Power adjusting method and device, air conditioner, storage medium and electronic equipment

Abstract

The invention discloses a power adjusting method and device, an air conditioner, a storage medium and electronic equipment. The method is applied to a frequency converter, the frequency converter comprises at least two rectifier modules, each rectifier module comprises a rectifier bridge and a PFC circuit, and the method comprises the following steps: determining a reference voltage of each rectifier module according to a power demand of a load and a droop control coefficient of each rectifier module; wherein the droop control coefficient is preset virtual impedance of the rectifier module; and determining the duty ratio of a power switch tube in the PFC circuit of each rectification module according to the reference voltage, and controlling the on-off of the power switch tube according to the duty ratio. According to the invention, the power utilization rate of the rectifier module can be improved, the overload loss of the rectifier module is reduced, and the high efficiency and stability of the frequency converter are ensured.

Description

Technical Field

[0001] The present invention relates to the field of electronic power technology, and in particular to a power regulation method, device, air conditioner, storage medium and electronic equipment. Background Art

[0002] In existing power systems and power electronic equipment, when the load power demand changes greatly, a fixed power margin is generally set to cope with the instantaneous load increase, but this often leads to waste of equipment resources and reduced efficiency.

[0003] In addition, in inverters for high-power electrical equipment, it is often necessary to use multiple rectifier modules in parallel to supply power in order to meet the load power requirements and ensure power supply reliability. In inverters that use multiple rectifier modules in parallel, the currents of the multiple rectifier modules need to be accurately distributed. The existing current distribution control method cannot accurately adjust the output power of each rectifier module according to the actual load power requirements, resulting in a waste of rectifier module power.

[0004] Currently, no effective solution has been proposed for the problem that the current distribution control method of multiple rectifier modules in the inverter in the prior art cannot accurately adjust the output power of each rectifier module according to the actual load power demand, resulting in power waste of the rectifier modules. Summary of the invention

[0005] The embodiments of the present invention provide a power regulation method, device, air conditioner, storage medium and electronic device to solve the problem that the current distribution control method of multiple rectifier modules in the inverter in the prior art cannot accurately adjust the output power of each rectifier module according to the actual load power demand, resulting in power waste of the rectifier module.

[0006] To solve the above technical problems, the present invention provides a power regulation method, which is applied to a frequency converter, wherein the frequency converter includes at least two rectifier modules, and the rectifier modules include a rectifier bridge and a PFC circuit. The method includes:

[0007] Determining the reference voltage of each rectifier module according to the power demand of the load and the droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module;

[0008] The duty cycle of the power switch tube in the PFC circuit of each rectifier module is determined according to the reference voltage, and the power switch tube is controlled to be turned on and off according to the duty cycle.

[0009] Further, the reference voltage of each rectifier module is determined according to the power demand of the load and the droop control coefficient of each rectifier module, including:

[0010] Determine the given voltage of each rectifier module according to the power demand of the load;

[0011] Obtain the detection voltage and detection current of each rectifier module;

[0012] Calculating the product of the detection current and the droop control coefficient to obtain a virtual voltage drop;

[0013] The difference between the given voltage of the rectifier module and the virtual voltage drop is calculated to obtain the reference voltage.

[0014] Furthermore, after calculating the difference between the given voltage of the rectifier module and the virtual voltage drop to obtain the reference voltage, the method further includes:

[0015] Calculate the internal voltage drop of each rectifier module and the average value of the difference between the given voltage of all rectifier modules and the bus voltage;

[0016] Performing proportional integration on the internal voltage drop of each rectifier module and the average value to obtain a reference voltage correction amount;

[0017] The reference voltage is corrected based on the reference voltage correction amount to obtain a final reference voltage.

[0018] Furthermore, when the internal voltage drop of each rectifier module is proportionally integrated with the average value to obtain the reference voltage correction amount, it is implemented according to the following formula:

[0019]

[0020] Among them, U i is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

[0021] Further, determining the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage includes:

[0022] Determine a reference current according to the reference voltage, the detection voltage and the total resistance of the rectifier module;

[0023] The duty cycle is calculated according to the reference current and the detection current.

