Direct current ripple suppression circuit and control method

Abstract

According to the DC ripple suppression circuit and the control method provided by the invention, an adjustable ripple absorption circuit is introduced, so that effective absorption and suppression of ripple current in a DC bus are realized. In the process, the controller calculates the direct-current power based on the collected electric signals, and power output is optimized by adjusting the resistance value of the variable resistor. And when the direct current power reaches the maximum value, the total loss of the whole system is minimum, so that the technical problem that the loss is relatively large when the direct current ripples are suppressed in related technologies is effectively solved, and the overall efficiency and stability of the system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current power systems, and in particular to a direct current ripple suppression circuit and a control method. Background Art

[0002] In a DC power system, as the load changes and the conversion equipment (such as inverters, chargers, etc.) work, ripple voltage and ripple current will be generated in the DC bus. These ripples not only increase the ineffective loss of the system, but also affect the stability and life of the power equipment. Although the traditional ripple absorption method can reduce the ripple, it often introduces large losses in the absorption circuit itself, resulting in a decrease in the overall efficiency of the system. Therefore, how to minimize the system loss while effectively absorbing the ripple, and dynamically adjust the performance of the absorption circuit under different working conditions to achieve the effect of minimum loss, is a technical problem that needs to be solved urgently.

[0003] In the related art, there is a technical problem that the loss is large when suppressing the DC ripple. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies and provide a DC ripple suppression circuit and a control method to solve the technical problem of large loss when suppressing DC ripple in the related art.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a DC ripple suppression circuit connected between a DC bus and a main circuit, comprising: A ripple absorption circuit can be selectively connected to the positive bus and the negative bus of the DC bus; An electrical signal acquisition circuit, electrically connected to the DC bus, for acquiring an electrical signal from the DC bus; The controller is connected to the electrical signal acquisition circuit and the ripple absorption circuit respectively, and is used to control whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0006] Furthermore, the ripple absorption circuit includes: A variable resistor, one end of which is connected to the positive bus of the DC bus, and is used to adjust the magnitude of the current in the DC ripple suppression circuit; An absorption capacitor, one end of which is connected to the other end of the variable resistor, and the other end of the absorption capacitor is connected to the negative bus of the DC bus, for absorbing DC ripple.

[0007] Furthermore, the ripple absorption circuit includes: A switch device, one end of which is connected to the positive bus of the DC bus, and the other end is connected to one end of the variable resistor, and the control end of the switch device is connected to the controller, and is used to selectively connect or disconnect the ripple absorption circuit to or from the DC bus based on an instruction issued by the controller.

[0008] Furthermore, the ripple absorption circuit includes: A discharge resistor is connected in parallel with the absorption capacitor and is used to provide a discharge path for the absorption capacitor after the absorption capacitor is fully charged, so that the absorption capacitor can be discharged in time during the subsequent ripple absorption process.

[0009] Furthermore, the electrical signal acquisition circuit includes: a voltage sampling device and a current sampling device, which are used to collect voltage and current signals of the DC bus respectively.

[0010] Furthermore, the voltage sampling device comprises: A first voltage sampling device, one end of which is connected to the positive bus of the DC bus and is used to collect the positive voltage signal of the DC bus; A second voltage sampling device, one end of which is connected to the negative bus of the DC bus and is used to collect a negative voltage signal of the DC bus; An operational amplifier circuit, whose input end is respectively connected to the other end of the first voltage sampling device and the second voltage sampling device, and whose output end is connected to the controller, is used to process the received positive voltage signal and negative voltage signal and then input them into the controller.

[0011] Furthermore, the operational amplifier circuit comprises: A filter inductor, one end of which is connected to the other end of the first voltage sampling device and the second voltage sampling device respectively, and is used to suppress high-frequency noise in the positive voltage signal and the negative voltage signal; An operational amplifier, whose input end is connected to the other end of the filter inductor, and is used to process the positive voltage signal and the negative voltage signal; The LC filter network is connected in parallel with the operational amplifier and is used to perform filtering processing on the positive voltage signal and the negative voltage signal.

[0012] In a second aspect, the present invention provides a control method for a DC ripple suppression circuit, comprising: Collect the electrical signal of DC bus; According to the electrical signal of the DC bus, control is made to determine whether the ripple absorption circuit is connected to the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0013] Furthermore, the step of controlling whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal includes: Determining whether the ripple absorption circuit needs to be connected to the DC bus; When it is determined that the ripple absorption circuit needs to be connected to the DC bus, the switch device is controlled to close to connect the ripple absorption circuit to the DC bus, so that the ripple absorption circuit absorbs the ripple current in the DC bus.

[0014] Furthermore, the step of determining whether the ripple absorption circuit needs to be connected to the DC bus includes: Determining whether the fluctuation amplitude of the voltage signal of the DC bus satisfies a preset first voltage fluctuation amplitude threshold, and / or determining whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold; When a preset first voltage fluctuation amplitude threshold and / or a preset first current fluctuation amplitude threshold are met, it is determined that the ripple absorption circuit needs to be connected to the DC bus.

[0015] Furthermore, the control method further includes: When the DC power reaches a maximum value, the resistance value of the current ripple absorption circuit is reduced based on the resistance value of the current ripple absorption circuit, thereby improving the absorption capacity of the ripple absorption circuit for the ripple current in the DC bus; Determine whether the fluctuation amplitude of the voltage signal satisfies a preset second voltage fluctuation amplitude threshold, and / or determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset second current fluctuation amplitude threshold; wherein the second voltage fluctuation amplitude threshold is smaller than the first voltage fluctuation amplitude threshold, and the second current fluctuation amplitude threshold is smaller than the first current fluctuation amplitude threshold; When a preset second voltage fluctuation amplitude threshold and / or a preset second current fluctuation amplitude threshold are met, the reduction of the resistance value of the ripple absorption circuit is stopped.

[0016] Beneficial effects: The present invention realizes effective absorption and suppression of ripple current in the DC bus by introducing an adjustable ripple absorption circuit. In this process, the controller calculates the DC power based on the collected electrical signal and optimizes the power output by adjusting the resistance value of the variable resistor. When the DC power reaches the maximum value, the total loss of the entire system is minimized, thereby effectively solving the technical problem of large loss when suppressing DC ripple in the related art and improving the overall efficiency and stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a block diagram of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 2 is a block diagram of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 3 is a block diagram of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 4 is a block diagram of a voltage sampling device provided by an embodiment of the present invention; Figure 5 It is a flow chart of a control method of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 6 It is a flow chart of a control method of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 7 It is a flow chart of a control method of a DC ripple suppression circuit provided by an embodiment of the present invention; Figure 8 is a circuit diagram of a DC ripple suppression circuit provided by an embodiment of the present invention; Fig. 9 is a circuit diagram of a DC ripple suppression circuit provided by an embodiment of the present invention; Fig.10 It is a block diagram of an electronic device used in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0019] Overview: DC power systems are widely used in photovoltaic power generation systems, energy storage systems, electric vehicles and other fields. In these systems, the DC bus is used to transmit electrical energy, and in theory the DC voltage should remain constant. However, in actual working environments, due to changes in system load and the operation of power conversion equipment (such as inverters, DC-DC converters, etc.), fluctuations in DC voltage and current will occur, which are usually manifested as ripple voltage and ripple current.

[0020] Ripple current can bring many negative effects. First, ripple current will increase the reactive power of the system, thereby reducing the energy transmission efficiency of the system. Second, ripple current may also increase the temperature rise of power equipment, shorten the service life of electronic components, and even cause system instability in some sensitive equipment. Therefore, how to suppress and absorb these ripples has become an important issue in designing efficient DC power systems.

[0021] In related technologies, ripple suppression technology mainly relies on introducing an absorption circuit in the DC bus to absorb the ripple current through absorption capacitors. However, although these absorption methods can reduce the ripple to a certain extent, the absorption circuit itself also consumes energy, especially under high-power conditions, the loss generated by the absorption circuit may be large, which in turn leads to a decrease in the overall efficiency of the system.

[0022] In addition, the absorption circuit in the related art often uses a fixed resistance resistor. Under different working conditions, the resistance cannot be dynamically adjusted according to the actual ripple conditions, so it is impossible to effectively balance the absorption effect and energy loss of the system. Especially under conditions with large load changes or high power conditions, the fixed resistance absorption circuit often has difficulty in coping with complex ripple changes, resulting in increased system losses.

[0023] Therefore, in the related art, there is a technical problem that the loss is large when suppressing the DC ripple.

[0024] Example This embodiment provides a DC ripple suppression circuit, connected between a DC bus and a main circuit, including: The ripple absorption circuit can be selectively connected to the positive bus and the negative bus of the DC bus.

[0025] In a specific embodiment, the ripple absorption circuit may include: A variable resistor, one end of which is connected to the positive bus of the DC bus, is used to adjust the magnitude of the current in the DC ripple suppression circuit.

[0026] In this embodiment, the variable resistor can be represented as a resistor element whose resistance value can be adjusted by mechanical or electronic means. In the DC ripple suppression circuit, the variable resistor is connected to the positive bus of the DC bus, and plays a role in adjusting the current size in the DC ripple suppression circuit. The resistance value of the variable resistor can be increased or decreased by real-time adjustment of the controller, which will directly affect the current flow in the DC ripple suppression circuit, and then adjust the absorption efficiency of the DC bus ripple current. Specifically: when the resistance value of the variable resistor increases, the current of the DC ripple suppression circuit decreases, and the effect of absorbing the ripple current is weakened; when the resistance value of the variable resistor decreases, the current of the DC ripple suppression circuit increases, absorbing more ripple current, thereby suppressing the fluctuation of the ripple voltage.

[0027] In a specific embodiment, the ripple absorption circuit may include: An absorption capacitor, one end of which is connected to the other end of the variable resistor, and the other end of the absorption capacitor is connected to the negative bus of the DC bus, for absorbing DC ripple.

