Drive module for an electric energy conversion module and photovoltaic system

Abstract

The application discloses a driving module of an electric energy conversion module and a photovoltaic system, and belongs to the technical field of power electronics. The electric energy conversion module comprises a switching tube, and an input side of the electric energy conversion module is electrically connected with a bus. The driving module comprises: a monitoring unit, which is electrically connected with the bus and is configured to detect a voltage state of the bus and generate a monitoring signal, wherein the voltage state comprises multiple voltage level states; and a driving switching circuit, which is electrically connected with the monitoring unit and the switching tube and is configured to switch a driving state in response to the monitoring signal, generate a driving signal, and transmit the driving signal to a driving end of the switching tube; wherein the driving signal is used for driving the switching tube to be turned on or turned off, and the higher the voltage level of the voltage state is, the greater the driving current formed by the driving signal at the driving end of the switching tube is. The driving current of the switching tube is adjusted to be adapted to the voltage level of the bus, so that driving strategy switching under different bus voltage states is realized, and the efficiency and safety requirements are balanced.

Description

Technical Field

[0001] This application belongs to the field of power electronics technology, and in particular relates to a drive module and photovoltaic system based on a power conversion module. Background Technology

[0002] In photovoltaic (PV) systems, the output voltage of PV modules fluctuates with changes in factors such as light intensity and ambient temperature. This fluctuation directly affects the DC-side voltage of the power conversion modules within the system, such as the DC bus voltage and the DC input voltage. The power conversion modules are driven by power switching transistors.

[0003] Traditional, single, and fixed drive control strategies cannot simultaneously optimize the losses and stress of power switches across the entire DC voltage range. Optimization for high-voltage conditions, such as reducing the switching frequency, leads to excessive conduction losses at low voltages; conversely, optimization for low-voltage conditions, such as increasing the switching frequency, results in excessive switching losses and stress at high voltages, impacting efficiency and safety. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a drive module for a power conversion module and a photovoltaic system, which adjusts the drive current formed at the drive terminal of the switching transistor by the drive signal to adapt it to the bus voltage level, thereby realizing the switching of drive strategies under different bus voltage conditions and balancing efficiency and safety requirements.

[0005] In a first aspect, this application provides a drive module for a power conversion module. The power conversion module includes a switching transistor, and the input side of the power conversion module is electrically connected to a bus. The drive module includes: The monitoring unit is electrically connected to the bus and is configured to detect the voltage status of the bus and generate monitoring signals, including various voltage levels. The drive switching circuit is electrically connected to the monitoring unit and the switching transistor, and is configured to switch the drive state in response to the monitoring signal to generate a drive signal and transmit the drive signal to the drive terminal of the switching transistor. The drive signal is used to drive the switching transistor to turn on or off. The higher the voltage level of the voltage state, the greater the drive current generated by the drive signal at the drive terminal of the switching transistor.

[0006] According to one embodiment of this application, the monitoring signal includes a protection signal, which characterizes the highest voltage level among multiple voltage level states, and the monitoring unit includes: The sampling unit is electrically connected to the bus and is configured to detect the voltage of the bus and generate a detection signal; A digital controller, electrically connected to the sampling unit, is configured to generate a first overvoltage signal when the detected value of the detection signal is greater than or equal to a threshold. A comparison circuit is electrically connected to the sampling unit and configured to compare the detection signal with a threshold signal, and generate a second overvoltage signal when the signal value of the detection signal is greater than or equal to the signal value of the threshold signal. The monitoring unit is electrically connected to the digital controller, the comparison circuit and the drive switching circuit, respectively, and is configured to generate a protection signal when receiving a first overvoltage signal and / or a second overvoltage signal.

[0007] According to one embodiment of this application, the sampling unit is further configured to acquire the temperature of the switching transistor and / or the output current of the power conversion module; The driver module also includes: The reference voltage generation module is electrically connected to the sampling unit and the comparison circuit, and is configured to dynamically generate a threshold signal with a corresponding signal value based on the temperature of the switching transistor and / or the output current of the power conversion module.

[0008] According to one embodiment of this application, the reference voltage generation module includes: A microcontroller, electrically connected to the sampling unit, is configured to dynamically generate pulse width modulation signals based on the temperature of the switching transistor and / or the output current of the power conversion module. The filter circuit, whose input is electrically connected to the microcontroller, is used to filter the pulse width modulation signal. An operational amplifier has its non-inverting input electrically connected to the output of a filter circuit, and its inverting input electrically connected to its output. The output of the operational amplifier is used to output a threshold signal.