[0024] Furthermore, the method further comprises:

[0025] The droop control coefficient of each rectifier module is adjusted according to the deviation between its output power and its maximum power.

[0026] Furthermore, the droop control coefficient of each rectifier module is adjusted according to the deviation between the output power of each rectifier module and its maximum power, including:

[0027] Determine whether the deviation between the output power of each rectifier module and its maximum power is less than a preset threshold;

[0028] If yes, the droop control coefficient of the rectifier module is controlled to decrease.

[0029] Furthermore, the method further comprises:

[0030] Detect the internal temperature of each rectifier module;

[0031] When the internal temperature of the rectifier module is higher than a preset threshold, the droop control coefficient of the rectifier module is controlled to decrease.

[0032] Furthermore, the method further comprises:

[0033] The timing starts after the rectifier module is started;

[0034] The droop control coefficient of the rectifier module is controlled to rotate at every preset time interval.

[0035] The present invention also provides a power regulation device, which is applied to a frequency converter, wherein the frequency converter includes at least two rectifier modules, and the rectifier modules include a rectifier bridge and a PFC circuit. The device includes:

[0036] A calculation module, used to determine the reference voltage of each rectifier module according to the power demand of the load and the droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module;

[0037] The control module is used to determine the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage, and control the on and off of the power switch tube according to the duty cycle.

[0038] The present invention also provides a frequency converter, the frequency converter comprises at least two rectifier modules, the rectifier modules comprise a rectifier bridge and a PFC circuit, and the above-mentioned power regulating device.

[0039] The present invention also provides an air conditioner, comprising the above-mentioned inverter.

[0040] The present invention also provides a computer-readable storage medium on which a computer program is stored, and the program implements the power regulation method when executed by a processor.

[0041] The present invention also provides an electronic device, comprising:

[0042] one or more processors;

[0043] The storage device is used to store one or more programs, and when the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned power regulation method.

[0044] By applying the technical solution of the present invention, the virtual impedance of each rectifier module is pre-set as the droop control coefficient, and the reference voltage of each rectifier module is determined by droop control. Droop control is a control strategy commonly used in power systems, especially in distributed power generation systems. It simulates the droop characteristics between frequency-power and voltage-reactive power of traditional generators, so that distributed power sources can work like synchronous generators, thereby realizing parallel operation and load sharing under non-communication conditions. This embodiment controls the output power of two or more rectifier modules through the droop control method to meet the power demand of electrical equipment, and dynamically adjusts the output power of the inverter according to the actual load power demand to avoid unnecessary energy waste, ensuring that the equipment provides rapid response and power boost when the load power demand increases. It is suitable for power electronic equipment, smart grid, renewable energy system and other occasions, and can improve the power utilization of the rectifier module, reduce the overload loss of the rectifier module, and ensure the high efficiency and stability of the inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The topological structure diagram of the existing inverter using a single rectifier module;

[0046] Figure 2 A topological structure diagram of a frequency converter with multiple rectifier modules connected in parallel according to an embodiment of the present invention;

[0047] Figure 3 is a flow chart of a power regulation method according to an embodiment of the present invention;

[0048] Figure 4 is an equivalent circuit diagram of a rectifier module according to an embodiment of the present invention;

[0049] Figure 5 A control principle diagram according to an embodiment of the present invention;

[0050] Figure 6 is an output current comparison diagram of a rectifier module according to a control method of an embodiment of the present invention;

[0051] Figure 7 A control principle diagram according to another embodiment of the present invention;

[0052] Figure 8 is a comparison diagram between the reference voltage correction amount and the output voltage of the rectifier module according to another embodiment of the present invention;

[0053] Fig. 9 is a structural diagram of a power regulating device according to an embodiment of the present invention;

[0054] Fig.10 FIG. 4 is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0057] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0058] It should be understood that although the terms first, second, etc. may be used to describe resistors in embodiments of the present invention, these resistors should not be limited to these terms. These terms are only used to distinguish different resistors. For example, without departing from the scope of embodiments of the present invention, a first resistor may also be referred to as a second resistor, and similarly, a second resistor may also be referred to as a first resistor.

