionally, the first driving circuit further includes a first switch, a second switch and a driving power supply, and the second driving circuit further includes a third switch, a fourth switch and a driving power supply; the driving power supply includes a first power supply and a second power supply, and the negative electrode of the first power supply is connected to the positive electrode of the second power supply; The first switch is located between the negative electrode of the second power supply and the first power switch, the second switch is located between the positive electrode of the first power supply and the first power switch, the third switch is located between the negative electrode of the second power supply and the second power switch, and the fourth switch is located between the positive electrode of the first power supply and the second power switch.

[0010] Optionally, the hybrid switch circuit further comprises: a first control device; The first control device is connected to the first switch, the second switch, the third switch and the fourth switch, respectively, and is used to control the first switch, the second switch, the third switch and the fourth switch to be turned on and off according to a preset switch timing, so that the target power switch is delayed to be turned on and / or turned off in advance.

[0011] Optionally, if the switching loss of the first power switch is lower than the switching loss of the second power switch, the second power switch delays the turn-on of the first power switch, the target power switch is the second power switch, and the target drive circuit is the second drive circuit.

[0012] Optionally, the first power switch is a silicon carbide field effect transistor, and / or the second power switch is a silicon insulated gate bipolar transistor.

[0013] Optionally, a ground terminal of the first driving circuit is different from a ground terminal of the second driving circuit.

[0014] Optionally, the hybrid switch circuit further includes: a junction temperature detection device and a second control device; The junction temperature detection device is connected to another power switch other than the target power switch, and is configured to detect the junction temperature of another power switch other than the target power switch; The second control device is respectively connected to the junction temperature detection device and another drive circuit other than the target drive circuit, and is configured to adjust, according to the junction temperature, the duration of an electrical signal for controlling another power switch other than the target power switch to be in an off state in the another drive circuit.

[0015] Optionally, the junction temperature detection device includes a temperature detection unit, a current detection unit, and a processing unit; The temperature detection unit is configured to detect the temperature of another power switch other than the target power switch; The current detection unit is configured to detect the current flowing through another power switch other than the target power switch when the first power switch and the second power switch are in an on state; The processing unit is connected to the temperature detection unit and the current detection unit, and is configured to determine the junction temperature of the another power switch at the end of the current drive cycle according to the temperature, the current, and the duration of an electrical signal for controlling the another power switch to be in an off state within the current drive cycle.

[0016] Optionally, the second control device is connected to the processing unit, and is configured to, if the junction temperature of the another power switch at the end of the current drive cycle is less than a preset junction temperature threshold, reduce the duration of an electrical signal for controlling the another power switch to be in an off state in the next drive cycle, and, if the junction temperature of the another power switch at the end of the current drive cycle is greater than the preset junction temperature threshold, increase the duration of an electrical signal for controlling the another power switch to be in an off state in the next drive cycle.

[0017] According to a second aspect of the embodiments of the present disclosure, an electric drive controller is provided, including the hybrid switch circuit as described in the first aspect of the embodiments of the present disclosure.

[0018] According to a third aspect of the embodiments of the present disclosure, a vehicle is provided, including the electric drive controller as described in the second aspect of the embodiments of the present disclosure.

[0019] By adopting the above technical solution, a current suppression unit is arranged on the first branch of the target drive loop to suppress the circulating current of the ground loop in the hybrid switch circuit, wherein the first branch is also a branch in the ground loop, the target drive loop is a drive loop that drives the target power switch, and the target power switch is a power switch that is delayed in conduction among the first power switch and the second power switch. In this way, the current suppression unit is arranged on the first branch in the target drive loop. On the one hand, it does not affect the normal conduction and disconnection of another power switch other than the target power switch. On the other hand, the current suppression unit suppresses the circulating current on the first branch, and then suppresses the circulating current of the ground loop including the first branch, avoiding the induced voltage generated on the stray inductance and the voltage of another power switch other than the target power switch to form negative feedback, avoiding affecting the conduction and disconnection speed of the power switch, thereby reducing the switching loss of the power switch and improving the efficiency of the hybrid switch.

[0020] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0022] Figure 1 is a hybrid switch circuit diagram in the related art according to an exemplary embodiment.

[0023] Figure 2 is a schematic diagram of a hybrid switch circuit according to an exemplary embodiment.

[0024] Figure 3 is a schematic diagram of another hybrid switch circuit according to an exemplary embodiment.

[0025] Figure 4 is a schematic diagram of another hybrid switch circuit according to an exemplary embodiment.

