Switching transistor drive resistor circuit, power converter, and power conversion system

Abstract

The disclosure provides a kind of switch tube driving resistance circuit, power converter and power conversion system, it is related to switch tube driving technical field.The switch tube driving resistance circuit, comprising: at least two driving units;The input end of each driving unit is configured to receive the same driving signal, the output end of each driving unit is respectively connected to the control end of corresponding switch tube unit;These switch tube units are connected in parallel, and the device parameters of each driving unit and the wiring parameters of the switch tube unit connected to it are opposite to the current influence of the corresponding switch tube unit, wherein the device parameters of at least two driving units are different, and then it is beneficial to realize current sharing between each parallel switch tube unit, without selecting the switch tube unit with higher cost, the cost of parallel switch tube unit can be saved.

Description

Technical Field

[0001] This disclosure relates to the field of switching transistor driving technology, and in particular to a switching transistor driving resistor circuit, a power converter, and a power conversion system. Background Technology

[0002] When switching transistors are used in parallel, uneven current distribution can occur between them due to differences in circuit layout and wiring. This uneven current distribution can manifest as dynamic uneven current distribution for changing currents and static uneven current distribution for steady currents. This uneven current distribution can cause some switching transistors to bear greater stress and generate more heat. Since the stress and heat that switching transistors can withstand are limited, traditional solutions require selecting switching transistors with strong voltage and current handling capabilities for parallel use, which results in cost waste. Utility Model Content

[0003] In view of the above problems, this disclosure provides a switching transistor drive resistor circuit, a power converter, and a power conversion system to reduce the cost of parallel switching transistors. The specific solution is as follows:

[0004] The first aspect of this disclosure provides a switching transistor driving resistor circuit, applied to at least two switching transistor units connected in parallel; the switching transistor driving resistor circuit includes: at least two driving units; wherein...

[0005] The input terminals of each of the aforementioned drive units are configured to receive the same drive signal;

[0006] The output terminal of each drive unit is connected to the control terminal of the corresponding switch unit.

[0007] The device parameters of each driving unit and the wiring parameters of the switching transistor unit to which they are connected have opposite effects on the current of the corresponding switching transistor unit; there are differences between the device parameters of at least two driving units.

[0008] In one possible implementation, the correspondence between the driving unit and the switching transistor unit includes at least one of the following:

[0009] There are at least two of the aforementioned switching transistor units that share the same driving unit;

[0010] There are at least two of the drive units connected to the same switching transistor unit.

[0011] In one possible implementation, the switching transistor units are grouped and arranged along a first direction;

[0012] Each group of switching transistor units is connected to the corresponding driving unit.

[0013] In one possible implementation, each group of the switching transistor units includes at least one of the switching transistor units;

[0014] In any group of the switching transistor units, when the number of the switching transistor units is greater than 1, each of the switching transistor units is arranged along the second direction and connected to the same driving unit.

[0015] In one possible implementation, among the drive units that connect the same switching transistor unit, at least one drive unit is connected in series with a corresponding switch.

[0016] In one possible implementation, each of the drive units connected to the same switching transistor unit is connected in series with a corresponding switch, and the device parameters are different.

[0017] In one possible implementation, the drive units connected to the same switching transistor unit are:

[0018] When any one of the voltage, current, and temperature of the connected switching transistor unit is greater than or less than the corresponding threshold, the equivalent impedance of the connected transistor will be different.

[0019] In one possible implementation, the drive units connected to the same switching transistor unit are:

[0020] When the voltage or current of the connected switching transistor unit is greater than the corresponding threshold, the connected equivalent impedance exhibits at least two levels of change.

[0021] In one possible implementation, the driving unit includes: a first resistor, a second resistor, a third resistor, a fourth resistor, a diode, and a first capacitor;

[0022] The first resistor is connected in series with the diode, and the branch after series connection is connected in parallel with the second resistor. The two ends of the branch after parallel connection are respectively configured as the input and output terminals of the driving unit.

[0023] The third resistor is connected in series with the first capacitor, and the branch formed by the series connection is connected in parallel with the fourth resistor. The branch formed by the parallel connection is connected between the control terminal and the output terminal of the corresponding switching transistor unit.

[0024] In one possible implementation, different device parameters include at least one of the following:

[0025] The resistance value of the first resistor;

[0026] The resistance value of the second resistor;

[0027] The direction of the diode;

[0028] The resistance value of the third resistor;

[0029] The capacitance value of the first capacitor.

[0030] In one possible implementation, the driving unit further includes a second capacitor; the second capacitor is connected in parallel with the second resistor.

