Control circuit and control method of power module, power module and charging pile

Abstract

The application provides a control circuit, a control method, a power module and a charging pile of a power module. The power module comprises a voltage conversion circuit, and the control circuit comprises a sampling comparison circuit, a latch circuit and a processing circuit. The sampling comparison circuit is used for sampling an output parameter of the voltage conversion circuit, outputting a first comparison signal when the output parameter is less than or equal to a first threshold value, and outputting a second comparison signal when the output parameter is greater than or equal to a second threshold value, the second threshold value being greater than the first threshold value. The latch circuit is used for outputting a first latch signal of a first time length to the processing circuit when the first comparison signal is received, and outputting a second latch signal of a second time length when the second comparison signal is received. The processing circuit is used for enabling a pulse signal and stopping a pulse signal when the first latch signal and the second latch signal are received. The application can reduce the output ripple of the power module under no-load and light-load conditions, and improve the product competitiveness.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a control circuit and control method for a power module, a power module, and a charging pile. Background Technology

[0002] Switching power supplies have advantages such as low power consumption, high efficiency, and wide voltage regulation range, and are therefore widely used in the field of electronic power. However, in some scenarios, such as under no-load or light-load conditions, switching power supplies, including those with pulse width modulation (PWM) and frequency modulation (FM) types, may experience severe voltage or current regulation problems.

[0003] The traditional solution is to use a burst mode control method. Burst mode can control alternating enable and disable pulses, which can reduce the overall gain of the topology to achieve voltage or current regulation. However, the output ripple in burst mode is very large. Therefore, how to reduce the output ripple of switching power supplies under light load or no-load conditions is a pressing problem to be solved. Summary of the Invention

[0004] In view of this, this application provides a control circuit and control method for a power module, a power module and a charging pile, which can reduce the output ripple of the power module under light load or no load and increase the adaptability of the product.

[0005] Embodiments of this application provide a control circuit for a power module. The power module includes a voltage conversion circuit for supplying power to a load. The control circuit includes a sampling and comparison circuit, a latching circuit, and a processing circuit. The sampling and comparison circuit samples the output parameters of the voltage conversion circuit, outputs a first comparison signal when the output parameters are less than or equal to a first threshold, and outputs a second comparison signal when the output parameters are greater than or equal to a second threshold. The second threshold may be greater than the first threshold. The latching circuit outputs a first latch signal of a first duration upon receiving the first comparison signal, and outputs a second latch signal of a second duration upon receiving the second comparison signal. The processing circuit outputs a pulse signal to the voltage conversion circuit upon receiving the first latch signal, and stops outputting the pulse signal to the voltage conversion circuit upon receiving the second latch signal.

[0006] By employing embodiments of this application, the sampled output parameters are limited, enabling the power module to enter intermittent mode under no-load and light-load conditions, and reducing the output ripple of the power module under light-load or no-load conditions.

[0007] As an optional implementation, the first duration and the second duration constitute an intermittent work cycle.

[0008] As an optional implementation, the sampling and comparison circuit may include a first comparator. The first input terminal of the first comparator samples the output parameters, the second input terminal of the first comparator is connected to the processing circuit, and the output terminal of the first comparator outputs a first comparison signal to the latching circuit. This application uses the first comparator to sample the lower limit value of the output parameters of the voltage conversion circuit, which can limit the output parameters and thus reduce the output ripple of the power supply module under light load or no load.

[0009] As an optional implementation, the sampling and comparison circuit may further include a second comparator. The first input of the second comparator samples the output parameters, the second input of the second comparator is connected to the processing circuit, and the output of the second comparator outputs a second comparison signal to the latching circuit. This application uses a second comparator to sample the upper limit value of the output parameters of the voltage conversion circuit, which can limit the output parameters and thus reduce the output ripple of the power supply module under light load or no load.

[0010] As an optional implementation, the output parameters may include the output voltage and output current of the voltage conversion circuit.

[0011] As an optional implementation, the sampling comparator circuit can also sample the output voltage of the voltage conversion circuit. Furthermore, the sampling comparator circuit can output a first comparison signal to the latch circuit when the output voltage is less than or equal to a first voltage threshold, and output a second comparison signal to the latch circuit when the output voltage is greater than or equal to a second voltage threshold. This application reduces output voltage ripple by limiting the sampled output voltage.

[0012] As an optional implementation, the sampling comparator circuit can also sample the output current of the voltage conversion circuit. The sampling comparator circuit is also used to output a first comparison signal to the latch circuit when the output current is less than or equal to a first current threshold, and can output a second comparison signal to the latch circuit when the output voltage is greater than or equal to a second current threshold. This application reduces output current ripple by limiting the sampled output current.

[0013] Secondly, embodiments of this application also provide a control method for a power module, the power module including a voltage conversion circuit for supplying power to a load, the control method including: sampling output parameters of the voltage conversion circuit, comparing the output parameters with a first threshold and a second threshold; generating a first latch signal with a first duration when the output parameters are less than or equal to the first threshold, and generating a second latch signal with a second duration when the output parameters are greater than or equal to the second threshold; wherein the second threshold is greater than the first threshold; outputting a pulse signal to the voltage conversion circuit in response to the first latch signal, and stopping the output of the pulse signal to the voltage conversion circuit in response to the second latch signal. Embodiments of this application can limit the sampled output parameters, allowing the power module to enter an intermittent mode under no-load and light-load conditions, and reducing the output ripple of the power module under light-load or no-load conditions.

[0014] As an optional implementation, the first duration and the second duration constitute an intermittent work cycle.

[0015] Thirdly, embodiments of this application also provide a power module, the power module including a voltage conversion circuit and the control circuit described above, the control circuit being used to control the state of the power switch in the voltage conversion circuit.

[0016] Fourthly, embodiments of this application also provide a charging pile, including multiple power modules and one or more charging guns, wherein the multiple power modules are connected to the one or more charging guns to supply power to the one or more charging guns.