[0026] Figure 5 is a schematic diagram of yet another hybrid switch circuit according to an exemplary embodiment.

[0027] Figure 6 is a schematic diagram of a driving signal according to an exemplary embodiment.

[0028] Figure 7 1 is a timing diagram of a third driving signal, a fourth driving signal and a driving signal of a silicon carbide field effect transistor SiC MOSFET according to an exemplary embodiment. DETAILED DESCRIPTION

[0029] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0030] It should be noted that all actions of acquiring signals, information or data in the present disclosure are carried out in compliance with the relevant data protection laws and policies of the country where the device is located and with the authorization given by the owner of the corresponding device.

[0031] In the technology of hybrid parallel connection of different types of power switches, since the power switch with lower switching power consumption bears the switching loss of the hybrid switch, the two types of power switches in the hybrid parallel connection are not turned on and off at the same time, which will cause different currents in the main circuits of the different types of power switches, thereby forming a voltage difference in the ground equivalent inductance of the main circuit. The voltage difference will form a circulating current through the ground circuit, and the circulating current will generate a voltage on the ground equivalent inductance (hereinafter referred to as the stray inductance). The direction of the voltage is opposite to the direction of the voltage of the turned-on power switch, which will generate negative feedback on the conduction process and disconnection process of the hybrid switch, reduce the speed of conduction and disconnection, thereby increasing the switching loss and affecting the efficiency of the hybrid switch.

[0032] Figure 1 FIG. 1 is a hybrid switch circuit diagram in a related art according to an exemplary embodiment. Figure 1 As shown, the first power switch and the second power switch are connected in parallel, the positive electrode of the first power supply VCC1 is connected to the first power switch through the second switch K2 and the driving resistor R1, and the negative electrode of the second power supply VCC2 is connected to the first power switch through the first switch K1 and the driving resistor R1. The positive electrode of the first power supply VCC1 is connected to the second power switch through the fourth switch K4 and the driving resistor R2, and the negative electrode of the second power supply VCC2 is connected to the second power switch through the third switch K3 and the driving resistor R2. The negative electrode of the first power supply VCC1 is connected to the positive electrode of the second power supply VCC2. Among them, the first power switch can be a silicon carbide field effect transistor SiC MOSFET, and the second power switch can be a silicon insulated gate bipolar transistor Si IGBT.

[0033] Taking the hybrid switch on stage as an example, the second switch K2 is closed first, and the first power supply VCC1 first drives the first power switch to turn on through the driving resistor R1. After the first power switch is turned on, most of the current I1 flows through the first stray inductor L1 in the loop where the first power switch is located, and a voltage V1 with a positive top and a negative bottom is generated on the first stray inductor L1. A very small part of the current will flow through the second stray inductor L2 in the loop where the second power switch is located, and a voltage V2 with a positive top and a negative bottom will be generated on the second stray inductor L2. Since the current on the first stray inductor L1 is much larger than the second stray inductor L2, that is, the current change rate on the first stray inductor L1 is greater than that on the second stray inductor L2. The current change rate on the stray inductor L2, therefore, the voltage V1 generated on the first stray inductor L1 is much greater than the voltage V2 generated on the second stray inductor L2, and in the ground loop of the hybrid switch circuit (the loop where the first stray inductor L1, the second stray inductor L2, the third stray inductor L3 and the fourth stray inductor L4 are located), a circulating current loop is formed from the first stray inductor L1 through the third stray inductor L3 and the fourth stray inductor L4 to the second stray inductor L2, that is, a ground loop is formed. Among them, the current on the third stray inductor L3 is shown as I2 in the figure. According to Lenz's theorem, an induced voltage V3 with positive on the left and negative on the right will be generated on the third stray inductor L3. At this time, the first power switch is in the on state, and its on voltage is opposite to the induced voltage V3, forming a negative feedback, resulting in a slower on-speed of the first power switch, affecting the on-speed, thereby increasing the switching loss of the first power switch and affecting the efficiency of the hybrid switch.

[0034] In view of this, the present disclosure provides a hybrid switch circuit, an electric drive controller and a vehicle, wherein a current suppression unit is arranged on the first branch in the target drive circuit to suppress the circulating current of the ground circuit, wherein the first branch is a branch in the ground circuit, the target drive circuit is a drive circuit that drives the target power switch, and the target power switch is a power switch that is delayed in conduction among the first power switch and the second power switch. In this way, the current suppression unit is arranged on the first branch in the target drive circuit, which, on the one hand, does not affect the normal conduction and disconnection of another power switch other than the target power switch, and on the other hand, the current suppression unit suppresses the circulating current on the first branch, thereby suppressing the circulating current of the ground circuit including the first branch, avoiding the induced voltage generated on the stray inductance and the voltage of another power switch other than the target power switch to form a negative feedback, avoiding affecting the conduction and disconnection speed of the power switch, thereby reducing the switching loss of the power switch and improving the efficiency of the hybrid switch.