[0009] According to one embodiment of this application, the digital controller is also configured to dynamically determine a threshold based on the temperature of the switching transistor and / or the output current of the power conversion module.

[0010] According to one embodiment of this application, the comparison circuit includes: The voltage divider circuit has a first terminal for receiving a threshold signal and a second terminal for being electrically connected to a grounding node. The comparator's non-inverting input is electrically connected to the voltage divider node of the voltage divider circuit, its inverting input is used to receive the detection signal, and its output is electrically connected to the monitoring unit. The first resistor has its first end electrically connected to the non-inverting input of the comparator, and its second end electrically connected to the output of the comparator.

[0011] According to one embodiment of this application, the comparison circuit further includes: The unidirectional conducting device has its input terminal electrically connected to the second terminal of the first resistor, and its output terminal electrically connected to the output terminal of the comparator.

[0012] According to one embodiment of this application, the voltage divider circuit includes a second resistor and a third resistor. The first end of the second resistor is used to receive a threshold signal, the second end of the second resistor is electrically connected to the first end of the third resistor, and the second end of the third resistor is electrically connected to a ground node. The comparator circuit also includes: The Zener diode has its first terminal electrically connected to the first terminal of the third resistor, and its second terminal electrically connected to the second terminal of the third resistor.

[0013] According to one embodiment of this application, the drive switching circuit includes: The driver chip is used to output drive signals; The first driving resistor branch has its first end electrically connected to the driving chip and its second end electrically connected to the driving end of the switching transistor. At least one second driving resistor branch, the first end of the second driving resistor branch is electrically connected to the monitoring unit for receiving monitoring signals, and the second end of the second driving resistor branch is electrically connected to the second end of the first driving resistor branch; Among them, the higher the voltage level of the voltage state, the higher the potential of the monitoring signal.

[0014] According to one embodiment of this application, the drive switching circuit includes: The driver chip is used to output drive signals; An adjustable potentiometer has its first terminal electrically connected to a driver chip, its second terminal electrically connected to the drive terminal of a switching transistor, and its adjustment terminal electrically connected to a monitoring unit for receiving monitoring signals. The higher the voltage level of the voltage state, the smaller the resistance value of the adjustable potentiometer.

[0015] Secondly, this application provides a photovoltaic system, comprising: Photovoltaic modules are used to output DC voltage; The DC bus is electrically connected to the output terminal of the photovoltaic module. A power conversion module is electrically connected to a DC bus, and the power conversion module includes at least one switching transistor. According to the aforementioned drive module, the drive module is electrically connected to the drive terminal of the switching transistor and is used to drive the switching transistor to turn on or off.

[0016] According to the power conversion module drive module and photovoltaic system of this application, the monitoring unit detects the voltage state of the bus and generates a monitoring signal. The drive switching circuit responds to the monitoring signal to switch the drive state and adjusts the drive current formed at the drive terminal of the switching transistor to adapt it to the bus voltage level. Thus, when the bus is at a higher voltage level, the drive current is increased to speed up the switching speed of the switching transistor and reduce switching losses. When the bus is at a lower voltage level, the drive current is reduced to reduce drive losses and electromagnetic interference. This realizes the switching of drive strategies under different bus voltage states, balancing efficiency and safety requirements.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is one of the structural schematic diagrams of the driver module provided in the embodiments of this application; Figure 2 This is a second schematic diagram of the structure of the driver module provided in the embodiments of this application; Figure 3 This is a schematic diagram of the reference voltage generation module provided in an embodiment of this application; Figure 4 This is a schematic diagram of the comparison circuit provided in an embodiment of this application; Figure 5 This is a schematic diagram of the drive switching circuit provided in the embodiment of this application.

[0019] Figure label: The power conversion module 100, drive module 200, monitoring unit 210, sampling unit 211, digital controller 212, comparison circuit 213, monitoring unit 214, reference voltage generation module 215, drive switching circuit 220, and drive chip 221 are included. Detailed Implementation

[0020] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0021] In the following description, a "circuit" refers to a conductive loop consisting of at least one element or sub-circuit connected by an electrical or electromagnetic link. When an element or circuit is said to be "coupled to" or "connected to" another element, or when an element / circuit is said to be "coupled at" or "connected at" two nodes, it can be directly coupled to or connected to the other element, or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there are no intermediate elements between them.

[0022] In the description, the terms "first," "second," etc., are used to distinguish similar objects, not to describe a specific order or sequence. It should be understood that such numerical descriptors can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0023] Furthermore, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicates that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0024] Reference Figure 1 , Figure 1 This is one of the structural schematic diagrams of the driving module provided in the embodiments of this application. One embodiment of this application proposes a driving module for a power conversion module.

