Ripple suppression method, system and device and computer program product

Abstract

The invention provides a ripple suppression method, system and device and a computer program product, and relates to the technical field of automobiles. According to the method, in a two-stage topology vehicle-mounted charging circuit composed of a PFC circuit and a DCDC circuit, the ripple suppression is carried out through the collected alternating current and alternating current voltage input by the alternating current side of the PFC circuit and the collected direct current voltage at the output end of the DCDC circuit; according to the method, the pulse of the theoretical output current at the output end of the DCDC circuit is obtained, the corresponding gain compensation coefficient is obtained through the obtained pulse of the theoretical output current, and the gain compensation coefficient is superposed to the given value of a current loop during charging output, so that the actual output current output by the DCDC circuit is dynamically adjusted. Therefore, the ripple current transmitted in the PFC bus is suppressed. Under the condition of not additionally adding a hardware structure, the ripple current transmitted in the PFC bus is suppressed, the hardware volume of the whole circuit can be reduced, and the working efficiency of the vehicle-mounted charging circuit is improved.

Description

Technical Field

[0001] This application relates to the field of automotive technologies, and particularly to a ripple suppression method, system, device, and computer program product. Background Art

[0002] In the prior art, a vehicle-mounted charging circuit with a two-stage topology is usually composed of a power factor correction (PFC) circuit integrated with a rectifier circuit and a high-voltage DCDC circuit. Among them, the AC side of the PFC circuit is used to connect to an AC power supply, and the output end of the DCDC circuit is used to connect to a DC load. Through the above structure, power supply to the DC load from the AC power supply can be achieved. Since the PFC circuit rectifies the alternating current, the PFC circuit will generate power double-frequency pulsation, that is, double-frequency ripple current, and the ripple current will affect the working efficiency of the vehicle-mounted charging circuit.

[0003] In view of the above situation, a relatively large bus electrolytic capacitor can be set on the PFC bus between the PFC circuit and the DCDC circuit for decoupling and filtering to eliminate the ripple. However, the electrolytic capacitor requires a large capacitance value, has a short service life, high cost, and poor dynamic performance, and can no longer meet the requirements of the electric vehicle industry for more compact and more stable vehicle-mounted charging circuit design. Summary of the Invention

[0004] The main purpose of this application is to provide a ripple suppression method, system, device, and computer program product, aiming to solve the technical problem of how to reduce the ripple current transmitted in the PFC bus of the vehicle-mounted charging circuit without additionally increasing the hardware structure.

[0005] To achieve the above purpose, this application provides a ripple suppression method, which is applied to a vehicle-mounted charging circuit composed of a PFC circuit and a DCDC circuit. The AC side of the PFC circuit is connected to an AC power supply, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through a PFC bus, and the output end of the DCDC circuit is connected to a DC load. The ripple suppression method includes:

[0006] Collect the AC input voltage and AC input current on the AC side of the PFC circuit, and collect the DC output voltage output by the DCDC circuit;

[0007] Based on the AC input voltage, the AC input current, and the DC output voltage, obtain the pulsation of the theoretical output current output by the DCDC circuit;

[0008] Obtain the corresponding gain compensation coefficient according to the pulsation of the theoretical output current, and superimpose the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

[0009] In one embodiment, the step of obtaining the pulsation of the theoretical output current of the DCDC circuit based on the AC input voltage, the AC input current, and the DC output voltage includes:

[0010] Based on the AC input voltage and the AC input current, obtain the instantaneous AC input power on the AC side;

[0011] Based on the instantaneous AC input power and the DC output voltage, obtain the pulsation of the theoretical output current of the DCDC circuit.

[0012] In one embodiment, the step of obtaining the pulsation of the theoretical output current of the DCDC circuit based on the instantaneous AC input power and the DC output voltage includes:

[0013] Extract the double-frequency AC power pulsation from the instantaneous AC input power through a resonant filter;

[0014] Divide the double-frequency AC power pulsation by the DC output voltage to obtain the pulsation of the theoretical output current.

[0015] In one embodiment, the step of obtaining the corresponding gain compensation coefficient according to the pulsation of the theoretical output current, superimposing the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus includes:

[0016] Superimpose the gain compensation coefficient on the target output current given by the current loop during charging output to obtain the compensated target output current;

[0017] Collect the actual output current output by the DCDC circuit;

[0018] Generate a corresponding control signal according to the target output current and the actual output current, and based on the control signal, adjust the actual output current of the DCDC circuit to make the actual output current infinitely approach the target output current.