[0035] Combine the following Figures 2 to 5 The hybrid switch circuit provided by the present disclosure is described.

[0036] like Figures 2 to 5As shown, the hybrid switch circuit provided by the present disclosure includes: a first power switch and a second power switch in parallel, wherein the first power switch and the second power switch are of different types; the hybrid switch circuit also includes a first drive circuit and a second drive circuit, wherein the first drive circuit is connected to the first power switch and is used to drive the first power switch to be turned on or off, and the second drive circuit is connected to the second power switch and is used to drive the second power switch to be turned on or off; and the hybrid switch circuit also includes a current suppression unit, which is arranged on a first branch in a target drive circuit and is used to suppress the circulating current of a grounding circuit in the hybrid switch circuit, the first branch is a branch in the grounding circuit, the target drive circuit is a drive circuit that drives a target power switch, and the target power switch is a power switch with delayed turn-on in the first power switch and the second power switch.

[0037] In the present disclosure, one of the first power switch and the second power switch has lower switching loss. Assuming that the switching loss of the first power switch is lower than the switching loss of the second power switch, the second power switch in the hybrid switch delays the conduction of the first power switch, that is, the target power switch mentioned in the present disclosure is the second power switch, and the target drive circuit is the second drive circuit.

[0038] Considering that silicon carbide field effect transistors (SiC MOSFET) are considered to be the preferred alternative to traditional silicon insulated gate bipolar transistors (Si IGBT) in many applications. Silicon carbide field effect transistors SiCMOSFET have lower switching losses and on-resistance; silicon insulated gate bipolar transistors Si IGBT have advantages in conduction characteristics at high currents due to the conductivity modulation effect, and have relatively low costs. Therefore, in the present disclosure, the first power switch can be a silicon carbide field effect transistor SiC MOSFET, and / or, the second power switch can be a silicon insulated gate bipolar transistor Si IGBT. In addition, the first power switch can also be a transistor with low switching power consumption such as a gallium nitride field effect transistor GaN MOSFET.

[0039] The first drive loop may include a first drive power supply, a drive resistor R1 and a first power switch, the first power switch may be a silicon carbide field effect transistor SiC MOSFET, and the capacitor C1 is the equivalent capacitance of the silicon carbide field effect transistor SiC MOSFET. The second drive loop may include a second drive power supply, a drive resistor R2 and a second power switch, the second power switch may be a silicon insulated gate bipolar transistor Si IGBT, and the capacitor C2 is the equivalent capacitance of the silicon insulated gate bipolar transistor Si IGBT. In addition, the first drive loop and the second drive loop also include a branch in the ground loop of the hybrid switch circuit, for example, Figure 2-Figure 5In the embodiment, the first driving loop further includes a branch in the grounding loop where the third stray inductance L3 is located, and the second driving loop further includes a branch in the grounding loop where the fourth stray inductance L4 is located.

[0040] It should be understood that the first driving power source and the second driving power source may be the same or different. For example, the first driving circuit and the second driving circuit may share the same driving power source. Figures 2 to 4 As shown, the first driving circuit and the second driving circuit share the same driving power supply, and the driving power supply may include a first power supply VCC1 and a second power supply VCC2. For example, the first driving circuit and the second driving circuit may use different driving power supplies, such as Figure 5 As shown, the first driving circuit adopts the first driving power supply VCC3, the second driving circuit adopts the second driving power supply VCC4, and the first driving power supply VCC3 and the second driving power supply VCC4 are independently provided.

[0041] In the present disclosure, the current suppression unit is arranged on the first branch in the target drive circuit, and the first branch is a branch in the hybrid switch ground circuit, that is, the first branch is a branch shared by the target drive circuit and the ground circuit. Figure 2-Figure 4 , assuming that the target power switch is the second power switch, the first branch may be the branch where the fourth miscellaneous inductor L4 is located.

[0042] The current suppression unit is arranged on the first branch in the target drive circuit. On the one hand, it does not affect the normal conduction and disconnection of another power switch except the target power switch. On the other hand, the current suppression unit suppresses the circulating current on the first branch, thereby suppressing the circulating current of the grounding circuit including the first branch.

