Harmonic suppression device, method, control unit, electrical appliance, and storage medium

Abstract

The present disclosure provides a harmonic suppression device, method, control unit, power supply device, electrical equipment and storage medium, which relate to the field of motor technology. The device includes: a tuning circuit module connected to the first live wire and the second live wire of the three-phase power supply to perform resonance adjustment processing; a PI-type resonant filter circuit module connected to the tuning circuit module and the third live wire of the three-phase power supply respectively, for performing harmonic filtering processing on the first phase current and the second phase current, as well as the third phase current processed by the tuning circuit module; a rectifier circuit module connected to the PI-type resonant filter circuit module for performing rectification processing and supplying power to the load. The present disclosure can adjust the input voltage, current phase, matching impedance and multiple resonance points in real time to achieve power factor correction of the three-phase power supply, so that the THD of the harmonics of each phase current meets the requirements and the standby power consumption meets the standards; the control is simple, the cost is low and the reliability is high.

Description

Technical Field

[0001] The present disclosure relates to the field of motor technology, and in particular to a harmonic suppression device, method, control unit, power supply device, electrical equipment, and storage medium. Background Art

[0002] European standard EN 61000-3-2 requires that the input current of each phase of three-phase power supply air conditioner equipment should be ≤16A, and each harmonic of each phase input current should meet the requirement of THD <5%. Conventional design uses active power factor correction circuit (APFC circuit) to achieve the 2nd to 40th harmonic requirements. Figure 1 The circuit shown in Figure 1 is a typical existing three-phase APFC circuit. It utilizes an IPM module, a reactor, AC input voltage and current sampling and conditioning circuits, and a DSP control circuit to form a PWM-controlled rectification scheme. This circuit presents complex software design, high technical difficulty, and a high power factor. Furthermore, this three-phase APFC circuit is costly and has poor reliability. Therefore, designing a harmonic suppression circuit with simple control and high reliability is an urgent technical challenge in the industry. Summary of the Invention

[0003] In view of this, a technical problem to be solved by the present invention is to provide a harmonic suppression device, method, control unit, power supply device, electrical equipment and storage medium, which can perform PI-type adjustable resonant filtering processing and rectification processing on each phase current of a three-phase power supply.

[0004] According to a first aspect of the present disclosure, a harmonic suppression device is provided, comprising: a tuning circuit module connected to a first live wire and a second live wire of a three-phase power supply, for performing resonance regulation processing on a first phase current input through the first live wire and a second phase current input through the second live wire; a PI-type resonant filter circuit module connected to the tuning circuit module and the third live wire of the three-phase power supply, respectively, for performing harmonic filtering processing on the first phase current and the second phase current processed by the tuning circuit module, and the third phase current input through the third live wire; a rectifier circuit module connected to the PI-type resonant filter circuit module, for performing rectification processing on the first phase current, the second phase current, and the third phase current processed by the PI-type resonant filter circuit module, to obtain direct current, and output the obtained direct current through a direct current output bus to power a load.

[0005] Optionally, the tuning circuit module includes: a power-on soft start unit, a detection unit and a control unit; the power-on soft start unit is connected to the first live wire and the second live wire; the detection unit collects the voltage signal and the current signal on the DC output bus; the control unit is respectively connected to the power-on soft start unit and the detection unit, and is used to control the power-on soft start unit to perform resonance adjustment processing according to the voltage signal and the current signal.

[0006] Optionally, the power-on soft start unit includes: a first relay, a second relay, a third relay and a resistance-inductance unit; the input end of the first relay is connected to the first live wire, and the output end is connected to the PI-type resonant filter circuit module; the second live wire is connected to the input end of the second relay, and the second live wire is connected to the input end of the third relay through the resistance-inductance unit; the output end of the second relay is connected to the output end of the third relay, and this connection point is connected to the PI-type resonant filter circuit module; the control unit is respectively connected to the control ends of the first relay, the second relay and the third relay, and is used to control the first relay, the second relay and the third relay to be opened or closed.

[0007] Optionally, the detection unit includes: a current sampling circuit and a voltage sampling circuit; the control unit is connected to the current sampling circuit and the voltage sampling circuit respectively; the current sampling circuit is used to collect the current signal on the DC output bus; the voltage sampling circuit is used to collect the voltage signal on the DC output bus.