[0019] In addition, to achieve the above object, the present application further provides a ripple suppression system, which is applied to a vehicle-mounted charging circuit composed of a PFC circuit and a DCDC circuit. The AC side of the PFC circuit is connected to an AC power supply, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through a PFC bus, the output end of the DCDC circuit is connected to a DC load, and the ripple suppression system includes:

[0020] An electrical parameter acquisition module, configured to acquire the AC input voltage and AC input current on the AC side of the PFC circuit, and acquire the DC output voltage output by the DCDC circuit;

[0021] A theoretical output current ripple estimation module, configured to obtain the ripple of the theoretical output current output by the DCDC circuit based on the AC input voltage, the AC input current, and the DC output voltage;

[0022] A current regulation module, configured to obtain a corresponding gain compensation coefficient according to the ripple of the theoretical output current, and superimpose the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

[0023] Further, in this embodiment, the theoretical output current ripple estimation module includes:

[0024] An AC input power calculation unit, configured to obtain the instantaneous AC input power on the AC side based on the AC input voltage and the AC input current;

[0025] A ripple extraction unit, configured to obtain the ripple of the theoretical output current output by the DCDC circuit based on the instantaneous AC input power and the DC output voltage.

[0026] Further, in this embodiment, the ripple extraction unit is specifically configured to:

[0027] Extract the double-frequency AC power ripple from the instantaneous AC input power through a resonant filter;

[0028] Divide the double-frequency AC power ripple by the DC output voltage to obtain the ripple of the theoretical output current.

[0029] Further, in this embodiment, the current regulation module is specifically configured to:

[0030] Superimpose the gain compensation coefficient on the target output current given by the current loop during charging output to obtain a compensated target output current;

[0031] Acquire the actual output current currently output by the DCDC circuit;

[0032] Generate a corresponding control signal based on the target output current and the actual output current, and based on the control signal, adjust the actual output current of the DCDC circuit so that the actual output current of the DCDC approaches the target output current infinitely.

[0033] Further, in this embodiment, the present application also provides a ripple suppression device. The ripple suppression device includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is executed by the processor, the steps of the ripple suppression method described above are implemented.

[0034] In addition, to achieve the above object, the present application also provides a computer program product. The computer program product includes a computer program. When the computer program is executed by a processor, the steps of the ripple suppression method described above are implemented.

[0035] The present application provides a ripple suppression method, system, device, and computer program product. The steps of the ripple suppression method include: collecting the AC input voltage and AC input current on the AC side of the PFC circuit, and collecting the DC output voltage output by the DCDC circuit; based on the AC input voltage, the AC input current, and the DC output voltage, obtaining the pulsation of the theoretical output current output by the DCDC circuit; obtaining a corresponding gain compensation coefficient according to the pulsation of the theoretical output current, and superimposing the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

[0036] In a vehicle-mounted charging circuit with a two-stage topology composed of a PFC circuit and a DCDC circuit, by collecting the AC current and AC voltage input on the AC side of the PFC circuit and the DC voltage at the output end of the DCDC circuit, obtaining the pulsation of the theoretical output current at the output end of the DCDC circuit, and then obtaining a corresponding gain compensation coefficient according to the obtained pulsation of the theoretical output current, and superimposing the gain compensation coefficient on the given value of the current loop during charging output, so as to realize dynamic adjustment of the actual output current output by the DCDC circuit, thereby realizing suppression of the ripple current transmitted in the PFC bus. Without adding additional hardware structures, suppressing the ripple current transmitted in the PFC bus can reduce the hardware volume of the entire circuit and improve the working efficiency of the vehicle-mounted charging circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0038] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a schematic flowchart provided for the first embodiment of the ripple suppression method of the present application;

[0040] Figure 2 It is a schematic topological structure diagram of a conventional in-vehicle charging circuit;

[0041] Figure 3 It is a schematic working flowchart of an in-vehicle charging circuit example of the present application;

[0042] Figure 4 It is a schematic flowchart provided for the second embodiment of the ripple suppression method of the present application;

[0043] Figure 5 It is a schematic flowchart provided for the third embodiment of the ripple suppression method of the present application;

[0044] Figure 6 It is a schematic module structure diagram of the ripple suppression system of the embodiments of the present application;

[0045] Figure 7 It is a schematic structure diagram of the ripple suppression device of the embodiments of the present application.