[0028] In a specific embodiment, the ripple absorption circuit may include: A switch device, one end of which is connected to the positive bus of the DC bus, and the other end is connected to one end of the variable resistor, and the control end of the switch device is connected to the controller, and is used to selectively connect or disconnect the DC ripple suppression circuit to or from the DC bus based on an instruction issued by the controller.

[0029] In this embodiment, the switch device may be a relay. It is understood that a relay is an electrical control device that uses electromagnetic principles to achieve automatic control of a switch. A relay may be composed of a coil, a contact, a spring, and other parts. When the coil is energized, the generated magnetic field will attract the contact to achieve the connection or disconnection of the circuit. When the controller sends a signal, the coil of the relay is energized, the contact is closed, and the DC ripple suppression circuit is connected to the DC bus; when the control signal is disconnected, the contact is disconnected, and the DC ripple suppression circuit is disconnected from the DC bus.

[0030] The DC ripple suppression circuit may further include: The electric signal acquisition circuit is electrically connected to the DC bus and is used to acquire the electric signal of the DC bus.

[0031] In a specific implementation, the electrical signal acquisition circuit includes: a voltage sampling device and a current sampling device, which are used to respectively acquire voltage and current signals of the DC bus.

[0032] In a specific embodiment, the voltage sampling device comprises: A first voltage sampling device has one end connected to the positive bus of the DC bus and is used to collect a positive voltage signal of the DC bus.

[0033] The second voltage sampling device has one end connected to the negative bus of the DC bus and is used to collect the negative voltage signal of the DC bus.

[0034] An operational amplifier circuit, whose input end is respectively connected to the other end of the first voltage sampling device and the second voltage sampling device, and whose output end is connected to the controller, is used to process the received positive voltage signal and negative voltage signal and then input them into the controller.

[0035] In a specific embodiment, the operational amplifier circuit includes: A filter inductor, one end of which is connected to the other end of the first voltage sampling device and the second voltage sampling device respectively, and is used to suppress high-frequency noise in the positive voltage signal and the negative voltage signal; An operational amplifier, whose input end is connected to the other end of the filter inductor, and is used to process the positive voltage signal and the negative voltage signal; The LC filter network is connected in parallel with the operational amplifier and is used to perform filtering processing on the positive voltage signal and the negative voltage signal.

[0036] The controller is connected to the electrical signal acquisition circuit and the ripple absorption circuit respectively, and is used to control whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0037] like Figure 1 As shown, this embodiment provides a DC ripple suppression circuit, which can be selectively connected to a DC bus, and the DC bus is used to power a main circuit.

[0038] Specifically, the main circuit can be represented as a closed power transmission circuit formed by a DC bus, in which electric energy is transmitted from the power source to the load through an energy conversion module (e.g., an inverter circuit, a rectifier circuit, and a DC-DC conversion circuit, etc.), and after being consumed by the load or stored in an energy storage device, returns to the power source to form an energy closed loop. The main circuit may include: a load powered by a DC bus, a module that performs energy conversion, and a core circuit that performs functions such as energy storage and protection.

[0039] In a photovoltaic power generation system, the main circuit can be a closed power loop from the photovoltaic panel to the load or the grid. More specifically, the photovoltaic panel generates direct current, which is collected to the DC bus through the DC combiner box. The electric energy passes through the photovoltaic inverter to convert the DC power into alternating current (if it is supplied to the AC load or connected to the grid), or directly adjusts the voltage through the DC-DC converter (if it is supplied to the DC load). The converted electric energy flows to the load (such as household electricity, industrial equipment, etc.) or the grid (if it is connected to the grid for power generation), forming a closed loop of energy transmission.

[0040] In the energy storage system, the main circuit can be a closed power circuit formed during the charging and discharging process, in which the electric energy of the battery pack flows to the load or the grid through the bidirectional DC-DC converter and the inverter. More specifically, the battery pack stores electric energy, which is transmitted to the load or the grid through the DC bus. When the battery pack is discharged, the electric energy passes through the bidirectional DC-DC converter to adjust the voltage to meet the load requirements. If the load is an AC device, the electric energy can also be converted from DC to AC through a bidirectional inverter to supply the AC load or be incorporated into the grid. When charging, the electric energy enters the DC bus from the grid or renewable energy (such as photovoltaics and wind energy) through an inverter or a DC-DC converter, and is charged into the battery pack to complete the energy circuit.

[0041] The DC ripple suppression circuit may include: A variable resistor, one end of which is connected to the positive bus of the DC bus, is used to adjust the magnitude of the current in the DC ripple suppression circuit.

[0042] In this embodiment, the variable resistor can be represented as a resistor element whose resistance value can be adjusted by mechanical or electronic means. In the DC ripple suppression circuit, the variable resistor is connected to the positive bus of the DC bus, and plays a role in adjusting the current size in the DC ripple suppression circuit. The resistance value of the variable resistor can be increased or decreased by real-time adjustment of the controller, which will directly affect the current flow in the DC ripple suppression circuit, and then adjust the absorption efficiency of the DC bus ripple current. Specifically: when the resistance value of the variable resistor increases, the current of the DC ripple suppression circuit decreases, and the effect of absorbing the ripple current is weakened; when the resistance value of the variable resistor decreases, the current of the DC ripple suppression circuit increases, absorbing more ripple current, thereby suppressing the fluctuation of the ripple voltage.

[0043] In this embodiment, the variable resistor may be a digitally controllable resistor. It is understood that a digitally controllable resistor is an electronic component whose resistance is controlled by a digital signal and can be connected to a controller via a digital communication protocol (eg, I²C or SPI).

[0044] In this embodiment, the variable resistor may be a programmable resistor. It is understood that the programmable resistor can adjust the resistance value in real time through the instruction of the controller, so as to accurately control the current size in the DC ripple suppression circuit.

[0045] In this embodiment, the variable resistor may also be a MOSFET (field effect transistor). Specifically, the current between the source (Source) and the drain (Drain) can be adjusted by the gate control signal, which is equivalent to a variable resistor. It is understandable that the resistance adjustment of the MOSFET is achieved by controlling the gate voltage, which can play a role in dynamically adjusting the current size in the DC ripple suppression circuit. The on-resistance of the MOSFET can be changed in real time through the signal output by the controller to achieve precise control of the current.

[0046] In this embodiment, the variable resistor may also be an IGBT (insulated gate bipolar transistor). Specifically, by controlling the gate drive signal, the IGBT can also adjust the magnitude of the output current.

[0047] In this embodiment, the variable resistor may also be an electronic load.

[0048] An absorption capacitor, one end of which is connected to the other end of the variable resistor, and the other end of the absorption capacitor is connected to the negative bus of the DC bus, for absorbing DC ripple.

[0049] In this embodiment, in the DC ripple suppression circuit, one end of the absorption capacitor is connected to the other end of the variable resistor, and the other end is connected to the negative bus of the DC bus to form an absorption loop. When there is a ripple current in the DC bus of the circuit, the absorption capacitor uses its charge storage capacity to store excess electric energy when the ripple current arrives, and releases the charge after the fluctuation disappears, thereby effectively suppressing voltage fluctuations and making the DC voltage smoother.

[0050] It is understandable that the absorption capacitor can be used to absorb high-frequency ripples and noise, reduce the amplitude of fluctuations, and smooth the voltage. When the DC bus voltage rises, the absorption capacitor stores energy by charging. When the voltage drops, the absorption capacitor releases energy to maintain voltage stability. When there is a ripple voltage in the DC power supply output, the absorption capacitor can effectively absorb these ripple currents, reduce voltage fluctuations, and thus improve the overall stability of the DC power system. Since the absorption capacitor can respond quickly to voltage fluctuations, it can effectively suppress higher frequency ripples.

[0051] In this embodiment, when the variable resistor is a programmable resistor, one end of the absorption capacitor is connected to the other end of the programmable resistor, and one end of the programmable resistor is connected to the positive bus of the DC bus. The other end of the absorption capacitor is connected to the negative bus of the DC bus to form an absorption loop. The programmable resistor can adjust its resistance value according to the instruction of the controller, thereby changing the current size in the absorption loop and controlling the charging and discharging behavior of the absorption capacitor.

[0052] In this embodiment, when the variable resistor is a MOSFET, one end of the absorption capacitor is connected to the drain of the MOSFET, and the source of the MOSFET is connected to the negative bus of the DC bus. The gate of the MOSFET adjusts its control signal through the controller to adjust the resistance value between the source and the drain. The controller changes the resistance value between the drain and the source by adjusting the gate voltage of the MOSFET to control the current passing through the absorption capacitor in the absorption loop. The absorption capacitor absorbs the ripple current in the DC bus. When ripples appear, the MOSFET adjusts the current size to ensure that the absorption capacitor smoothes the voltage fluctuations.

[0053] In this embodiment, when the variable resistor is an IGBT, one end of the absorption capacitor is connected to the collector of the IGBT, and the emitter of the IGBT is connected to the negative bus of the DC bus. The gate of the IGBT is adjusted by the controller signal to control the on and off of the IGBT, thereby adjusting the current in the absorption loop. In a possible implementation, the controller can adjust the gate signal of the IGBT according to the change of the DC power to control the current flow between the collector and the emitter. The absorption capacitor realizes dynamic current regulation through the IGBT to suppress the ripple voltage.

[0054] In this embodiment, when the variable resistor is an electronic load, one end of the absorption capacitor is connected to the input end of the electronic load, and the other end of the electronic load is connected to the negative bus of the DC bus. The electronic load adjusts its load size through the controller signal, thereby being equivalent to an adjustable resistor to control the current in the absorption loop.

[0055] The voltage sampling device and the current sampling device are used to collect the voltage and current signals of the DC bus respectively.

