Electric power filtering circuit and electric power filtering method for reducing electric energy loss

Abstract

The invention discloses an electric power filtering circuit and an electric power filtering method for reducing electric energy loss, electric power enters the whole filtering circuit system through an electric power input module, and in the filtering processing process of the system, an EMI filter firstly suppresses electromagnetic interference from a power grid. Through the EMI filter, the performance of the whole power filter circuit is improved, and it is ensured that power equipment can operate in a more stable and safer environment. The electric power filtered by the EMI enters a rectifier, and the rectifier converts alternating current into direct current and inputs the direct current into a filtering control module for filtering control. Wherein the filtering control is the core module of the system, the filtering control module is used for carrying out accurate filtering and self-adaptive adjustment on direct current, harmonic waves and ripple waves are effectively filtered out, the electric energy quality and the utilization efficiency are improved, and safe and stable operation of an electric power system is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of power filtering, and in particular to a power filtering circuit and a power filtering method for reducing power loss. Background Art

[0002] In modern power systems, the quality and efficiency of electric energy are key indicators for measuring the performance of the entire system. With the rapid development of science and technology, nonlinear loads such as power electronic equipment and variable frequency speed control devices have been widely used in power systems. However, the introduction of these nonlinear loads has led to the appearance of a large number of harmonics and ripple components in the power system.

[0003] The presence of harmonics and ripples has a serious impact on the stable operation and power quality of the power system. They will distort the waveform of the grid voltage and current, reduce the purity of the electric energy, and thus affect the normal operation and life of the power equipment. More seriously, harmonics and ripples will also increase the reactive power loss in the grid, resulting in a significant decrease in the operating efficiency of the grid equipment. In extreme cases, these adverse factors may even cause equipment failure or damage, posing a threat to the safe and stable operation of the entire power system.

[0004] In order to deal with the problems caused by harmonics and ripples, existing power filter circuits mainly rely on passive filter components, such as inductors, capacitors and other components to filter out these undesirable components. Passive filter circuits have been widely used due to their simple structure and relatively low cost. However, in practical applications, passive filter circuits have many shortcomings.

[0005] First, the filtering effect of the passive filter circuit is not ideal. Since the frequency and amplitude of harmonics and ripples often change with the changes in load and grid parameters, it is difficult for the passive filter circuit to accurately filter these undesirable components. Secondly, the passive filter circuit is very sensitive to changes in grid parameters. When the grid parameters change, the filtering effect of the passive filter circuit will be greatly reduced, and even resonance may occur, further deteriorating the power quality. Finally, when the load changes greatly, the filtering performance of the passive filter circuit will also be seriously affected, and it is difficult to meet the high requirements of modern power systems for power quality.

[0006] In summary, the existing passive filter circuits have many deficiencies in dealing with harmonic and ripple problems in modern power systems. Therefore, it is necessary to develop a new type of power filtering technology to effectively filter out harmonics and ripples, improve power quality and utilization efficiency, and ensure the safe and stable operation of the power system. Summary of the invention

[0007] Based on the problems raised by the above background technology, the purpose of the present invention is to provide a power filter circuit and a power filter method for reducing power loss, which solves the problems that the existing passive filter circuit has poor filtering effect in practical applications, is sensitive to changes in grid parameters, and is easy to resonate with the grid.

[0008] The present invention is achieved through the following technical solutions:

[0009] A first aspect of the present invention provides a power filter circuit for reducing power loss, comprising:

[0010] A power input module, an EMI filter, a rectifier, a filter control module and a power output module connected in sequence;

[0011] Wherein, the EMI filter is used to suppress electromagnetic interference from the power grid;

[0012] The rectifier is used to convert alternating current into direct current;

[0013] The filtering control module is used for accurately filtering and adaptively adjusting the direct current.