[0031] A second aspect of this disclosure provides a power converter, comprising: a main circuit and a drive circuit; wherein,

[0032] The main circuit includes at least one switching transistor branch, and the switching transistor branch includes two switching transistor units connected in parallel.

[0033] Each of the switching transistor units in the switching transistor branch receives the driving signal output by the driving circuit through the switching transistor driving resistor circuit as described in the first aspect or any implementation thereof.

[0034] In one possible implementation, the switching unit is a switching transistor; each of the switching transistors is integrated within a switching transistor module or is independent.

[0035] Alternatively, the switching unit may be a switching module comprising at least two parallel switching transistors.

[0036] In one possible implementation, the main circuit includes at least one of a DC / DC converter circuit and a DC / AC converter circuit.

[0037] A third aspect of this disclosure provides a power conversion system, comprising: a control system and at least one power converter as described in the second aspect or any implementation thereof; wherein...

[0038] The output terminal of the control system is connected to the input terminal of the drive circuit in the power converter.

[0039] The switching transistor drive resistor circuit provided by this disclosure, using the above technical solution, includes: at least two drive units; the input terminal of each drive unit is configured to receive the same drive signal, and the output terminal of each drive unit is respectively connected to the control terminal of the corresponding switching transistor unit; these switching transistor units are connected in parallel, and the device parameters of each drive unit and the wiring parameters of the connected switching transistor unit have opposite effects on the current of the corresponding switching transistor unit; wherein the device parameters of at least two drive units are different, which is beneficial to achieve current sharing among the parallel switching transistor units, eliminating the need to select high-cost switching transistor units and saving the cost of parallel switching transistor units. Attached Figure Description

[0040] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0041] Figure 1 This is a schematic diagram of a circuit for driving resistors of a parallel switching transistor unit provided in an embodiment of this disclosure.

[0042] Figure 2 This is another schematic diagram of the switching transistor drive resistor circuit connected to the parallel switching transistor unit provided in the embodiments of this disclosure.

[0043] Figure 3 This is another schematic diagram of the switching transistor drive resistor circuit connected to the parallel switching transistor unit provided in the embodiments of this disclosure.

[0044] Figure 4 This is another schematic diagram of the switching transistor drive resistor circuit connected to the parallel switching transistor unit provided in the embodiments of this disclosure.

[0045] Figure 5 This is another schematic diagram of the switching transistor drive resistor circuit connected to the parallel switching transistor unit provided in the embodiments of this disclosure.

[0046] Figure 6 A circuit diagram of a driving unit in a switch-driven resistor circuit provided in this embodiment of the present disclosure;

[0047] Figure 7 A schematic diagram of a power converter provided in an embodiment of this disclosure;

[0048] Figure 8 A schematic diagram of the main circuit and the switching transistor drive resistor circuit in a power converter provided in an embodiment of this disclosure;

[0049] Figure 9 This is another schematic diagram of the main circuit and the switching transistor drive resistor circuit in the power converter provided in the embodiments of this disclosure;

[0050] Figure 10 This is another schematic diagram of the main circuit and the switching transistor drive resistor circuit in the power converter provided in the embodiments of this disclosure;

[0051] Figure 11 This is another schematic diagram of the main circuit and the switching transistor drive resistor circuit in the power converter provided in the embodiments of this disclosure. Detailed Implementation

[0052] The embodiments of this disclosure are described below with reference to the accompanying drawings. The terminology used in the Description of Embodiments section of this disclosure is for illustrative purposes only and is not intended to limit the scope of this disclosure.

[0053] The embodiments of this disclosure are described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure. Those skilled in the art will understand that with the development of technology and the emergence of new scenarios, the technical solutions provided by the embodiments of this disclosure are also applicable to similar technical problems.

[0054] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same properties in the description of embodiments of this disclosure. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements but may include other elements not expressly listed or inherent to those processes, methods, products, or apparatuses.

[0055] In traditional solutions, when switching transistors are used in parallel, it is generally assumed that the transistors have similar characteristics and are placed in close proximity. Therefore, when selecting the driving resistors and capacitors, devices with the same parameters are chosen. However, in reality, due to different wiring, dynamic and static current imbalances can exist between the parallel switching transistors. Since the stress and heat that switching transistors can withstand are limited, traditional solutions require selecting switching transistors with strong voltage and current handling capabilities for parallel use, resulting in cost waste.