[0017] The control circuit and control method of the power module, the power module and the charging pile in the embodiments of this application can reduce the output ripple of the power module under light load or no load and increase the adaptability of the product. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the application environment of a power module provided in an embodiment of this application.

[0019] Figure 2 This is a schematic diagram of another application environment for a power module provided in an embodiment of this application.

[0020] Figure 3 This is a schematic diagram of another application environment for a power module provided in an embodiment of this application.

[0021] Figure 4 This is a schematic diagram of a power module provided in an embodiment of this application.

[0022] Figure 5This is another structural schematic diagram of a power module provided in an embodiment of this application.

[0023] Figure 6 Waveforms of the output current, upper limit comparison signal, lower limit comparison signal, latch signal, original signal, and pulse signal provided in the embodiments of this application.

[0024] Figure 7 This is a schematic diagram of a latching circuit provided in an embodiment of this application.

[0025] Figure 8 This is a schematic diagram of a ripple regulation circuit provided in an embodiment of this application.

[0026] Figure 9a This is a schematic diagram of a traditional voltage conversion circuit.

[0027] Figure 9b This is a schematic diagram of the driving of the voltage conversion circuit according to an embodiment of this application.

[0028] Figure 10 This is another structural schematic diagram of a power module provided in an embodiment of this application.

[0029] Figure 11 Waveforms of the output voltage, upper limit comparison signal, lower limit comparison signal, latch signal, and pulse signal provided in the embodiments of this application.

[0030] Figure 12 Another waveform diagram of the output current, upper limit comparison signal, lower limit comparison signal, latch signal and pulse signal provided in the embodiments of this application.

[0031] Figure 13 This is a flowchart illustrating a power module control method provided in an embodiment of this application.

[0032] Figure 14 This is an application scenario diagram of a charging pile provided in an embodiment of this application.

[0033] Figure 15 This is a schematic diagram of a charging pile provided in an embodiment of this application.

[0034] Figure 16 This is another structural schematic diagram of a charging pile provided in an embodiment of this application.

[0035] Figure 17 This is another structural schematic diagram of a charging pile provided in an embodiment of this application. Detailed Implementation

[0036] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or may also have a component that is centrally located. When a component is considered to be "set" on another component, it can be directly set on the other component or may also have a component that is centrally located.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0038] Currently, switching power supplies may experience severe voltage or current regulation problems under no-load or light-load conditions. A common solution is to use a burst mode control method, which alternates between enable and disable pulses to reduce the overall gain of the topology and achieve voltage or current regulation. However, the output ripple in burst mode is very large. Therefore, reducing the output ripple of switching power supplies under light-load or no-load conditions is a pressing issue that needs to be addressed.

[0039] To address the aforementioned technical problems, embodiments of this application provide a control circuit for a power module, a power module, and a charging pile. By employing embodiments of this application, the output ripple of the power module under light load or no-load conditions can be reduced, improving the safety and stability of the power module, thereby enhancing product competitiveness. Specific embodiments will be described in detail below.

[0040] Please see Figure 1 , Figure 1 The diagram shown is an environmental schematic of a power module applied to a site communication system according to an embodiment of this application.

[0041] like Figure 1 As shown, the site communication system may include a monitoring device 310, an air conditioning device 320, a power generation device 330, an AC power distribution cabinet 340, a power cabinet 350, a DC power distribution cabinet 360, a backup power supply 370, and a communication device 380.

[0042] The monitoring device 310 can establish communication connections with the air conditioning unit 320, the power generation unit 330, the AC distribution cabinet 340, the power cabinet 350, the DC distribution cabinet 360, and the backup power supply 370 via a communication bus to monitor their operating status. The air conditioning unit 320, the power generation unit 330, the AC distribution cabinet 340, and the power cabinet 350 can be connected via an AC (Alternating Current) bus. The power cabinet 350, the DC distribution cabinet 360, the backup power supply 370, and the communication equipment 380 can be connected via a DC (Direct Current) bus.

[0043] The air conditioning unit 320 can be used to dissipate heat from the equipment in the site communication system 300. The power generation unit 330 can be used to provide AC input to the power module.

[0044] The AC power distribution cabinet 340 can be used for AC power distribution. The power cabinet 350 may include multiple power modules connected in parallel.

[0045] The DC power distribution cabinet 360 can distribute power to the output of the power cabinet 350, for example, the output of the power cabinet 350 can supply power to the communication equipment 380. The backup power supply 370 can be a battery or an uninterrupted power supply (UPS), and the backup power supply 370 can be used to provide emergency power when the power cabinet 350 loses power or malfunctions.

[0046] Please see Figure 2 , Figure 2 The diagram shown is an application environment schematic of a power module 100 provided in an embodiment of this application.

[0047] exist Figure 2 In the scenario shown, the power module 100 can be used to charge the electric vehicle 200 using an external power source. It is understood that in other embodiments of this application, the power module 100 is not limited to use in the electric vehicle 200.

[0048] For example, the power module 100 can be an on-board charger in the electric vehicle 200. The AC power grid 210 can output AC power to the AC charging pile 220, and the AC charging pile 220 can output AC power to the power module 100. The power module 100 can process or convert the received AC power and charge the battery 230 in the electric vehicle 200.

[0049] Please see Figure 3 , Figure 3The diagram shown is a schematic diagram of another application environment of the power module 100 according to an embodiment of this application.

[0050] exist Figure 3 In the scenario shown, the power module 100 can be applied to the DC charging pile 250. The AC power grid 210 can output AC power to the transformer 240, which converts the AC power and outputs it to the DC charging pile 250. The DC charging pile 250 processes or converts the AC power to charge the battery 230 in the electric vehicle 200.

[0051] In some possible application scenarios, the power module 100 can be used in AC charging piles, DC charging piles, on-board chargers, high-power charging piles, ultra-high-power charging piles, and portable charging piles, etc. It is understood that the embodiments of this application do not limit the types and applications of power supply products; this application can be applied to all types of switching power supply products.