[0056] In this embodiment, the current sampling device can collect the current signal of the DC bus and transmit it to the controller.

[0057] In this embodiment, the current sampling device may be a Hall effect current sensor. The Hall effect current sensor can detect the current passing through the conductor and sense the magnitude of the current through a magnetic field. It is understood that the Hall effect current sensor can be installed around the positive busbar of the DC bus in a non-contact manner. The measurement can be performed by sensing the magnetic field generated by the current of the positive busbar.

[0058] In this embodiment, the current sampling device may be a shunt resistor. It is understood that the shunt resistor is a precision resistor with a low resistance value, which can be connected in series to the DC bus. The current passing through the DC bus can be indirectly calculated by measuring the voltage drop across the shunt resistor.

[0059] In this embodiment, the current sampling device may be an integrated circuit current sensor. It is understandable that the integrated current sensor chip has a built-in high-precision current measurement circuit, which can collect the current signal of the DC bus.

[0060] In this embodiment, the voltage sampling device can collect the voltage signal of the DC bus.

[0061] In this embodiment, the voltage sampling device can be a voltage-dividing resistor circuit. Specifically, the voltage-dividing resistor circuit can be two precision resistors connected in series to form a voltage-dividing resistor circuit. The high voltage of the DC bus passes through the voltage-dividing resistor circuit, and the voltage is divided into a smaller proportion, and this smaller voltage can be safely sent to the controller for measurement. More specifically, one resistor can be connected to the positive pole of the DC bus, and the other resistor can be connected to the negative pole of the DC bus. The connection midpoint of the two resistors is the sampling node, and the voltage signal of the sampling node is transmitted to the controller for measurement after voltage division.

[0062] In this embodiment, the voltage sampling device may be an isolation amplifier circuit. Specifically, the input end of the isolation amplifier circuit may be connected to the positive pole of the DC bus. The bus voltage is measured. The output end is isolated from the controller circuit and outputs a low voltage signal. In this way, the DC bus voltage can be sampled in real time without destroying the electrical isolation.

[0063] In this embodiment, the voltage sampling device may also be a voltage sampling integrated circuit, which can process the measured voltage signal through internal voltage division and amplification, convert it into a digital signal through a built-in ADC, and then send the measurement result to the controller through a digital communication interface.

[0064] The voltage and current signals may be analog signals or digital signals. It is understandable that the voltage sampling device (e.g., a voltage divider resistor circuit) may directly collect voltage signals from the DC bus, and output an analog voltage signal after voltage division or other processing. The analog signal is proportional to the voltage of the DC bus and is a continuous voltage change value. For example, when the DC bus voltage is 400V, the analog signal output by the voltage divider resistor circuit may be in the range of 0 to 5V. The analog signal is directly transmitted to the analog-to-digital converter (ADC) of the controller, and the controller converts it into a digital signal for processing. The current sampling device (e.g., a Hall effect current sensor) directly collects signals from the current of the DC bus and outputs an analog current signal.

[0065] In some embodiments, a voltage sampling device (e.g., a voltage sensor with a built-in ADC or a digital voltage sensor) can directly convert an analog voltage signal into a digital signal output. The digital signal can be transmitted to the controller via a communication protocol. A digital signal is a quantized voltage value that can be expressed as a binary number, and the controller can directly read these digital signals without going through an analog-to-digital conversion process. A digital current sensor (e.g., a Hall effect sensor with a built-in ADC) can convert the detected current signal into a digital signal output. The digital current signal can also be directly transmitted to the controller via a communication protocol.

[0066] A controller, which is at least respectively connected to the variable resistor, the current sampling device and the voltage sampling device, can calculate the DC power of the DC bus based on the voltage and current signals, and adjust the resistance value of the variable resistor based on the change of the DC power, so that when the DC power reaches a maximum value, the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0067] In a DC power system, maximizing DC power means that the system's power conversion efficiency is the highest and the total loss of the entire circuit is minimized. DC power is the product of the system's voltage and current, representing the effective power delivered by the circuit to the load. When the DC power reaches its maximum value, it means that the voltage and current fluctuations are minimal, the energy loss in the system is minimal, and more power is effectively utilized rather than dissipated in losses. Total loss is a manifestation of reactive power. Total loss includes the losses of the DC ripple suppression circuit and the main circuit, which are mainly derived from the reactive power in the circuit (for example, losses caused by resistor heating, ripple current, etc.). When the DC power is maximum, it means that the reactive power is minimum, the effective energy utilization rate of the system is the highest, and then the total loss of the DC ripple suppression circuit and the main circuit is minimized. When the variable resistor is adjusted to the optimal point, the current and voltage fluctuations (ripples) are most effectively suppressed, and the DC voltage tends to be stable. In this case, the additional power loss caused by the ripple current in the system (such as electromagnetic loss or resistor heat loss caused by current fluctuations) is reduced, thereby minimizing the total loss.

[0068] In this embodiment, the controller may be connected to the variable resistor to output a control signal to the variable resistor to adjust the resistance value of the variable resistor.

[0069] In this embodiment, the controller may be connected to the current sampling device and the voltage sampling device to receive voltage and current signals transmitted by the current sampling device and the voltage sampling device.

[0070] In this embodiment, the controller can calculate the DC power of the DC bus based on the collected voltage and current signals using the formula P=U×I (power=voltage×current). By continuously collecting power, the controller can analyze the power change and decide how to adjust the resistance of the variable resistor to optimize the energy efficiency of the circuit. The controller can dynamically adjust the resistance of the variable resistor according to the power calculation result to maximize the DC power. At this time, the total loss is minimized and the ripple suppression effect is optimal. This process controller can send a control signal (for example, a PWM signal or a digital control signal) to the variable resistor (for example, MOSFET, IGBT, electronic load, etc.) to adjust its resistance value. The controller can also continuously monitor the voltage and current signals through closed-loop feedback control and dynamically adjust the resistance of the variable resistor to maintain the stability of the DC bus and the ripple suppression effect under changing working conditions. Specifically, first, the controller can collect the voltage and current signals transmitted by the voltage sampling device and the current sampling device through an ADC or a digital communication interface. Then, the controller can calculate the DC power of the current DC bus according to the formula P=U×I. Finally, the controller can adjust the resistance of the variable resistor based on the change of DC power to keep the DC power system running when the DC power is maximized.

[0071] In this embodiment, the maximum value can be expressed as the maximum effective power that the DC power system can achieve. When the controller controls the voltage and current fluctuations of the DC bus by adjusting the variable resistor, the system will enter a power optimum point, that is, a state where the DC power is maximized. In this state, the total loss in the system (including the loss of the DC ripple suppression circuit and the main circuit) is minimized.

[0072] Specifically, the maximum value may be a preset maximum value. The preset maximum value may be a fixed value. The preset maximum value may be obtained by experiment or simulation calculation. For example, multiple experiments may be conducted on the DC power system, and the variable resistor, absorption capacitor and other parameters in the system may be adjusted to find the power peak of the system under different working conditions. After recording these peak powers, these values ​​may be stored in the controller as preset maximum values. The voltage fluctuation and current change of the DC bus may be simulated by performing circuit simulation on the entire circuit. Through the simulation tool, the maximum power output point of the system may be found and stored in the controller as a preset value.

[0073] Specifically, the maximum value may be a maximum value obtained through real-time calculation. The maximum value obtained through real-time calculation is adjusted by the controller according to the collected voltage and current signals through dynamic feedback and optimization algorithm during operation until the DC power is maximized. Therefore, in this case, the maximum value is not fixed, but changes continuously according to the real-time operation of the DC power system. More specifically, the controller can continuously collect the voltage and current of the DC bus through the voltage sampling device and the current sampling device to calculate the current DC power. The controller can change the current size of the absorption circuit by adjusting the resistance value of the variable resistor, thereby affecting the voltage fluctuation of the DC bus. The controller can detect the change of DC power after each adjustment through closed-loop feedback control. If the DC power increases, continue to adjust the variable resistor. If the DC power decreases, adjust the opposite direction until the DC power reaches the peak value.

[0074] In this embodiment, the controller may be preset with a linear control algorithm (e.g., PID control algorithm) or an advanced optimization algorithm (e.g., particle swarm algorithm, ant colony algorithm) to dynamically optimize the resistance of the variable resistor to ensure that the DC power system achieves minimum loss under different operating conditions.

[0075] The loss of the DC ripple suppression circuit can be expressed as the loss caused by the DC ripple suppression circuit itself. It is understandable that in order to absorb ripple current and voltage fluctuations to stabilize the DC bus, the DC ripple suppression circuit often needs to introduce some components to achieve this purpose. For example, absorption capacitors, control switches, etc. These components will generate different types of losses during operation.

[0076] Specifically, the losses of the DC ripple suppression circuit may include: Losses in variable resistors: The main function of variable resistors is to adjust the current in the absorption loop so that the ripple current can be effectively absorbed. However, when the current passes through the variable resistor, according to Joule's law, part of the energy will be dissipated in the form of heat, forming heat loss. This loss is calculated by the formula P=I²R, where I is the current passing through the variable resistor and R is the resistance of the variable resistor. When the controller adjusts the resistance of the variable resistor to reduce fluctuations, the change in resistance directly affects the current size and loss. A higher resistance value will limit the current passing through and reduce current loss, but it may not be enough to absorb the ripple. A lower resistance value will allow more current to pass, which may increase the ripple absorption effect, but also increase the heat loss. Therefore, it is necessary to find a balance point of resistance value to effectively absorb ripple while minimizing losses.