[0008] Optionally, the PI-type resonant filter circuit module includes: a first inductor, a second inductor, a third inductor, a common-mode inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor and a ninth capacitor; the input end of the first inductor is connected to the third live wire, and the output end is connected to the first input end of the industrial mode inductor through a first connection; the input end of the second inductor is connected to the output end of the first relay, and the output end is connected to the second input end of the industrial mode inductor through a second connection; the input end of the third reactor is connected to the connection point of the output end of the second relay and the output end of the third relay, and the output end is connected to the third input end of the industrial mode inductor through a third connection; the two ends of the first capacitor are respectively connected to the first connection line and the second connection line, and the two ends of the second capacitor are respectively connected to the first connection line and the second connection line. are respectively connected to the first connection line and the third connection line, and both ends of the third capacitor are respectively connected to the second connection line and the third connection line; the first ends of the fourth capacitor, the fifth capacitor and the sixth capacitor are connected, and the second ends of the fourth capacitor, the fifth capacitor and the sixth capacitor are respectively connected to the first connection line, the second connection line and the third connection line; the fourth connection line between the first output end of the industrial mode inductor and the rectifier circuit module is connected to the first end of the seventh capacitor, the fifth connection line between the second output end of the industrial mode inductor and the rectifier circuit module is connected to the first end of the eighth capacitor, and the sixth connection line between the third output end of the industrial mode inductor and the rectifier circuit module is connected to the first end of the ninth capacitor; the second ends of the seventh capacitor, the eighth capacitor and the ninth capacitor are connected, and this connection point is grounded.

[0009] Optionally, the rectifier circuit module includes: a three-phase rectifier bridge and a capacitor component; the three bridge arms of the three-phase rectifier bridge are respectively connected to the fourth line, the fifth line and the sixth line; the first output end of the three-phase rectifier bridge is connected to the positive end of the DC output bus, and the second output end is connected to the negative end of the DC output bus; the capacitor component is connected in parallel to the first output end and the second output end of the three-phase rectifier bridge.

[0010] Optionally, the capacitor assembly includes: a tenth capacitor, an eleventh capacitor, a twelfth capacitor and a thirteenth capacitor; the tenth capacitor and the twelfth capacitor are connected in series to form a first capacitor circuit, and the two ends of the first capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; the eleventh capacitor and the thirteenth capacitor are connected in series to form a second capacitor circuit, and the two ends of the second capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; wherein the connection between the tenth capacitor and the twelfth capacitor is connected to the connection between the eleventh capacitor and the thirteenth capacitor.

[0011] According to a second aspect of the present disclosure, a harmonic suppression method based on the harmonic suppression device as described above is provided, which is executed in a control unit; wherein the load includes a load motor, and the harmonic suppression method includes: calculating the load frequency and the harmonic suppression current based on the voltage signal and the power supply signal on the DC output bus and the parameters of the load motor; and performing harmonic suppression processing based on the load frequency and the harmonic suppression current.

[0012] Optionally, the harmonic suppression current includes: a first axis current; the harmonic suppression processing based on the load frequency and the harmonic suppression current includes: obtaining the operating frequency and the second axis current of the load motor; performing a first comparison processing on the operating frequency and the load frequency, and determining a third axis current based on the result of the first comparison processing; performing a second comparison processing on the result of summing the third axis current and the first axis current and the second axis current, and determining the axis voltage of the load motor based on the result of the second comparison processing.

[0013] Optionally, determining the third axis current based on the result of the first comparison processing includes: calculating the third axis current based on the result of the first comparison processing and using a first PI control algorithm; determining the axis voltage of the load motor based on the result of the second comparison processing includes: calculating the axis voltage of the load motor based on the result of the second comparison processing and using a second PI control algorithm.

[0014] Optionally, the first axis current, the second axis current and the third axis current include: q-axis current; the axis voltage of the load motor includes: q-axis voltage.

[0015] Optionally, the load frequency is calculated as:

[0016]

[0017] The first axis current is calculated as:

[0018]

[0019] Where n is the sampling number, I(n) is the nth sampling current, U(n) is the nth sampling voltage, p is the number of pole pairs of the load motor, k t is the torque coefficient, L d and i d is the d-axis inductance and current, L q and i q is the q-axis inductance and current, and ω is the operating frequency of the load motor.

[0020] Optionally, the first relay, the second relay and the third relay are controlled to be opened or closed for resonance adjustment; wherein, when the operating frequency of the load motor is 0, the first relay, the second relay and the third relay are controlled to be opened.

[0021] According to a third aspect of the present disclosure, a control unit is provided, comprising: a memory; and a processor coupled to the memory, wherein the processor is configured to execute the method described above based on instructions stored in the memory.

[0022] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the instructions are executed by a processor to perform the method described above.