[0052] The internal structure of the power module will be described in detail below.

[0053] Please see Figure 4 , Figure 4 The diagram shown is a structural schematic of a power module 100 provided in one embodiment of this application.

[0054] In this embodiment, the power module 100 may include a voltage conversion circuit 10 and a control circuit 20.

[0055] The voltage conversion circuit 10 can be electrically connected between the input power supply 30 and the load 40. The voltage conversion circuit 10 can convert the voltage of the input power supply 30 and output a voltage to the load 40 to power the load 40. It can be understood that in this embodiment, the load 40 is a light load or no load type.

[0056] The control circuit 20 can be electrically connected to the voltage conversion circuit 10 and can acquire the output voltage or output current of the voltage conversion circuit 10.

[0057] The control circuit 20 can also process the output voltage of the voltage conversion circuit 10 and output a pulse width modulation (PWM) signal to the voltage conversion circuit 10 accordingly.

[0058] Optionally, the input power source 30 can be a mains power source. The mains power source can be a residential mains power supply network. This mains power source can be a 120V or 220V mains power source.

[0059] For example, the input power supply 30 can output a first voltage to the voltage conversion circuit 10, which converts the first voltage into a second voltage. It is understood that in some embodiments, the first voltage can be a 220V AC voltage, and the second voltage can be a 48V DC voltage.

[0060] The voltage conversion circuit 10 can output the converted second voltage to the load 40 to supply power to the load 40.

[0061] Please see Figure 5 , Figure 5 The diagram shown is a structural schematic of a power module 100 provided in another embodiment of this application.

[0062] In this embodiment, the voltage conversion circuit 10 is a switching topology based on a resonant LLC. In other words, this embodiment can be applied to a PFM frequency modulation type resonant switching topology, such as a resonant LLC switching topology, and can be used for ripple suppression of the power module output voltage.

[0063] Specifically, the voltage conversion circuit 10 may include a power factor correction (PFC) circuit 11, an LLC resonant converter 12, and a rectifier filter circuit.

[0064] It is understood that in this embodiment, the PFC circuit 11 can be electrically connected between the input power supply 30 and the LLC resonant converter 12, and the rectifier filter circuit is electrically connected to the output terminal of the LLC resonant converter 12.

[0065] The voltage conversion circuit 10 may further include a bus capacitor C1 and a bus capacitor C2. The first terminal of the bus capacitor C1 is electrically connected to the first output terminal of the PFC circuit 11 and the first input terminal of the LLC resonant converter 12. The second terminal of the bus capacitor C1 is electrically connected to the first terminal of the bus capacitor C2, the second output terminal of the PFC circuit 11, and the second input terminal of the LLC resonant converter 12. The second terminal of the bus capacitor C2 is electrically connected to the third output terminal of the PFC circuit 11 and the third input terminal of the LLC resonant converter 12.

[0066] In this embodiment, the PFC circuit 11 can be electrically connected to the input power supply 30. The PFC circuit 30 is configured to boost the voltage output by the input power supply 30, enabling the PFC circuit 30 to provide a wide range of output voltages. The PFC circuit 11 can effectively improve the power factor, thereby achieving high conversion efficiency.

[0067] The LLC resonant converter 12 can receive the output voltage of the PFC circuit 11 and convert the output voltage of the PFC circuit 11 to output a power supply voltage to the rectifier and filter circuit. The rectifier and filter circuit can rectify and filter the power supply voltage and output it to the load 40 to power the load 40.

[0068] In this embodiment, the rectifier filter circuit may include a resistor R1, a diode D1, and a capacitor C3.

[0069] The resistor R1 can be electrically connected between the first output terminal of the LLC resonant converter 12 and the anode of the diode D1. The cathode of the diode D1 can be electrically connected between the first terminal of the capacitor C3 and the first terminal of the load 40. The second terminal of the capacitor C3 can be electrically connected between the second output terminal of the LLC resonant converter 12 and the second terminal of the load 40.

[0070] It is understood that in some optional application scenarios, the load 40 can be a battery. In other words, the supply voltage output by the LLC resonant converter 12 can charge the battery. For example, in this embodiment, the load can be the on-board power battery of an electric vehicle, and the power module can charge the power battery of the electric vehicle by outputting a constant current.

[0071] It is understood that the rectifier-filter circuit may further include a comparator U1, resistors R2, R3, and R4. Resistor R2 can be electrically connected between the first end of resistor R1 and the first input terminal of comparator U1, and resistor R3 can be electrically connected between the second end of resistor R2 and the second input terminal of comparator U1. The first end of resistor R3 can be electrically connected to the second input terminal of comparator U1, and the second end of resistor R3 can be electrically connected to the output terminal of comparator U1.

[0072] In this embodiment, the control circuit 20 can be electrically connected to the output terminal of the comparator U1. The control circuit 20 can sample the output voltage or output current of the voltage conversion circuit 10.

[0073] Specifically, the control circuit 20 may include a sampling comparison circuit 21, a latch circuit 22, and a processing circuit 23.

[0074] The sampling comparison circuit 21 can be electrically connected to the voltage conversion circuit 10, the latch circuit 22, and the processing circuit 23. The processing circuit 23 can be electrically connected to the latch circuit 22 and the LLC resonant converter 12.

[0075] In one scenario, the sampling comparison circuit 21 can sample the output current I of the voltage conversion circuit 10. out And based on the sampled output current I out The corresponding pulse signal is output to the voltage conversion circuit 10.

[0076] For example, the sampling comparison circuit 21 can sample the output current I of the voltage conversion circuit 10. out And based on the sampled output current I out The output comparison signal is given to the latch circuit 22.

[0077] The sampling comparison circuit 21 may include comparator U2 and comparator U3.