[0056] Based on this, the present disclosure provides a switching transistor driving resistor circuit to reduce the cost of parallel switching transistors. The specific solution is as follows:

[0057] like Figure 1 As shown, the switch-driven resistor circuit is applied to at least two switch units connected in parallel. Figure 1 (The example shown uses two switching transistor units S1 and S2); the switching transistor drive resistor circuit includes: at least two drive units ( Figure 1 (Taking two drive units 1 and 2 as examples for demonstration) 101; where:

[0058] Each drive unit 101 has its input terminal configured to receive the same drive signal (PWM as shown in the figure). This drive signal can originate from the controller of the device where each switching unit is located. The controller outputs a corresponding control signal to the drive circuit, which then outputs the drive signal. The control signal can be a PWM (Pulse Width Modulation) signal, in which case the drive signal has the same frequency as the PWM signal. Each parallel-connected switching unit can share the same drive circuit and receive the same drive signal, or it can be equipped with its own corresponding drive circuit and receive the same drive signal through its own drive circuit; this depends on the specific application environment and is within the scope of this disclosure.

[0059] The output terminal of each drive unit 101 is connected to the control terminal of the corresponding switching transistor unit; as shown in the figure, the output terminal of drive unit 1 is connected to the control terminal of switching transistor unit S1, and the output terminal of drive unit 2 is connected to the control terminal of switching transistor unit S2; the same logic applies when there are more switching transistor units and drive units 101, and some specific examples are given below.

[0060] The device parameters of each drive unit 101 correspond to the wiring parameters of the switching transistor unit it is connected to. Their effects on the current of the corresponding switching transistor unit are opposite, and at least two drive units 101 have different device parameters. These wiring parameters may include: the PCB (Printed Circuit Board) trace length and cross-sectional area of ​​the PCB trace connecting the switching transistor unit to the parallel connection point, the busbar connection position when using a busbar for connection, and the contact resistance of the connection point, etc. Parameters that can affect the current sharing of each switching transistor unit are all within the protection scope of this disclosure; these are only some optional examples. These device parameters may include the equivalent impedance of the drive unit 101, and parameters that can affect the equivalent impedance of the drive unit 101 can be of various types, such as the resistance value of a resistor, the capacitance value of a capacitor, etc., which are not limited here and can be determined according to the structure of the drive unit 101. Figure 1Taking the two parallel switching transistor units shown as examples, the correspondence between device parameters and wiring parameters can be specifically as follows: For switching transistor units with longer PCB traces, the equivalent impedance of the connected drive unit 101 is smaller, resulting in faster switching speeds and compensating for the lower current draw caused by the longer PCB trace length; for switching transistor units with larger PCB trace cross-sectional areas, the equivalent impedance of the connected drive unit 101 is larger, resulting in slower switching speeds and compensating for the higher current draw caused by the larger PCB trace cross-sectional area; when the busbars are connected in parallel, the equivalent impedance of the connected drive unit 101 is smaller for switching transistor units with farther busbar connection locations, resulting in faster switching speeds and compensating for the lower current draw caused by the farther busbar connection locations; for switching transistor units with higher contact resistance at connection points, such as those with uneven pressure or oxidation of the bolts at the corresponding connection points, the equivalent impedance of the connected drive unit 101 is smaller, resulting in faster switching speeds and compensating for the lower current draw caused by the higher contact resistance at the connection points.

[0061] In practical applications, the device parameters of each parallel switching transistor unit can be matched according to the specific structure of the driving unit 101 while keeping a single variable. Specifically, while ensuring that the parameters affecting the current sharing characteristics of the switching transistor units are consistent, such as the threshold voltage Vgeth, on-state voltage drop Vcesat, and diode D voltage drop Vf of each parallel switching transistor unit, the current sharing of the parallel switching transistor units under different device parameters can be tested, thereby obtaining the corresponding device parameters that enable each parallel switching transistor unit to achieve current sharing.

[0062] by Figure 1 Taking the two parallel switching transistor units shown as an example, the two driving units 101, namely driving unit 1 and driving unit 2, are driven by the same driving signal. The device parameters of driving unit 1 and driving unit 2 are designed to be different. Therefore, by using different driving units 101, the switching speeds of the two switching transistor units S1 and S2 are forced to be different, so as to compensate for the problem of uneven current of the switching transistor units caused by the layout.