[0077] Losses of the absorption capacitor: It is understandable that the main function of the absorption capacitor is to absorb the ripple current through charging and discharging, and smooth the voltage fluctuations of the DC bus. However, the absorption capacitor will generate a certain equivalent series resistance loss during the charging and discharging process. The equivalent series resistance causes a part of the electrical energy to be dissipated as heat in the absorption capacitor, especially in frequent charge and discharge cycles. When the ripple current frequency is high, the charge and discharge rate of the absorption capacitor will also increase, resulting in more energy loss. Therefore, the equivalent series resistance value of the absorption capacitor and the size of the absorption capacitor directly affect the degree of loss. A larger absorption capacitor can better smooth the voltage fluctuations, but it will also bring greater charging and discharging losses.

[0078] Switching device loss: The switching device is used to connect the absorption circuit to the DC bus. The switching device will generate certain switching losses when it is turned on or off, especially the conduction loss during the switching process.

[0079] Discharge resistor loss: In some cases, a discharge resistor may be set in the DC ripple suppression circuit. The discharge resistor is connected in parallel across the absorption capacitor to provide a discharge path for the absorption capacitor when it is not working, preventing the absorption capacitor from remaining charged for a long time. When the absorption capacitor discharges through the discharge resistor, some of the electrical energy will be dissipated in the discharge resistor.

[0080] It is understood that the main circuit is the core circuit of the entire power system, connecting the load and the power supply. The losses of the main circuit can include: Losses caused by ripple current: The ripple current in the DC bus refers to the AC component contained therein. When the ripple current is conducted in the main circuit, it will cause additional losses in the equipment and wires. In particular, high-frequency ripple will cause skin effect in the conductor, increase the effective resistance of the wire, and cause more heat loss. Ripple current will also generate electromagnetic interference, affecting the normal operation of surrounding electronic equipment. In order to reduce this interference, additional filters or shielding devices are usually required, which will also increase the losses in the main circuit.

[0081] Losses of inductance components: If there are inductance components in the main circuit, the inductance will generate iron loss and copper loss when conducting high-frequency ripple current. Iron loss is due to the hysteresis loss and eddy current loss of the iron core caused by the high-frequency magnetic field; copper loss is the heat loss caused by the resistance of the wire in the inductor coil. In particular, high-frequency ripple will significantly increase these losses. The presence of high-frequency ripple will significantly increase the iron loss and copper loss in the inductor, because the high-frequency current will produce a higher current density and skin effect in the wire, which causes the temperature of the inductor component to rise and consume more energy.

[0082] Losses in load devices: Load devices in the main circuit (e.g., inverters, motors, batteries, etc.) will also reduce efficiency due to ripple current and voltage fluctuations. Most load devices are designed to work based on a stable DC power supply. When there are voltage and current fluctuations, the power devices in the device (e.g., IGBT, MOSFET) may operate in a suboptimal state, increasing switching losses and conduction losses. Load devices are highly sensitive to voltage and current, especially when the fluctuation amplitude is large, the power conversion efficiency in the load device will be reduced, increasing the loss of the load device itself.

[0083] Therefore, when the DC power reaches the maximum value, it means that the proportion of effective power in the system transferred to the load is the largest, and the energy loss in the system (such as resistance heat loss, ripple current loss) is the smallest. The ineffective power in the system (such as heating loss, conduction loss, etc.) is minimized, which directly reduces the total loss of the DC ripple suppression circuit and the main circuit. When the variable resistor is dynamically adjusted, the maximum value of the DC power means that the system is operating in the optimal state. At this time, the ripple current and voltage fluctuations are the smallest, and the stability and reliability of the system are also the highest. Therefore, finding the maximum value of the DC power is the key to ensuring efficient and stable operation of the system.

[0084] In this embodiment, the controller may be a microcontroller (MCU). It is understood that the microcontroller is an embedded controller having functions such as an integrated ADC, PWM output, and a communication interface (e.g., I²C, SPI, and UART), and is capable of performing the above-mentioned operations of calculating the DC power of the DC bus based on the voltage and current signals, and adjusting the resistance value of the variable resistor based on the change of the DC power, so that when the DC power reaches a maximum value, the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0085] In this embodiment, the controller may be a digital signal processor (DSP), which can sample voltage and current signals at high speed and perform fast power calculation and regulation control.

[0086] In this embodiment, the controller may be a field programmable gate array (FPGA). It is understood that a field programmable gate array is a hardware programmable logic device capable of parallel processing. A field programmable gate array can perform ultra-high-speed data acquisition, power calculation and control operations.

[0087] In this embodiment, the controller may also be an application specific integrated circuit (ASIC).

[0088] In this embodiment, the controller may also be an embedded system. For example, the embedded system may be an embedded system based on a Linux operating system. The embedded system based on a Linux operating system may perform the above-mentioned operation of calculating the DC power of the DC bus based on the voltage and current signals, and adjusting the resistance value of the variable resistor based on the change of the DC power, so that when the DC power reaches a maximum value, the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0089] This embodiment achieves effective absorption and suppression of ripple current in the DC bus by introducing an adjustable variable resistor, an absorption capacitor, and a DC ripple suppression circuit equipped with a current sampling device and a voltage sampling device. In this process, the controller dynamically calculates the DC power based on the voltage and current signals collected in real time, and optimizes the power output by adjusting the resistance value of the variable resistor. When the DC power reaches the maximum value, the total loss of the entire system is minimized, thereby effectively solving the technical problem of large loss when suppressing DC ripples in the prior art and improving the overall efficiency and stability of the system. Specifically, this embodiment can achieve the best ripple absorption effect under different working conditions and effectively reduce energy waste by flexibly adjusting the resistance value of the variable resistor. The real-time acquisition of current and voltage signals provides accurate data support for the controller, so that the DC ripple suppression circuit can adjust the resistance value of the variable resistor based on the change trend of the DC power, ensure operation at the maximum power point, and reduce overall losses. When the DC power reaches the maximum, the overall loss is minimized, successfully solving the problem of high loss in the prior art, and improving the efficiency and stability of the entire DC ripple suppression circuit.

[0090] In some cases, in some technical solutions, the DC ripple suppression circuit is continuously connected to the DC bus and cannot be flexibly adjusted according to the real-time situation. This method remains connected when the DC bus voltage fluctuates slightly or the ripple current is not significant, resulting in unnecessary energy loss. The variable resistor and absorption capacitor in the DC ripple suppression circuit will still cause power loss when there is no ripple current to absorb, affecting the overall energy efficiency. When the DC ripple suppression circuit is always connected, heat is generated when the current passes through the resistor, which increases the total power loss in both static and dynamic conditions. This power loss is particularly significant under high ripple or low load conditions, resulting in reduced system energy efficiency and even overheating damage to the equipment. Moreover, due to the fluctuations in current and voltage, the continuously connected ripple suppression circuit may cause the equipment to operate under non-optimal conditions, affecting its performance and stability. For example, loads such as motors or inverters may suffer from reduced operating efficiency, increased failure rates and maintenance costs when faced with unstable power supplies.

[0091] In response to the above problems, such as Figure 2 As shown, in some embodiments, the DC ripple suppression circuit further includes: A switch device, one end of which is connected to the positive bus of the DC bus, and the other end is connected to one end of the variable resistor, and the control end of the switch device is connected to the controller, and is used to selectively connect or disconnect the DC ripple suppression circuit to or from the DC bus based on an instruction issued by the controller.

[0092] In this embodiment, the switch device may be a relay. It is understood that a relay is an electrical control device that uses electromagnetic principles to achieve automatic control of a switch. A relay may be composed of a coil, a contact, a spring, and other parts. When the coil is energized, the generated magnetic field will attract the contact to achieve the connection or disconnection of the circuit. When the controller sends a signal, the coil of the relay is energized, the contact is closed, and the DC ripple suppression circuit is connected to the DC bus; when the control signal is disconnected, the contact is disconnected, and the DC ripple suppression circuit is disconnected from the DC bus.

[0093] In this embodiment, the switch device may be a MOSFET. It is understood that when the controller applies a control signal to the gate of the MOSFET, the MOSFET is turned on and current can flow from the source to the drain. When the gate signal disappears or drops below a threshold, the MOSFET is turned off and the current is cut off.

[0094] In this embodiment, the switch device may also be an IGBT. When the controller applies voltage to the gate of the IGBT, the IGBT is turned on, allowing current to flow; when the gate voltage drops below a certain value, the IGBT turns off the current flow.

[0095] In this embodiment, the switch device may also be a solid-state relay.

[0096] In this embodiment, the switch device may also be an electronic switch.

[0097] In this embodiment, by introducing a switching device, selective access or disconnection of the DC ripple suppression circuit is achieved. This flexible control capability enables the DC power system to adjust the ripple current absorption effect according to actual needs, thereby improving energy transmission efficiency, stability and flexibility. By selectively accessing the DC ripple suppression circuit, the fluctuation of ripple current and voltage can be effectively suppressed, making the DC voltage more stable, and improving the stability and reliability of the DC power system. By selectively disconnecting the DC ripple suppression circuit, the ineffective power loss can be reduced and the energy utilization efficiency can be improved. This setting can make the DC power system operate more efficiently, extend the service life of the equipment, and adapt to different working conditions and load changes.

[0098] In some cases, the absorption capacitor in the DC ripple suppression circuit may remain charged for a long time after being charged, which may cause the absorption capacitor to be unable to provide support for subsequent ripple absorption in a timely manner, thereby affecting the overall performance and response speed of the DC ripple suppression circuit.

[0099] In response to the above problems, such as Figure 3 As shown, in some embodiments, the DC ripple suppression circuit further includes: A discharge resistor is connected in parallel with the absorption capacitor and is used to provide a discharge path for the absorption capacitor after the absorption capacitor is fully charged, so that the absorption capacitor can be discharged in time during the subsequent ripple absorption process.