[0043] By adopting the above technical solution, a current suppression unit is arranged on the first branch of the target drive loop to suppress the circulating current of the ground loop in the hybrid switch circuit, wherein the first branch is also a branch in the ground loop, the target drive loop is a drive loop that drives the target power switch, and the target power switch is a power switch that is delayed in conduction among the first power switch and the second power switch. In this way, the current suppression unit is arranged on the first branch in the target drive loop. On the one hand, it does not affect the normal conduction and disconnection of another power switch other than the target power switch. On the other hand, the current suppression unit suppresses the circulating current on the first branch, and then suppresses the circulating current of the ground loop including the first branch, avoiding the induced voltage generated on the stray inductance and the voltage of another power switch other than the target power switch to form negative feedback, avoiding affecting the conduction and disconnection speed of the power switch, thereby reducing the switching loss of the power switch and improving the efficiency of the hybrid switch.

[0044] In addition, if Figures 2 to 4As shown, the first drive circuit also includes a first switch, a second switch and a drive power supply, the second drive circuit includes a third switch, a fourth switch and a drive power supply, the drive power supply includes a first power supply and a second power supply, and the negative pole of the first power supply is connected to the positive pole of the second power supply.

[0045] Among them, the first switch K1 is located between the negative pole of the second power supply VCC2 and the first power switch, the second switch K2 is located between the positive pole of the first power supply VCC1 and the first power switch, the third switch K3 is located between the negative pole of the second power supply VCC2 and the second power switch, and the fourth switch K4 is located between the positive pole of the first power supply and the second power switch.

[0046] The first driving circuit and the second driving circuit share a driving power supply, that is, share a first power supply VCC1 and a second power supply VCC2.

[0047] The first power switch can be controlled to be turned on when the second switch K2 is closed and the first switch K1 is opened, and the second power switch can be controlled to be turned on when the fourth switch K4 is closed and the third switch K3 is opened. The first power switch is controlled to be opened when the first switch K1 is closed and the second switch K2 is opened, and the second power switch is controlled to be opened when the fourth switch K4 is opened and the third switch K3 is closed.

[0048] Figure 6 FIG. 1 is a schematic diagram showing a driving signal according to an exemplary embodiment. Figure 6 As shown, the second switch K2 can be controlled to be closed and opened according to the first drive signal, and the fourth switch K4 can be controlled to be closed and opened according to the second drive signal. Among them, in the first drive signal and the second drive signal, the high level represents that the first power switch is turned on, and the low level represents that the first power switch is turned off. Similarly, in the second drive signal, the high level represents that the second power switch is turned on, and the low level represents that the second power switch is turned off. In this way, when the first power switch is a silicon carbide field effect transistor SiC MOSFET, the purpose of early turning on of the silicon carbide field effect transistor SiC MOSFET and delayed disconnection can be achieved.

[0049] It should be understood that the first switch K1 and the second switch K2 are mutually exclusive, the second switch K2 is disconnected when the first switch K1 is closed, and the second switch K2 is closed when the first switch K1 is disconnected. Similarly, the third switch K3 and the fourth switch K4 are mutually exclusive, the fourth switch K4 is disconnected when the third switch K3 is closed, and the fourth switch K4 is closed when the third switch K3 is disconnected.

[0050] The hybrid switch circuit may further include a first control device (not shown in the figure). The first control device is connected to the first switch, the second switch, the third switch and the fourth switch respectively, and is used to control the first switch, the second switch, the third switch and the fourth switch according to a preset switch timing sequence, so that the target power switch is delayed in conduction and / or disconnected in advance.

[0051] In one embodiment, the current suppression unit may include a switch device, which is used to be turned off during the conduction of another power switch other than the target power switch to suppress the circulating current of the ground loop, and is used to be turned on when the target power switch is turned on.

[0052] For example, see Figures 2 to 4 Assuming that the target power switch is the second power switch, the first branch may be the branch where the fourth stray inductor L4 is located, and when the first power switch, i.e., the silicon carbide field effect transistor SiC MOSFET, is turned on, the switch device is in an off state, and when the second power switch, i.e., the silicon insulated gate bipolar transistor Si IGBT, is turned on, the switch device is in an on or closed state.