[0063] Figure 2Taking three parallel switching transistor units as an example, the three driving units 101, namely driving unit 1, driving unit 2, and driving unit 3, are driven by the same driving signal. Assuming that the layout of switching transistor units S1 and S2 on both sides is symmetrical about switching transistor unit S3, and that the wiring parameters of switching transistor units S1 and S2 are identical, then the device parameters of driving unit 1 and driving unit 2 can be set to be exactly the same, while the device parameters of driving unit 3 are different from those of driving units 1 and 2. That is, when the number of parallel switching transistor units is greater than two, current sharing can be achieved by designing different device parameters for each driving unit 101, or by using the same device parameters for some driving units 101 and different device parameters for others, depending on the specific layout of the switching transistor units. For a larger number of parallel switching transistor units, the driving unit 101 can also be designed in this way.

[0064] The switching transistor drive resistor circuit provided in this embodiment, for parallel-connected switching transistor units, achieves different switching speeds by adapting drive units with different device parameters. It can perform current sharing compensation for both changing and stable currents, effectively reducing the degree of dynamic and static current imbalance, thereby achieving dynamic and static current sharing. Therefore, there is no need to select more expensive switching transistor units, saving on the cost of parallel switching transistor units.

[0065] In practical applications, the switching unit can be a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), or other switching components. The wiring parameters of each parallel switching component are different due to the layout of its PCB (Printed Circuit Board). In this case, current sharing among the parallel switching components can be achieved by using a driving unit 101 corresponding to its own wiring parameters.

[0066] The switching component can be a switching transistor module, which includes multiple wafers. Each wafer is processed to form a corresponding switching transistor, and the switching transistors are connected in parallel. The layout and wiring inside the switching transistor module result in different wiring parameters for each parallel switching transistor. In this case, each switching transistor can be used as a switching transistor unit, and current sharing among the parallel switching transistors can be achieved by using a driving unit 101 corresponding to its own wiring parameters.

[0067] In practical applications, the correspondence between the driving unit 101 and the switching unit in this switching transistor driving resistor circuit is not limited to... Figure 1 and Figure 2 The one-to-one correspondence shown may also include at least one of the following: there are at least two switching transistor units that share the same driving unit 101; and there are at least two driving units 101 that are connected to the same switching transistor unit.

[0068] Figure 3 The example shown uses a switching transistor unit, where each switching transistor module comprises four wafers (wafers 1 to 4 as shown in the figure). The switching transistors fabricated on wafers 1 to 4 are connected in parallel (the PCB traces for the parallel connection are not shown in the figure). For driving the switching transistors fabricated on wafers 1 to 4, each pair of wafers can share the same driving unit 101. For example, wafers 1 and 2 on the left side of the figure share driving unit 1, and wafers 3 and 4 on the right side share driving unit 2. In practical applications, a larger number of switching transistor units can also share the same driving unit 101, which will not be illustrated further.

[0069] Figure 4 The example shown uses two switching transistor units (S1 and S2 as shown in the figure) connected in parallel. Each switching transistor unit is connected to two drive units 101. For example, switching transistor unit S1 is connected to drive unit 1 and drive unit 1', and switching transistor unit S2 is connected to drive unit 2 and drive unit 2'. In practical applications, a larger number of drive units 101 can also be connected to the same switching transistor unit.

[0070] Figure 5 The example shown uses four switching transistor units (IGBT1 to 4 as shown in the figure) connected in parallel (the PCB traces for parallel connection are not shown in the figure). Each pair of switching transistor units shares the same two drive units 101. For example, the control terminals of IGBT1 and IGBT2 are both connected to the output terminals of drive unit 1 and drive unit 1', and the control terminals of IGBT3 and IGBT4 are both connected to the output terminals of drive unit 2 and drive unit 2'. In practical applications, a larger number of drive units 101 can also be used to connect the same switching transistor units.

[0071] In one example, when there are a large number of parallel switching transistor units, the switching transistor units can be arranged in groups along a first direction, and each group of switching transistor units can be connected to a corresponding drive unit 101. Figure 1 , Figure 2 and Figure 4 Each example uses a separate switching transistor unit as a group for demonstration. Figure 3 and Figure 5The examples all use two switching transistor units as a group for demonstration. Figures 1 to 3 Each group of switching transistor units is connected to a corresponding drive unit 101. Figure 4 and Figure 5 Each group of switching transistor units is connected to two corresponding drive units 101. The first direction can be... Figures 1 to 5 The horizontal direction shown, but not limited to it.

[0072] Moreover, each group of switching transistor units includes at least one switching transistor unit; Figure 1 , Figure 2 and Figure 4 The examples all use the example of each group of switching transistor units consisting of one switching transistor unit. Figure 3 and Figure 5 The examples illustrate this by assuming each group of switching transistor units comprises two switching transistor units. In any group of switching transistor units, when the number of switching transistor units is greater than one, the switching transistor units are arranged along a second direction and connected to the same drive unit 101. This second direction can be... Figure 3 and Figure 5 The vertical direction shown is not limited to this.