[0014] In the above technical scheme, electric power enters the entire filter circuit system through the power input module. During the system filtering process, the EMI filter first suppresses the electromagnetic interference from the power grid. The EMI filter improves the performance of the entire power filter circuit and ensures that the power equipment can operate in a more stable and safe environment. The electric power after EMI filtering enters the rectifier, which converts the alternating current into direct current, and inputs the direct current into the filter control module for filtering control. Among them, the filtering control is the core module of the present invention. The direct current is accurately filtered and adaptively adjusted through the filtering control module, so as to achieve effective filtering of harmonics and ripples, improve the quality and utilization efficiency of electric energy, and ensure the safe and stable operation of the power system.

[0015] In an optional embodiment, the EMI filter includes:

[0016] Inductor L1, inductor L2, capacitor C1, capacitor C2, capacitor C3 and capacitor C4;

[0017] Among them, the first end of the inductor L1 is connected to the first end of the capacitor C1 and then connected to the first output end of the power input module, the first end of the inductor L2 is connected to the second end of the capacitor C1 and then connected to the second output end of the power input module, the second end of the inductor L1 is respectively connected to the first end of the capacitor C2, the first end of the capacitor C3 and the first input end of the rectifier, the second end of the inductor L2 is respectively connected to the second end of the capacitor C2, the first end of the capacitor C4 and the second input end of the rectifier, and the second end of the capacitor C3 and the second end of the capacitor C4 are grounded.

[0018] In an optional embodiment, the filtering control module includes:

[0019] A main filtering unit, used for filtering the direct current output by the rectifier;

[0020] An input sampling unit, used for performing voltage sampling and amplification processing on the current output by the rectifier;

[0021] An output sampling unit, used for performing voltage sampling and amplification processing on the output of the main filtering unit;

[0022] A main control unit, used to make dynamic adjustments based on the data fed back by the input sampling unit and the output sampling unit, and generate dynamic control instructions;

[0023] A compensation unit is used to compensate the main filtering unit according to the dynamic control instruction of the main control unit.

[0024] In an optional embodiment, the main filtering unit includes:

[0025] Capacitor C5, inductor L3, IGBT tube Q1, diode D1, capacitor C6 and resistor R1;

[0026] Among them, the first end of the capacitor C5 is connected to the first output end of the rectifier, the first input end of the output sampling unit and the first end of the inductor L3; the second end of the capacitor C5 is connected to the second output end of the rectifier, the second input end of the output sampling unit and the emitter of the IGBT tube Q1; the second end of the inductor L3 is connected to the collector of the IGBT tube Q1 and the anode of the diode D1; the gate of the IGBT tube Q1 is connected to the output end of the compensation unit; the anode of the diode D1 is connected to the first end of the capacitor C6, the first end of the resistor R1 and the first input end of the output sampling unit; the emitter of the IGBT tube Q1 is connected to the second end of the capacitor C6, the second end of the resistor R1 and the second input end of the output sampling unit.

[0027] In an optional embodiment, the input sampling unit includes:

[0028] Op amp AR1, diode D2, diode D3, resistor R2 and resistor R3;

[0029] Among them, the inverting input terminal of the operational amplifier AR1 is connected to the cathode of the diode D2, the anode of the diode D3 and the second end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is connected to the anode of the diode D2, the cathode of the diode D3 and the first end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is grounded through the capacitor R2; the output terminal of the operational amplifier AR1 is connected to the first detection input terminal of the main control unit, and the output terminal of the operational amplifier AR1 is connected to the inverting input terminal of the operational amplifier AR1 through the resistor R3.

[0030] In an optional embodiment, the output sampling unit includes:

[0031] Op amp AR2, op amp AR3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8 and capacitor C7;

[0032] The inverting input terminal of the operational amplifier AR2 is connected to the second end of the resistor R1, and the inverting input terminal of the operational amplifier AR2 is grounded through the resistor R5;

[0033] The in-phase input terminal of the operational amplifier AR2 is connected to the first end of the resistor R1 and the output terminal of the operational amplifier AR3, and the in-phase input terminal of the operational amplifier AR2 is grounded through the resistor R4;

[0034] The output end of the operational amplifier AR2 is connected to the first end of the resistor R6 and the first end of the resistor R7, the second end of the resistor R6 is connected to the second detection input end of the main control unit, and the second end of the resistor R7 is connected to the inverting input end of the operational amplifier AR3;

[0035] The non-inverting input terminal of the operational amplifier AR3 is grounded, and the output terminal of the operational amplifier AR3 is connected to the inverting input terminal of the operational amplifier AR3 through the resistor R8 and the capacitor C7 connected in parallel.