[0046] The realization of the purpose, functional features, and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. Specific Embodiments

[0047] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0048] To better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings of the specification and the specific embodiments.

[0049] The present application proposes a ripple suppression method for the first embodiment, which is applied to an in-vehicle charging circuit composed of a PFC circuit and a DCDC circuit. The AC side of the PFC circuit is connected to an AC power supply, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through a PFC bus, and the output end of the DCDC circuit is connected to a DC load. Please refer to Figure 1 , and the ripple suppression method includes steps S10 - S30:

[0050] Step S10, collect the AC input voltage and AC input current on the AC side of the PFC circuit, and collect the DC output voltage output by the DCDC circuit;

[0051] It should be noted that the execution subject of this embodiment can be a ripple suppression system, or a ripple suppression device with data processing, network communication, and program running functions, etc. This embodiment does not make specific limitations on this. The following takes the ripple suppression system as the execution subject as an example to illustrate this embodiment and the following embodiments.

[0052] It should be understood that, please combine Figure 2 to understand that the technical solution proposed in this application is mainly applied to an on-board charging circuit (On Board Charger, OBC) with a two-stage topology structure composed of a PFC circuit and a DCDC circuit. In this circuit, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through the PFC bus; the AC side of the PFC circuit constitutes the input and is connected to the AC power supply; the output end of the DCDC constitutes the output and is connected to the DC load. The PFC circuit can adjust the phase of the AC input current and AC input voltage provided by the AC power supply, so as to correct the power factor and improve the power transmission efficiency. A rectifier circuit can be integrated in the PFC circuit to rectify the alternating current output by the AC power supply, and then transmit the rectified direct current to the DCDC circuit. The DCDC circuit can convert the voltage of the direct current output by the PFC circuit to generate a direct current that meets the required voltage of the DC load, and transmit the direct current to the DC load, so that the DC load can work normally. The DC load can be a DC battery, and through this circuit, the AC power supply can charge the DC battery.

[0053] It is worth noting that since the PFC circuit rectifies the alternating current output by the AC power supply into direct current and then transmits it to the DCDC circuit, and since the AC voltage and current will be adjusted to the same phase, there will be a power double-frequency pulsation in the circuit, and its manifestation is that there is a double-frequency ripple current in the electrical signal output by the DCDC circuit to the DC load. Usually, a bus capacitor filter circuit with a large capacitance value is set between the PFC circuit and the DCDC circuit to filter out the power double-frequency pulsation in the circuit, so as to eliminate the ripple current transmitted in the PFC bus. However, due to the large power fluctuation in actual situations, the bus capacitor usually needs to use an electrolytic capacitor with a large capacitance value and volume, resulting in too large a space volume occupied by the entire circuit and being not conducive to the subsequent upgrade and iteration of the product.

[0054] It should be noted that the technical solution proposed in this application is an improvement based on the above technical solution, and the effect of the ripple current transmitted in the PFC bus can be achieved through the existing hardware structure combined with the software control method. If this technical solution is adopted, the bus capacitor between the PFC circuit and the DCDC circuit can be cancelled, thereby making the space volume of the entire on-vehicle charging circuit smaller. Please combine Figure 3 to understand. In this embodiment, it is necessary to use the first voltage sensor and the first current sensor provided on the AC side of the existing PFC circuit, and the second voltage sensor provided at the output end of the DCDC circuit. Among them, the first voltage sensor can be an AC voltage sensor, the first current sensor can be an AC current sensor, and the second voltage sensor can be a DC voltage sensor. Therefore, the AC input voltage on the AC side of the PFC circuit can be collected by the first voltage sensor, the AC input current on the AC side of the PFC circuit can be collected by the first current sensor, and the DC output voltage at the output end of the DCDC circuit can be collected by the second voltage sensor.

[0055] It should be noted that in this embodiment, the AC input current actually includes the AC current directly output by the AC power supply and the second-harmonic AC current generated by rectification. Correspondingly, the AC input voltage actually includes the AC voltage directly output by the AC power supply and the second-harmonic AC voltage generated by rectification.