[0078] The first input terminal of comparator U2 can be electrically connected to the output terminal of comparator U1, and the second input terminal of comparator U2 can be electrically connected to the processing circuit 23. The output terminal of comparator U2 can be electrically connected to the latch circuit 22. The first input terminal of comparator U2 can be a positive input terminal, and the second input terminal of comparator U2 can be a negative input terminal. It can be understood that comparator U2 can serve as the ripple upper limit comparator in the embodiments of this application.

[0079] The first input terminal of comparator U3 can be electrically connected to the output terminal of comparator U1, and the second input terminal of comparator U3 can be electrically connected to the processing circuit 23. The output terminal of comparator U3 can be electrically connected to the latch circuit 22. The first input terminal of comparator U3 can be a negative input terminal, and the second input terminal of comparator U2 can be a positive input terminal. It can be understood that comparator U3 can serve as the ripple lower limit comparator in the embodiments of this application.

[0080] It is understood that the processing circuit 23 in this embodiment may include a ripple adjustment circuit 231, a loop module 232, a comparator U4, an analog-to-digital converter 233, and a pulse signal generation circuit 234.

[0081] The first input terminal of the comparator U4 can receive a reference current I. ref The second input terminal of the comparator U4 is electrically connected to the analog-to-digital converter 233. The output terminal of the comparator U4 is electrically connected to the loop module 232. The loop module 232 can be electrically connected to the ripple adjustment circuit 231. The pulse signal generation circuit 234 can be electrically connected to the ripple adjustment circuit 231.

[0082] In this embodiment, the analog-to-digital converter 233 can obtain the output current I of the voltage conversion circuit 10. out The comparator U4 can convert the reference current I...ref With the output current I out The comparison is performed, and an error signal is output. This error signal can be an analog signal, and the loop module 232 can output the original PWM signal PWM_Raw based on the error signal output by the comparator U4.

[0083] Please refer to the following: Figure 6 The first input terminal of the comparator U2 can sample the output current I of the voltage conversion circuit 10. out The second input terminal of the comparator U2 can receive the first current threshold I output by the ripple adjustment circuit 231. ref1 Wherein, the first current threshold I ref1 This can be used as the upper limit value of the current in the embodiments of this application.

[0084] The comparator U2 can convert the output current I of the voltage conversion circuit 10. out With the first current threshold I ref1 A comparison is performed, and a first comparison signal is output after the comparison. This first comparison signal can be the upper limit comparison signal S1.

[0085] In some embodiments, the first current threshold I ref1 The following formula (1) can be satisfied:

[0086] I ref1 =I ref +I delta (1)

[0087] Among them, I ref I is the average value of the output current. delta To control the output current ripple to half its magnitude, i.e., I delta This is the ripple control quantity.

[0088] The first input terminal of the comparator U3 can sample the output current I of the voltage conversion circuit 10. out The second input terminal of the comparator U3 can receive the second current threshold I output by the ripple adjustment circuit 231. ref2 Wherein, the second current threshold I ref2 The first current threshold I can be used as the lower current limit value in the embodiments of this application. ref1 Greater than the second current threshold I ref2 The comparator U3 can convert the output current I of the voltage conversion circuit 10. out With the second current threshold I ref2 A comparison is performed, and a second comparison signal is output after the comparison. This second comparison signal can be the lower limit comparison signal S2.

[0089] In some embodiments, the second current threshold I ref2 The following formula (2) can be satisfied:

[0090] I ref2 =I ref -I delta (2)

[0091] For example, such as Figure 6 As shown, assume I ref 48V, I delta If it is 0.3V, then the first current threshold I ref1 It is 48.3V, the second current threshold I ref2 It is 47.7V.

[0092] If the output current I out At a voltage of 47.69V, comparator U3 samples the output current I. out Less than the second current threshold I ref2 That is, the output current I out When the current lower limit is reached, the comparator U3 outputs a high-level lower limit comparison signal S2, and the latch circuit 22 latches the high-level lower limit comparison signal S2. In other words, after receiving the high-level lower limit comparison signal S2, the latch circuit 22 can output a high-level latch signal S' with a first duration t1 to the ripple adjustment circuit 231.

[0093] If the output current I out At a voltage of 48.31V, comparator U2 samples the output current I. out Greater than the first current threshold I ref1 That is, the output current I out When the current upper limit is reached, the comparator U2 outputs a high-level upper limit comparison signal S1, and the latch circuit 22 latches the high-level upper limit comparison signal S1. In other words, after receiving the high-level upper limit comparison signal S1, the latch circuit 22 can output a low-level latch signal S' with a second duration t2 to the ripple adjustment circuit 231. The processing circuit 231 can output a pulse signal PWM_LLC to the voltage conversion circuit 10 when it receives the high-level latch signal S'. The processing circuit 231 can also choose not to output the pulse signal PWM_LLC to the voltage conversion circuit 10 when it receives the low-level latch signal S'. It can be understood that t1 and t2 can be the burst working cycle time in burst mode.

[0094] The ripple regulation circuit 231 can generate a corresponding pulse signal PWM_LLC based on the latch signal S' and the original signal PWM_Raw. For example, the pulse signal can be used to drive the power transistor in the LLC resonant converter 12, thereby achieving current regulation control and ripple control under light load and no-load conditions for the power supply module.

[0095] Specifically, the ripple regulation circuit 231 outputs an upper limit reference current signal to the comparator U2, and also outputs a lower limit reference current signal to the comparator U3. It can be understood that the upper limit reference current signal and the lower limit reference current signal can be adjusted according to the actual input and output operating conditions of the power supply module.

[0096] In another scenario, the sampling comparison circuit 21 can sample the output voltage V of the voltage conversion circuit 10. out And based on the sampled output voltage V out The corresponding pulse signal is output to the voltage conversion circuit 10.

[0097] For example, the sampling comparison circuit 21 can sample the output voltage V of the voltage conversion circuit 10. out And based on the sampled output voltage V out The output comparison signal is given to the latch circuit 22.