[0036] In an optional embodiment, the compensation unit includes:

[0037] Op amp AR4, resistor R9, resistor R10, resistor R11, capacitor C8, capacitor C9 and inductor L4;

[0038] Among them, the in-phase input end of the operational amplifier AR4 is connected to the control output end of the main control unit, the inverting input end of the operational amplifier AR4 is connected to the first end of the resistor R9, the first end of the resistor R10 and the first end of the capacitor C8, and the second end of the resistor R9 is grounded; the second end of the capacitor R10 and the second end of the capacitor C8 are connected to the first end of the capacitor C9, the first end of the inductor L4, the first end of the resistor R11 and the output end of the operational amplifier AR4; the second end of the capacitor C9 is grounded, and the second end of the inductor L4 and the second end of the resistor R11 are connected to the gate of the IGBT tube Q1.

[0039] In an optional embodiment, the main control unit uses an STM32 series microprocessor.

[0040] A second aspect of the present invention provides a power filtering method of a power filtering circuit for reducing power loss, comprising:

[0041] Obtaining power from a power grid through the power input module;

[0042] The EMI filter performs filtering processing on the electric power to suppress electromagnetic interference from the power grid;

[0043] The rectifier converts the filtered power from AC to DC, and inputs the DC to the filter control module;

[0044] The filtering control module performs precise filtering and adaptive adjustment on the direct current;

[0045] The power output module outputs the precisely filtered and adaptively adjusted direct current.

[0046] In an optional embodiment, the filtering control module performs precise filtering and adaptive adjustment on the direct current, including:

[0047] filtering the direct current output by the rectifier through a main filtering unit;

[0048] Performing voltage sampling and amplification processing on the direct current after filtering by the filtering unit through the output sampling unit, and inputting the amplified direct current into the main control unit;

[0049] The input sampling unit performs voltage sampling and amplification processing on the current output by the rectifier, and inputs the amplified current into the main control unit;

[0050] The main control unit uses a Kalman filter algorithm to calculate the amplified direct current and the amplified current to obtain the harmonic content and the ripple content in the current circuit, and performs compensation calculation on the harmonic content and the ripple content to obtain compensation parameters;

[0051] The compensation parameter is converted into a control signal, and the control signal is sent to a compensation unit, and the compensation unit compensates the main filtering unit using the control signal.

[0052] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0053] The filter control module can accurately filter and adaptively adjust the DC power to effectively filter out harmonics and ripples, improve the quality and efficiency of power, and ensure the safe and stable operation of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0055] Figure 1 A schematic diagram of the structure of a power filter circuit for reducing power loss provided in Embodiment 1 of the present invention;

[0056] Figure 2 A schematic diagram of the structure of an EMI module provided in Embodiment 1 of the present invention;

[0057] Figure 3 A schematic diagram of the principle of the filtering control module provided in Embodiment 1 of the present invention;

[0058] Figure 4 A schematic diagram of the structure of an input sampling unit provided in Embodiment 1 of the present invention;

[0059] Figure 5 A schematic diagram of the structure of an output sampling unit provided in Embodiment 1 of the present invention;

[0060] Figure 6 This is a schematic diagram of the structure of the compensation unit provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0061] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0062] Example 1

[0063] Figure 1 A schematic diagram of a power filter circuit for reducing power loss provided in Embodiment 1 of the present invention is shown in FIG. Figure 1 As shown, a power filter circuit for reducing power loss includes:

[0064] A power input module, an EMI filter, a rectifier, a filter control module and a power output module connected in sequence;

[0065] Wherein, the EMI filter is used to suppress electromagnetic interference from the power grid;

[0066] The rectifier is used to convert alternating current into direct current;

[0067] The filtering control module is used for accurately filtering and adaptively adjusting the direct current.