[0023] According to a fifth aspect of the present disclosure, there is provided a power supply device, comprising: the harmonic suppression device as described above.

[0024] According to a sixth aspect of the present disclosure, there is provided an electrical device comprising: the harmonic suppression device as described above.

[0025] Optionally, the electrical equipment includes: a variable frequency air conditioner.

[0026] The harmonic suppression device, method, control unit, power supply device, electrical equipment, and storage medium disclosed herein allow each phase current of a three-phase power supply to pass through a PI-type adjustable resonant point filter circuit, thereby enabling real-time adjustment of input voltage, current phase, matching impedance, and multiple resonant points, thereby achieving power factor correction and reactive power regulation for the three-phase power supply, ensuring that the THD of the harmonics of each phase current meets national standards and that standby power consumption complies with standard requirements. Furthermore, the device features simple control, low cost, and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0028] Figure 1 Schematic diagram of an APFC circuit in the prior art;

[0029] Figure 2 1 is a schematic diagram of a module of an embodiment of a harmonic suppression device according to the present disclosure;

[0030] Figure 3 is a module schematic diagram of another embodiment of a harmonic suppression device according to the present disclosure;

[0031] Figure 4 is a circuit diagram of an embodiment of a harmonic suppression device according to the present disclosure;

[0032] Figure 5 1 is a flow chart of an embodiment of a harmonic suppression method according to the present disclosure;

[0033] Figure 6 Schematic diagram of the control principle of an embodiment of the harmonic suppression method according to the present disclosure;

[0034] Figure 7 Schematic diagram of the effect of using the harmonic suppression method disclosed in the present invention;

[0035] Figure 8 Schematic diagram of a module of an embodiment of a control unit according to the present disclosure. DETAILED DESCRIPTION

[0036] The present disclosure is described more fully below with reference to the accompanying drawings, which illustrate exemplary embodiments of the present disclosure. The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure. The technical solutions of the present disclosure are described in many aspects below in conjunction with various figures and embodiments.

[0037] The terms "first", "second", etc. in the following text are only used to distinguish between the two terms and have no other special meanings.

[0038] In one embodiment, Figure 2 As shown, the present disclosure provides a harmonic suppression device, including a tuning circuit module 10, a PI-type resonant filter circuit module 20, and a rectifier circuit module 30. The tuning circuit module 10 is connected to the first live wire S and the second live wire T of the three-phase power supply 01, and performs resonance regulation processing on the first phase current input through the first live wire S and the second phase current input through the second live wire T.

[0039] The PI-type resonant filter circuit module 20 is connected to the tuning circuit module 10 and the third live wire R of the three-phase power supply 01, respectively, and performs harmonic filtering on the first-phase current and the second-phase current processed by the tuning circuit module 10, as well as the third-phase current input through the third live wire R. The rectifier circuit module 30 is connected to the PI-type resonant filter circuit module 20 and rectifies the first-phase current, the second-phase current, and the third-phase current processed by the PI-type resonant filter circuit module 20 to obtain direct current (DC) and output it through the DC output bus 50 to power a load 40. The load 40 can be of various types, for example, the load 40 can be an inverter unit or a variable frequency motor of a compressor.

[0040] In one embodiment, Figure 3 As shown, the tuning circuit module includes a power-on soft-start unit 11, a detection unit 13, and a control unit 12. The power-on soft-start unit 11 is connected to the first live wire S and the second live wire T. The detection unit 13 collects the voltage and current signals on the DC output bus 50. The control unit 12 is connected to the power-on soft-start unit 11 and the detection unit 13, respectively, and controls the power-on soft-start unit 11 to perform resonance adjustment based on the voltage and current signals.

[0041] In one embodiment, Figure 4 As shown, the power-on soft-start unit 11 includes a first relay S1, a second relay S2, a third relay S3, and a resistance-inductance unit RL. The input of the first relay S1 is connected to the first live wire S, and the output is connected to the PI-type resonant filter circuit module. The second live wire T is connected to the input of the second relay S2, and the second live wire T is connected to the input of the third relay S3 via the resistance-inductance unit RL. The resistance-inductance unit RL can be of various types, having both resistance and inductance characteristics. The output of the second relay S2 is connected to the output of the third relay S3, and this connection point is connected to the PI-type resonant filter circuit module.

[0042] The control unit 12 is connected to the control terminals of the first relay S1, the second relay S2, and the third relay S3, respectively, and is used to control the opening or closing of the first relay S1, the second relay S2, and the third relay S3. The control unit 12 can be implemented in various ways, such as a digital signal processing DSP module, a single-chip microcomputer, etc.