[0073] by Figure 3 Taking the example shown, within the corresponding switching transistor module, the switching transistors supported by wafers 1 to 4 are connected in parallel. The set of wafers 1 and 2 on the left are driven by the same driving unit 1, and the set of wafers 3 and 4 on the right are driven by the same driving unit 2. The number of wafers in the set on the left can be greater than or equal to 1, and the number of wafers in the set on the right can also be greater than or equal to 1. The number of sets obtained by horizontally arranging the wafers can be greater than or equal to 2, and the corresponding driving units 101 also need to be increased synchronously. For each set of horizontally arranged wafers, different driving units 101 are used to control them to achieve current sharing.

[0074] In one example, it can be configured such that among the drive units 101 connected to the same switching transistor unit, at least one drive unit 101 is connected in series with a corresponding switch. For example... Figure 5 As shown, drive unit 1 is connected in series with switch K1, and drive unit 2 is connected in series with switch K2. If switch K1 is open, the control terminals of IGBT 1 and 2 can only be connected to drive unit 1', and the equivalent impedance of the drive resistor is relatively large. If switch K1 is closed, the control terminals of IGBT 1 and 2 are connected to drive unit 1 and drive unit 1', and the equivalent impedance of the drive resistor is the parallel resistance of the two drive units, which is smaller than the equivalent impedance when switch K1 is open.

[0075] In practical applications, the following configuration can be used: each drive unit 101 connected to the same switching transistor unit is connected in series with a corresponding switch, and the device parameters are different. For example... Figure 4 As shown, drive unit 1 is connected in series with switch K1, drive unit 1' is connected in series with switch K1', and the two series branches are connected in parallel; drive unit 2 is connected in series with switch K2, drive unit 2' is connected in series with switch K2', and the two series branches are connected in parallel. Taking drive unit 1 and drive unit 1' as examples, when switch K1 is closed and switch K1' is open, the control terminal of switch transistor unit S1 receives the drive signal through drive unit 1; when switch K1 is open and switch K1' is closed, the control terminal of switch transistor unit S1 receives the drive signal through drive unit 1'. The device parameters of drive unit 1 and drive unit 1' are different, therefore, different equivalent impedances of drive resistors will be connected when different switches are closed.

[0076] The equivalent impedance of the drive resistor can be determined according to the working state of the switching transistor unit. For example, for each drive unit 101 connected to the same switching transistor unit, the equivalent impedance will be different if any one of the voltage, current and temperature of the connected switching transistor unit is greater than or less than the corresponding threshold.

[0077] by Figure 4 Taking the example shown, when both voltage and current are less than the corresponding threshold, switching transistor unit S1 can be connected to drive unit 1, and switching transistor unit S2 can be connected to drive unit 2. The device parameters of drive units 1 and 2 can be the same or different. For special scenarios, such as when the devices where each switching transistor unit is located experience low-voltage breakdown and phase-to-phase short circuit, the voltage and current conditions can be used to determine the connection. For example, if the voltage or current is greater than the corresponding threshold, switching transistor unit S1 can be connected to drive unit 1', and switching transistor unit S2 can be connected to drive unit 2'. The device parameters of drive units 1' and 2' can be different to achieve current sharing of parallel switching transistor units in high-current application scenarios.

[0078] In addition, for each drive unit 101 connected to the same switching transistor unit, it can be set that when the voltage or current of the connected switching transistor unit is greater than the corresponding threshold, the equivalent impedance of the connected unit has at least two levels of change.

[0079] Still with Figure 4Taking the example shown, in high-current applications, based on the same driving signal, each parallel switching transistor unit can be configured to first achieve the first-stage turn-on with a larger equivalent impedance, and then achieve the second-stage turn-on with a smaller equivalent impedance, thus achieving graded turn-on. The principle of graded turn-off is similar, and details can be found in related technologies. The equivalent impedance can be achieved by connecting different driving units 101 in the above embodiment. In practical applications, for graded turn-off and graded turn-on, such as for high-voltage and high-current scenarios like high-voltage protection, low-voltage protection, phase-to-phase short circuit protection, and overcurrent protection, and for cases with a large number of parallel driving units, different equivalent impedances of the driving resistors can be switched, and multiple different switching schemes can be set. These will not be elaborated on further, and are all within the protection scope of this disclosure.