[0053] In one implementation of this embodiment, the switch device may be a manually controlled switch, such as a relay. In this implementation, the switch device disposed on the first branch of the second drive loop does not require electrical signal control. During the conduction of the silicon carbide field effect transistor SiC MOSFET, the switch device is manually controlled to be disconnected, and when the silicon insulated gate bipolar transistor Si IGBT is turned on, the switch device is manually controlled to be turned on or closed.

[0054] In another implementation of this embodiment, the switch device may be a switch controlled by an electrical signal, for example, the switch device is a field effect transistor, and a power supply is required in the hybrid switch circuit to control the field effect transistor. By way of example, the switch device may include a first P-type MOS transistor Q1, the drain of the first P-type MOS transistor being connected to the emitter of the target power switch, the source of the first P-type MOS transistor being grounded, and the gate of the P-type MOS transistor being used to input a third drive signal for controlling the first P-type MOS transistor to be turned on or off. The first P-type MOS transistor Q1 is turned on when the third drive signal is at a low level, and the first P-type MOS transistor Q1 is turned off when the third drive signal is at a high level.

[0055] Using the above example, Figure 2 As shown, the drain of the first P-type MOS transistor Q1 is connected to the emitter of the silicon insulated gate bipolar transistor SiIGBT, the source of the first P-type MOS transistor Q1 is grounded, and the gate of the first P-type MOS transistor Q1 is used to input a first driving signal for controlling the first P-type MOS transistor to be turned on or off (the connection relationship of the gate of the P-type MOS transistor is not shown in FIG. Figure 2As shown in FIG, when the gate of the silicon carbide field effect transistor SiC MOSFET is at a high level, the silicon carbide field effect transistor SiC MOSFET is turned on, and the first drive signal can control the first P-type MOS tube to be turned off; when the gate of the silicon carbide field effect transistor SiC MOSFET is at a low level, the silicon carbide field effect transistor SiC MOSFET is turned off, and at this time, the first drive signal controls the first P-type MOS tube Q1 to be turned on.

[0056] use Figure 2 The circuit shown can suppress the circulating current of the ground loop during the hybrid switch on process. However, during the hybrid switch off process, due to the diode characteristics in the first P-type MOS transistor Q1, there is a circulating current from right to left in the first P-type MOS transistor Q1. Therefore, in order to suppress the circulating current existing during the hybrid switch off process, in another implementation of this embodiment, the switch device further includes a second P-type MOS transistor. Figure 3 As shown, the second P-type MOS transistor Q2 is connected in antiphase series with the first P-type MOS transistor, that is, the source of the second P-type MOS transistor Q2 is connected to the source of the first P-type MOS transistor Q1, the drain of the second P-type MOS transistor Q2 is grounded, and the gate of the second P-type MOS transistor Q2 is used to input the fourth drive signal for controlling the second P-type MOS transistor to be turned on or off. The second P-type MOS transistor Q2 is turned on when the fourth drive signal is at a low level, and the second P-type MOS transistor Q2 is turned off when the fourth drive signal is at a high level.

[0057] For example, Figure 7 1 is a timing diagram of a third driving signal, a fourth driving signal and a driving signal of a silicon carbide field effect transistor SiC MOSFET according to an exemplary embodiment. Figure 7 As shown, during the turn-on process of the silicon carbide field effect transistor SiCMOSFE, the third drive signal is at a high level to control the first P-type MOS tube Q1 to be temporarily disconnected. At this time, the first P-type MOS tube Q1 can be used to block the circulating current of the ground loop during the conduction process of the hybrid switch, ensuring that the silicon carbide field effect transistor SiC MOSFE is not affected by the circulating current during the turn-on process. After the silicon carbide field effect transistor SiC MOSFE is turned on, the third drive signal is at a low level to turn on the first P-type MOS tube Q1, thereby ensuring that the conduction process of the silicon insulated gate bipolar transistor SiIGBT is not affected. Among them, the process of turning on the silicon carbide field effect transistor SiC MOSFE is about several hundred ns, and the P-type MOS tube Q1 will be turned on again.

[0058] When the silicon carbide field effect transistor SiC MOSFE is turned off, the first P-type MOS transistor Q1 remains turned on. However, since there is a circulating current from right to left in the first P-type MOS transistor Q1, the disconnection efficiency of the silicon carbide field effect transistor SiCMOSFE will be affected. Therefore, in the present disclosure, the second P-type MOS transistor Q2 is connected in anti-phase series with the first P-type MOS transistor Q1 to control the disconnection of the second P-type MOS transistor Q2 during the disconnection of the silicon carbide field effect transistor SiC MOSFE, so as to suppress the circulating current of the ground loop during the disconnection of the hybrid switch.