[0059] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0060] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0061] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0062] Example 1

[0063] Figure 1 The topological structure diagram of the existing inverter using a single rectifier module is shown in FIG. Figure 1 As shown in the figure, only one rectifier module is used to provide the power required by the load. When the load power demand changes greatly, a fixed power margin is generally set to cope with the instantaneous load increase, but this often leads to waste of equipment resources and reduced efficiency. To address this problem, in the inverter of high-power electrical equipment, multiple rectifier modules are often used in parallel to supply power to meet the load power demand and ensure power supply reliability. Figure 2 : is a topological structure diagram of a frequency converter with multiple rectifier modules connected in parallel according to an embodiment of the present invention, such as Figure 2 As shown, the inverter includes at least two rectifier modules 10 and an inverter module 20, the rectifier module 10 includes a rectifier bridge 101 and a PFC circuit 102, the PFC circuit 102 includes an inductor L1, a power switch tube Q and a diode D, and a bus capacitor C1 is provided between the rectifier module 10 and the inverter module 20. In an inverter using multiple rectifier modules in parallel, the currents of the multiple rectifier modules need to be accurately distributed, and the existing current distribution control method cannot accurately adjust the output power of each rectifier module according to the actual load power demand, resulting in a waste of the power of the rectifier module.

[0064] Aiming at the problem that the current distribution control method of multiple rectifier modules in the inverter in the prior art cannot accurately adjust the output power of each rectifier module according to the actual load power demand, resulting in power waste of the rectifier module, this embodiment provides a power regulation method. Figure 3 is a flow chart of a power regulation method according to an embodiment of the present invention. Figure 3 As shown, the power regulation method includes:

[0065] S101, determining a reference voltage of each rectifier module according to a power demand of a load and a droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module.

[0066] In this embodiment, the number of rectifier modules is two as an example. Figure 4 is an equivalent circuit diagram of a rectifier module according to an embodiment of the present invention, such as Figure 4 As shown, the given voltage of the first rectifier module is V1', the virtual impedance (i.e., the droop control coefficient) is K1, the line impedance is R1, and the current is I1. The given voltage of the second rectifier module is V2', the reference voltage is Vref1, the virtual impedance (i.e., the droop control coefficient) is K2, the line impedance is R2, the current is I2, the reference voltage is Vref2, the load is RL, and the voltage across the load, i.e., the bus voltage, is V L .

[0067] S102, determining the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage of each rectifier module, and controlling the on and off of the power switch tube in the PFC circuit of each rectifier module according to the duty cycle of the power switch tube.

[0068] The power regulation method of this embodiment pre-sets the virtual impedance of each rectifier module as a droop control coefficient, and uses droop control to determine the reference voltage of each rectifier module. Droop control is a control strategy commonly used in power systems, especially in distributed power generation systems. It simulates the droop characteristics between frequency-power and voltage-reactive power of traditional generators, so that distributed power sources can work like synchronous generators, thereby realizing parallel operation and load sharing under non-communication conditions. This embodiment controls the output power of two or more rectifier modules through the droop control method to meet the power demand of electrical equipment, and dynamically adjusts the output power of the inverter according to the actual load power demand to avoid unnecessary energy waste, ensuring that the equipment provides rapid response and power boost when the load power demand increases. It is suitable for power electronic equipment, smart grid, renewable energy system and other occasions, and can improve the power utilization of the rectifier module, reduce the overload loss of the rectifier module, and ensure the high efficiency and stability of the inverter.

[0069] According to the above mentioned Figure 4 As shown in the equivalent circuit diagram, the reference voltage Vref can be obtained by the given voltage V' and the droop control coefficient K i By using the droop control coefficient K i As a virtual impedance, we can get

[0070] Vref i =V' i -I i K i (1)

[0071] Among them, Vref i is the reference voltage of the ith rectifier module, V' i is the given voltage of the i-th rectifier module.