[0080] Furthermore, for each drive unit 101 connected to the same switching transistor unit, the equivalent impedance can be different depending on whether the temperature of the connected switching transistor unit is above or below a corresponding threshold. For example, when the temperature of the switching transistor unit is high, a smaller equivalent impedance can be achieved by connecting the drive unit 101, thereby reducing the switching time of the switching transistor unit, reducing its switching losses, and improving the circuit's conversion efficiency. The temperature of the switching transistor unit can be detected using an NTC (negative temperature coefficient) resistor on the heat sink where the switching transistor unit is located. Multiple NTC resistors can be installed on the heat sink; details can be found in relevant technologies and will not be elaborated here.

[0081] This embodiment addresses the issue of inconsistent dynamic and static currents in switching transistor units caused by layout and other factors. By matching different equivalent impedances of drive resistors, the current flowing through parallel switching transistor units becomes similar, thus eliminating the need to select switching transistor units with larger current capabilities and saving costs.

[0082] Based on the above embodiments, this embodiment provides an example of the specific implementation of the switch driving resistor circuit. For example, its driving unit 101 may include... Figure 6 The following components are shown: first resistor R1, second resistor R2, third resistor R3, fourth resistor R4, diode D, and first capacitor C1; wherein:

[0083] The first resistor R1 is connected in series with the diode D. The branch after series connection is connected in parallel with the second resistor R2. The two ends of the branch after parallel connection are respectively configured as the input and output terminals of the drive unit 101. The input terminal of the drive unit 101 is used to receive the drive signal (PWM as shown in the figure), and the output terminal of the drive unit 101 is used to connect to the corresponding switching transistor unit (S1 as shown in the figure).

[0084] The third resistor R3 is connected in series with the first capacitor C1. The branch formed by the series connection is connected in parallel with the fourth resistor R4. The branch formed by the parallel connection is connected between the control terminal and the output terminal of the corresponding switching transistor unit.

[0085] If the drive signal is high, the diode D will be reverse-biased and cut off. The series voltage of the second resistor R2 and the fourth resistor R4 constitutes the threshold voltage Vgeth of the switching unit. If the drive signal is low, the diode D will be turned on. At this time, the threshold voltage Vgeth of the switching unit is equal to the series voltage of the parallel equivalent resistance of the second resistor R2 and the first resistor R1 and the fourth resistor R4.

[0086] In practical applications, different device parameters may include at least one of the following: the resistance value of the first resistor R1, the resistance value of the second resistor R2, the orientation of the diode D, the resistance value of the third resistor R3, and the capacitance value of the first capacitor C1. That is, to modify the switching speed of the drive unit 101, one can modify the value of the first resistor R1 or the second resistor R2, or modify the orientation of the diode D, or modify the resistance value of the third resistor R3 and the capacitance value of the first capacitor C1, or a combination of these methods. No limitation is made here; the choice depends on the specific application environment, and all are within the scope of this disclosure.

[0087] In another example, the drive unit 101 may further include a second capacitor C2; the second capacitor C2 is connected in parallel with the second resistor R2, and the presence of the second capacitor C2 can speed up the turn-on process during turn-on control.

[0088] In practical applications, the drive unit 101 can also be implemented in other ways. Figure 6 The above is only one optional example. Other structures in the related technology can also be selected, as long as the device parameters of each drive unit 101 correspond to the wiring parameters of the switch tube unit to which it is connected, and all are within the protection scope of this disclosure.

[0089] Another embodiment of this disclosure also provides a power converter, such as Figure 7 As shown, it includes: a main circuit 10 and a drive circuit 20; wherein, the main circuit 10 includes at least one switching transistor branch, the switching transistor branch including two switching transistor units connected in parallel; and, each switching transistor unit in the switching transistor branch receives the drive signal output by the drive circuit 20 through the switching transistor drive resistor circuit as described in any of the above embodiments.

[0090] The specific structure and working principle of the switching transistor driving resistor circuit can be found in the above embodiments, and will not be repeated here.

[0091] Each switching transistor unit receives its corresponding drive signal (PWM as shown in the figure) through the corresponding drive unit in its switching transistor drive resistor circuit. When the number of switching transistor branches in the main circuit 10 is greater than one, the number of drive signals is also greater than one, and each switching transistor branch receives its corresponding drive signal. This drive signal can be the signal obtained after the control signal output by the controller 30 passes through the drive circuit 20. In practical applications, the controller 30 can be integrated into the power converter or placed outside the power converter; this is not limited here and depends on the specific application environment.

[0092] As described in the above embodiments, the switching unit may refer to a switching transistor; each switching transistor may be integrated into a switching transistor module or may be independent; or, the switching unit may refer to a switching transistor module including at least two parallel switching transistors.