[0043] The detection unit includes a current sampling circuit CM1 and a voltage sampling circuit VM1. The current sampling circuit CM1 and the voltage sampling circuit VM1 can be implemented in various ways. For example, the current sampling circuit CM1 can include a current sensor, and the voltage sampling circuit VM1 can include a voltage sensor. The control unit 12 is connected to the current sampling circuit CM1 and the voltage sampling circuit VM1, respectively. The current sampling circuit CM1 collects the current signal on the DC output bus, and the voltage sampling circuit VM1 collects the voltage signal on the DC output bus.

[0044] By adjusting the resistance-inductance module RL, the current amplitude and phase can be controlled. The control unit 12 can adjust the switching frequency of the three relays S1, S2, and S3 according to load changes. When the control unit 12 closes the first relay S1, opens the second relay S2, and closes the third relay S3, the three-phase power supply and the resistance-inductance module RL form a closed loop. Standby energy is consumed by RL, reducing power consumption to less than 15W.

[0045] The two live wires S and T of the three-phase power supply are respectively connected in series to a power-on soft-start unit 11 (reactive power tuning soft-start circuit). The power-on soft-start unit 11 consists of a resistance-inductance module RL and three relays S1, S2 and S3. The control terminals g of the three relays S1, S2 and S3 are respectively connected to a control unit 12. The B and C terminals of the three-phase power supply are respectively connected to a PI-type resonant filter circuit module (inductors L2 and L3), realizing reactive power regulation control at the LC resonance point, standby power consumption less than 15W, and power-on soft-start function.

[0046] In one embodiment, there may be multiple PI-type resonant filter circuit modules, for example, Figure 4 As shown, the PI-type resonant filter circuit module includes a first inductor L1, a second inductor L2, a third inductor L3, a common-mode inductor L4, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8 and a ninth capacitor C9.

[0047] The input end of the first inductor L1 is connected to the third live wire R, and the output end is connected to the first input end 1 of the industrial mode inductor L4 through the first connection line 21; the input end of the second inductor L2 is connected to the output end of the first relay S1, and the output end is connected to the second input end 2 of the industrial mode inductor L4 through the second connection line 22; the input end of the third inductor L3 is connected to the connection point between the output end of the second relay S2 and the output end of the third relay S3, and the output end is connected to the third input end 3 of the industrial mode inductor L4 through the third connection line 23.

[0048] The two ends of the first capacitor C1 are connected to the first connection line 21 and the second connection line 22, respectively. The two ends of the second capacitor C2 are connected to the first connection line 21 and the third connection line 23, respectively. The two ends of the third capacitor C3 are connected to the second connection line 22 and the third connection line 23, respectively. The first ends of the fourth capacitor C4, the fifth capacitor C5, and the sixth capacitor C6 are connected, and the second ends of the fourth capacitor C4, the fifth capacitor C5, and the sixth capacitor C6 are connected to the first connection line 21, the second connection line 22, and the third connection line 23, respectively.

[0049] A fourth connection line 24 between the first output terminal 4 of the I-mode inductor L4 and the rectifier circuit module is connected to the first end of the seventh capacitor C7. A fifth connection line 25 between the second output terminal 5 of the I-mode inductor L4 and the rectifier circuit module is connected to the first end of the eighth capacitor C8. A sixth connection line 26 between the third output terminal 6 of the I-mode inductor L4 and the rectifier circuit module is connected to the first end of the ninth capacitor C9. The second ends of the seventh capacitor C7, the eighth capacitor C8, and the ninth capacitor C9 are connected, and this connection point is grounded.

[0050] A PI-type resonant filter circuit module is directly connected in series to the connection point of the three-phase power supply's live wire R, the first relay S1, the second relay S2, and the third relay. The PI-type resonant filter circuit module consists of three inductors L1, L2, and L3, a common-mode inductor L4, and capacitors C1, C2, C3, C4, C5, C6, and C7, C8, and C9. The three inductors L1, L2, and L3 can be identical, and the capacitors C1, C2, C3, C4, C5, C6, and C7, C8, and C9 can all have equal values. The PI-type resonant filter circuit module implements PI-type resonance, impedance matching, and power factor correction for three-phase power. The PI-type resonant filter circuit filters out grid interference sources. Its LC resonates, creating an impedance state that filters out harmonics from the 2nd to the 40th order, keeping the THD (Total Harmonic Distortion) of the 2nd to 40th order harmonics for each phase current below 5%, meeting national standards.