[0056] Step S20, based on the AC input voltage, the AC input current, and the DC output voltage, obtain the pulsation of the theoretical output current output by the DCDC circuit;

[0057] It should be noted that in this embodiment, due to energy conservation, it can be assumed that the power second-harmonic pulsation generated by rectification at the PFC circuit will ultimately be completely absorbed by the DC load connected to the output end of the DCDC circuit. Therefore, the total power input on the AC side of the PFC circuit should be approximately equal to the sum of the DC power and the AC power output by the DCDC circuit, and the generated power second-harmonic pulsation is approximately equal to the AC power output by the DCDC circuit. The voltage at the DC load is relatively stable at a certain fixed value. Therefore, it can be considered that the ripple current generated by the power second-harmonic pulsation in the circuit is all reflected in the periodic change of the theoretical output current output to the DC load. That is, the ripple current refers to the second-harmonic current formed on the PFC bus corresponding to the pulsation in the theoretical output current proposed in this embodiment.

[0058] In specific implementation, the total power input on the AC side can be determined through the AC input voltage and AC input current on the AC side, and then the power corresponding to the double-frequency pulse can be extracted from the total power. Subsequently, the pulsation of the theoretical output current existing at the output end of the DCDC circuit can be obtained through the power corresponding to the double-frequency pulse and the DC output voltage output by the DCDC circuit, that is, the ripple current output to the DC load is obtained.

[0059] Step S30, obtain the corresponding gain compensation coefficient according to the pulsation of the theoretical output current, and superimpose the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

[0060] It is easy to understand that after obtaining the pulsation of the theoretical output current, a gain compensation coefficient can be calculated based on the pulsation of the theoretical output current, and the gain compensation coefficient is used to be superimposed on the given value of the current loop. When the PFC circuit performs charging output, the gain compensation coefficient is superimposed on the given value of the current loop during charging output, so as to dynamically adjust the working state of the DCDC circuit, so that the actual output current of the DCDC circuit is dynamically adjusted accordingly, and further perform reverse dynamic compensation on the ripple current transmitted in the PFC bus between the PFC circuit and the DCDC circuit, that is, dynamically suppress the ripple current transmitted in the PFC bus. Based on the above method, the power corresponding to the ripple current in the PFC bus can be transferred to the DC load for absorption, ensuring that the ripple current transmitted in the PFC bus is minimized as much as possible, reducing the energy loss generated when the PFC circuit works, and improving the working efficiency of the PFC circuit.

[0061] The present application provides a ripple suppression method. In a vehicle-mounted charging circuit with a two-stage topology composed of a PFC circuit and a DCDC circuit, by collecting the AC current and AC voltage input on the AC side of the PFC circuit and the DC voltage at the output end of the DCDC circuit, the pulsation of the theoretical output current at the output end of the DCDC circuit is obtained, and then the corresponding gain compensation coefficient is obtained through the obtained pulsation of the theoretical output current, and the gain compensation coefficient is superimposed on the given value of the current loop during charging output to realize dynamic adjustment of the actual output current output by the DCDC circuit, thereby realizing suppression of the ripple current transmitted in the PFC bus. Without additionally increasing the hardware structure, the ripple current transmitted in the PFC bus can be suppressed, the hardware volume of the entire circuit can be reduced, and the working efficiency of the vehicle-mounted charging circuit can be improved.

[0062] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar content as that in the above-mentioned first embodiment can be referred to the above introduction and will not be repeated hereinafter. On this basis, please refer to Figure 4, the step of obtaining the pulsation of the theoretical output current of the DCDC circuit based on the AC input voltage, the AC input current, and the DC output voltage includes:

[0063] Step S21, based on the AC input voltage and the AC input current, obtain the instantaneous AC input power on the AC side;

[0064] It should be noted that, please combine Figure 3 for understanding. In this embodiment, the collected AC input voltage and AC input current can be multiplied by a set multiplier to obtain the instantaneous AC input power on the AC side of the PFC circuit.

[0065] Step S22, based on the instantaneous AC input power and the DC output voltage, obtain the pulsation of the theoretical output current of the DCDC circuit.

[0066] It should be noted that, in this embodiment, the power component with fluctuations generated by rectification that is needed can be extracted from the instantaneous AC input power, and then combined with the collected DC output voltage, the pulsation of the theoretical output current output by the DCDC circuit to the DC load under theoretical conditions can be calculated.