[0072] Depend on Figure 4 It can be seen that the bus voltage V of each rectifier module L It can be obtained by subtracting the voltage drop IR on the line from the reference voltage Vref, that is:

[0073] V L =Vref i -I i R i (2)

[0074] Among them, R i is the line impedance of the i-th rectifier module.

[0075] According to the bus voltage is equal, then:

[0076] Vref1-I1R1=Vref2-I2R2 (3)

[0077] Substituting formula (1) into formula (3) can be simplified to obtain:

[0078] I1(K1+R1)=I2(K2+R2) (4)

[0079] By using formula (4), we can obtain:

[0080]

[0081] Because the line impedance on each line is very small and can be ignored relative to the virtual impedance, we have:

[0082]

[0083] It can be seen that the current of each rectifier module is inversely proportional to the droop control coefficient.

[0084] Figure 5 is a control principle diagram according to an embodiment of the present invention. Based on the above quantitative relationship, as shown in FIG. Figure 5 As shown, the reference voltage of each rectifier module is determined according to the power demand of the load and the droop control coefficient of each rectifier module, including: determining the given voltage V' of each rectifier module according to the power demand of the load i ; Get the detection voltage V of each rectifier module i and the detection current I i ; Calculate the detection current I i and droop control coefficient K i The virtual voltage drop I is obtained by multiplying i K i ; Calculate the given voltage V' of the rectifier module i and virtual voltage drop I i K i The reference voltage Vref is obtained by i .

[0085] like Figure 5 As shown, the duty cycle of the power switch tube in the PFC circuit of each rectifier module is determined according to the reference voltage, including: the voltage control module determines the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage Vref i , Detection voltage V i The reference current Irefi is determined by the total resistance of the rectifier module; the current control module calculates the duty cycle D according to the reference current Irefi and the detection current Ii.

[0086] Figure 6 : is an output current comparison diagram of the rectifier module according to the control method of the embodiment of the present invention. In this embodiment, the number of rectifier modules is two, K1:K2=1:2. Figure 6 As shown, when the load power demand changes, both rectifier modules can achieve fast response.

[0087] According to the bus voltage V L The calculation formula is:

[0088] V L =V' i -I i (K i +R i );Vrefi=V' i -I i K i (7)

[0089] It can be seen that the above droop control will cause a large voltage drop in the bus voltage based on the given voltage, which will affect the control accuracy. Therefore, the reference voltage correction value U is introduced i The reference voltage is corrected, and the corrected DC bus voltage is:

[0090] V L =V'-I i (K i +R i )+U i ;Vref i =V' i -I i K i +U i (8)

[0091] Define the internal voltage drop V of the rectifier module Oi =I i (K i +R i ), then the difference between the given voltage and the bus voltage is:

[0092] ε i =V' i -VL =V Oi -U i (9)

[0093] Assuming that there are N rectifier modules in the system, the sum of the difference between the given voltage of all modules and the bus voltage is:

[0094]

[0095] Calculate the average value of the difference between the module given voltage and the bus voltage of N rectifier modules:

[0096]

[0097] Solving the reference voltage correction value U through PI control i , then:

[0098]

[0099] Among them, U i is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

[0100] Figure 7 This is a control principle diagram according to another embodiment of the present invention. In order to avoid too large an adjustment step size, which results in reduced accuracy, as shown in FIG. Figure 7 As shown, after calculating the difference between the given voltage of the rectifier module and the virtual voltage drop and obtaining the reference voltage, the method further includes: calculating the internal voltage drop V of each rectifier module Oi The average value of the difference between the given voltage of all rectifier modules and the bus voltage The internal voltage drop V of each rectifier module Oi Proportional integration is performed with the average value to obtain the reference voltage correction value U i ; Based on the reference voltage correction amount, the reference voltage is corrected to obtain the final reference voltage: Vref i =V' i -I i K i +U i .