[0051] In one embodiment, there may be multiple types of rectifier circuit modules. For example, Figure 4 As shown, the rectifier circuit module includes a three-phase rectifier bridge and a capacitor component; the three bridge arms of the three-phase rectifier bridge are respectively connected to the fourth connection line 24, the fifth connection line 25 and the sixth connection line 26; the first output end of the three-phase rectifier bridge is connected to the positive end of the DC output bus, and the second output end is connected to the negative end of the DC output bus; the capacitor component is connected in parallel to the first output end and the second output end of the three-phase rectifier bridge.

[0052] The capacitor assembly includes a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12 and a thirteenth capacitor C13; the tenth capacitor C10 and the twelfth capacitor C12 are connected in series to form a first capacitor circuit, and the two ends of the first capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; the eleventh capacitor C11 and the thirteenth capacitor C13 are connected in series to form a second capacitor circuit, and the two ends of the second capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; wherein, the connection between the tenth capacitor C10 and the twelfth capacitor C12 is connected to the connection between the eleventh capacitor C11 and the thirteenth capacitor C12.

[0053] There are many types of three-phase rectifier bridges. For example, a three-phase uncontrolled rectifier bridge consists of six electrodes (D1, D2, D3, D4, D5, and D6), and a capacitor assembly (C10, C11, C12, and C14) performs filtering and shaping to meet load requirements. The three-phase rectifier bridge (composed of diodes D1, D2, D3, D4, D5, and D6) and the capacitor assembly (composed of capacitors C10, C11, C12, and C14) convert alternating current (AC) to direct current (DC), enabling energy conversion and transmission in the power factor correction circuit for use by the load.

[0054] The harmonic suppression device in the above embodiment realizes power factor correction and reactive power regulation of the three-phase power supply, so that the THD of the 2nd to 40th harmonic currents of each phase current is less than 5%, meeting the requirements of international harmonic standards and the standard requirement of standby power consumption less than 15W; it is lower in cost, simpler to control, and more reliable than conventional APFC solutions.

[0055] In one embodiment, the present disclosure provides a harmonic suppression method based on the harmonic suppression device in the above embodiment, which is executed in a control unit; the load includes a load motor. Figure 5 FIG. 1 is a flow chart of an embodiment of a harmonic suppression method according to the present disclosure, as shown in FIG. Figure 5 As shown:

[0056] Step 501 : Calculate the load frequency and harmonic suppression current according to the voltage signal and power signal on the DC output bus and the parameters of the load motor.

[0057] In one embodiment, the control unit receives a voltage signal and a power signal on the DC output bus, respectively acquired by a voltage sampling circuit and a current sampling circuit. The load motor parameters include the number of motor pole pairs, torque coefficient, d-axis and q-axis inductance and current, and motor operating frequency.

[0058] Step 502: Perform harmonic suppression processing based on the load frequency and the harmonic suppression current.

[0059] There are many ways to deal with harmonic suppression. For example, by controlling the control terminals g of the three relays, adjusting the resonance points, and injecting power harmonic suppression current i' q , realize active power compensation, realize power factor correction adjustment, etc.

[0060] In one embodiment, the harmonic suppression current includes a first axis current; and the operating frequency of the load motor and the second axis current are acquired. When the load motor is running, the control unit acquires the operating frequency and the second axis current of the load motor, and various existing acquisition methods can be used to acquire the operating frequency and the second axis current.

[0061] A first comparison process is performed on the operating frequency and the load frequency, and a third-axis current is determined based on the result of the first comparison process. For example, the third-axis current is calculated based on the result of the first comparison process and using a first PI control algorithm. The first-axis current, the second-axis current, and the third-axis current can all be q-axis currents.

[0062] A second comparison is performed on the sum of the third-axis current and the first-axis current and the second-axis current. The shaft voltage of the load motor is determined based on the result of the second comparison. For example, the shaft voltage of the load motor is calculated based on the result of the second comparison using a second PI control algorithm. The shaft voltage of the load motor includes a q-axis voltage.

[0063] like Figure 6 As shown, the load motor is a permanent magnet synchronous motor PMSM. Figure 6 The functions within the dotted box in the figure can be implemented by the control unit of the present disclosure, or the control unit can also implement Figure 6 One or more functions outside the dotted box, for example, the control unit also includes an EMF calculation module, etc. The load includes a load motor control device, and the remaining functions not implemented by the control unit can be implemented by the load motor control device.