[0025] In this embodiment, the power conversion module 100 includes a switching transistor. The input side of the power conversion module 100 is electrically connected to the bus BUS. The drive module 200 includes a monitoring unit 210 and a drive switching circuit 220. The monitoring unit 210 is electrically connected to the bus BUS and is configured to detect the voltage state of the bus BUS and generate a monitoring signal. The voltage state includes multiple voltage levels. The drive switching circuit 220 is electrically connected to the monitoring unit 210 and the switching transistor and is configured to switch the drive state in response to the monitoring signal to generate a drive signal and transmit the drive signal to the drive terminal of the switching transistor. The drive signal is used to drive the switching transistor to turn on or off. The higher the voltage level of the voltage state, the greater the drive current formed by the drive signal at the drive terminal of the switching transistor.

[0026] In this embodiment, the drive module 200 adjusts the drive of the switching transistors in the power conversion module 100 according to the input voltage. For example, if the power conversion module 100 can be a DC / AC unit, the switches in the DC / AC unit are adjusted based on its DC-side input voltage. Alternatively, if the power conversion module 100 can be a DC / AC unit with a preceding DC-DC unit forming a larger conversion assembly, the switches in the DC / AC unit are adjusted based on the DC bus voltage between the two units. Of course, the power conversion module 100 can also be a DC / DC unit.

[0027] Voltage level status can be set according to requirements. For example, voltage level status can include high voltage status, low voltage status, or even medium voltage status. Voltage level status can be divided according to the bus voltage. By setting the boundary values ​​between each voltage level status, the voltage level status is determined based on the relationship between the bus voltage and the boundary values.

[0028] As an example, the voltage level status includes a high voltage status and a low voltage status, with a threshold value of 150V. When the monitoring unit 210 detects that the bus voltage is less than 150V, it generates a monitoring signal indicating that the voltage level status is low voltage; when the monitoring unit detects that the bus voltage is greater than or equal to 150V, it generates a monitoring signal indicating that the voltage level status is high voltage.

[0029] As another example, the monitoring signal may include bus voltage information. The monitoring unit 210 only performs voltage value sampling and feeds back the bus voltage information to the drive switching circuit 220, which then determines the voltage level status.

[0030] The switching transistor can be a power semiconductor switching device, such as an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), and its driving terminal refers to the control terminal such as the gate or base. The following explanation uses a MOSFET as an example.

[0031] The drive module generates a drive signal, corrects it according to the voltage level, and then applies it to the gate of the MOSFET. The drive signal can be generated by a controller, which generates the drive signal according to a set control strategy to control the operation of the power conversion module 100. The controller can be implemented using an MCU (Microcontroller Unit) chip; it can also be based on a DSP (Digital Signal Processor) chip or an FPGA (Field-Programmable Gate Array) chip. The controller can be implemented using a Programmable Gate Array (FPGA) or a custom-designed controller chip; this application does not limit the specific hardware implementation of the controller.

[0032] The drive switching circuit 220 can switch drive states by changing drive parameters (such as drive resistance, drive power supply amplitude, etc.) according to the monitoring signal. For example, when the bus voltage is at a lower voltage level, the drive switching circuit 220 maintains the first drive state, and the drive signal is transmitted to the drive terminal of the switching transistor with the first drive current. At this time, the drive current is small, which can meet the normal switching requirements and avoid unnecessary drive losses. When the bus voltage is at a higher voltage level, the drive switching circuit 220 switches to the second drive state, which increases the drive current formed at the drive terminal of the switching transistor. Since the voltage stress on the switching transistor increases when the voltage level increases, increasing the drive current can speed up the switching speed of the switching transistor, reduce the voltage and current overlap time during the switching process, thereby reducing switching losses and suppressing the heat generation of the switching transistor, and improving the safety and reliability of the system.

[0033] According to the power conversion module of this embodiment, the driving module detects the voltage state of the bus and generates a monitoring signal through the monitoring unit 210. The driving switching circuit 220 responds to the monitoring signal to switch the driving state and adjusts the driving current formed at the driving terminal of the switching transistor to adapt it to the bus voltage level. Thus, when the bus is at a higher voltage level, the driving current is increased to speed up the switching speed of the switching transistor and reduce switching losses. When the bus is at a lower voltage level, the driving current is reduced to reduce driving losses and electromagnetic interference. This realizes the switching of driving strategies under different bus voltage states, balancing efficiency and safety requirements.