[0101] The internal voltage drop of each rectifier module is proportionally integrated with the average value to obtain the reference voltage correction value, which is implemented according to the following formula: Among them, Ui is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

[0102] Figure 8 FIG. 4 is a comparison diagram between the reference voltage correction amount and the output voltage of the rectifier module according to another embodiment of the present invention. Figure 8 As shown, the reference voltage correction amount can quickly respond to the output voltage change of the rectifier module and reach a steady state, indicating that the system has good stability.

[0103] In order to avoid overloading of the rectifier module, when the output power of the rectifier module is close to its maximum power, its output power must be limited. Therefore, the above method also includes: adjusting the droop control coefficient of each rectifier module according to the deviation between its output power and its maximum power; specifically, adjusting the droop control coefficient of each rectifier module according to the deviation between its output power and its maximum power includes: judging whether the deviation between the output power of each rectifier module and its maximum power is less than a preset threshold; if so, controlling the droop control coefficient of the rectifier module to decrease. The rectifier module can be set to slightly reduce the output voltage when approaching overload, and the other module will increase the output to share the load, while increasing the reliability of the system. If the output power of both rectifier modules is close to their maximum power, the rectifier modules will reduce the output power at the same time.

[0104] In order to avoid overloading of the rectifier module and causing the temperature inside the rectifier module to be too high, the above method also includes: detecting the internal temperature of each rectifier module; when the internal temperature of the rectifier module is higher than a preset threshold, controlling the droop control coefficient of the rectifier module to decrease.

[0105] In order to avoid a single rectifier module from running at high load for a long time, which affects the service life of the rectifier module, the above method also includes: starting the timing after the rectifier module is started; controlling the droop control coefficient of the rectifier module to rotate at each preset time interval. Specifically, when the number of rectifier modules is two, the droop control coefficients of the two rectifier modules are controlled to be exchanged once at each preset time interval; when the number of rectifier modules is N (N>2), the rectifier modules are sorted in order according to the numbers, and at each preset time interval, the droop control coefficient of the rectifier module numbered i+1 is replaced with the droop control coefficient of the rectifier module numbered i, and the droop control coefficient of the first rectifier module is replaced with the droop control coefficient of the rectifier module numbered N.

[0106] The power control method of this embodiment uses DSP to implement the droop control algorithm by presetting the droop control coefficient K i Optimize the load distribution, adjust the output power when the load fluctuates, monitor the balance of the output power of each module, adjust the droop control coefficient of the corresponding module, evenly distribute the power output, avoid overloading of a single module, reduce energy loss and achieve efficient operation. At the same time, the load and output power data can be adjusted in real time according to the module temperature and voltage and current monitored by the monitoring module to achieve rapid response. When the temperature is detected to be too high, adjust the droop coefficient to reduce the power output of the corresponding module, and under normal operation, the droop coefficient is rotated periodically to avoid a certain load being too large and shortening the service life of the module, ensuring the stable power output and long-term operation of the equipment.

[0107] Example 2

[0108] This embodiment provides a power regulation device, which is applied to a frequency converter. The frequency converter includes at least two rectifier modules, each of which includes a rectifier bridge and a PFC circuit. Fig. 9 is a structural diagram of a power regulation device according to an embodiment of the present invention, such as Fig. 9 The device shown comprises:

[0109] The calculation module 10 is used to determine the reference voltage of each rectifier module according to the power demand of the load and the droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module.

[0110] In this embodiment, the number of rectifier modules is two as an example. Figure 4 is an equivalent circuit diagram of a rectifier module according to an embodiment of the present invention, such as Figure 4 As shown, the given voltage of the first rectifier module is V1', the virtual impedance (i.e., the droop control coefficient) is K1, the line impedance is R1, and the current is I1. The given voltage of the second rectifier module is V2', the reference voltage is Vref1, the virtual impedance (i.e., the droop control coefficient) is K2, the line impedance is R2, the current is I2, the reference voltage is Vref2, the load is RL, and the voltage across the load, i.e., the bus voltage, is V L .