[0100] In this embodiment, the design of setting a discharge resistor in parallel with the absorption capacitor can effectively improve the performance and reliability of the DC ripple suppression circuit. After the absorption capacitor is charged, the discharge resistor provides an effective discharge path, so that the absorption capacitor can quickly release the stored electrical energy, ensuring that it can be discharged in time during the subsequent ripple absorption process. This design not only improves the response speed of the absorption capacitor to frequent ripples and enhances the dynamic performance of the DC ripple suppression circuit, but also prevents the risk of overcharging caused by the absorption capacitor remaining charged for a long time, reduces the probability of failure, and thus enhances the stability and safety of the entire system.

[0101] In some cases, the voltage sampling technology in the related art may not be able to accurately and in real time reflect the voltage state of the DC bus, resulting in untimely response to power fluctuations, thereby affecting the stability and efficiency of the overall system. In addition, the voltage sampling device in the related art may have problems such as signal attenuation and noise interference when collecting positive and negative voltage signals, especially in a high-frequency ripple environment, where the sampling accuracy is significantly reduced.

[0102] Therefore, in some embodiments, Figure 4 As shown, the voltage sampling device may include: A first voltage sampling device has one end connected to the positive bus of the DC bus and is used to collect a positive voltage signal of the DC bus.

[0103] In this embodiment, one end of the first voltage sampling device is connected to the positive bus of the DC bus. The first voltage sampling device can be a voltage divider resistor. The main function of the first voltage sampling device is to monitor the voltage level of the positive electrode of the DC bus in real time. Through the voltage divider resistor, the high voltage signal is reduced to an acceptable range to ensure that it is suitable for subsequent processing and analysis.

[0104] The second voltage sampling device has one end connected to the negative bus of the DC bus and is used to collect the negative voltage signal of the DC bus.

[0105] In this embodiment, one end of the second voltage sampling device is connected to the negative bus of the DC bus. The second voltage sampling device can be a voltage divider resistor. The main function of the second voltage sampling device is to monitor the voltage level of the negative electrode of the DC bus in real time. Through the voltage divider resistor, the high voltage signal is reduced to an acceptable range to ensure that it is suitable for subsequent processing and analysis.

[0106] An operational amplifier circuit, whose input end is respectively connected to the other end of the first voltage sampling device and the second voltage sampling device, and whose output end is connected to the controller, is used to process the received positive voltage signal and negative voltage signal and then input them into the controller.

[0107] In this embodiment, the input end of the operational amplifier circuit is connected to the output end of the first voltage sampling device and the output end of the second voltage sampling device respectively. The input end of the operational amplifier receives signals from the two sampling devices to realize the processing of the positive and negative voltages. The operational amplifier circuit is used to amplify and process the voltage signals of the positive and negative electrodes. After amplification, the signal will be transmitted to the controller for further calculation and analysis.

[0108] In this technical solution, by introducing the first voltage sampling device and the second voltage sampling device, and combining the operational amplifier circuit, the acquisition accuracy and stability of the voltage signal can be effectively improved. The operational amplifier can amplify and process the voltage signals of the positive and negative electrodes, ensuring that the voltage signals received by the controller are accurate and clear, thereby achieving more effective ripple suppression and power management, significantly improving the response capability to voltage fluctuations, and solving the deficiencies in related technologies.

[0109] In some cases, the voltage sampling and signal processing technology in the related art may not be able to effectively filter out the high-frequency noise and interference in the DC bus voltage signal, which will cause the controller to receive unstable or inaccurate voltage signals, thereby affecting the performance and responsiveness of the entire system. The presence of high-frequency noise will not only reduce the accuracy of the measurement, but may also interfere with subsequent signal processing and power regulation, thereby affecting the suppression effect of DC ripple.

[0110] Therefore, in some embodiments, the operational amplifier circuit comprises: A filter inductor, one end of which is respectively connected to the other end of the first voltage sampling device and the other end of the second voltage sampling device, is used to suppress high-frequency noise in the positive voltage signal and the negative voltage signal.

[0111] In this embodiment, the function of the filter inductor is to suppress the high-frequency noise in the positive and negative voltage signals passing through the first voltage sampling device and the second voltage sampling device. When the high-frequency noise signal flows through the filter inductor, the filter inductor will generate impedance to the high-frequency signal, thereby reducing the amplitude of the noise signal and ensuring that the output voltage signal is smoother and more stable.

[0112] The operational amplifier has an input end connected to the other end of the filter inductor and is used to process the positive voltage signal and the negative voltage signal.

[0113] In this embodiment, the operational amplifier can receive the positive and negative voltage signals processed by the filter inductor and further amplify and process these signals. The operational amplifier can increase the strength of the signal to make it suitable for subsequent controller analysis and calculation.

[0114] The LC filter network is connected in parallel with the operational amplifier and is used to perform filtering processing on the positive voltage signal and the negative voltage signal.

[0115] In this embodiment, the LC filter network is connected in parallel with the operational amplifier to perform further filtering on the positive voltage signal and the negative voltage signal, in order to further reduce the high-frequency noise and voltage fluctuation in the signal and improve the stability of the signal.

[0116] This embodiment effectively improves the processing performance of the DC bus voltage signal through the design of the operational amplifier circuit, combined with the filter inductor, operational amplifier, and LC filter network. The filter inductor can suppress the high-frequency noise in the positive and negative voltage signals, and improve the clarity and stability of the signal; the operational amplifier is used to amplify the processed voltage signal to ensure that the controller receives a signal of appropriate strength and accuracy; the LC filter network further smoothes the output signal, reduces fluctuations, and improves the anti-interference ability of the system. In summary, this embodiment significantly improves the response speed and overall performance to voltage fluctuations, ensuring the reliable operation of the DC ripple suppression circuit in a dynamic environment.

[0117] like Figure 8 and Fig. 9 In a specific embodiment, a DC ripple suppression circuit is provided. The DC ripple suppression circuit may include: The relay K1 has one end connected to the positive bus of the DC bus and is used to control the DC ripple suppression circuit to be connected to the DC bus or disconnected from the DC ripple suppression circuit. The control end of the relay K1 can be connected to the controller.

[0118] The variable resistor Rn has one end connected to the positive bus of the DC bus through the relay K1, and is used to adjust the magnitude of the current in the DC ripple suppression circuit.

[0119] An absorption capacitor C1 has one end connected to the other end of the variable resistor Rn, and the other end of the absorption capacitor C1 is connected to the negative bus of the DC bus for absorbing DC ripple.

[0120] The voltage sampling device comprises a sampling resistor R1 and a sampling resistor R2.

[0121] Specifically, the sampling resistor R1 is connected between the positive pole DC+ of the DC bus and the voltage sampling point V_DC+. The sampling resistor R1 is used as a sampling resistor for the positive pole to collect the voltage signal of the positive pole of the DC bus. The sampling resistor R1 ensures that the V_DC+ voltage signal is proportional to the DC bus voltage and can accurately reflect the voltage condition of the positive pole of the bus. The sampling resistor R2 is connected between the negative pole DC- of the DC bus and the voltage sampling point V_DC-. The sampling resistor R2 is used as a sampling resistor for the negative pole to collect the voltage signal of the negative pole of the DC bus.

[0122] The voltage sampling device also includes: an operational amplifier circuit. The operational amplifier circuit includes: The filter inductor L1 includes two filter inductors. One end of one filter inductor L1 is connected to the voltage sampling point V_DC+. One end of the other filter inductor L1 is connected to the voltage sampling point V_DC-. The two filter inductors L1 are used to suppress high-frequency noise in the positive voltage signal and the negative voltage signal.

[0123] The operational amplifier U1 has an input end connected to the other end of the filter inductor L1 and is used to process the positive voltage signal and the negative voltage signal.

[0124] The LC filter network is connected in parallel with the operational amplifier U1 to filter the positive voltage signal and the negative voltage signal. The operational amplifier is the core component of the circuit. Its input terminal receives signals from V_DC+ and V_DC-, and its output terminal provides an amplified signal (AD) to the controller.

[0125] The LC filter network includes: The filter capacitor C2 is used to filter high-frequency noise and provide a bypass path so that the high-frequency signal can be bypassed through the capacitor.

[0126] The filter inductor L2, working together with the filter capacitor C2, further suppresses high frequency signals, allowing the amplifier to process cleaner voltage signals.

[0127] The current sampling device A1 is used to collect the current signal of the DC bus.

[0128] A controller is connected to the relay K1, the variable resistor Rn, the voltage sampling device and the current sampling device A1 respectively. The controller can calculate the DC power of the DC bus based on the voltage and current signals, and adjust the resistance value of the variable resistor based on the change of the DC power, so that when the DC power reaches the maximum value, the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0129] This embodiment provides a control method for a DC ripple suppression circuit, which may include: Collect the electrical signal of the DC bus.

[0130] According to the electrical signal of the DC bus, control is made as to whether the ripple absorption circuit is connected to the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

[0131] The control method of this embodiment collects electrical signals from the DC bus and determines the current state based on these signals, thereby optimizing the output of DC power and achieving effective suppression of DC ripple. This method ensures that when the DC bus is connected, the resistance value of the variable resistor can be dynamically adjusted to maximize the DC power, thereby effectively reducing circuit losses and improving energy efficiency. In addition, by monitoring voltage and current, the control method can respond to changes in a timely manner, ensuring the stability and reliability of the equipment, thereby improving the performance of the DC ripple suppression circuit under various working conditions.

[0132] In some embodiments, the step of controlling whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal includes: Determining whether the ripple absorption circuit needs to be connected to the DC bus; When it is determined that the ripple absorption circuit needs to be connected to the DC bus, the switch device is controlled to close to connect the ripple absorption circuit to the DC bus, so that the ripple absorption circuit absorbs the ripple current in the DC bus.

[0133] This embodiment selectively connects the circuit to the DC bus by judging whether the ripple absorption circuit needs to be connected and controlling the switch device to close when necessary. In this way, the circuit can be connected when ripple suppression is required and disconnected when there is no ripple, which significantly reduces the energy loss of the system and prolongs the life of the components.