[0064] The control unit of the present disclosure calculates the instantaneous power:

[0065]

[0066] The load frequency is calculated based on the instantaneous power P1:

[0067]

[0068] Calculate the first axis current as:

[0069]

[0070] Where n is the number of samples, which can be obtained by a software counter; I(n) is the n-th sampled current, which is obtained by sampling the current sampling circuit; U(n) is the n-th sampled voltage, which is obtained by sampling the voltage sampling circuit; and cosθ is the power coefficient.

[0071] p is the number of pole pairs of the load motor, k t is the torque coefficient, L d and i d is the d-axis inductance and current, L q and i q is the q-axis inductance and current, and ω is the operating frequency of the load motor. d 、L q 、i d 、i q are the inductance and current of the load motor d and q axes respectively, where P, k t 、L d 、L q , parameters can be obtained from the motor specification of the load motor and stored in advance. d 、i q The d and q axis currents are collected when the load motor is running, or i is obtained from the motor specification of the load motor. d 、i q ω is the motor operating frequency, which is the actual operating frequency of the load motor collected when the load motor is running.

[0072] like Figure 6 As shown, ω * For the predetermined frequency of the load motor, ω can be used * Or ω′ and ω are subjected to a first comparison process, and the third axis current is calculated according to the result of the first comparison process and the first PI control algorithm. Usually ω′ and ω are used for the first comparison process. and the first axis current i′ q The sum of the result and the second axis current i q Perform a second comparison process, and calculate the shaft voltage u of the load motor based on the result of the second comparison process and using the second PI control algorithm. q . Set the fourth axis current and the fifth axis current i d Perform a third comparison process, and calculate the shaft voltage u of the load motor according to the result of the third comparison process and using the third PI control algorithm. d .

[0073] The first PI control algorithm, the second PI control algorithm, and the third PI control algorithm may be existing PI control algorithms including P (proportional) control and I (integral) control, and may be implemented in a software manner.

[0074] Through the I_Park module and SVPWM (Space Vector Pulse Width Modulation) module, u q and u d After I-Park transformation and SVPWM processing, it is sent to IPM (Intelligent Power Module), which controls the PMSM permanent magnet synchronous motor. v and i w , for i v and i w Clark processing and Park transformation processing are performed; EMF (back electromotive force) calculation module is based on u q 、u d 、i d 、i q Calculate the ω value. The I_Park module, SVPWM module, Clark module, Park module, and EMF calculation module can be implemented using existing algorithms and methods to perform corresponding functions.

[0075] In one embodiment, the first relay, the second relay, and the third relay are controlled to be open or closed for performing resonance adjustment. When the operating frequency of the load motor is 0, the first relay, the second relay, and the third relay are controlled to be open.

[0076] Calculate the instantaneous power P1 and calculate the load frequency ω' based on the instantaneous power P1. After the load frequency stabilizes, adjust the R and L values of the resistance-inductance module by controlling the control terminals g of the second and third relays, adjust the resonance point, and make the circuit resonate and present impedance. After the resonance point is stabilized, calculate the first axis current i' q (harmonic suppression current), injected i′ q Current, i in the vector control diagram injected into the load motor q axis, so that the conduction angle β of the rectifier bridge diode becomes smaller; the rectifier bridge diode can be the rectifier bridge diode of the inverter component, or the diode in the three-phase rectifier bridge of the rectifier circuit module. The diode conduction angle β can be adjusted using existing methods to make the current waveform follow the grid power input voltage waveform and be close to a sine wave, such as Figure 7 As shown, this is the voltage waveform displayed on the screen of a device such as an oscilloscope.

[0077] The harmonic suppression device and harmonic suppression method in the above-mentioned embodiment allow the current of each phase of the three-phase power supply to pass through the PI-type adjustable resonance point filter circuit, which can adjust the input voltage, current phase, matching impedance and multiple resonance points in real time, realize three-phase power supply power factor correction and reactive power regulation, so that the THD of the 2nd to 40th harmonics of each phase current is less than 5%, meeting the national standard requirements, and the standby power consumption is less than 15W, which meets the standard requirements; the control is simple, the cost is low, and the reliability is high.

[0078] In one embodiment, Figure 8 FIG. 1 is a schematic diagram of a module according to an embodiment of a control unit of the present disclosure. Figure 8 As shown, the apparatus may include a memory 81, a processor 82, a communication interface 83, and a bus 84. The memory 81 is used to store instructions, the processor 82 is coupled to the memory 81, and the processor 82 is configured to execute the harmonic suppression method in any of the above embodiments based on the instructions stored in the memory 81.

[0079] Memory 81 can be high-speed RAM, non-volatile memory, or a memory array. Memory 81 can also be divided into blocks, and the blocks can be combined into virtual volumes according to certain rules. Processor 82 can be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the harmonic suppression method of the present disclosure.