[0111] The control module 20 is used to determine the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage, and control the on and off of the power switch tube according to the duty cycle.

[0112] The power regulation device of this embodiment pre-sets the virtual impedance of each rectifier module as a droop control coefficient, and uses droop control to determine the reference voltage of each rectifier module. Droop control is a control strategy commonly used in power systems, especially in distributed power generation systems. It simulates the droop characteristics between frequency-power and voltage-reactive power of traditional generators, so that distributed power sources can work like synchronous generators, thereby realizing parallel operation and load sharing under non-communication conditions. This embodiment controls the output power of two or more rectifier modules through droop control to meet the power demand of electrical equipment, dynamically adjusts the output power of the inverter according to the actual load power demand, avoids unnecessary energy waste, and ensures that the equipment provides rapid response and power boost when the load power demand increases. It is suitable for power electronic equipment, smart grid, renewable energy system and other occasions, and can significantly improve the power utilization rate, reduce the overload loss of the rectifier module, and ensure the stability and efficiency of the inverter while improving the output power of the inverter.

[0113] According to the above mentioned Figure 4 As shown in the equivalent circuit diagram, the reference voltage Vref can be obtained by the given voltage V' and the droop control coefficient K i By using the droop control coefficient K i As a virtual impedance, we can get

[0114] Vref i =V' i -I i K i (1)

[0115] Among them, Vref i is the reference voltage of the ith rectifier module, V' i is the given voltage of the i-th rectifier module.

[0116] Depend on Figure 4 It can be seen that the bus voltage V of each rectifier module L It can be obtained by subtracting the voltage drop IR on the line from the reference voltage Vref, that is:

[0117] V L =Vref i -I i R i (2)

[0118] Among them, R i is the line impedance of the i-th rectifier module.

[0119] Based on the above quantitative relationship, as mentioned above Figure 5 As shown, the calculation module 10 is specifically used to: determine the given voltage V' of each rectifier module according to the power demand of the load i; Get the detection voltage V of each rectifier module i and the detection current I i ; Calculate the detection current I i and droop control coefficient K i The virtual voltage drop I is obtained by multiplying i K i ; Calculate the given voltage V' of the rectifier module i and virtual voltage drop I i K i The difference between i .

[0120] The control module 20 includes a voltage control module, a current control module and a control module. The voltage control module is used to adjust the reference voltage Vref of the rectifier module. i , Detection voltage V i The reference current Iref is determined by the total resistance of the rectifier module i ; The current control module is used to control the current according to the reference current Iref i , Detection current I i Calculate the duty cycle D. The PWM control module is used to control the on and off of the power switch tube Q according to the duty cycle D.

[0121] According to the bus voltage V L The calculation formula is:

[0122] V L =V' i -I i (K i +R i ); Vref i =V' i -I i K i (7)

[0123] It can be seen that the above droop control will cause a large voltage drop in the bus voltage based on the given voltage, which will affect the control accuracy. Therefore, the reference voltage correction value U is introduced i The reference voltage is corrected, and the corrected DC bus voltage is:

[0124] V L =V'-I i (K i +R i )+U i ;Vref i =V' i -I i K i +U i (8)

[0125] Define the internal voltage drop V of the rectifier moduleOi =I i (K i +R i ), then the difference between the given voltage and the bus voltage is:

[0126] ε i =V' i -V L =V Oi -U i (9)

[0127] Assuming that there are N rectifier modules in the system, the sum of the difference between the given voltage of all modules and the bus voltage is:

[0128]

[0129] Calculate the average value of the difference between the module given voltage and the bus voltage of N rectifier modules:

[0130]

[0131] Solving the reference voltage correction value U through PI control i , then:

[0132]

[0133] Among them, U i is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

[0134] In order to avoid adjusting the step size too large, which will lead to reduced accuracy, such as Figure 7 As shown, the calculation module 10 is also used to: calculate the difference between the given voltage of the rectifier module and the virtual voltage drop, and after obtaining the reference voltage, calculate the internal voltage drop V of each rectifier module. Oi The average value of the difference between the given voltage of all rectifier modules and the bus voltage The internal voltage drop V of each rectifier module Oi Proportional integration is performed with the average value to obtain the reference voltage correction value U i Based on the reference voltage correction amount, the reference voltage is corrected to obtain the final reference voltage, namely Vref i =V' i -I i K i +Ui .