[0098] The first input terminal of the comparator U4 can receive a reference voltage V. ref The analog-to-digital converter 233 can obtain the output voltage V of the voltage conversion circuit 10. out The comparator U4 can convert the reference voltage V ref With the output voltage V out The comparison is performed, and an error signal is output. This error signal can be an analog signal, and the loop module 232 can output the original PWM signal PWM_Raw based on the error signal output by the comparator U4.

[0099] The first input terminal of the comparator U2 can sample the output voltage V of the voltage conversion circuit 10. out The second input terminal of the comparator U2 can receive the first voltage threshold V output by the ripple adjustment circuit 231. ref1 Wherein, the first voltage threshold V ref1 This can be used as the upper limit value of the voltage in the embodiments of this application. The comparator U2 can convert the output voltage V of the voltage conversion circuit 10. out With the first voltage threshold V ref1A comparison is performed, and a first comparison signal is output after the comparison. This first comparison signal can be the upper limit comparison signal S1.

[0100] In some embodiments, the first voltage threshold V ref1 The following formula (3) can be satisfied:

[0101] V ref1 =V ref +V delta (3)

[0102] Among them, V ref V is the voltage reference value for the output voltage current regulator loop. delta To control the output voltage ripple to half its magnitude.

[0103] The first input terminal of the comparator U3 can sample the output voltage I of the voltage conversion circuit 10. out The second input terminal of the comparator U3 can receive the second voltage threshold V output by the ripple adjustment circuit 231. ref2 Wherein, the second voltage threshold V ref2 The first voltage threshold V can be used as the lower voltage limit value in the embodiments of this application. ref1 Greater than the second voltage threshold V ref2 The comparator U3 can convert the output voltage V of the voltage conversion circuit 10. out With the second voltage threshold V ref2 A comparison is performed, and a second comparison signal is output after the comparison. This second comparison signal can be the lower limit comparison signal S2.

[0104] In some embodiments, the second voltage threshold V ref1 The following formula (4) can be satisfied:

[0105] V ref1 =V ref -V delta (4)

[0106] The latch circuit 22 receives the upper limit comparison signal S1 and the lower limit comparison signal S2, and outputs a latch signal S' to the ripple adjustment circuit 231.

[0107] The ripple adjustment circuit 231 can generate a corresponding pulse signal PWM_LLC based on the latch signal S' and the original signal PWM_Raw.

[0108] Please see Figure 7 This is a schematic diagram of the latch circuit 22 provided in one embodiment of this application.

[0109] In this embodiment, the latch circuit 22 may include an OR logic gate 221, an AND logic gate 222, and a NOT logic gate 223.

[0110] Specifically, the first input of the NOT gate 223 is connected to the output of the comparator U3 to receive the lower limit comparison signal S2. The second input of the NOT gate 223 is connected to the output of the AND gate 222. The input of the OR gate 221 is connected to the output of the comparator U2 to receive the upper limit comparison signal S1. The first input of the AND gate 222 is connected to the output of the NOT gate 223, and the second input of the AND gate 222 is connected to the output of the OR gate 221. The output of the AND gate 222 is connected to the ripple adjustment circuit 231, and the output of the AND gate 222 outputs a latch signal S' to the ripple adjustment circuit 231.

[0111] In other alternative implementations, the latch circuit 22 can also be implemented using flip-flop gates or complex programmable logic devices (CPLDs) or field-programmable gate arrays (FPGAs). The embodiments in this application do not impose specific limitations on this.

[0112] Please see Figure 8 This is a schematic diagram of the ripple adjustment circuit 231 provided in one embodiment of this application.

[0113] In this embodiment, the ripple adjustment circuit 231 may include an AND logic gate 235.

[0114] The first input terminal of the AND gate 235 is connected to the latch circuit 22. In other words, the first input terminal of the AND gate 235 can be connected to the output terminal of the AND gate 222 to receive the latch signal S' output by the output terminal of the AND gate 222. The second input terminal of the AND gate 235 can be connected to the loop module 232 to receive the raw signal PWM_Raw output by the loop module 232. The output terminal of the AND gate 235 can output the pulse signal PWM_LLC.

[0115] Please see Figure 9a , Figure 9a This is a schematic diagram of the pulse signal and output voltage waveforms during one duty cycle in the common Burst mode.

[0116] like Figure 9aAs shown, T1 is the burst cycle time in burst mode, T2 is the time interval between the last pulse of each burst cycle and the first pulse of the next burst cycle, and T3 is the time interval between each pulse. Specifically, T1 is 120µs, T2 is 60µs, and T3 is 10µs. It can be understood that T3 corresponds to the PWM switching cycle or frequency.

[0117] Please see Figure 9b , Figure 9b This is a schematic diagram of the pulse signal and output voltage waveforms during one working cycle in the Burst mode of this embodiment.

[0118] like Figure 9b As shown, T4 is the burst cycle time in burst mode, T5 is the time interval between the last pulse of each burst cycle and the first pulse of the next burst cycle, and T6 is the time interval between each pulse. Specifically, T4 is 60µs, T5 is 30µs, and T6 is 10µs. It can be understood that T6 corresponds to the PWM switching cycle or frequency.

[0119] from Figure 9a and Figure 9b As can be seen, compared with the prior art, the embodiments of this application can increase the interval frequency of the burst cycle, thereby reducing the duration of the burst cycle, which can reduce the output ripple of the power module under light load and no-load conditions.

[0120] Based on the above Figure 5 The control circuit 20 and power module 100 shown in the embodiment sample the output current signal I. out and output current signal I out The upper limit comparator and lower limit comparator compare the signal with the upper limit threshold and lower limit threshold respectively, generating upper limit comparison signal S1 and lower limit comparison signal S2. These upper limit comparison signal S1 and lower limit comparison signal S2 are then processed by the signal latching circuit 22 to generate latch signal S', which is then combined with the original PWM signal PWM_Raw output by the loop module 232 to generate the final pulse signal PWM_LLC, thereby driving the power transistor to switch. This reduces the duration of the burst duty cycle, thereby achieving current regulation control and ripple control under light load and no-load conditions, improving the stability of the power module and the competitiveness of the power product.