[0067] Further, in this embodiment, the step of obtaining the pulsation of the theoretical output current of the DCDC circuit based on the instantaneous AC input power and the DC output voltage includes:

[0068] Step S221, extract the double-frequency AC power pulsation from the instantaneous AC input power through a resonant filter;

[0069] It should be noted that, in this embodiment, the obtained instantaneous AC input power can be filtered by a set resonant filter in different frequency bands to retain the power with double-frequency fluctuations generated by rectification, that is, the double-frequency AC power pulsation.

[0070] Step S222, divide the double-frequency AC power pulsation by the DC output voltage to obtain the pulsation of the theoretical output current.

[0071] It is easy to understand that, in this embodiment, due to energy conservation, the double-frequency AC power pulsation on the AC side of the PFC circuit is approximately equal to the power corresponding to the AC ripple at the output end of the DCDC circuit. Therefore, a set divider can be used to perform arithmetic processing on the obtained double-frequency AC power pulsation and the collected DC output voltage, so as to obtain the pulsation of the theoretical output current output by the DCDC circuit to the DC load under theoretical conditions.

[0072] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the content that is the same as or similar to the above-mentioned first embodiment and second embodiment can be referred to the above introduction and will not be described in detail hereinafter. On this basis, please refer to Figure 5 , the steps of obtaining a corresponding gain compensation coefficient according to the pulsation of the theoretical output current, superimposing the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit, and suppressing the ripple current in the PFC bus include:

[0073] Step S31, superimposing the gain compensation coefficient on the target output current given by the current loop during charging output to obtain a compensated target output current;

[0074] Step S32, collecting the actual output current output by the DCDC circuit;

[0075] Step S33, generating a corresponding control signal according to the target output current and the actual output current, and based on the control signal, adjusting the actual output current of the DCDC circuit to make the actual output current infinitely approach the target output current.

[0076] It should be noted that, please combine Figure 3 for understanding. In this embodiment, the output end of the DCDC circuit also has a second current sensor for collecting the actual output current output by the DCDC circuit. A current closed-loop controller can be used to adjust the working state of the DCDC circuit. The core of the current closed-loop controller is a PI controller, which can perform operations on the input value through the set proportional term and integral term, thereby generating a corresponding PWM or PFM type control signal and outputting the control signal to the DCDC circuit, so as to control the magnitude of the DC current output by the DCDC circuit, and further control its actual output current.

[0077] It is easy to understand that, in this embodiment, the gain compensation coefficient obtained by calculation can be superimposed and compensated with the originally given target output current through an adder to obtain a compensated target output current. Then, the compensated target output current is used as an input item and put into the error amplifier inside the current closed-loop controller. The error amplifier compares the compensated target output current with the actual output current to obtain the error value between the actual output current and the target output current that should be output to the DC load theoretically. Then, the error value is used as an input item and input into the PI controller, so that the PI controller can generate a corresponding control signal for controlling the working state of the DCDC circuit.

[0078] Among them, the control signal output by the DCDC circuit can be dynamically adjusted based on the error value between the actual output current and the compensated target output current, so that the DCDC circuit can correspondingly adjust the magnitude of its actual output current, making the actual output current infinitely close to the compensated target output current. At this time, the error value between the actual output current and the compensated target output current gradually decreases until it can be ignored. Correspondingly, the ripple current transmitted on the PFC bus decreases as the error value gets smaller.

[0079] An embodiment of the present application also provides a ripple suppression system. Please refer to Figure 6 The ripple suppression system includes:

[0080] An electrical parameter acquisition module 10, configured to acquire the AC input voltage and the AC input current on the AC side of the PFC circuit, and acquire the DC output voltage output by the DCDC circuit;

[0081] A theoretical output current ripple estimation module 20, configured to obtain the ripple of the theoretical output current output by the DCDC circuit based on the AC input voltage, the AC input current, and the DC output voltage;

[0082] A current regulation module 30, configured to obtain a corresponding gain compensation coefficient according to the ripple of the theoretical output current, and superimpose the gain compensation coefficient on the given value of the current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

[0083] Further, in this embodiment, the theoretical output current ripple estimation module 20 includes:

[0084] An AC input power calculation unit 21, configured to obtain the instantaneous AC input power on the AC side based on the AC input voltage and the AC input current;

[0085] A ripple extraction unit 22, configured to obtain the ripple of the theoretical output current output by the DCDC circuit based on the instantaneous AC input power and the DC output voltage.