[0080] In one embodiment, the present disclosure provides a computer-readable storage medium storing computer instructions. When the instructions are executed by a processor, the harmonic suppression method in any of the above embodiments is implemented.

[0081] In one embodiment, the present disclosure provides a power supply device, including the harmonic suppression device in the above embodiment. The power supply device is a three-phase power supply device, etc.

[0082] In one embodiment, the present disclosure provides an electrical device including the harmonic suppression device in the above embodiment. The electrical device can be of various types, such as a variable frequency air conditioner.

[0083] The harmonic suppression device, method, control unit, power supply device, electrical equipment and storage medium provided in the above embodiments allow the current of each phase of the three-phase power supply to pass through the PI-type adjustable resonant point filter circuit, which can adjust the input voltage, current phase, matching impedance and multiple resonant points in real time to achieve three-phase power factor correction and reactive power regulation, so that the THD of the 2nd to 40th harmonics of each phase current is less than 5%, meeting the national standard requirements, and the standby power consumption is less than 15W, which meets the standard requirements; the control is simple, the cost is low, and the reliability is high, which reduces the cost by at least 200 yuan compared with the conventional APFC solution.

[0084] The methods and systems of the present disclosure may be implemented in many ways. For example, the methods and systems of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above unless otherwise specified. In addition, in some embodiments, the present disclosure may also be implemented as programs recorded in a recording medium, which include machine-readable instructions for implementing the methods according to the present disclosure. Therefore, the present disclosure also covers recording media that store programs for executing the methods according to the present disclosure.

[0085] The description of the present disclosure is provided for purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the disclosed form. Many modifications and variations will be apparent to those skilled in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present disclosure and to enable those skilled in the art to understand the present disclosure and design various embodiments with various modifications suitable for specific applications.

Claims

1. A harmonic suppression device, comprising: a tuning circuit module connected to a first live wire and a second live wire of a three-phase power supply, and configured to perform resonance regulation processing on a first phase current input through the first live wire and a second phase current input through the second live wire; a PI-type resonant filter circuit module, connected to the tuning circuit module and the third live wire of the three-phase power supply, respectively, for performing harmonic filtering on the first-phase current and the second-phase current processed by the tuning circuit module, and the third-phase current input through the third live wire; a rectifier circuit module, connected to the PI-type resonant filter circuit module, for rectifying the first-phase current, the second-phase current, and the third-phase current processed by the PI-type resonant filter circuit module to obtain direct current and output it through a direct current output bus to power a load; Wherein, the tuning circuit module includes: a power-on soft start unit connected to the first live wire and the second live wire; A detection unit, used to collect voltage and current signals on the DC output bus; A control unit is used to control the power-on soft start unit to perform resonance adjustment processing according to the voltage signal and the current signal, wherein the load frequency and harmonic suppression current are calculated according to the voltage signal and the current signal on the DC output bus and the parameters of the load motor.

2. The device according to claim 1, wherein The power-on soft start unit includes: a first relay, a second relay, a third relay and a resistance-sensing unit; The input end of the first relay is connected to the first live wire, and the output end is connected to the PI type resonant filter circuit module; The second live wire is connected to the input end of the second relay, and is also connected to the input end of the third relay through the resistance-inductance unit; the output end of the second relay is connected to the output end of the third relay, and this connection point is connected to the PI-type resonant filter circuit module; The control unit is connected to the control ends of the first relay, the second relay and the third relay respectively, and is used to control the first relay, the second relay and the third relay to be opened or closed.

3. The device according to claim 2, wherein The detection unit includes: a current sampling circuit and a voltage sampling circuit; the control unit is connected to the current sampling circuit and the voltage sampling circuit respectively; The current sampling circuit is used to collect the current signal on the DC output bus; The voltage sampling circuit is used to collect the voltage signal on the DC output bus.