[0135] The internal voltage drop of each rectifier module is proportionally integrated with the average value to obtain the reference voltage correction value, which is implemented according to the following formula: Among them, U i is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

[0136] In order to avoid overloading of the rectifier module, when the output power of the rectifier module is close to its maximum power, its output power must be limited. Therefore, the above-mentioned calculation module 10 is also used to adjust its droop control coefficient according to the deviation between the output power of each rectifier module and its maximum power; specifically, it is used to: determine whether the deviation between the output power of each rectifier module and its maximum power is less than a preset threshold; if so, control the droop control coefficient of the rectifier module to decrease. The rectifier module can be set to slightly reduce the output voltage when approaching overload, and the other module will increase the output to share the load, while increasing the reliability of the system. If the output power of both rectifier modules is close to their maximum power, the rectifier modules will reduce the output power at the same time.

[0137] In order to avoid overloading of the rectifier module and causing the temperature inside the rectifier module to be too high, the above-mentioned calculation module 10 is also used to: detect the internal temperature of each rectifier module; when the internal temperature of the rectifier module is higher than a preset threshold, control the droop control coefficient of the rectifier module to decrease.

[0138] In order to avoid a single rectifier module from running at high load for a long time, which affects the service life of the rectifier module, the above-mentioned calculation module 10 is also used to: start timing after the rectifier module is started; control the droop control coefficient of the rectifier module to rotate at each preset time interval. Specifically, when the number of rectifier modules is two, the droop control coefficients of the two rectifier modules are exchanged once at each preset time interval; when the number of rectifier modules is N (N>2), the rectifier modules are arranged in sequence according to the numbers, and at each preset time interval, the droop control coefficient of the rectifier module numbered i+1 is replaced with the droop control coefficient of the rectifier module numbered i, and the droop control coefficient of the first rectifier module is replaced with the droop control coefficient of the rectifier module numbered N.

[0139] Example 3

[0140] This embodiment provides a frequency converter, which includes at least two rectifier modules, each of which includes a rectifier bridge and a PFC circuit, and also includes the power regulation device of the above embodiment.

[0141] Example 4

[0142] This embodiment provides an air conditioner, comprising the inverter of the above embodiment.

[0143] Example 5

[0144] This embodiment provides a computer-readable storage medium on which a computer program is stored, wherein the program, when executed by a processor, implements the power regulation method of the above embodiment.

[0145] Example 6

[0146] This embodiment provides an electronic device, including: one or more processors; a storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the one or more processors implement the power regulation method of the above embodiment.

[0147] Fig.10 FIG. 1 is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Fig.10 As shown, the electronic device includes:

[0148] One or more processors 1010 and memory 1020, Fig.10 A processor 1010 is taken as an example.

[0149] The device of the power regulation method may further include: an input device 1030 and an output device 1040 .

[0150] The processor 1010, the memory 1020, the input device 1030 and the output device 1040 may be connected via a bus or other means. Fig.10 The example of connecting through bus is taken in the following.

[0151] The memory 1020 is a non-volatile computer-readable storage medium that can be used to store non-volatile software programs, non-volatile computer executable programs and modules, such as program instructions / modules corresponding to the power regulation method in the embodiment of the present invention. The processor 1010 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions and modules stored in the memory 1020, that is, implementing the above method embodiment.

[0152] The memory 1020 may include a program storage area and a data storage area, wherein the program storage area may store an application required for operating the device and at least one function; the data storage area may store data created according to the use of the power regulation device, etc. In addition, the memory 1020 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices.