[0134] In some implementations, the step of determining whether the ripple absorption circuit needs to be connected to the DC bus includes: Determining whether the fluctuation amplitude of the voltage signal satisfies a preset first voltage fluctuation amplitude threshold, and / or determining whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold; When a preset first voltage fluctuation amplitude threshold and / or a preset first current fluctuation amplitude threshold are met, it is determined that the DC ripple suppression circuit needs to be connected to the DC bus.

[0135] This embodiment determines whether to perform the next step by judging whether the fluctuation amplitude of voltage and / or current exceeds a preset threshold value and taking this as a judgment standard. This method can accurately identify the actual fluctuation situation in the system, thereby avoiding unnecessary energy consumption and optimizing the overall efficiency of the system.

[0136] In some embodiments, the control method further comprises: When the DC power reaches a maximum value, the resistance value of the current ripple absorption circuit is reduced based on the resistance value of the current ripple absorption circuit, thereby improving the absorption capacity of the ripple absorption circuit for the ripple current in the DC bus; Determine whether the fluctuation amplitude of the voltage signal satisfies a preset second voltage fluctuation amplitude threshold, and / or determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset second current fluctuation amplitude threshold; wherein the second voltage fluctuation amplitude threshold is smaller than the first voltage fluctuation amplitude threshold, and the second current fluctuation amplitude threshold is smaller than the first current fluctuation amplitude threshold; When a preset second voltage fluctuation amplitude threshold and / or a preset second current fluctuation amplitude threshold are met, the reduction of the resistance value of the ripple absorption circuit is stopped.

[0137] In this implementation, on the basis of the DC power reaching the maximum value, by further reducing the resistance value of the variable resistor in the ripple absorption circuit, the ripple absorption circuit's ability to absorb the ripple current in the DC bus is improved, meeting the need for higher-precision ripple suppression. By setting the second voltage fluctuation amplitude threshold and the second current fluctuation amplitude threshold (both smaller than the first threshold), this implementation can more strictly monitor the voltage and current fluctuations in the system to ensure that the ripple is more thoroughly suppressed while meeting high-precision requirements. This not only improves the stability and reliability of the system, but also optimizes the overall performance and reduces the impact of residual fluctuations on the equipment in certain application scenarios that have higher requirements for voltage and current fluctuations.

[0138] This embodiment provides a control method for a DC ripple suppression circuit, wherein the DC ripple suppression circuit can be selectively connected to a DC bus, and the DC bus is used to supply power to a main circuit.

[0139] The method may be executed by a controller, such as Figure 5 As shown, the method may include: Step S104: When the DC ripple suppression circuit is connected to the DC bus, a voltage signal and a current signal of the current DC bus are collected.

[0140] In this embodiment, the acquisition action can be represented as a process of real-time monitoring and acquisition of the voltage signal and current signal of the DC bus through the controller. It can be understood that the controller is connected to the voltage sampling device and the current sampling device, and can acquire the voltage signals of the positive and negative poles of the DC bus and the current signal passing through the DC bus through the voltage sampling device and the current sampling device. The acquired analog signal is processed by the ADC preset in the controller and converted into a digital signal.

[0141] In this embodiment, the acquisition action may be a dynamic and continuous operation, and the controller continuously monitors the voltage and current changes of the DC bus during operation so as to reflect the current status in a timely manner.

[0142] Step S106: Based on the voltage signal and / or the current signal, determine whether a preset condition is met.

[0143] In this embodiment, the preset condition may be: the fluctuation amplitude of the current voltage signal needs to meet a first voltage fluctuation amplitude threshold.

[0144] Specifically, the first voltage fluctuation amplitude threshold is represented by the ripple voltage basic problem of the DC power system when the fluctuation amplitude of the voltage signal of the DC power system can meet the first voltage fluctuation amplitude threshold, which can trigger the controller to perform the next step of optimization operation, for example, the controller can be triggered to adjust the variable resistance to the optimal variable resistance value. Thereby, when the DC power reaches the maximum value, the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized. Correspondingly, when the fluctuation amplitude of the voltage signal of the DC power system cannot meet the first voltage fluctuation amplitude threshold, it means that the voltage fluctuation amplitude of the current DC power system is large, and it is necessary to wait for the DC ripple suppression circuit to suppress the voltage fluctuation in the DC bus or increase the resistance value of the variable resistor in the DC ripple suppression circuit so that the DC ripple suppression circuit can further suppress the voltage fluctuation in the DC bus.

[0145] In other words, the first voltage fluctuation amplitude threshold can be expressed as the maximum fluctuation amplitude allowed for the voltage signal of the DC power system under normal working conditions. The first voltage fluctuation amplitude threshold can be pre-set through experiments, simulations or standard specifications, and can be used to evaluate the impact of voltage fluctuations on system performance. When the fluctuation amplitude of the voltage signal of the DC power system meets the threshold, it indicates that the voltage fluctuation is within an acceptable range and the system can operate safely and stably.

[0146] In this embodiment, the preset condition may be that the fluctuation amplitude of the current signal needs to meet the first current fluctuation amplitude threshold. The first current fluctuation amplitude threshold may be expressed as the maximum fluctuation amplitude allowed for the current signal of the DC power system under normal working conditions. Similarly, the first current fluctuation amplitude threshold may also be pre-set through experiments, simulations or standard specifications. When the fluctuation amplitude of the current signal of the DC power system meets the threshold, it indicates that the current fluctuation of the system is within a reasonable range and can ensure the normal operation of the load equipment.

[0147] In this embodiment, the preset condition may also be: the fluctuation amplitude of the current voltage signal needs to meet the first voltage fluctuation amplitude threshold and the fluctuation amplitude of the current current signal needs to meet the first current fluctuation amplitude threshold. In some cases, the preset condition may be that the current voltage signal is required to meet the first voltage fluctuation amplitude threshold and the current current signal is required to meet the first current fluctuation amplitude threshold. The setting of this joint condition is intended to ensure that the DC power system is in a stable state in terms of both voltage and current, and optimize the decision-making basis of circuit control.

[0148] Step S108: When the preset conditions are met, determine the current DC power.

[0149] The determination of the current DC power may be expressed as multiplying the collected voltage signal and current signal to obtain the DC power.

[0150] It is understandable that the determined DC power value will be used for subsequent control decisions. For example, the controller will determine whether to adjust the variable resistor based on the current power value to optimize the working state of the DC ripple suppression circuit. Since the voltage and current in the DC power system fluctuate with the load, the DC power calculated in real time also changes dynamically. The controller continuously monitors the changes in voltage and current to continuously update the power value.

[0151] In a specific embodiment, the controller can extract the current positive and negative voltage signals and calculate the effective voltage value of the DC bus. The effective voltage value can be the difference between the positive voltage and the negative voltage. The current signal obtained by the current sampling device. Substitute the obtained voltage signal and current signal into the DC power calculation formula to obtain the current DC power.

[0152] Step S110: adjusting the resistance value of the variable resistor in the DC ripple suppression circuit so that the DC power reaches a maximum value, thereby minimizing the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit.

[0153] In this embodiment, the adjustment action can be represented by the controller sending an instruction to the variable resistor, and adjusting the resistance value of the variable resistor in the DC ripple suppression circuit through the instruction, for example, increasing the resistance value of the variable resistor or decreasing the resistance value of the variable resistor.

[0154] In this embodiment, the maximum value may be a preset maximum value. The preset maximum value may be a fixed value. The preset maximum value may be obtained by experiment or simulation calculation. For example, multiple experiments may be conducted on the DC power system, and the variable resistor, absorption capacitor and other parameters in the system may be adjusted to find the power peak of the system under different working conditions. After recording these peak powers, these values ​​may be stored in the controller as preset maximum values. The voltage fluctuation and current change of the DC bus may be simulated by performing circuit simulation on the entire circuit. Through the simulation tool, the maximum power output point of the system may be found and stored in the controller as a preset value.

[0155] Specifically, the maximum value may be a maximum value obtained through real-time calculation. The maximum value obtained through real-time calculation is adjusted by the controller according to the collected voltage and current signals through dynamic feedback and optimization algorithm during operation until the DC power is maximized. Therefore, in this case, the maximum value is not fixed, but changes continuously according to the real-time operation of the DC power system. More specifically, the controller can continuously collect the voltage and current of the DC bus through the voltage sampling device and the current sampling device to calculate the current DC power. The controller can change the current size of the absorption circuit by adjusting the resistance value of the variable resistor, thereby affecting the voltage fluctuation of the DC bus. The controller can detect the change of DC power after each adjustment through closed-loop feedback control. If the DC power increases, continue to adjust the variable resistor. If the DC power decreases, adjust the opposite direction until the DC power reaches the peak value.

[0156] In a specific embodiment, step S110 may include: The DC power value determined in step S108 is used as the starting reference point for adjustment. The controller sends an instruction to the variable resistor to start adjusting its resistance value. The initial adjustment can be to slightly increase or decrease the resistance value to observe the impact on the DC power. The controller can control the resistance value of variable resistor devices such as MOSFET, IGBT, or programmable resistor through PWM signals or other control signals. The controller collects the adjusted voltage and current signals again and recalculates the current DC power value. The controller compares the adjusted DC power value with the initial power value before adjustment: if the power increases, it means that the current variable resistor adjustment direction is correct, and the controller will continue to adjust the resistance value in the same direction. If the power decreases, it means that the current adjustment direction is incorrect, and the controller will change the adjustment direction and adjust the resistance value in the opposite direction. After each adjustment of the variable resistor, the controller will collect voltage and current signals in real time and recalculate the DC power value. Through this feedback loop, the controller can determine which resistance value corresponds to the maximum DC power. It can be understood that the process is iterative, and the controller gradually approaches the optimal resistance value by repeatedly adjusting the resistance value, calculating the power, and comparing the power changes. The controller will continue to make iterative adjustments until it finds a point where the DC power will no longer increase, whether the resistance value is increased or decreased. When this happens, it means that the controller has found the maximum value of the DC power, and the variable resistance value at this time is the optimal resistance value. For example, the controller records the DC power values ​​after several consecutive adjustments, and when these power values ​​no longer change significantly, it is considered that the maximum power point has been reached. Or, after a certain adjustment, the power begins to decrease or remain unchanged regardless of further increasing or decreasing the resistance, which means that the power has reached its maximum value at this time. When the DC power reaches its maximum value, it indicates that the system is operating in the optimal state, and the sum of the losses of the DC ripple suppression circuit and the losses of the main circuit is minimized.