[0034] Reference Figure 2 , Figure 2 This is a second schematic diagram of the drive module provided in the embodiments of this application. In some embodiments, the monitoring signal includes a protection signal, which represents the highest voltage level among multiple voltage level states. The monitoring unit 210 includes a sampling unit 211, a digital controller 212, a comparison circuit 213, and a monitoring unit 214. The sampling unit 211 is electrically connected to the bus and is configured to detect the voltage of the bus and generate a detection signal. The digital controller 212 is electrically connected to the sampling unit 211 and is configured to generate a first overvoltage signal when the detected value of the detection signal is greater than or equal to a threshold. The comparison circuit 213 is electrically connected to the sampling unit 211 and is configured to compare the detection signal with the threshold signal, and generate a second overvoltage signal when the signal value of the detection signal is greater than or equal to the signal value of the threshold signal. The monitoring unit 214 is electrically connected to the digital controller 212, the comparison circuit 213, and the drive switching circuit 220, and is configured to generate a protection signal when receiving the first overvoltage signal and / or the second overvoltage signal.

[0035] In this embodiment, the protection signal is used to characterize that the bus voltage is in an overvoltage state, thereby triggering the protective switching of the drive switching circuit 220. The sampling unit 211 is a circuit used to acquire analog signals such as bus voltage and convert them into electrical signals that can be processed by subsequent circuits, and may include a voltage divider resistor network and a signal conditioning circuit.

[0036] The digital controller 212 can be a microprocessor unit with data processing capabilities, such as an ARM (Advanced RISC Machine), a DSP (Digital Signal Processor), or an MCU (Microcontroller Unit). It is configured to run a software algorithm that uses a fixed or adjustable threshold as a judgment criterion. When the detected value of the signal is greater than or equal to the threshold, a first overvoltage signal is generated, achieving software protection. The digital controller 212 can sample and calculate the detected value every n microseconds (e.g., tens to hundreds of microseconds) to achieve periodic monitoring of the bus voltage.

[0037] The comparator circuit 213 may include components such as comparators, which can compare the level of the detection signal with the threshold signal in real time. When the signal value of the detection signal is greater than or equal to the signal value of the threshold signal, the output flips to generate a second overvoltage signal, thereby realizing hardware protection.

[0038] The monitoring unit 214 can be implemented using programmable logic devices such as CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array), or high-performance MCU. The monitoring unit 214 is used to comprehensively process the overvoltage signals output by the digital controller 212 and the comparator circuit 213. In the event that either or both trigger an overvoltage, it enables the protective switching of the drive switching circuit 220, achieving dual protection of hardware and software. If the software protection response is untimely or fails, the hardware comparator circuit can still act as a fast channel to trigger protection promptly; conversely, if the hardware protection circuit outputs abnormally or fails, the software protection channel can still provide redundant protection.

[0039] In some embodiments, the sampling unit 211 is further configured to acquire the temperature of the switching transistor and / or the output current of the power conversion module 100; the driving module 200 further includes a reference voltage generation module 215, which is electrically connected to the sampling unit 211 and the comparison circuit 213, and is configured to dynamically generate a threshold signal with a corresponding signal value based on the temperature of the switching transistor and / or the output current of the power conversion module.

[0040] The sampling unit 211 may include a temperature sensor (such as a thermistor, thermocouple, etc.) to detect the temperature of the switching transistor. And / or, the sampling unit 211 may include a Hall current sensor or a sampling resistor to detect the output current of the power conversion module 100. The temperature of the switching transistor and / or the output current of the power conversion module 100 can reflect the dynamic operating state of the system. The reference voltage generation module 215 adjusts the threshold signal accordingly, so that the signal value of the threshold signal can adaptively change with the temperature and / or the output current.

[0041] For example, higher temperatures or larger output currents indicate more severe switching losses. In such cases, by appropriately adjusting the threshold signal (e.g., lowering the overvoltage protection threshold), drive switching can be triggered earlier, reducing the switching frequency or increasing the drive current to decrease losses and stress. This achieves adaptive adjustment of the protection threshold based on the actual operating state of the system, avoiding the problems of fixed thresholds being too conservative (leading to frequent false triggers) or too aggressive (leading to untimely protection) under different operating conditions, making the protection strategy more precise and effective.