[0086] Further, in this embodiment, the ripple extraction unit 22 is specifically configured to:

[0087] Extract the double-frequency AC power ripple from the instantaneous AC input power through a resonant filter;

[0088] Divide the double-frequency AC power ripple by the DC output voltage to obtain the ripple of the theoretical output current.

[0089] Further, in this embodiment, the current regulation module 30 is specifically configured to:

[0090] Superimpose the gain compensation coefficient on the target output current given by the current loop during charging output to obtain the compensated target output current;

[0091] Collect the actual output current currently output by the DCDC circuit;

[0092] Generate a corresponding control signal according to the target output current and the actual output current, and based on the control signal, adjust the actual output current of the DCDC circuit so that the actual output current of the DCDC approaches the target output current infinitely.

[0093] The ripple suppression system provided by the embodiments of the present application adopts the ripple suppression method in the above embodiments, and can solve the technical problem of how to reduce the ripple current transmitted in the PFC bus of the on-vehicle charging circuit without additionally increasing the hardware structure. Compared with the prior art, the beneficial effects of the ripple suppression system provided by the embodiments of the present application are the same as those of the ripple suppression method provided by the above embodiments, and other technical features in the ripple suppression system are the same as those disclosed in the above embodiment method, and will not be elaborated here.

[0094] The present application provides a ripple suppression device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the ripple suppression method in the first embodiment above.

[0095] Next, refer to Figure 7 , which shows a schematic structural diagram of a ripple suppression device suitable for implementing the embodiments of the present application. The ripple suppression device in the embodiments of the present application may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (such as in-vehicle navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The shown ripple suppression device is only an example and should not bring any limitation to the functions and usage scope of the embodiments of the present application.

[0096] As Figure 7As shown, the ripple suppression device may include a processing device 1001 (such as a central processing unit, a graphics processing unit, etc.), which may perform various appropriate actions and processes according to a program stored in the read-only memory 1002 or a program loaded from the storage device 1003 into the random access memory 1004. In the random access memory 1004, various programs and data required for the operation of the ripple suppression device are also stored. The processing device 1001, the read-only memory 1002, and the random access memory 1004 are connected to each other through a bus 1005. The input / output interface 1006 is also connected to the bus. Generally, the following systems may be connected to the input / output interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 may allow the ripple suppression device to communicate with other devices wirelessly or wiredly to exchange data. Although the figure shows a ripple suppression device having various systems, it should be understood that it is not required to implement or have all the shown systems. Instead, more or fewer systems may be implemented or had.

[0097] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts may be implemented as computer software programs. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes program codes for performing the methods shown in the flowcharts. In such an embodiment, the computer program may be downloaded and installed from a network through the communication device, or installed from the storage device 1003, or installed from the read-only memory 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments disclosed in the present application are executed.

[0098] The ripple suppression device provided by the present application adopts the ripple suppression method in the above-mentioned embodiment, and can solve the technical problem of how to reduce the ripple current transmitted in the PFC bus of the in-vehicle charging circuit without additionally increasing the hardware structure. Compared with the prior art, the beneficial effects of the ripple suppression device provided by the present application are the same as those of the ripple suppression method provided by the above-mentioned embodiment, and other technical features in the ripple suppression device are the same as those disclosed in the method of the previous embodiment, and will not be elaborated here.

[0099] It should be understood that each part disclosed in this application can be implemented by hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0100] As described above, the above are only specific embodiments of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed in this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

[0101] This application also provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the steps of the ripple suppression method as described above.

[0102] The computer program product provided by this application can solve the technical problem of how to reduce the ripple current transmitted in the PFC bus of the in-vehicle charging circuit without additionally increasing the hardware structure. Compared with the prior art, the beneficial effects of the computer program product provided by this application are the same as those of the ripple suppression method provided in the above embodiments, and will not be elaborated here.

[0103] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, shall be included in the patent scope of this application by the same token.