[0157] The DC ripple suppression circuit control method of this embodiment collects the voltage and current signals of the DC bus, and judges the current state according to these signals, thereby optimizing the output of DC power, thereby achieving effective suppression of DC ripple. This method ensures that when the DC bus is connected, the resistance value of the variable resistor can be dynamically adjusted to maximize the DC power, thereby effectively reducing the loss of the circuit and improving energy efficiency. In addition, by monitoring the voltage and current, the control method can respond to changes in a timely manner, ensuring the stability and reliability of the equipment, thereby improving the performance of the DC ripple suppression circuit under various working conditions.

[0158] In some cases, if the DC ripple suppression circuit is connected to the DC bus for a long time, regardless of whether the ripple current exists, unnecessary energy loss will be generated, reducing the overall efficiency of the system. In related technologies, the DC ripple suppression circuit is usually always connected to the DC bus, resulting in the circuit still consuming power even when the ripple current is small or non-existent, increasing invalid losses. In addition, continuous access may also cause unnecessary capacitor charging and discharging processes, affecting the service life of circuit components.

[0159] Therefore, in some embodiments, Figure 6 As shown, the control method also includes: Step S100: Determine whether the DC ripple suppression circuit needs to be connected to the DC bus.

[0160] In this embodiment, the controller can calculate the fluctuation amplitude of the voltage signal and the current signal. The calculated voltage fluctuation and current fluctuation amplitude are compared with the preset threshold value: when the fluctuation amplitude of the voltage signal exceeds the set threshold value (for example, it can be the first voltage fluctuation amplitude threshold value), it indicates that there is a large voltage ripple in the system. When the fluctuation amplitude of the current exceeds the set threshold value (for example, it can be the first current fluctuation amplitude threshold value), it indicates that there is a large ripple current in the system.

[0161] If the voltage fluctuation amplitude or the current fluctuation amplitude exceeds the threshold, the controller determines that the DC ripple suppression circuit needs to be connected to the DC bus to suppress the voltage and current fluctuations. If the voltage and current fluctuation amplitudes are both lower than the threshold, the controller determines that the suppression circuit does not need to be connected and keeps the circuit disconnected to avoid unnecessary energy consumption.

[0162] Step S102: When it is determined that the DC ripple suppression circuit needs to be connected to the DC bus, the switch device is controlled to close to connect the DC ripple suppression circuit to the DC bus, so that the DC ripple suppression circuit absorbs the ripple current in the DC bus.

[0163] When it is determined that the DC ripple suppression circuit needs to be connected, the controller sends a signal to trigger the switch device to close, so as to connect the suppression circuit to the DC bus.

[0164] This embodiment introduces steps S100 and S102, and selectively connects the circuit to the DC bus by judging whether the DC ripple suppression circuit needs to be connected and controlling the switch device to close when necessary. In this way, the circuit can be connected when ripple suppression is required and disconnected when there is no ripple, which significantly reduces the energy loss of the system and prolongs the life of the components.

[0165] In some cases, the fluctuations of voltage and current signals in existing DC power systems may be unstable. Especially when DC ripple occurs, the voltage and current fluctuation amplitudes of the system will increase, resulting in reduced equipment operating efficiency and increased power loss. However, in related technologies, many systems are unable to effectively monitor the specific amplitudes of these fluctuations, resulting in an inability to timely determine whether measures need to be taken to suppress the ripple. In particular, when the voltage or current fluctuation amplitude is not precisely controlled, the system may continue to connect to the ripple suppression circuit when it is not necessary, increasing unnecessary power loss.

[0166] Therefore, if Figure 7 As shown, in some embodiments, the step of determining whether a preset condition is met based on the voltage signal and / or the current signal includes: Step S1062: Determine whether the fluctuation amplitude of the voltage signal satisfies a preset first voltage fluctuation amplitude threshold, and / or determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold.

[0167] In this embodiment, it is only necessary to determine whether the fluctuation amplitude of the voltage signal satisfies a preset first voltage fluctuation amplitude threshold.

[0168] In this implementation, it is only necessary to determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold.

[0169] In this embodiment, it is also possible to simultaneously determine whether the fluctuation amplitude of the voltage signal satisfies a preset first voltage fluctuation amplitude threshold and whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold.

[0170] Step S1064: When the preset first voltage fluctuation amplitude threshold and / or the first current fluctuation amplitude threshold are met, it is determined that the preset condition is met.

[0171] This embodiment determines whether the fluctuation amplitude of voltage and / or current exceeds a preset threshold value through steps S1062 and S1064, and uses this as a judgment standard to determine whether to perform the next operation. This method can accurately identify the actual fluctuation situation in the system, thereby avoiding unnecessary energy consumption and optimizing the overall efficiency of the system.

[0172] In some cases, although the DC power can be maximized by adjusting the resistance value of the variable resistor, the ripple suppression effect at this time may not fully meet the requirements of certain high-precision applications. For example, in scenarios with strict requirements on the ripple voltage and current in the DC bus, the system may still have large voltage and current fluctuations.

[0173] Therefore, in some embodiments, the control method further comprises: Step S112: when the DC power reaches the maximum value, the resistance value of the current variable resistor is reduced based on the current resistance value of the variable resistor, thereby improving the absorption capacity of the DC ripple suppression circuit for the ripple current in the DC bus.

[0174] Step S114: determine whether the fluctuation amplitude of the voltage signal satisfies a preset second voltage fluctuation amplitude threshold, and / or determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset second current fluctuation amplitude threshold; wherein, the second voltage fluctuation amplitude threshold is smaller than the first voltage fluctuation amplitude threshold, and the second current fluctuation amplitude threshold is smaller than the first current fluctuation amplitude threshold.

[0175] In this embodiment, the second voltage fluctuation amplitude threshold can be expressed as a threshold value that is less than the first voltage fluctuation amplitude threshold value. This threshold is used to further accurately control the fluctuation of the DC bus voltage to ensure that the voltage fluctuation amplitude is within a lower range. This threshold is used in high-precision scenarios. When the voltage signal fluctuation amplitude of the DC bus is lower than this threshold, it means that the voltage fluctuation in the system is small enough to meet more stringent voltage stability requirements. Compared with the first voltage fluctuation amplitude threshold, the second voltage fluctuation amplitude threshold requires smaller voltage fluctuations to ensure higher voltage stability and system reliability. When the voltage fluctuation amplitude does not meet this threshold, the controller will continue to adjust the variable resistance to enhance the suppression effect until the fluctuation amplitude drops below the threshold.

[0176] In this embodiment, the second current fluctuation amplitude threshold can be expressed as a threshold value that is less than the first current fluctuation amplitude threshold value. This threshold is used to further reduce the current fluctuation amplitude in the DC bus to ensure that the current maintains a smaller fluctuation range under high precision requirements. This threshold is used to ensure that the current fluctuation amplitude is within a smaller range when the current fluctuation in the DC bus must achieve higher precision. When the current signal fluctuation amplitude of the DC bus is less than the second current fluctuation amplitude threshold, it indicates that the current fluctuation in the system meets more precise control requirements and the suppression effect reaches an ideal state. If the current fluctuation does not reach this threshold, the controller will further suppress the fluctuation by continuing to adjust the variable resistor until the higher precision standard is met.

[0177] Step S116: When the preset second voltage fluctuation amplitude threshold and / or the second current fluctuation amplitude threshold are met, stop reducing the resistance value of the variable resistor.

[0178] In this implementation, on the basis of the DC power reaching the maximum value, by further reducing the resistance value of the variable resistor, the DC ripple suppression circuit is able to absorb the ripple current in the DC bus, meeting the demand for higher precision ripple suppression. By setting the second voltage fluctuation amplitude threshold and the second current fluctuation amplitude threshold (both smaller than the first threshold), this implementation can more strictly monitor the voltage and current fluctuations in the system to ensure that the ripple is more thoroughly suppressed while meeting high precision requirements. This not only improves the stability and reliability of the system, but also optimizes the overall performance and reduces the impact of residual fluctuations on the equipment in certain application scenarios that have higher requirements for voltage and current fluctuations.

[0179] In some cases, the existing DC ripple suppression circuit cannot efficiently find the optimal operating point of the system. Even if the DC power is controlled by adjusting the resistance value of the variable resistor, the DC power often fails to reach the optimal value due to insensitive power changes or inaccurate adjustment steps. This may lead to increased energy consumption, unsatisfactory suppression effects, and even failure to minimize losses. The related art lacks an efficient dynamic adjustment method that can quickly and accurately find the maximum value of the DC power and ensure minimal losses during the process of adjusting the variable resistor.

[0180] In some embodiments, the step of adjusting the resistance value of the variable resistor in the DC ripple suppression circuit so that the DC power reaches a maximum value, thereby minimizing the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit, includes: Step S1102: continuously increasing or decreasing the resistance value of the variable resistor in the DC ripple suppression circuit so that the DC power changes continuously.

[0181] Step S1104: When the DC power does not change regardless of whether the resistance value of the variable resistor in the DC ripple suppression circuit is increased or decreased, the DC power at this time is taken as the maximum value, and the resistance value of the variable resistor in the DC ripple suppression circuit is stopped from being adjusted.