[0042] Reference Figure 3 , Figure 3 This is a schematic diagram of the reference voltage generation module provided in an embodiment of this application. In some embodiments, the reference voltage generation module 215 includes a microcontroller MCU, a filter circuit 216, and an operational amplifier A1. The microcontroller MCU is electrically connected to the sampling unit 211 and is configured to dynamically generate a pulse width modulation signal based on the temperature of the switching transistor and / or the output current of the power conversion module 100. The input terminal of the filter circuit 216 is electrically connected to the microcontroller MCU and is used to filter the pulse width modulation signal. The non-inverting input terminal of the operational amplifier A1 is electrically connected to the output terminal of the filter circuit 216, and the inverting input terminal of the operational amplifier A1 is electrically connected to the output terminal of the operational amplifier A1. The output terminal of the operational amplifier A1 is used to output a threshold signal.

[0043] Pulse Width Modulation (PWM) signals are digital signals that encode analog information by adjusting the pulse duty cycle. Based on the switching transistor temperature and / or output current obtained from the sampling unit, the microcontroller runs a control algorithm to adaptively generate PWM signals with different duty cycles, achieving dynamic control.

[0044] The filter circuit 216 can use an RC (Resistor-Capacitor) low-pass filter network to filter out the high-frequency switching components in the PWM signal and extract its DC average component, thereby converting the digital PWM signal into an analog DC voltage that is proportional to the duty cycle.

[0045] like Figure 3As shown, as an example, the filter circuit 216 includes a two-stage RC filter unit. The output of the microcontroller MCU is connected to two resistors in series, which are then connected to the non-inverting input of the operational amplifier A1. The output side of each resistor is connected to the ground node through a capacitor.

[0046] An operational amplifier can be configured as a voltage follower. The non-inverting input receives the filtered voltage signal, while the inverting input is shorted to the output, creating negative feedback that ensures the output voltage accurately follows the non-inverting input voltage. Voltage followers feature high input impedance and low output impedance, effectively isolating the filter circuit from the subsequent comparator circuit, preventing the load from affecting the accuracy of the filtered output, and providing stable drive capability.

[0047] In some embodiments, the digital controller is also configured to dynamically determine thresholds based on the temperature of the switching transistor and / or the output current of the power conversion module.

[0048] In this embodiment, the digital controller 212 dynamically adjusts its internal overvoltage threshold based on the temperature of the switching transistor and / or the output current of the power conversion module 100, thus achieving adaptive control. For example, the digital controller 212 can pre-store or calculate in real time a mapping table or function reflecting the relationship between temperature, current, and the optimal protection threshold. When an increase in temperature or output current is detected, the software protection threshold is lowered accordingly; conversely, the threshold is raised.

[0049] In some embodiments, both the digital controller 212 and the reference voltage generation module 215 are dynamically adjusted based on the temperature of the switching transistor and / or the output current of the power conversion module 100, so that both the software protection channel and the hardware protection channel can adaptively adjust the protection point according to the system operating status, thereby improving the accuracy and reliability of the dual protection mechanism.

[0050] Reference Figure 4 , Figure 4 This is a schematic diagram of the comparison circuit provided in an embodiment of this application. In some embodiments, the comparison circuit 213 includes a voltage divider circuit, a comparator A2, and a first resistor R1. The first terminal of the voltage divider circuit is used to receive a threshold signal, and the second terminal of the voltage divider circuit is electrically connected to a ground node. The non-inverting input terminal of the comparator A2 is electrically connected to the voltage divider node of the voltage divider circuit, the inverting input terminal of the comparator A2 is used to receive a detection signal, and the output terminal of the comparator A2 is electrically connected to the monitoring unit 214. The first terminal of the first resistor R1 is electrically connected to the non-inverting input terminal of the comparator A2, and the second terminal of the first resistor R1 is electrically connected to the output terminal of the comparator A2.

[0051] The voltage divider circuit consists of at least two series resistors. It is used to divide the input threshold signal by a fixed ratio and provide it to the non-inverting input of the comparator, so that the reference for the comparator to compare is the voltage division value of the threshold signal.

[0052] like Figure 4 As shown, as an example, the voltage divider circuit includes a second resistor R2 and a third resistor R3. The first end of the second resistor R2 is used to receive a threshold signal, the second end of the second resistor R2 is electrically connected to the first end of the third resistor R3, and the second end of the third resistor R3 is electrically connected to a ground node.