[0121] Please see Figure 10 , Figure 10 The diagram shown is a structural schematic of a power module 100 provided in another embodiment of this application.

[0122] and Figure 5 The difference between the power module 100 shown in the embodiment is that, in this embodiment, as Figure 10 As shown, the voltage conversion circuit 10 can be a regulated Buck / Boost type switching topology. In other words, this embodiment can be applied to PWM pulse width modulation Boost type switching topologies, as well as other PWM type topologies, such as Buck, Buck-Boost, push-pull, half-bridge, full-bridge, etc., and can be used for ripple suppression of the power module output voltage.

[0123] In the specific implementation of this embodiment, the voltage conversion circuit 10 may include a bridge rectifier 14, an inductor L1, a capacitor C4, a power switch S1, and a rectifier filter circuit.

[0124] The bridge rectifier 14 may include diodes D2, D3, D4, and D5. The anode of diode D2 can be electrically connected to the cathode of diode D3 and the first output terminal of the input power supply 30. The cathode of diode D2 can be electrically connected to the cathode of diode D4 and the first terminal of inductor L1 and capacitor C4, with the second terminal of capacitor C4 grounded. The anode of diode D4 can be electrically connected to the cathode of diode D5 and the second output terminal of the input power supply 30. The anodes of diodes D5 and D3 are both grounded.

[0125] The first terminal of the power switch S1 can be connected to the pulse signal generating circuit 234. The second terminal of the power switch S1 can be electrically connected to the second terminal of the inductor L1 and the rectifier filter circuit. The third terminal of the power switch S1 is grounded. It can be understood that the first terminal of the power switch S1 can serve as the control terminal of the power switch S1. In some alternative solutions, the first terminal of the power switch S1 can be signal-connected to the pulse signal generating circuit 234. In other alternative solutions, the first terminal of the power switch S1 can also be electrically connected to the pulse signal generating circuit 234. Based on this design, the pulse signal generating circuit 234 can output a pulse signal to the first terminal of the power switch S1, thereby controlling the on and off states of the power switch S1.

[0126] The rectifier filter circuit may include diode D6 and capacitor C5.

[0127] The anode of diode D6 can be electrically connected to the second terminal of inductor L1 and the second terminal of power switch S1. The cathode of diode D6 can be electrically connected to the first terminal of capacitor C5 and the first terminal of load 40. The second terminal of capacitor C5 can be electrically connected to the second terminal of load 40. The second terminal of capacitor C5 can also be grounded.

[0128] In this embodiment, the cathode of the diode D6 can also be electrically connected to the sampling and comparison circuit 21. In this way, the sampling and comparison circuit 21 can sample the output voltage or output current of the voltage conversion circuit 10.

[0129] Please refer to the following: Figure 11 The first input terminal of the comparator U2 can sample the output voltage V of the voltage conversion circuit 10. out The second input terminal of the comparator U2 can receive the first voltage threshold V output by the ripple adjustment circuit 231. ref1 Wherein, the first voltage threshold V ref1 This can be the upper voltage limit value in the embodiments of this application. The comparator U2 can convert the output voltage V of the voltage conversion circuit 10. out With the first voltage threshold V ref1 The comparison is performed, and the upper limit comparison signal S1 is output after the comparison.

[0130] The first input terminal of the comparator U3 can sample the output voltage V of the voltage conversion circuit 10. out The second input terminal of the comparator U3 can receive the second voltage threshold V output by the ripple adjustment circuit 231. ref2 Wherein, the second voltage threshold V ref2 This can be the lower voltage limit value in the embodiments of this application, where the first voltage threshold V is... ref1 Greater than the second voltage threshold V ref2 The comparator U3 can convert the output voltage V of the voltage conversion circuit 10. out With the second voltage threshold V ref2 The comparison is performed, and the lower limit comparison signal S2 is output after the comparison.

[0131] Understandable. Figure 10 In the control circuit 20 shown in the embodiment, the sampling and comparison circuit 21 can also sample the output current I of the voltage conversion circuit 10. out And based on the sampled output current I out The output comparison signal is given to the latch circuit 22.

[0132] The first input terminal of the comparator U2 can sample the output current I of the voltage conversion circuit 10. out The second input terminal of the comparator U2 can receive the first current threshold I output by the ripple adjustment circuit 231. ref1 The comparator U2 can convert the output current I of the voltage conversion circuit 10. out With the first current threshold I ref1The comparison is performed, and the upper limit comparison signal S1 is output after the comparison.

[0133] The first input terminal of the comparator U3 can sample the output current I of the voltage conversion circuit 10. out The second input terminal of the comparator U3 can receive the second current threshold I output by the ripple adjustment circuit 231. ref2 The comparator U3 can convert the output current I of the voltage conversion circuit 10. out With the second current threshold I ref2 The comparison is performed, and the lower limit comparison signal S2 is output after the comparison.

[0134] The latch circuit 22 receives the upper limit comparison signal S1 and the lower limit comparison signal S2, and outputs a latch signal S' to the ripple adjustment circuit 231.

[0135] The ripple regulation circuit 231 can generate a corresponding pulse signal VG1 based on the latch signal S' and the duty cycle output by the loop module 232. The pulse signal VG1 can be used to drive the power switch S1 to turn on and off, thereby achieving current regulation control and ripple control under light load and no-load conditions for the power supply module.

[0136] Based on the above Figure 10 The control circuit 20 and power module 100 shown in the embodiment can achieve stable current control and ripple control under light load and no-load conditions, thereby improving the stability of the power module and the competitiveness of the power product.