[0182] In this embodiment, by continuously adjusting the resistance value of the variable resistor in the DC ripple suppression circuit, the controller can monitor the change of DC power in real time and accurately find the maximum value of DC power. When the power no longer changes with the resistance value, the adjustment is stopped to ensure that the system operates at the optimal power point. This process can effectively reduce unnecessary energy loss, so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized. At the same time, the problem of insufficient optimization of DC power due to improper adjustment in the related art is avoided, and the overall efficiency and reliability are improved.

[0183] In some cases, the DC ripple suppression circuit is prone to fall into the trap of local optimal values ​​when adjusting the variable resistor, resulting in the DC power failing to reach the global optimal value. This local optimal situation is usually caused by an inflexible adjustment strategy or an imperfect algorithm, which causes the system to misjudge the power peak, ultimately resulting in the circuit's energy efficiency not being maximized and the loss not being minimized. The related technology lacks an optimization algorithm that can effectively avoid the local optimal problem to ensure the global optimal performance of the system.

[0184] In some embodiments, the step of adjusting the resistance value of the variable resistor in the DC ripple suppression circuit so that the DC power reaches a maximum value, thereby minimizing the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit, includes: Based on a preset optimization algorithm, the resistance value of the variable resistor in the DC ripple suppression circuit is continuously adjusted so that the DC power changes continuously; wherein the preset optimization algorithm is used in the process of adjusting the resistance value of the variable resistor to avoid the local optimal value of the maximum value of the DC power and to find the global optimal value of the maximum value of the DC power.

[0185] In this embodiment, the preset optimization algorithm may be a gradient descent algorithm. Specifically, the controller calculates the gradient of the current DC power relative to the resistance value. According to the direction of the gradient, the controller may adjust the resistance value of the variable resistor to change in the direction of increasing DC power. When the gradient approaches zero (i.e., the power no longer changes), the adjustment is stopped, and it is considered that the global optimal power value has been found.

[0186] In this embodiment, the preset optimization algorithm may be a particle swarm optimization algorithm. Specifically, during initialization, multiple particles are initialized, each particle representing a resistance value. The DC power corresponding to each particle is calculated, and its historical optimal power value is recorded. All particles adjust the resistance value according to the individual and group optimal positions, and perform the next round of calculations. This process is repeated until all particles converge to the global optimal power point.

[0187] In this embodiment, the preset optimization algorithm can be a simulated annealing algorithm. Specifically, the controller starts with an initial resistance value and calculates the current DC power. Each time, a new resistance value is randomly selected and the new DC power is calculated. If the new DC power is larger, the resistance value is accepted; if the power becomes smaller, whether to accept the value is determined based on probability. As the number of iterations increases, the random disturbance decreases and gradually converges to the global optimal power.

[0188] When the value of the DC power reaches a global optimal value, the adjustment of the resistance value of the variable resistor in the DC ripple suppression circuit is stopped.

[0189] In this embodiment, by introducing a preset optimization algorithm, it is possible to effectively avoid the DC power from falling into the dilemma of a local optimal value during the adjustment process. The preset optimization algorithm enables the resistance value of the variable resistor to be continuously and dynamically adjusted, ensuring that the controller can fully search for the global maximum value of the DC power. When the global optimal power point is reached, the controller stops adjusting to ensure that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized. This approach improves the overall energy efficiency of the system, ensures accurate power optimization, and reduces unnecessary energy consumption, thereby enhancing the reliability and stability of the system.

[0190] In some embodiments, the control method further comprises: When the preset condition is not met, the resistance value of the variable resistor in the DC ripple suppression circuit is reduced.

[0191] In this embodiment, when the preset conditions are not met, by reducing the resistance value of the variable resistor, the current flow in the DC ripple suppression circuit can be increased, thereby enhancing its ability to absorb ripple current. Reducing the resistance value can more quickly and effectively suppress voltage or current fluctuations in the DC bus, especially in the case of large fluctuations or strong ripples, which helps to improve the stability and performance of the DC power system. This ensures that the system can make timely adjustments when the fluctuation exceeds the preset range, so that the ripple current is better controlled, the overall efficiency of the system is improved, and smooth operation is guaranteed.

[0192] According to an embodiment of the present invention, an electronic device is provided. Fig.10 The electronic device in this embodiment may include one or more of the following components: a processor, a network interface, a memory, a non-volatile memory, and one or more applications, wherein the one or more applications may be stored in the non-volatile memory and configured to be executed by one or more processors, and the one or more programs are configured to execute the method described in the aforementioned method embodiment.

[0193] According to an embodiment of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a computer, the computer executes the method described in any of the above embodiments.

[0194] According to an embodiment of the present invention, a computer program product including instructions is also provided. When the instructions are executed by a computer, the computer executes the method in any one of the above embodiments.

[0195] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0196] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, and this embodiment will not be described in detail here.

[0197] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0198] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0199] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A DC ripple suppression circuit, connected between a DC bus and a main circuit, characterized in that: include: A ripple absorption circuit can be selectively connected to the positive bus and the negative bus of the DC bus; An electrical signal acquisition circuit, electrically connected to the DC bus, for acquiring an electrical signal from the DC bus; The controller is connected to the electrical signal acquisition circuit and the ripple absorption circuit respectively, and is used to control whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

2. The circuit according to claim 1, characterized in that The ripple absorption circuit comprises: A variable resistor, one end of which is connected to the positive bus of the DC bus, and is used to adjust the magnitude of the current in the DC ripple suppression circuit; An absorption capacitor, one end of which is connected to the other end of the variable resistor, and the other end of the absorption capacitor is connected to the negative bus of the DC bus, for absorbing DC ripple.

3. The circuit according to claim 2, characterized in that The ripple absorption circuit comprises: A switch device, one end of which is connected to the positive bus of the DC bus, and the other end is connected to one end of the variable resistor, and the control end of the switch device is connected to the controller, and is used to selectively connect or disconnect the ripple absorption circuit to or from the DC bus based on an instruction issued by the controller.

4. The circuit according to claim 2, characterized in that The ripple absorption circuit comprises: A discharge resistor is connected in parallel with the absorption capacitor and is used to provide a discharge path for the absorption capacitor after the absorption capacitor is fully charged, so that the absorption capacitor can be discharged in time during the subsequent ripple absorption process.

5. The circuit according to claim 1, characterized in that The electrical signal acquisition circuit comprises: a voltage sampling device and a current sampling device, which are used to collect voltage and current signals of the DC bus respectively.

6. The circuit according to claim 5, characterized in that The voltage sampling device comprises: A first voltage sampling device, one end of which is connected to the positive bus of the DC bus and is used to collect the positive voltage signal of the DC bus; A second voltage sampling device, one end of which is connected to the negative bus of the DC bus and is used to collect a negative voltage signal of the DC bus; An operational amplifier circuit, whose input end is respectively connected to the other end of the first voltage sampling device and the second voltage sampling device, and whose output end is connected to the controller, is used to process the received positive voltage signal and negative voltage signal and then input them into the controller.

7. The circuit according to claim 6, characterized in that The operational amplifier circuit comprises: A filter inductor, one end of which is connected to the other end of the first voltage sampling device and the second voltage sampling device respectively, and is used to suppress high-frequency noise in the positive voltage signal and the negative voltage signal; An operational amplifier, whose input end is connected to the other end of the filter inductor, and is used to process the positive voltage signal and the negative voltage signal; The LC filter network is connected in parallel with the operational amplifier and is used to perform filtering processing on the positive voltage signal and the negative voltage signal.

8. A control method for a DC ripple suppression circuit, characterized in that: include: Collect the electrical signal of DC bus; According to the electrical signal of the DC bus, control is made to determine whether the ripple absorption circuit is connected to the DC bus to absorb the ripple in the electrical signal and keep the DC power of the main circuit at a maximum value so that the sum of the loss of the DC ripple suppression circuit and the loss of the main circuit is minimized.

9. The control method according to claim 8, characterized in that: The step of controlling whether the ripple absorption circuit is connected to the DC bus according to the electrical signal of the DC bus to absorb the ripple in the electrical signal comprises: Determining whether the ripple absorption circuit needs to be connected to the DC bus; When it is determined that the ripple absorption circuit needs to be connected to the DC bus, the switch device is controlled to close to connect the ripple absorption circuit to the DC bus, so that the ripple absorption circuit absorbs the ripple current in the DC bus.

10. The control method according to claim 9, characterized in that: The step of determining whether the ripple absorption circuit needs to be connected to the DC bus includes: Determining whether the fluctuation amplitude of the voltage signal of the DC bus satisfies a preset first voltage fluctuation amplitude threshold, and / or determining whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset first current fluctuation amplitude threshold; When a preset first voltage fluctuation amplitude threshold and / or a preset first current fluctuation amplitude threshold are met, it is determined that the ripple absorption circuit needs to be connected to the DC bus.

11. The control method according to claim 10, characterized in that: The control method further comprises: When the DC power reaches a maximum value, the resistance value of the current ripple absorption circuit is reduced based on the resistance value of the current ripple absorption circuit, thereby improving the absorption capacity of the ripple absorption circuit for the ripple current in the DC bus; Determine whether the fluctuation amplitude of the voltage signal satisfies a preset second voltage fluctuation amplitude threshold, and / or determine whether the fluctuation amplitude of the current signal of the DC bus satisfies a preset second current fluctuation amplitude threshold; wherein the second voltage fluctuation amplitude threshold is smaller than the first voltage fluctuation amplitude threshold, and the second current fluctuation amplitude threshold is smaller than the first current fluctuation amplitude threshold; When a preset second voltage fluctuation amplitude threshold and / or a preset second current fluctuation amplitude threshold are met, the reduction of the resistance value of the ripple absorption circuit is stopped.

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