[0053] Comparator A2 is an analog voltage comparator. It outputs a high level when the voltage at the non-inverting input is higher than the voltage at the inverting input, and a low level when the voltage at the non-inverting input is lower, thus enabling fast hardware comparison between the detection signal and the threshold. The first resistor R1 is connected between the non-inverting input and the output of comparator A2, forming a positive feedback path, giving the comparator circuit 213 hysteresis characteristics (Schmitt trigger characteristics). When the output of comparator A2 flips, the positive feedback changes the equivalent voltage threshold at the non-inverting input, preventing frequent jumps in the output of comparator A2 when the detection signal fluctuates around a single threshold. This effectively improves the anti-interference capability and output stability of the hardware protection channel.

[0054] In some embodiments, the comparator circuit 213 further includes a unidirectional conducting device, the input terminal of which is electrically connected to the second terminal of the first resistor R1, and the output terminal of which is electrically connected to the output terminal of the comparator A2.

[0055] A unidirectional conducting device is connected in series in the positive feedback path of the first resistor R1 to control the conduction direction of the positive feedback. When the output of comparator A2 is high, the unidirectional conducting device is in the conducting state, and the positive feedback is effective; when the output of comparator A2 is low, the unidirectional conducting device is cut off, and the positive feedback is blocked or weakened. By controlling the directionality of the positive feedback path, the asymmetry of the hysteresis characteristic can be further optimized, so that comparator A2 has different threshold offsets when flipping positively and negatively, thereby enhancing the noise immunity and deterministic response of comparator A2 under specific operating conditions and preventing output oscillation or malfunction under abnormal conditions.

[0056] like Figure 4 As shown, as an example, the unidirectional conducting device can be a diode D1, with the anode of diode D1 electrically connected to the second terminal of the first resistor R1, and the cathode of diode D1 electrically connected to the output terminal of comparator A2.

[0057] In some embodiments, the comparator circuit 213 further includes a Zener diode D2, the first end of which is electrically connected to the first end of the third resistor R3, and the second end of which is electrically connected to the second end of the third resistor R3.

[0058] Zener diode D2 is connected in parallel with the third resistor. When the threshold signal is within the normal range, the voltage across Zener diode D2 does not reach the breakdown voltage, and the Zener diode is in the off state, not affecting the normal operation of the voltage divider circuit. When the threshold signal rises abnormally, causing the voltage at the voltage divider node to exceed the Zener diode's regulation value, the Zener diode enters the reverse breakdown region, clamping the voltage at the voltage divider node near the regulation value, thereby limiting the maximum voltage at the non-inverting input of the comparator. Zener diode D2 provides amplitude limiting protection for the reference voltage of comparator circuit 213, ensuring that even if the threshold signal output by reference voltage generation module 215 is abnormally high, the voltage at the non-inverting input of comparator A2 will not exceed the safe range, guaranteeing the normal output and safe operation of the hardware protection circuit.

[0059] In some embodiments, the drive switching circuit 220 includes a drive chip 221, a first drive resistor branch, and at least one second drive resistor branch. The drive chip 221 is used to output a drive signal. The first end of the first drive resistor branch is electrically connected to the drive chip 221, and the second end of the first drive resistor branch is electrically connected to the drive terminal of the switching transistor. The first end of the second drive resistor branch is electrically connected to the monitoring unit 210 for receiving a monitoring signal, and the second end of the second drive resistor branch is electrically connected to the second end of the first drive resistor branch. The higher the voltage level of the voltage state, the higher the potential of the monitoring signal.

[0060] The first drive resistor branch is the main drive resistor path, connected between the drive chip 221 and the drive terminal of the switching transistor to realize the transmission of the drive signal. The second drive resistor branch is an additional resistor path connected in parallel with the first drive resistor branch, used to adjust the drive resistance of the switching transistor. When the monitoring signal is high (corresponding to the bus being at a higher voltage level), the second drive resistor branch is activated or turned on, connecting in parallel with the first drive resistor branch. This reduces the total drive resistance, and the drive current formed at the drive terminal of the switching transistor by the drive signal output by the drive chip increases accordingly. Conversely, when the monitoring signal is low (corresponding to the bus being at a lower voltage level), the second drive resistor branch is not activated, and the total drive resistance remains unchanged.

[0061] In some embodiments, the number of second drive resistor branches can be multiple, thereby the monitoring unit 210 can activate a corresponding number of second drive resistor branches according to different voltage levels of the bus, realizing different drive resistor configurations and balancing efficiency and safety requirements.

[0062] Reference Figure 5 , Figure 5This is a schematic diagram of the drive switching circuit provided in an embodiment of this application. As an example, the switching transistor is represented as Q1. The first drive resistor branch includes a diode D3 and a fourth resistor R4 connected in series, and the second drive resistor branch includes a diode D4 and a fifth resistor R5 connected in series. When the monitoring signal Vdrv is low, the fourth resistor R4 and the fifth resistor R5 are connected in parallel, and the drive resistance of the switching transistor decreases.