[0059] Therefore, if Figure 7 As shown, during the disconnection of the silicon carbide field effect transistor SiC MOSFE, the fourth driving signal is at a high level to control the second P-type MOS transistor Q2 to be disconnected briefly, so as to suppress the circulating current of the ground loop during the disconnection of the hybrid switch. After the disconnection of the silicon carbide field effect transistor SiC MOSFE is completed, the second P-type MOS transistor Q2 is turned on again. The disconnection process of the second P-type MOS transistor Q2 lasts for several hundred ns.

[0060] In another embodiment, the current suppression unit may include a first device, which is a device that is in a low impedance state in a low frequency band and in a high impedance state in a high frequency band. Figure 3 As shown, the first device may be a magnetic bead R3, one end of which is connected to the fourth stray inductor L4, and the other end of which is connected to the emitter of the silicon insulated gate bipolar transistor Si IGBT. In this embodiment, the circulating inductance in the ground loop is suppressed by the first device which is in a low impedance state in the low frequency band and in a high impedance state in the high frequency band.

[0061] In the present disclosure, the driving circuit can also be processed separately, that is, two independent driving power supplies are used to control the first power switch and the second power switch respectively, fundamentally and completely disconnecting the path of the circulating current, thereby effectively suppressing the circulating current of the grounding circuit in the hybrid switch circuit. Figure 4 As shown, the first driving circuit uses the first driving power supply VCC3, the second driving circuit uses the second driving power supply VCC4, and the first driving power supply VCC3 and the second driving power supply VCC4 are independently set. That is, the ground terminal of the first driving circuit is different from the ground terminal of the second driving circuit.

[0062] In the present disclosure, the duration of the electrical signal controlling the silicon carbide field effect transistor SiC MOSFE to be in the off state can also be adjusted by detecting the junction temperature of the silicon carbide field effect transistor SiC MOSFE to improve the utilization rate of the silicon carbide field effect transistor SiC MOSFE.

[0063] In one embodiment, the hybrid switch circuit may further include a junction temperature detection device and a second control device. The junction temperature detection device is connected to another power switch other than the target power switch, and is used to detect the junction temperature of the other power switch other than the target power switch. The second control device is respectively connected to the junction temperature detection device and another drive circuit other than the target drive circuit, and is used to adjust the duration of the electrical signal in the other drive circuit for controlling the other power switch other than the target power switch to be in an off state according to the junction temperature.

[0064] By way of example, the junction temperature detection device may include a temperature detection unit, a current detection unit, and a processing unit. The temperature detection unit is used to detect the temperature of another power switch other than the target power switch; the current detection unit is used to detect the current flowing through another power switch other than the target power switch when the first power switch and the second power switch are in the on state; the processing unit is connected to the temperature detection unit and the current detection unit, and is used to determine the junction temperature of the other power switch at the end of the current driving cycle based on the temperature, the current, and the duration of the electrical signal that controls the other power switch to be in the off state during the current driving cycle.

[0065] For example, the temperature detection unit and the current detection unit are both arranged in the silicon carbide field effect transistor SiC MOSFE loop, and are used to detect the temperature and current of the silicon carbide field effect transistor SiC MOSFE. The processing unit can determine the junction temperature of the silicon carbide field effect transistor SiC MOSFE at the end of the current driving cycle by a preset calculation method according to the detected temperature, current and the duration of the electrical signal that controls another power switch to be in an off state during the current driving cycle.

[0066] The junction temperature may be calculated by using a method for calculating the junction temperature in related technologies, and the present disclosure does not impose any limitation on this.

[0067] After calculating the junction temperature of the silicon carbide field effect transistor SiC MOSFE at the end of the current driving cycle, the duration of the electrical signal controlling the silicon carbide field effect transistor SiC MOSFE to be in an off state in the next driving cycle can be adjusted according to the calculated junction temperature.

[0068] It should be understood that the electrical signal that controls the silicon carbide field effect transistor SiC MOSFE to be in the off state is a low-level signal, that is, according to the junction temperature of the silicon carbide field effect transistor SiC MOSFE at the end of the current driving cycle, the duration of the low level in the driving signal driving the silicon carbide field effect transistor SiC MOSFE in the next driving cycle is adjusted.