[0068] It should be noted that electricity enters the entire filter circuit system through the power input module. During the system filtering process, the EMI filter first suppresses the electromagnetic interference from the power grid. The EMI filter improves the performance of the entire power filter circuit and ensures that the power equipment can operate in a more stable and safe environment. The electricity after EMI filtering enters the rectifier, the rectifier converts the alternating current into direct current, and inputs the direct current into the filter control module for filtering control. Among them, the filtering control is the core module of the present invention. The direct current is accurately filtered and adaptively adjusted by the filtering control module to achieve effective filtering of harmonics and ripples, improve the quality and utilization efficiency of electric energy, and ensure the safe and stable operation of the power system.

[0069] In an optional embodiment, the EMI filter includes:

[0070] Inductor L1, inductor L2, capacitor C1, capacitor C2, capacitor C3 and capacitor C4;

[0071] Among them, the first end of the inductor L1 is connected to the first end of the capacitor C1 and then connected to the first output end of the power input module, the first end of the inductor L2 is connected to the second end of the capacitor C1 and then connected to the second output end of the power input module, the second end of the inductor L1 is respectively connected to the first end of the capacitor C2, the first end of the capacitor C3 and the first input end of the rectifier, the second end of the inductor L2 is respectively connected to the second end of the capacitor C2, the first end of the capacitor C4 and the second input end of the rectifier, and the second end of the capacitor C3 and the second end of the capacitor C4 are grounded.

[0072] In this embodiment, the function of the EMI filter is to suppress electromagnetic interference from the power grid, such as Figure 2 As shown, during the operation of the EMI filter, since the inductor has a large impedance to high-frequency signals, the inductors L1 and L2 are mainly used to suppress high-frequency noise. The π-type filter network composed of capacitors C1 and C2 can effectively filter out differential-mode interference, while the T-type filter network composed of capacitors C3 and C4 can effectively filter out common-mode interference.

[0073] Through the combination of inductance and capacitance, the EMI filter can effectively reduce the impact of electromagnetic interference on the circuit and ensure the quality of signal transmission between the power input module and the rectifier. It not only improves the performance of the entire power filter circuit, but also ensures that the power equipment can operate in a more stable and safe environment.

[0074] In an optional embodiment, the filtering control module includes:

[0075] A main filtering unit, used for filtering the direct current output by the rectifier;

[0076] An input sampling unit, used for performing voltage sampling and amplification processing on the current output by the rectifier;

[0077] An output sampling unit, used for performing voltage sampling and amplification processing on the output of the main filtering unit;

[0078] A main control unit, used to make dynamic adjustments based on the data fed back by the input sampling unit and the output sampling unit, and generate dynamic control instructions;

[0079] A compensation unit is used to compensate the main filtering unit according to the dynamic control instruction of the main control unit.

[0080] like Figure 3As shown, the filtering control module includes a main filtering unit, an input sampling unit, an output sampling unit, a main control unit and a compensation unit, wherein the main filtering unit is used to filter the direct current output by the rectifier to suppress harmonics and ripples in the circuit; the input sampling unit is used to perform voltage sampling and amplification processing on the direct current output by the rectifier, and feed it back to the main control unit; the output sampling unit is used to perform voltage sampling and amplification processing on the output of the main filtering unit, and feed it back to the main control unit; the main control unit is used to dynamically adjust the working state of the compensation unit according to the data fed back by the input sampling unit and the output sampling unit; the compensation unit is used to compensate the main filtering unit according to the instructions of the main control unit to reduce energy loss.

[0081] Specifically, the input sampling unit and the output sampling unit monitor the load and the grid conditions respectively, and provide real-time and accurate feedback information to the main control unit. The main control unit dynamically adjusts the working state of the compensation unit based on this information, thereby further optimizing the filtering effect. The compensation unit can adjust its output waveform in real time according to the control signal of the main control unit to generate a compensation waveform opposite to the output waveform of the main filter unit. Compared with the traditional passive filtering circuit, the compensation unit of the present application has higher flexibility and accuracy, and can be adaptively adjusted according to different loads and grid conditions, ensuring the stability and reliability of the filtering effect. The filtering control module realizes accurate filtering and adaptive adjustment of the rectifier output DC power through the combined design of the main filter unit, the input sampling unit, the output sampling unit, the main control unit and the compensation unit.