[0063] In this example, the drive switching circuit 220 also includes a diode D5 and a sixth resistor R6 connected in series to implement the turn-off circuit. The drive chip 221 can apply a negative voltage signal to the gate of the switching transistor through the diode D5 and the sixth resistor R6 to ensure the effective turn-off of the switching transistor.

[0064] In some other embodiments, the drive switching circuit 220 may include a drive chip 221 and an adjustable potentiometer. The drive chip 221 is used to output a drive signal. The first end of the adjustable potentiometer is electrically connected to the drive chip, the second end of the adjustable potentiometer is electrically connected to the drive end of the switching transistor, and the adjustment end of the adjustable potentiometer is electrically connected to the monitoring unit for receiving a monitoring signal. The higher the voltage level of the voltage state, the smaller the resistance value of the adjustable potentiometer.

[0065] In this embodiment, the adjustable potentiometer is an electronic device whose resistance value can be continuously or steppedly adjusted by an external control signal, such as a digital potentiometer. When the bus voltage is at a lower voltage level, the monitoring signal keeps the adjustable potentiometer at a higher resistance value, resulting in a smaller drive current. When the bus voltage rises to a higher voltage level, the potential of the monitoring signal changes accordingly, causing the resistance value of the adjustable potentiometer to decrease, thereby directly reducing the total resistance of the drive circuit and increasing the drive current. Thus, the drive switching circuit 220 can achieve continuous adjustment of the drive resistance, making the adjustment of the drive current smoother, with high circuit integration, facilitating digital control and automated adjustment.

[0066] One embodiment of this application also provides a photovoltaic system, which includes a photovoltaic module, a DC bus, a power conversion module 100, and a drive module 200. The photovoltaic module is used to output DC voltage; the DC bus is electrically connected to the output terminal of the photovoltaic module; the power conversion module 100 is electrically connected to the DC bus and includes at least one switching transistor; the drive module 200 is electrically connected to the drive terminal of the switching transistor and is used to drive the switching transistor to turn on or off.

[0067] A photovoltaic module is an array composed of multiple photovoltaic cells connected in series and / or parallel, used to convert solar energy into direct current (DC) electricity and output DC voltage. A DC bus is electrically connected to the output terminal of the photovoltaic module, used to collect and transmit the DC electricity output by the photovoltaic module, and simultaneously provide a stable DC input to the power conversion module 100. The specific structure and principle of the power conversion module 100 and the drive module 200 can be referred to the foregoing embodiments. The photovoltaic system can adopt the technical solutions in each embodiment, which also have the corresponding technical effects.

[0068] As an example, the power conversion module 100 and drive module 200 can be integrated into a photovoltaic inverter, which is electrically connected to the photovoltaic modules. In actual operation, the output voltage of a photovoltaic system fluctuates within a wide range due to environmental factors such as light intensity and temperature. In this example, the photovoltaic inverter can automatically increase the drive current to reduce switching losses under high-voltage stress when the DC bus voltage rises due to strong sunlight and low temperature; conversely, it can automatically decrease the drive current to avoid unnecessary drive losses when the DC bus voltage drops due to weak sunlight and high temperature. Therefore, the photovoltaic system can balance efficiency and safety performance under different environmental conditions, improving the system's power generation efficiency, reliability, and service life across the entire operating range.

[0069] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A drive module for a power conversion module, characterized in that, The power conversion module includes a switching transistor, and the input side of the power conversion module is electrically connected to the bus. The drive module includes: A monitoring unit is electrically connected to the bus and configured to detect the voltage status of the bus and generate a monitoring signal, wherein the voltage status includes multiple voltage level states; A drive switching circuit is electrically connected to the monitoring unit and the switching transistor, and is configured to switch the drive state in response to the monitoring signal to generate a drive signal and transmit the drive signal to the drive terminal of the switching transistor. The driving signal is used to drive the switch to turn on or off. The higher the voltage level of the voltage state, the greater the driving current generated by the driving signal at the driving terminal of the switch.