[0093] In practical applications, the main circuit 10 may include at least one of a DC / DC conversion circuit and a DC / AC conversion circuit.

[0094] Figure 8 The main circuit 10 includes a DC / DC converter circuit, and the DC / DC converter circuit adopts a Boost topology as an example for demonstration. In the Boost topology, two switching transistor units Q1 and Q2 are set in parallel between the positive and negative transmission branches. Switching transistor unit Q1 receives the drive signal (PWM as shown in the figure) through drive unit 1, and switching transistor unit Q2 receives the drive signal through drive unit 2. Figure 9 The main circuit 10 includes a DC / AC conversion circuit, and the DC / AC conversion circuit adopts a TNPC (T-Neutral Point Clamped) topology as an example for demonstration. In this TNPC topology, each switching transistor branch is implemented by two parallel-connected switching transistor units. Specifically, switching transistor units Q1 and Q2 are connected in parallel, switching transistor units Q3 and Q4 are connected in parallel, switching transistor units Q5 and Q6 are connected in parallel, and switching transistor units Q7 and Q8 are connected in parallel. Each switching transistor unit receives the corresponding driving signal through the corresponding driving unit (one of the driving units 1 to 8 shown in the figure). The parallel-connected switching transistor units can receive the same driving signal or the same driving signal. Figure 10 The example shown is that the main circuit 10 includes a DC / AC conversion circuit, and the DC / AC conversion circuit adopts an INPC (I-Neutral Point Clamped) topology. Figure 11The main circuit 10 includes a DC / AC conversion circuit, and the DC / AC conversion circuit adopts an ANPC (Active Neutral Point Clamped) topology as an example for demonstration. For specific topology structures, please refer to related technologies. The difference is that in this embodiment, parallel switching transistor units are used to implement the corresponding switching transistors in the related technologies, and the parallel switching transistor units are connected to different driving units.

[0095] by Figure 9 Taking the example shown, switching transistor units Q1 and Q2 are connected in parallel to form the upper half-bridge arm branch, and switching transistor units Q3 and Q4 are connected in parallel to form the lower half-bridge arm branch. Since the two half-bridge arm branches are corresponding and have different heat dissipation conditions, the drive units 1 to 4 can be configured to have different device parameters in each pair, thereby maximizing current carrying capacity and heat utilization. The drive unit configurations for switching transistor units Q5 to Q8 can be based on the same principle, and various combinations can be arranged when multiple transistors are used in parallel. In practical applications, the number of switching transistor units connected in parallel in each switching transistor branch is not limited. Moreover, only some examples of optional topologies are given here; other power conversion topologies are also within the scope of protection of this disclosure.

[0096] The power converter provided in this embodiment, by matching a suitable drive unit to the parallel switching transistor units, makes the current flowing through the parallel switching transistor units similar, thereby eliminating the need to select switching transistor units with larger current capabilities and saving costs.

[0097] Another embodiment of this disclosure provides a power conversion system, including: a control system and at least one power converter; wherein the output terminal of the control system is connected to the input terminal of the drive circuit in the power converter, and the structure and principle of the power converter can be referred to the above embodiments, and will not be repeated here.

[0098] In practical applications, if the power conversion system includes only one power converter, the control system can be located inside the power converter, i.e., Figure 7 The controller 30 shown is an example; alternatively, the control system may be located outside the power converter, depending on the specific application environment, and all are within the scope of protection of this disclosure.

[0099] If the power conversion system includes multiple power converters, then each power converter can be as follows: Figure 7 As shown, each power converter includes a corresponding controller 30. In this case, the control system includes each controller 30, and each controller 30 can be connected in communication. Alternatively, each power converter may not have a corresponding controller. In this case, the control system can be used to control the operation of each power converter.

[0100] Furthermore, this embodiment does not limit the main circuit structure of the power converter; for example, when the power conversion system includes only one power converter, its main circuit may include a DC / DC conversion circuit, a DC / AC conversion circuit, or both a DC / AC conversion circuit and at least one DC / DC conversion circuit connected to its DC side. When the power conversion system includes multiple power converters, there may be at least two power converters with the same main circuit, and at least one side of them may be connected in parallel; for example, multiple power converters whose main circuit includes a DC / DC conversion circuit may have one side connected to a corresponding DC power supply, and the other side connected in parallel to the DC side of a power converter whose main circuit includes a DC / AC conversion circuit. The specific application environment can be considered, and all are within the scope of protection of this disclosure.