[0069] In one possible embodiment, the second control device is connected to the processing unit and is used to reduce the duration of the electrical signal that controls the other power switch to be in the off state in the next drive cycle if the junction temperature of the other power switch is less than the preset junction temperature threshold at the end of the current drive cycle, and to increase the duration of the electrical signal that controls the other power switch to be in the off state in the next drive cycle if the junction temperature of the other power switch is greater than the preset junction temperature threshold at the end of the current drive cycle.

[0070] For example, if the junction temperature of the silicon carbide field effect transistor SiC MOSFE is less than the preset junction temperature threshold at the end of the current driving cycle, the duration of the low level in the driving signal of the silicon carbide field effect transistor SiC MOSFE in the next driving cycle is reduced to extend the conduction time of the silicon carbide field effect transistor SiC MOSFE, improve the utilization rate of the silicon carbide field effect transistor SiCMOSFE, thereby reducing the number of silicon carbide field effect transistors SiC MOSFE used, and can fully reduce costs. If the junction temperature of the silicon carbide field effect transistor SiC MOSFE is greater than the preset junction temperature threshold at the end of the current driving cycle, the duration of the low level in the driving signal of the silicon carbide field effect transistor SiC MOSFE in the next driving cycle is increased to reduce the conduction time of the silicon carbide field effect transistor SiC MOSFE, that is, reduce the junction temperature rate of the silicon carbide field effect transistor SiC MOSFE, and extend the service life of the silicon carbide field effect transistor SiC MOSFE.

[0071] It should be understood that in the present disclosure, proportional regulation, exponential regulation, etc. can be used to adjust the duration of the low level in the silicon carbide field effect transistor SiC MOSFE drive signal in the next drive cycle according to the junction temperature of the silicon carbide field effect transistor SiC MOSFE at the end of the current drive cycle. The present disclosure does not make specific limitations on this.

[0072] Based on the same inventive concept, the present disclosure also provides an electric drive controller, which includes the hybrid switch circuit provided by the present disclosure.

[0073] Based on the same inventive concept, the present disclosure also provides a vehicle, including the electric drive controller provided by the present disclosure.

[0074] For example, the vehicle may be a pure electric vehicle, or a hybrid vehicle, etc.

[0075] In addition, the word "exemplary" is used herein to indicate serving as an example, instance, or diagram. Any aspect or design described as "exemplary" in this article is not necessarily understood to be advantageous compared to other aspects or designs. On the contrary, the use of the word exemplary is intended to present concepts in a specific way. As used herein, the term "or" is intended to represent an inclusive "or" rather than an exclusive "or". That is, unless otherwise specified or clear from the context, "X applies A or B" is intended to represent any one of the natural inclusive arrangements. That is, if X applies A; X applies B; or X applies both A and B, "X applies A or B" is satisfied under any of the aforementioned examples. In addition, unless otherwise specified or clearly pointed to a singular form from the context, the articles "one" and "an" as used in this application and the appended claims are generally understood to mean "one or more".

[0076] Likewise, although the present disclosure has been shown and described with respect to one or more implementations, equivalent variations and modifications will occur to those skilled in the art after reading and understanding the specification and drawings. The present disclosure includes all such modifications and variations and is limited only by the scope of the claims. In particular, with respect to the various functions performed by the components (e.g., elements, resources, etc.) described above, unless otherwise indicated, the terms used to describe such components are intended to correspond to any component (functionally equivalent) that performs the specific functions of the described components, even if the structure is not equivalent to the disclosed structure. In addition, although specific features of the present disclosure may have been disclosed with respect to only one of several implementations, such features may be combined with one or more other features of other implementations as may be desired and beneficial to any given or specific application. In addition, with respect to "including", "having", "having", "having", or variations thereof used in a specific embodiment or claim, such terms are intended to be inclusive in a manner similar to the term "comprising".

[0077] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

[0078] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A hybrid switching circuit, characterized in that: The hybrid switch circuit comprises: A first power switch and a second power switch connected in parallel, wherein the first power switch and the second power switch are of different types; A first driving circuit, wherein the first driving circuit is connected to the first power switch and is used to drive the first power switch to be turned on or off; A second driving circuit, the second driving circuit is connected to the second power switch and is used to drive the second power switch to be turned on or off; A current suppression unit, wherein the current suppression unit is arranged on a first branch in a target drive circuit, and is used to suppress a circulating current of a ground circuit in the hybrid switch circuit, wherein the first branch is a branch in the ground circuit, the target drive circuit is a drive circuit for driving a target power switch, and the target power switch is a power switch with delayed conduction between the first power switch and the second power switch.