[0082] In an optional embodiment, the main filtering unit includes:

[0083] Capacitor C5, inductor L3, IGBT tube Q1, diode D1, capacitor C6 and resistor R1;

[0084] Among them, the first end of the capacitor C5 is connected to the first output end of the rectifier, the first input end of the output sampling unit and the first end of the inductor L3; the second end of the capacitor C5 is connected to the second output end of the rectifier, the second input end of the output sampling unit and the emitter of the IGBT tube Q1; the second end of the inductor L3 is connected to the collector of the IGBT tube Q1 and the anode of the diode D1; the gate of the IGBT tube Q1 is connected to the output end of the compensation unit; the anode of the diode D1 is connected to the first end of the capacitor C6, the first end of the resistor R1 and the first input end of the output sampling unit; the emitter of the IGBT tube Q1 is connected to the second end of the capacitor C6, the second end of the resistor R1 and the second input end of the output sampling unit.

[0085] like Figure 3As shown, capacitor C5 plays a role in smoothing and filtering. At the same time, capacitor C5 also serves as the common connection point between the first input terminal and the second input terminal of the output sampling unit, so that the output sampling unit can accurately collect the DC voltage value after filtering. Inductor L3, diode D1, capacitor C6 and resistor R1 together form an active filter circuit for suppressing harmonics and ripples and improving power quality. At the same time, the compensation unit dynamically adjusts the output of the main filter unit through the IGBT tube Q1 to perform adaptive adjustments according to different loads and grid conditions, thereby ensuring the stability and reliability of the filtering effect.

[0086] In an optional embodiment, the input sampling unit includes:

[0087] Op amp AR1, diode D2, diode D3, resistor R2 and resistor R3;

[0088] Among them, the inverting input terminal of the operational amplifier AR1 is connected to the cathode of the diode D2, the anode of the diode D3 and the second end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is connected to the anode of the diode D2, the cathode of the diode D3 and the first end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is grounded through the capacitor R2; the output terminal of the operational amplifier AR1 is connected to the first detection input terminal of the main control unit, and the output terminal of the operational amplifier AR1 is connected to the inverting input terminal of the operational amplifier AR1 through the resistor R3.

[0089] It should be noted that, in the process of the main filter unit performing adaptive adjustment according to different loads and grid conditions, the input sampling unit and the output sampling unit monitor the load and grid conditions respectively. Figure 4 As shown, during the operation of the input sampling unit, the operational amplifier AR1 forms a differential amplifier circuit for sampling and amplifying the voltage across the capacitor C5, and the diodes D2 and D3 between the inverting input terminal and the non-inverting input terminal form a clamping circuit for limiting the voltage range of the input signal to prevent excessive voltage from damaging the operational amplifier AR1, thereby making the detection on the power input side more stable and reliable.

[0090] In an optional embodiment, the output sampling unit includes:

[0091] Op amp AR2, op amp AR3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8 and capacitor C7;

[0092] The inverting input terminal of the operational amplifier AR2 is connected to the second end of the resistor R1, and the inverting input terminal of the operational amplifier AR2 is grounded through the resistor R5;

[0093] The in-phase input terminal of the operational amplifier AR2 is connected to the first end of the resistor R1 and the output terminal of the operational amplifier AR3, and the in-phase input terminal of the operational amplifier AR2 is grounded through the resistor R4;

[0094] The output end of the operational amplifier AR2 is connected to the first end of the resistor R6 and the first end of the resistor R7, the second end of the resistor R6 is connected to the second detection input end of the main control unit, and the second end of the resistor R7 is connected to the inverting input end of the operational amplifier AR3;

[0095] The non-inverting input terminal of the operational amplifier AR3 is grounded, and the output terminal of the operational amplifier AR3 is connected to the inverting input terminal of the operational amplifier AR3 through the resistor R8 and the capacitor C7 connected in parallel.