2. The driving module according to claim 1, characterized in that, The monitoring signal includes a protection signal, which represents the highest voltage level among the various voltage level states. The monitoring unit includes: A sampling unit is electrically connected to the bus and configured to detect the voltage of the bus and generate a detection signal; A digital controller, electrically connected to the sampling unit, is configured to generate a first overvoltage signal when the detected value of the detection signal is greater than or equal to a threshold. A comparison circuit is electrically connected to the sampling unit and configured to compare the detection signal with a threshold signal, and generate a second overvoltage signal when the signal value of the detection signal is greater than or equal to the signal value of the threshold signal. The monitoring unit is electrically connected to the digital controller, the comparison circuit, and the drive switching circuit, respectively, and is configured to generate the protection signal when receiving the first overvoltage signal and / or the second overvoltage signal.

3. The driving module according to claim 2, characterized in that, The sampling unit is also configured to acquire the temperature of the switching transistor and / or the output current of the power conversion module; The driver module also includes: The reference voltage generation module is electrically connected to the sampling unit and the comparison circuit, and is configured to dynamically generate a threshold signal with a corresponding signal value based on the temperature of the switching transistor and / or the output current of the power conversion module.

4. The driving module according to claim 3, characterized in that, The reference voltage generation module includes: A microcontroller, electrically connected to the sampling unit, is configured to dynamically generate a pulse width modulation signal based on the temperature of the switching transistor and / or the output current of the power conversion module. A filtering circuit, the input of which is electrically connected to the microcontroller, is used to filter the pulse width modulation signal; An operational amplifier is provided, wherein the non-inverting input terminal of the operational amplifier is electrically connected to the output terminal of the filter circuit, the inverting input terminal of the operational amplifier is electrically connected to the output terminal of the operational amplifier, and the output terminal of the operational amplifier is used to output the threshold signal.

5. The driving module according to claim 3, characterized in that, The digital controller is also configured to dynamically determine the threshold based on the temperature of the switching transistor and / or the output current of the power conversion module.

6. The driving module according to claim 2, characterized in that, The comparison circuit includes: A voltage divider circuit, wherein the first terminal of the voltage divider circuit is used to receive the threshold signal, and the second terminal of the voltage divider circuit is electrically connected to a ground node; The comparator has its non-inverting input terminal electrically connected to the voltage divider node of the voltage divider circuit, its inverting input terminal used to receive the detection signal, and its output terminal electrically connected to the monitoring unit. A first resistor, the first end of which is electrically connected to the non-inverting input terminal of the comparator, and the second end of which is electrically connected to the output terminal of the comparator.

7. The driving module according to claim 6, characterized in that, The comparison circuit further includes: A unidirectional conducting device, wherein the input terminal of the unidirectional conducting device is electrically connected to the second terminal of the first resistor, and the output terminal of the unidirectional conducting device is electrically connected to the output terminal of the comparator.

8. The driving module according to claim 6, characterized in that, The voltage divider circuit includes a second resistor and a third resistor. The first end of the second resistor is used to connect to the threshold signal. The second end of the second resistor is electrically connected to the first end of the third resistor. The second end of the third resistor is electrically connected to the grounding node. The comparison circuit further includes: A Zener diode, wherein the first end of the Zener diode is electrically connected to the first end of the third resistor, and the second end of the Zener diode is electrically connected to the second end of the third resistor.

9. The drive module according to any one of claims 1-8, characterized in that, The drive switching circuit includes: A driver chip is used to output the drive signal; A first driving resistor branch, wherein the first end of the first driving resistor branch is electrically connected to the driving chip, and the second end of the first driving resistor branch is electrically connected to the driving end of the switching transistor. At least one second driving resistor branch, the first end of the second driving resistor branch is electrically connected to the monitoring unit for receiving the monitoring signal, and the second end of the second driving resistor branch is electrically connected to the second end of the first driving resistor branch; The higher the voltage level of the voltage state, the higher the potential of the monitoring signal.

10. The driving module according to any one of claims 1-8, characterized in that, The drive switching circuit includes: A driver chip is used to output the drive signal; An adjustable potentiometer, wherein the first terminal of the adjustable potentiometer is electrically connected to the driving chip, the second terminal of the adjustable potentiometer is electrically connected to the driving terminal of the switching transistor, and the adjustment terminal of the adjustable potentiometer is electrically connected to the monitoring unit for receiving the monitoring signal; The higher the voltage level of the voltage state, the lower the resistance value of the adjustable potentiometer.

11. A photovoltaic system, characterized in that, include: Photovoltaic modules are used to output DC voltage; A DC bus is electrically connected to the output terminal of the photovoltaic module. A power conversion module is electrically connected to the DC bus, and the power conversion module includes at least one switching transistor. The driving module according to any one of claims 1-10 is electrically connected to the driving terminal of the switching transistor and is used to drive the switching transistor to turn on or off.

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