Claims

1. A ripple suppression method, characterized in that: Applied to an on-board charging circuit composed of a PFC circuit and a DCDC circuit, the AC side of the PFC circuit is connected to an AC power supply, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through a PFC bus, and the output end of the DCDC circuit is connected to a DC load. The steps of the ripple suppression method include: Collecting the AC input voltage and the AC input current of the AC side of the PFC circuit, and collecting the DC output voltage output by the DCDC circuit; Based on the AC input voltage, the AC input current and the DC output voltage, obtaining a pulsation of a theoretical output current output by the DCDC circuit; A corresponding gain compensation coefficient is obtained according to the pulsation of the theoretical output current, and the gain compensation coefficient is superimposed on the given current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

2. The ripple suppression method according to claim 1, characterized in that: The step of obtaining the pulsation of the theoretical output current output by the DCDC circuit based on the AC input voltage, the AC input current and the DC output voltage comprises: Based on the AC input voltage and the AC input current, acquiring the instantaneous AC input power of the AC side; Based on the instantaneous AC input power and the DC output voltage, a pulsation of a theoretical output current output by the DCDC circuit is obtained.

3. The ripple suppression method according to claim 2, characterized in that: The step of obtaining the pulsation of the theoretical output current output by the DCDC circuit based on the instantaneous AC input power and the DC output voltage comprises: extracting double frequency AC power pulsation from the instantaneous AC input power through a resonant filter; The pulsation of the theoretical output current is obtained by dividing the double frequency AC power pulsation by the DC output voltage.

4. The ripple suppression method according to claim 1, characterized in that: The step of obtaining a corresponding gain compensation coefficient according to the pulsation of the theoretical output current, superimposing the gain compensation coefficient on the given current loop during charging output to adjust the actual output current output by the DCDC circuit, and suppressing the ripple current in the PFC bus comprises: The gain compensation coefficient is added to the target output current given by the current loop during charging output to obtain the compensated target output current; Collecting the actual output current output by the DCDC circuit; A corresponding control signal is generated according to the target output current and the actual output current, and based on the control signal, the actual output current of the DCDC circuit is adjusted so that the actual output current infinitely approaches the target output current.

5. A ripple suppression system, characterized in that: Applied to an on-board charging circuit composed of a PFC circuit and a DCDC circuit, the AC side of the PFC circuit is connected to an AC power supply, the DC side of the PFC circuit is connected to the input end of the DCDC circuit through a PFC bus, and the output end of the DCDC circuit is connected to a DC load. The ripple suppression system includes: An electrical parameter acquisition module, used to acquire the AC input voltage and AC input current of the AC side of the PFC circuit, and to acquire the DC output voltage output by the DCDC circuit; a theoretical output current pulsation estimation module, configured to obtain the pulsation of the theoretical output current output by the DCDC circuit based on the AC input voltage, the AC input current and the DC output voltage; The current regulation module is used to obtain a corresponding gain compensation coefficient according to the pulsation of the theoretical output current, and superimpose the gain compensation coefficient on the given current loop during charging output to adjust the actual output current output by the DCDC circuit and suppress the ripple current in the PFC bus.

6. The ripple suppression system according to claim 5, characterized in that: The theoretical output current pulsation estimation module includes: an AC input power calculation unit, configured to obtain the instantaneous AC input power of the AC side based on the AC input voltage and the AC input current; A pulsation extraction unit is used to obtain the pulsation of the theoretical output current output by the DCDC circuit based on the instantaneous AC input power and the DC output voltage.

7. The ripple suppression system according to claim 6, characterized in that: The pulsation extraction unit is specifically used for: extracting double frequency AC power pulsation from the instantaneous AC input power through a resonant filter; The pulsation of the theoretical output current is obtained by dividing the double frequency AC power pulsation by the DC output voltage.

8. The ripple suppression system according to claim 5, characterized in that: The current regulation module is specifically used for: The gain compensation coefficient is added to the target output current given by the current loop during charging output to obtain the compensated target output current; Collecting the actual output current currently output by the DCDC circuit; A corresponding control signal is generated according to the target output current and the actual output current, and based on the control signal, the actual output current of the DCDC circuit is adjusted so that the actual output current of the DCDC circuit is infinitely close to the target output current.

9. A ripple suppression device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, the steps of the ripple suppression method according to any one of claims 1 to 4 are implemented.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the ripple suppression method according to any one of claims 1 to 4 are implemented.

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