[0096] It should be noted that, in the process of the main filter unit performing adaptive adjustment according to different loads and grid conditions, the input sampling unit and the output sampling unit monitor the load and grid conditions respectively. Figure 5 As shown, in the output sampling unit, the operational amplifier AR2 is used as a differential amplifier to sample and amplify the output voltage of the main filtering unit. The output end of the operational amplifier AR3 is used to feedback and amplify the output signal of the operational amplifier AR2 through the parallel combination of the resistor R8 and the capacitor C7, and is connected to the non-inverting input end of the operational amplifier AR2 through the feedback loop, forming a negative feedback system, thereby improving the stability and accuracy of the circuit amplification.

[0097] In an optional embodiment, the compensation unit includes:

[0098] Op amp AR4, resistor R9, resistor R10, resistor R11, capacitor C8, capacitor C9 and inductor L4;

[0099] Among them, the in-phase input end of the operational amplifier AR4 is connected to the control output end of the main control unit, the inverting input end of the operational amplifier AR4 is connected to the first end of the resistor R9, the first end of the resistor R10 and the first end of the capacitor C8, and the second end of the resistor R9 is grounded; the second end of the capacitor R10 and the second end of the capacitor C8 are connected to the first end of the capacitor C9, the first end of the inductor L4, the first end of the resistor R11 and the output end of the operational amplifier AR4; the second end of the capacitor C9 is grounded, and the second end of the inductor L4 and the second end of the resistor R11 are connected to the gate of the IGBT tube Q1.

[0100] It should be noted that, in this embodiment, the main control unit calculates the required compensation amount according to the load and grid condition information provided by the input sampling unit and the output sampling unit, and sends the compensation amount in the form of a control signal to the compensation unit, that is, the in-phase input terminal of the operational amplifier AR4 in this embodiment, such as Figure 6 As shown. After receiving this control signal, the op amp AR4 will compare it with the signal at its inverting input terminal. During the comparison process, if the control signal is greater than the signal at the inverting input terminal, the op amp AR4 will output a positive voltage difference, which will be smoothed by the low-pass filter composed of resistor R10 and capacitor C8, and then added to the LC resonant circuit composed of capacitor C9, inductor L4 and resistor R11. The LC resonant circuit will amplify and shape this voltage difference to produce a compensation waveform that is opposite to the output waveform of the main filter unit. In this way, the compensation unit can adjust its working state and output waveform in real time according to changes in load and grid conditions to ensure that the output waveform of the main filter unit always remains in a stable and good state.

[0101] In an optional embodiment, the main control unit uses an STM32 series microprocessor.

[0102] It should be noted that the main control unit in this embodiment acts as the information provided by the input sampling unit and the output sampling unit to adjust the operating parameters of the filter circuit in real time. In this embodiment, the main control unit uses an STM32 series microprocessor, which reads the analog signals of the input sampling unit and the output sampling unit through an internal analog-to-digital converter, and converts these signals into digital signals for processing. Using its built-in algorithm, the main control unit can calculate the current performance state of the filter circuit, and dynamically adjust the parameters of the feedback unit according to the preset optimization target to achieve the best filtering effect. In this process, for example, STM32 can use the Kalman filter algorithm to analyze the input and output data in real time to calculate the harmonics and ripple content in the current circuit.

[0103] The Kalman filter algorithm is an effective recursive filter that can estimate the state of a dynamic system from a series of measurements containing noise. Based on the analysis results of the Kalman filter algorithm, the STM32 microprocessor calculates the compensation parameters that need to be adjusted, including the amplitude and phase of the compensation current. These parameters are calculated based on the preset optimization goals and real-time circuit status, with the aim of further reducing power loss and improving power quality. The calculated compensation parameters are converted into control signals and sent to the compensation unit through the output port of the STM32 microprocessor. These control signals instruct the compensation unit on how to adjust its working state to achieve compensation for the main filter unit.