2. The hybrid switch circuit according to claim 1, characterized in that: The current suppression unit includes a switch device; The switch device is used to be disconnected during the conduction process of another power switch other than the target power switch, so as to suppress the circulating current of the ground loop; The switch device is further configured to be turned on when the target power switch is turned on.

3. The hybrid switch circuit according to claim 2, characterized in that: The switch device includes a first P-type MOS tube, the drain of the first P-type MOS tube is connected to the emitter of the target power switch, the source of the first P-type MOS tube is grounded, and the gate of the P-type MOS tube is used to input a third drive signal for controlling the first P-type MOS tube to be turned on or off.

4. The hybrid switch circuit according to claim 3, characterized in that: The switch device also includes a second P-type MOS tube, a source of the second P-type MOS tube is connected to the source of the first P-type MOS tube, a drain of the second P-type MOS tube is grounded, and a gate of the second P-type MOS tube is used to input a fourth drive signal for controlling the second P-type MOS tube to be turned on or off.

5. The hybrid switch circuit according to claim 1, characterized in that: The current suppression unit includes a first component, which is in a low impedance state in a low frequency band and in a high impedance state in a high frequency band.

6. The hybrid switch circuit according to claim 1, characterized in that: The first driving circuit further includes a first switch, a second switch and a driving power supply, and the second driving circuit further includes a third switch, a fourth switch and a driving power supply; the driving power supply includes a first power supply and a second power supply, and the negative electrode of the first power supply is connected to the positive electrode of the second power supply; The first switch is located between the negative electrode of the second power supply and the first power switch, the second switch is located between the positive electrode of the first power supply and the first power switch, the third switch is located between the negative electrode of the second power supply and the second power switch, and the fourth switch is located between the positive electrode of the first power supply and the second power switch.

7. The hybrid switch circuit according to claim 6, characterized in that: The hybrid switch circuit further comprises: a first control device; The first control device is connected to the first switch, the second switch, the third switch and the fourth switch, respectively, and is used to control the first switch, the second switch, the third switch and the fourth switch to be turned on and off according to a preset switch timing, so that the target power switch is delayed to be turned on and / or turned off in advance.

8. The hybrid switch circuit according to any one of claims 1 to 7, characterized in that: If the switching loss of the first power switch is lower than the switching loss of the second power switch, the second power switch delays the first power switch from turning on, the target power switch is the second power switch, and the target drive circuit is the second drive circuit.

9. The hybrid switch circuit according to claim 8, characterized in that: The first power switch is a silicon carbide field effect transistor, and / or the second power switch is a silicon insulated gate bipolar transistor.

10. The hybrid switch circuit according to any one of claims 1 to 7, characterized in that: A ground terminal of the first driving circuit is different from a ground terminal of the second driving circuit.

11. The hybrid switch circuit according to any one of claims 1 to 7, characterized in that: The hybrid switch circuit further comprises: a junction temperature detection device and a second control device; The junction temperature detection device is connected to another power switch other than the target power switch, and is used to detect the junction temperature of the other power switch other than the target power switch; The second control device is respectively connected to the junction temperature detection device and another drive circuit outside the target drive circuit, and is used to adjust the duration of the electrical signal in the other drive circuit used to control another power switch outside the target power switch to be in an off state according to the junction temperature.

12. The hybrid switch circuit according to claim 11, characterized in that: The junction temperature detection device includes a temperature detection unit, a current detection unit and a processing unit; The temperature detection unit is used to detect the temperature of another power switch other than the target power switch; The current detection unit is used to detect the current flowing through another power switch other than the target power switch when the first power switch and the second power switch are in the on state; The processing unit is connected to the temperature detection unit and the current detection unit, and is used to determine the junction temperature of the other power switch at the end of the current driving cycle based on the temperature, the current and the duration of the electrical signal that controls the other power switch to be in the off state during the current driving cycle.

13. The hybrid switch circuit according to claim 12, characterized in that: The second control device is connected to the processing unit and is used to reduce the duration of the electrical signal that controls the other power switch to be in the off state in the next driving cycle if the junction temperature of the other power switch is less than the preset junction temperature threshold at the end of the current driving cycle, and to increase the duration of the electrical signal that controls the other power switch to be in the off state in the next driving cycle if the junction temperature of the other power switch is greater than the preset junction temperature threshold at the end of the current driving cycle.

14. An electric drive controller, characterized in that: The hybrid switch circuit comprises the hybrid switch circuit as claimed in any one of claims 1 to 13.

15. A vehicle, characterized in that: The vehicle includes the electric drive controller as claimed in claim 14.

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