[0101] The power conversion system provided in this embodiment, by employing the power converter provided in the above embodiment, can match a suitable drive unit for the parallel switching transistor units, so that the current flowing through the parallel switching transistor units is similar, thereby eliminating the need to select a switching transistor unit with a larger current capability and saving costs.

[0102] Similar or identical parts between the various embodiments in this specification can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the description of the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0103] The features described above regarding the disclosed embodiments can be substituted or combined with each other to enable those skilled in the art to implement or use this disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A switching transistor driving resistor circuit, characterized in that, The circuit is applied to at least two parallel-connected switching transistor units; the switching transistor drive resistor circuit includes: at least two drive units; wherein... The input terminals of each of the aforementioned drive units are configured to receive the same drive signal; The output terminal of each drive unit is connected to the control terminal of the corresponding switch unit. The device parameters of each driving unit and the wiring parameters of the switching transistor unit to which they are connected have opposite effects on the current of the corresponding switching transistor unit; there are differences between the device parameters of at least two driving units.

2. The switching transistor driving resistor circuit according to claim 1, characterized in that, The correspondence between the driving unit and the switching transistor unit includes at least one of the following: There are at least two of the aforementioned switching transistor units that share the same driving unit; There are at least two of the drive units connected to the same switching transistor unit.

3. The switching transistor driving resistor circuit according to claim 1, characterized in that, Each of the aforementioned switching transistor units is arranged in groups along the first direction; Each group of switching transistor units is connected to the corresponding driving unit.

4. The switching transistor driving resistor circuit according to claim 3, characterized in that, Each group of the switching transistor units includes at least one of the switching transistor units; In any group of the switching transistor units, when the number of the switching transistor units is greater than 1, each of the switching transistor units is arranged along the second direction and connected to the same driving unit.

5. The switching transistor driving resistor circuit according to claim 2, characterized in that, In each of the drive units connected to the same switching transistor unit, at least one drive unit is connected in series with a corresponding switch.

6. The switching transistor driving resistor circuit according to claim 5, characterized in that, Each of the drive units connected to the same switching transistor unit is connected in series with a corresponding switch, and the device parameters are different.

7. The switching transistor driving resistor circuit according to claim 5, characterized in that, Each of the drive units connected to the same switching transistor unit: When any one of the voltage, current, and temperature of the connected switching transistor unit is greater than or less than the corresponding threshold, the equivalent impedance of the connected transistor will be different.

8. The switching transistor driving resistor circuit according to claim 5, characterized in that, Each of the drive units connected to the same switching transistor unit: When the voltage or current of the connected switching transistor unit is greater than the corresponding threshold, the connected equivalent impedance exhibits at least two levels of change.

9. The switching transistor driving resistor circuit according to any one of claims 1 to 8, characterized in that, The driving unit includes: a first resistor, a second resistor, a third resistor, a fourth resistor, a diode, and a first capacitor; The first resistor is connected in series with the diode, and the branch after series connection is connected in parallel with the second resistor. The two ends of the branch after parallel connection are respectively configured as the input and output terminals of the driving unit. The third resistor is connected in series with the first capacitor, and the branch formed by the series connection is connected in parallel with the fourth resistor. The branch formed by the parallel connection is connected between the control terminal and the output terminal of the corresponding switching transistor unit.

10. The switching transistor driving resistor circuit according to claim 9, characterized in that, Different device parameters include at least one of the following: The resistance value of the first resistor; The resistance value of the second resistor; The direction of the diode; The resistance value of the third resistor; The capacitance value of the first capacitor.

11. The switching transistor driving resistor circuit according to claim 9, characterized in that, The driving unit further includes a second capacitor; the second capacitor is connected in parallel with the second resistor.

12. A power converter, characterized in that, include: Main circuit and drive circuit; among which, The main circuit includes at least one switching transistor branch, and the switching transistor branch includes two switching transistor units connected in parallel. Each of the switching transistor units in the switching transistor branch receives the driving signal output by the driving circuit through the switching transistor driving resistor circuit as described in any one of claims 1 to 11.

13. The power converter according to claim 12, characterized in that, The switching transistor unit is a switching transistor; each of the switching transistors may be integrated into a switching transistor module or be independent. Alternatively, the switching unit may be a switching module comprising at least two parallel switching transistors.

14. The power converter according to claim 12 or 13, characterized in that, The main circuit includes at least one of a DC / DC converter circuit and a DC / AC converter circuit.

15. A power conversion system, characterized in that, include: The control system and at least one power converter as described in any one of claims 12 to 14; wherein, The output terminal of the control system is connected to the input terminal of the drive circuit in the power converter.

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