[0104] A second aspect of the present invention provides a power filtering method of a power filtering circuit for reducing power loss, comprising:

[0105] Obtaining power from a power grid through the power input module;

[0106] The EMI filter performs filtering processing on the electric power to suppress electromagnetic interference from the power grid;

[0107] The rectifier converts the filtered power from AC to DC, and inputs the DC to the filter control module;

[0108] The filtering control module performs precise filtering and adaptive adjustment on the direct current;

[0109] The power output module outputs the precisely filtered and adaptively adjusted direct current.

[0110] In an optional embodiment, the filtering control module performs precise filtering and adaptive adjustment on the direct current, including:

[0111] filtering the direct current output by the rectifier through a main filtering unit;

[0112] Performing voltage sampling and amplification processing on the direct current after filtering by the filtering unit through the output sampling unit, and inputting the amplified direct current into the main control unit;

[0113] The input sampling unit performs voltage sampling and amplification processing on the current output by the rectifier, and inputs the amplified current into the main control unit;

[0114] The main control unit uses a Kalman filter algorithm to calculate the amplified direct current and the amplified current to obtain the harmonic content and the ripple content in the current circuit, and performs compensation calculation on the harmonic content and the ripple content to obtain compensation parameters;

[0115] The compensation parameter is converted into a control signal, and the control signal is sent to a compensation unit, and the compensation unit compensates the main filtering unit using the control signal.

[0116] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A power filter circuit for reducing power loss, characterized in that: include: A power input module, an EMI filter, a rectifier, a filter control module and a power output module connected in sequence; Wherein, the EMI filter is used to suppress electromagnetic interference from the power grid; The rectifier is used to convert alternating current into direct current; The filtering control module is used for accurately filtering and adaptively adjusting the direct current.

2. A power filter circuit for reducing power loss according to claim 1, characterized in that: The EMI filter comprises: Inductor L1, inductor L2, capacitor C1, capacitor C2, capacitor C3 and capacitor C4; Among them, the first end of the inductor L1 is connected to the first end of the capacitor C1 and then connected to the first output end of the power input module, the first end of the inductor L2 is connected to the second end of the capacitor C1 and then connected to the second output end of the power input module, the second end of the inductor L1 is respectively connected to the first end of the capacitor C2, the first end of the capacitor C3 and the first input end of the rectifier, the second end of the inductor L2 is respectively connected to the second end of the capacitor C2, the first end of the capacitor C4 and the second input end of the rectifier, and the second end of the capacitor C3 and the second end of the capacitor C4 are grounded.

3. A power filter circuit for reducing electric energy loss according to claim 1, characterized in that: The filtering control module comprises: A main filtering unit, used for filtering the direct current output by the rectifier; An input sampling unit, used for performing voltage sampling and amplification processing on the current output by the rectifier; An output sampling unit, used for performing voltage sampling and amplification processing on the output of the main filtering unit; A main control unit, used to make dynamic adjustments based on the data fed back by the input sampling unit and the output sampling unit, and generate dynamic control instructions; A compensation unit is used to compensate the main filtering unit according to the dynamic control instruction of the main control unit.

4. A power filter circuit for reducing electric energy loss according to claim 3, characterized in that: The main filtering unit comprises: Capacitor C5, inductor L3, IGBT tube Q1, diode D1, capacitor C6 and resistor R1; Among them, the first end of the capacitor C5 is connected to the first output end of the rectifier, the first input end of the output sampling unit and the first end of the inductor L3; the second end of the capacitor C5 is connected to the second output end of the rectifier, the second input end of the output sampling unit and the emitter of the IGBT tube Q1; the second end of the inductor L3 is connected to the collector of the IGBT tube Q1 and the anode of the diode D1; the gate of the IGBT tube Q1 is connected to the output end of the compensation unit; the anode of the diode D1 is connected to the first end of the capacitor C6, the first end of the resistor R1 and the first input end of the output sampling unit; the emitter of the IGBT tube Q1 is connected to the second end of the capacitor C6, the second end of the resistor R1 and the second input end of the output sampling unit.