[0137] It is understandable that, in one possible scenario, if the power module 100 adopts a PFM frequency modulation type resonant switching topology, when the power module 100 is under no-load or light-load conditions and enters Burst mode, the switching losses of the power transistors in the power module 100 can be reduced by decreasing the maximum switching frequency of the pulse signal LLC. For example... Figure 12 As shown, the switching frequency of the pulse signal PWM_LLC2 is less than that of the pulse signal PWM_LLC1, meaning that the switching frequency of the pulse signal PWM_LLC2 is reduced. The power module 100 uses the pulse signal PWM_LLC2 to drive the power switch on and off. This not only achieves stable current control and ripple control under light load and no-load conditions, but also reduces the power switch losses.

[0138] Please see Figure 13 , Figure 13This is a flowchart illustrating a control method for a power module according to an embodiment of this application. The control method can be applied to the power module 100 and includes the following steps:

[0139] Step S131: Sample the output parameters of the voltage conversion circuit.

[0140] by Figure 5 The power module 100 shown is used as an example for explanation.

[0141] The sampling comparison circuit 21 can sample the output parameters of the voltage conversion circuit 10. For example, the sampling comparison circuit 21 can sample the output current I of the voltage conversion circuit 10. out and output voltage V out .

[0142] Step S132: Compare the output parameter with the first threshold and the second threshold.

[0143] The sampling comparison circuit 21 can also compare the output parameter with a first threshold and a second threshold. Specifically, the sampling comparison circuit 21 can be used to output a first comparison signal when the output parameter is less than or equal to the first threshold, and can output a second comparison signal when the output parameter is greater than or equal to the second threshold.

[0144] Step S133: When the output parameter is less than or equal to the first threshold, a first latch signal with a first duration is generated, and when the output parameter is greater than or equal to the second threshold, a second latch signal with a second duration is generated.

[0145] The second threshold is greater than the first threshold. The output parameters may include the output voltage and output current of the voltage conversion circuit 10.

[0146] For example, the sampling and comparison circuit 21 can convert the output current I of the voltage conversion circuit 10. out With the first current threshold I ref1 A comparison is performed, and a first comparison signal is output after the comparison. This first comparison signal can be the upper limit comparison signal S1.

[0147] In some embodiments, the first current threshold I ref1 The following formula (5) can be satisfied:

[0148] I ref1 =I ref +I delta (5)

[0149] Among them, I ref I is the average value of the output current.delta To control the output current ripple to half its magnitude, i.e., I delta This is the ripple control quantity.

[0150] The sampling and comparison circuit 21 can also convert the output current I of the voltage conversion circuit 10 into a voltage conversion circuit. out With the second current threshold I ref2 A comparison is performed, and a second comparison signal is output after the comparison. This second comparison signal can be the lower limit comparison signal S2.

[0151] If the output current I out Less than or equal to the second current threshold I ref2 That is, the output current I out When the current lower limit is reached, the sampling comparison circuit 21 outputs a high-level lower limit comparison signal S2, and the latch circuit 22 latches the high-level lower limit comparison signal S2. In other words, after receiving the high-level lower limit comparison signal S2, the latch circuit 22 can output a high-level latch signal S' with a first duration t1 to the ripple adjustment circuit 231.

[0152] If the sampling and comparison circuit 21 samples the output current I out Greater than or equal to the first current threshold I ref1 That is, the output current I out When the current upper limit is reached, the comparator U2 outputs a high-level upper limit comparison signal S1, and the latch circuit 22 latches the high-level upper limit comparison signal S1. In other words, after receiving the high-level upper limit comparison signal S1, the latch circuit 22 can output a low-level latch signal S' with a second duration t2 to the ripple adjustment circuit 231.

[0153] Step S134: In response to the first latch signal, output a pulse signal to the voltage conversion circuit; in response to the second latch signal, stop outputting the pulse signal to the voltage conversion circuit.

[0154] like Figure 5 As shown, the processing circuit 231 can output a pulse signal PWM_LLC to the voltage conversion circuit 10 when it receives a high-level latch signal S'. The processing circuit 231 can also choose not to output the pulse signal PWM_LLC to the voltage conversion circuit 10 when it receives a low-level latch signal S'. It can be understood that t1 and t2 can be the burst working cycle time in burst mode.

[0155] like Figure 14As shown, embodiments of this application also provide a charging pile 400. The charging pile 400 can be electrically connected between a mains power supply 500 and a load 600. The charging pile 400 may include one or more power modules described in the above embodiments. The charging pile 400 can receive AC power output from the mains power supply 500, convert the AC power, and then supply power to the load 600. The mains power supply 500 can output three-phase AC power or single-phase AC power. In some scenarios, the load 600 can be an electric vehicle, thus the charging pile 400 can charge the electric vehicle.

[0156] Please see Figure 15 This is a schematic diagram of a charging pile provided in one embodiment of this application. In this embodiment, the charging pile 400 may include a charging gun 410 and multiple power modules described in the above embodiments. Figure 13 This explanation uses only three power modules 100a, 100b, and 100c as an example (there may be more than three modules). The power modules 100a, 100b, and 100c are connected in parallel. It can be understood that the input terminals of the power modules 100a, 100b, and 100c are connected in parallel, and the output terminals of the power modules 100a, 100b, and 100c are connected in parallel. The output terminals of the power modules 100a, 100b, and 100c are connected to the charging gun 410. The power modules 100a, 100b, and 100c can supply power to the load 600 through the charging gun 410; for example, the power modules 100a, 100b, and 100c can supply power to an electric vehicle through the charging gun 410. It is understood that in this embodiment, the charging pile 400 may also include a charging pile body (not shown in the figure), and the power modules 100a, 100b, and 100c may be disposed in the charging pile body. The charging pile body may be connected to the charging gun 410 via a charging cable.

[0157] Please see Figure 16 This is a schematic diagram of the structure of a charging pile provided in another embodiment of this application.