4. The device according to claim 2, wherein The PI type resonant filter circuit module includes: a first inductor, a second inductor, a third inductor, a common mode inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor and a ninth capacitor; The input end of the first reactor is connected to the third live wire, and the output end is connected to the first input end of the common-mode inductor via a first connection line; the input end of the second reactor is connected to the output end of the first relay, and the output end is connected to the second input end of the common-mode inductor via a second connection line; the input end of the third reactor is connected to the connection point between the output end of the second relay and the output end of the third relay, and the output end is connected to the third input end of the common-mode inductor via a third connection line; Two ends of the first capacitor are connected to the first connection line and the second connection line respectively, two ends of the second capacitor are connected to the first connection line and the third connection line respectively, and two ends of the third capacitor are connected to the second connection line and the third connection line respectively; first ends of the fourth capacitor, the fifth capacitor, and the sixth capacitor are connected, and second ends of the fourth capacitor, the fifth capacitor, and the sixth capacitor are connected to the first connection line, the second connection line, and the third connection line respectively; The fourth connection line between the first output end of the common-mode inductor and the rectifier circuit module is connected to the first end of the seventh capacitor, the fifth connection line between the second output end of the common-mode inductor and the rectifier circuit module is connected to the first end of the eighth capacitor, and the sixth connection line between the third output end of the common-mode inductor and the rectifier circuit module is connected to the first end of the ninth capacitor; the second ends of the seventh capacitor, the eighth capacitor, and the ninth capacitor are connected, and this connection point is grounded.

5. The device according to claim 4, wherein The rectifier circuit module includes: a three-phase rectifier bridge and a capacitor component; The three bridge arms of the three-phase rectifier bridge are respectively connected to the fourth connection line, the fifth connection line and the sixth connection line; the first output end of the three-phase rectifier bridge is connected to the positive end of the DC output bus, and the second output end is connected to the negative end of the DC output bus; the capacitor component is connected in parallel to the first output end and the second output end of the three-phase rectifier bridge.

6. The device according to claim 5, wherein The capacitor assembly includes: a tenth capacitor, an eleventh capacitor, a twelfth capacitor and a thirteenth capacitor; The tenth capacitor and the twelfth capacitor are connected in series to form a first capacitor circuit, and the two ends of the first capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; the eleventh capacitor and the thirteenth capacitor are connected in series to form a second capacitor circuit, and the two ends of the second capacitor circuit are respectively connected to the first output end and the second output end of the three-phase rectifier bridge; wherein, the connection between the tenth capacitor and the twelfth capacitor is connected to the connection between the eleventh capacitor and the thirteenth capacitor.

7. A harmonic suppression method based on the harmonic suppression device according to any one of claims 2 to 6, executed in a control unit; wherein: The load includes a load motor, and the harmonic suppression method includes: Calculating the load frequency and harmonic suppression current according to the voltage signal and current signal on the DC output bus and the parameters of the load motor; Harmonic suppression processing is performed based on the load frequency and the harmonic suppression current.

8. The method according to claim 7, wherein the harmonic suppression current comprises: First axis current; The performing harmonic suppression processing based on the load frequency and the harmonic suppression current includes: Obtaining the operating frequency and second axis current of the load motor; performing a first comparison process on the operating frequency and the load frequency, and determining a third axis current according to a result of the first comparison process; A second comparison process is performed on a result of summing the third axis current and the first axis current and the second axis current, and the axis voltage of the load motor is determined according to the result of the second comparison process.

9. The method according to claim 8, wherein determining the third axis current according to the result of the first comparison process comprises: Calculating the third axis current according to the result of the first comparison process and using a first PI control algorithm; Determining the shaft voltage of the load motor according to the result of the second comparison process includes: The shaft voltage of the load motor is calculated according to the result of the second comparison process and using a second PI control algorithm.

10. The method according to claim 8 or 9, wherein The first axis current, the second axis current, and the third axis current include: a q-axis current; the axis voltage of the load motor includes: a q-axis voltage.

11. The method of claim 10, comprising: The load frequency is calculated as: = ； The first axis current is calculated as: ； Where n is the number of sampling times, is the nth sampling current, is the nth sampling voltage, p is the number of pole pairs of the load motor, is the torque coefficient, L d and i d is the d-axis inductance and current, L q and i q is the q-axis inductance and current, is the operating frequency of the load motor.

12. The method according to any one of claims 7 to 11, further comprising: Controlling the first relay, the second relay and the third relay to be opened or closed for performing resonance adjustment; Wherein, when the operating frequency of the load motor is 0, the first relay, the second relay and the third relay are controlled to be disconnected.

13. A control unit comprising: Memory; and a processor coupled to the memory, wherein the processor is configured to execute the method according to any one of claims 7 to 12 based on instructions stored in the memory. 14 . A computer-readable storage medium storing computer instructions, wherein the instructions are executed by a processor to execute the method according to claim 7 .

15. A power supply device comprising: The harmonic suppression device according to any one of claims 1 to 6.

16. An electrical device comprising: The harmonic suppression device according to any one of claims 1 to 6.

17. The electrical device according to claim 16, wherein: The electrical equipment includes: a variable frequency air conditioner.

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