5. A power filter circuit for reducing power loss according to claim 4, characterized in that: The input sampling unit comprises: Op amp AR1, diode D2, diode D3, resistor R2 and resistor R3; Among them, the inverting input terminal of the operational amplifier AR1 is connected to the cathode of the diode D2, the anode of the diode D3 and the second end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is connected to the anode of the diode D2, the cathode of the diode D3 and the first end of the capacitor C5; the non-inverting input terminal of the operational amplifier AR1 is grounded through the capacitor R2; the output terminal of the operational amplifier AR1 is connected to the first detection input terminal of the main control unit, and the output terminal of the operational amplifier AR1 is connected to the inverting input terminal of the operational amplifier AR1 through the resistor R3.

6. A power filter circuit for reducing power loss according to claim 4, characterized in that: The output sampling unit comprises: Operational amplifier AR2, operational amplifier AR3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8 and capacitor C7; The inverting input terminal of the operational amplifier AR2 is connected to the second end of the resistor R1, and the inverting input terminal of the operational amplifier AR2 is grounded through the resistor R5; The in-phase input terminal of the operational amplifier AR2 is connected to the first end of the resistor R1 and the output terminal of the operational amplifier AR3, and the in-phase input terminal of the operational amplifier AR2 is grounded through the resistor R4; The output end of the operational amplifier AR2 is connected to the first end of the resistor R6 and the first end of the resistor R7, the second end of the resistor R6 is connected to the second detection input end of the main control unit, and the second end of the resistor R7 is connected to the inverting input end of the operational amplifier AR3; The non-inverting input terminal of the operational amplifier AR3 is grounded, and the output terminal of the operational amplifier AR3 is connected to the inverting input terminal of the operational amplifier AR3 through the resistor R8 and the capacitor C7 connected in parallel.

7. A power filter circuit for reducing power loss according to claim 4, characterized in that: The compensation unit comprises: Op amp AR4, resistor R9, resistor R10, resistor R11, capacitor C8, capacitor C9 and inductor L4; Among them, the in-phase input end of the operational amplifier AR4 is connected to the control output end of the main control unit, the inverting input end of the operational amplifier AR4 is connected to the first end of the resistor R9, the first end of the resistor R10 and the first end of the capacitor C8, and the second end of the resistor R9 is grounded; the second end of the capacitor R10 and the second end of the capacitor C8 are connected to the first end of the capacitor C9, the first end of the inductor L4, the first end of the resistor R11 and the output end of the operational amplifier AR4; the second end of the capacitor C9 is grounded, and the second end of the inductor L4 and the second end of the resistor R11 are connected to the gate of the IGBT tube Q1.

8. A power filter circuit for reducing power loss according to claim 4, characterized in that: The main control unit uses an STM32 series microprocessor.

9. A power filtering method applied to a power filtering circuit for reducing power loss as claimed in any one of claims 1 to 8, characterized in that: include: Obtaining power from a power grid through the power input module; The EMI filter performs filtering processing on the electric power to suppress electromagnetic interference from the power grid; The rectifier converts the filtered power from AC to DC, and inputs the DC to the filter control module; The filtering control module performs precise filtering and adaptive adjustment on the direct current; The power output module outputs the precisely filtered and adaptively adjusted direct current.

10. A power filtering method for reducing power loss according to claim 9, characterized in that: The filtering control module performs precise filtering and adaptive adjustment on the direct current, including: filtering the direct current output by the rectifier through a main filtering unit; Performing voltage sampling and amplification processing on the direct current after filtering by the filtering unit through the output sampling unit, and inputting the amplified direct current into the main control unit; The input sampling unit performs voltage sampling and amplification processing on the current output by the rectifier, and inputs the amplified current into the main control unit; The main control unit uses a Kalman filter algorithm to calculate the amplified direct current and the amplified current to obtain the harmonic content and the ripple content in the current circuit, and performs compensation calculation on the harmonic content and the ripple content to obtain compensation parameters; The compensation parameter is converted into a control signal, and the control signal is sent to a compensation unit, and the compensation unit compensates the main filtering unit by using the control signal.

Images