[0158] and Figure 15 The difference between the charging piles shown in the embodiments is that, as Figure 16 As shown, in this embodiment, the charging pile 400 may include multiple power modules 100a, 100b, 100c and multiple charging guns 410a, 410b, 410c. It can be understood that... Figure 16 The following description uses only three power modules 100a, 100b, and 100c and three charging guns 410a, 410b, and 410c as examples. The number of power modules and the number of charging guns can be more than three or less.

[0159] In this embodiment, the input terminals of power modules 100a, 100b, and 100c are connected in parallel. The output terminal of power module 100a can be connected to the charging gun 410a, the output terminal of power module 100b can be connected to the charging gun 410b, and the output terminal of power module 100c can be connected to the charging gun 410c. The following example illustrates a scenario where a charging station charges an electric vehicle: power module 100a can charge an electric vehicle via charging gun 410a, power module 100b can charge an electric vehicle via charging gun 410b, and power module 100c can charge an electric vehicle via charging gun 410c.

[0160] Please see Figure 17 This is a schematic diagram of the structure of a charging pile provided in another embodiment of this application.

[0161] and Figure 16 The difference between the charging piles shown in the embodiments is that, as Figure 17 As shown, in this embodiment, the charging pile 400 may include a switch matrix 420. The switch matrix 420 may be connected between the power modules 100a, 100b, 100c and the charging guns 410a, 410b, 410c. The charging controller within the charging pile 400 may control multiple switches in the switch matrix 420 to achieve the connection between the power modules 100a, 100b, 100c and the charging guns 410a, 410b, 410c.

[0162] For example, in one application scenario, the charging controller controls the switch matrix 410 to connect the power modules 100a and 100b to the charging gun 410. In another application scenario, the charging controller controls the switch matrix 410 to connect the power modules 100a, 100b, and 100c to the charging gun 410. In yet another application scenario, the charging controller controls the switch matrix 410 to connect the power modules 100b and 100c to the charging gun 410. In yet another application scenario, the charging controller controls the switch matrix 410 to connect the power modules 100a and 100c to the charging gun 410. In one scenario, the charging controller controls the switch matrix 410 to connect the power modules 100a, 100b, and 100c to the charging guns 410a, 410b, and 410c, respectively.

[0163] It is understood that the charging pile 400 can be configured to have different connection relationships between the multiple power modules 100a, 100b, 100c and the multiple charging guns 410a, 410b, 410c, according to actual needs. This allows it to adapt to different charging scenarios.

[0164] The above description is merely a preferred embodiment of this application and is not intended to limit this application in any way. Although the preferred embodiment has been disclosed above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A control circuit for a power supply module, the power supply module including a voltage conversion circuit for supplying power to a load, characterized in that, The control circuit includes a sampling comparison circuit, a latching circuit, and a processing circuit; The sampling and comparison circuit is used to: sample the output parameters of the voltage conversion circuit, output a first comparison signal when the output parameters are less than or equal to a first threshold, and output a second comparison signal when the output parameters are greater than or equal to a second threshold; wherein the second threshold is greater than the first threshold; The latch circuit is used to output a first latch signal with a first duration when the first comparison signal is received, and to output a second latch signal with a second duration when the second comparison signal is received; The processing circuit is configured to output a pulse signal to the voltage conversion circuit when it receives the first latch signal, and to stop outputting the pulse signal to the voltage conversion circuit when it receives the second latch signal.

2. The control circuit according to claim 1, characterized in that, The first duration and the second duration constitute one intermittent work cycle.

3. The control circuit according to claim 1 or 2, characterized in that, The sampling comparison circuit includes a first comparator, the first input terminal of the first comparator samples the output parameter, the second input terminal of the first comparator is connected to the processing circuit, and the output terminal of the first comparator outputs the first comparison signal to the latch circuit.

4. The control circuit according to claim 3, characterized in that, The sampling comparison circuit includes a second comparator. The first input terminal of the second comparator samples the output parameter, the second input terminal of the second comparator is connected to the processing circuit, and the output terminal of the second comparator outputs the second comparison signal to the latch circuit.

5. The control circuit according to claim 1, characterized in that, The output parameters include the output voltage and output current of the voltage conversion circuit.

6. The control circuit according to any one of claims 1, 2, 4 and 5, characterized in that, The sampling comparison circuit is used to sample the output voltage of the voltage conversion circuit. The sampling comparison circuit is also used to output the first comparison signal to the latch circuit when the output voltage is less than or equal to a first voltage threshold, and to output the second comparison signal to the latch circuit when the output voltage is greater than or equal to a second voltage threshold; the first voltage threshold is greater than the second voltage threshold.

7. The control circuit according to any one of claims 1, 2, 4 and 5, characterized in that, The sampling comparison circuit is used to sample the output current of the voltage conversion circuit. The sampling comparison circuit is also used to output the first comparison signal to the latch circuit when the output current is less than or equal to a first current threshold, and to output the second comparison signal to the latch circuit when the output voltage is greater than or equal to a second current threshold; the first current threshold is greater than the second current threshold.

8. A control method for a power supply module, the power supply module including a voltage conversion circuit for supplying power to a load, characterized in that, The control method includes: Sample the output parameters of the voltage conversion circuit. The output parameter is compared with a first threshold and a second threshold; A first latch signal with a first duration is generated when the output parameter is less than or equal to the first threshold, and a second latch signal with a second duration is generated when the output parameter is greater than or equal to the second threshold; wherein the second threshold is greater than the first threshold; In response to the first latch signal, a pulse signal is output to the voltage conversion circuit; in response to the second latch signal, the output of the pulse signal to the voltage conversion circuit is stopped.

9. The control method according to claim 8, characterized in that, The first duration and the second duration constitute one intermittent work cycle.

10. A power supply module, characterized in that, The power module includes a voltage conversion circuit and a control circuit as described in any one of claims 1-7, wherein the control circuit is used to control the voltage conversion circuit.

11. A charging pile, characterized in that, It includes a plurality of power modules as described in claim 10 and one or more charging guns, wherein the plurality of power modules are connected to the one or more charging guns for supplying power to the one or more charging guns.

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