[0153] The input device 1030 may receive input digital or character information and generate key signal input related to user settings and function control of the electronic device. The output device 1040 may include a display device such as a display screen.

[0154] The one or more modules are stored in the memory 1020, and when executed by the one or more processors 1010, the power regulation method in any of the above method embodiments is executed.

[0155] The electronic device product can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not described in detail in this embodiment, please refer to the method provided by the embodiment of the present invention.

[0156] The electronic device of the embodiment of the present invention exists in various forms, including but not limited to:

[0157] (1) Mobile communication devices: These devices are characterized by their mobile communication functions and their main purpose is to provide voice and data communications. These terminals include: smart phones (such as iPhone), multimedia phones, functional phones, and low-end phones.

[0158] (2) Ultra-mobile personal computer devices: These devices fall into the category of personal computers, have computing and processing capabilities, and generally also have mobile Internet access features. These terminals include: PDA, MID and UMPC devices, such as iPad.

[0159] (3) Portable entertainment devices: These devices can display and play multimedia content. They include audio and video players (such as iPods), handheld game consoles, e-books, smart toys, and portable car navigation devices.

[0160] (4) Server: A device that provides computing services. The server consists of a processor, hard disk, memory, device bus, etc. The server is similar to a general computer architecture, but because it needs to provide highly reliable services, it has higher requirements in terms of processing power, stability, reliability, security, scalability, and manageability.

[0161] (5) Other electronic devices with data interaction functions, such as televisions, large-screen cars, etc.

[0162] The device embodiments described above are merely illustrative, wherein the modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, i.e., they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0163] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0164] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power regulation method, applied to a frequency converter, wherein the frequency converter comprises at least two rectifier modules, wherein the rectifier modules comprise a rectifier bridge and a PFC circuit, wherein: The method comprises: Determining the reference voltage of each rectifier module according to the power demand of the load and the droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module; The duty cycle of the power switch tube in the PFC circuit of each rectifier module is determined according to the reference voltage, and the power switch tube is controlled to be turned on and off according to the duty cycle.

2. The method according to claim 1, characterized in that The reference voltage of each rectifier module is determined according to the power demand of the load and the droop control coefficient of each rectifier module, including: Determine the given voltage of each rectifier module according to the power demand of the load; Obtain the detection voltage and detection current of each rectifier module; Calculating the product of the detection current and the droop control coefficient to obtain a virtual voltage drop; The difference between the given voltage of the rectifier module and the virtual voltage drop is calculated to obtain the reference voltage.

3. The method according to claim 2, characterized in that After calculating the difference between the given voltage of the rectifier module and the virtual voltage drop to obtain the reference voltage, the method further includes: Calculate the internal voltage drop of each rectifier module and the average value of the difference between the given voltage of all rectifier modules and the bus voltage; Performing proportional integration on the internal voltage drop of each rectifier module and the average value to obtain a reference voltage correction amount; The reference voltage is corrected based on the reference voltage correction amount to obtain a final reference voltage.

4. The method according to claim 3, characterized in that The internal voltage drop of each rectifier module is proportionally integrated with the average value to obtain the reference voltage correction value, which is implemented according to the following formula: Among them, U i is the reference voltage correction value, Kp i is the proportional coefficient of the rectifier module, dt represents the Integrating with respect to time t, Kq i is the integral coefficient of the rectifier module, is the average value of the difference between the given voltage of all rectifier modules and the bus voltage, V Oi is the internal voltage drop of the rectifier module, and i represents the number of the rectifier module.

5. The method according to claim 2, characterized in that: Determining the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage includes: Determine a reference current according to the reference voltage, the detection voltage and the total resistance of the rectifier module; The duty cycle is calculated according to the reference current and the detection current.

6. The method according to claim 1, characterized in that The method further comprises: The droop control coefficient of each rectifier module is adjusted according to the deviation between its output power and its maximum power.

7. The method according to claim 6, characterized in that The droop control coefficient of each rectifier module is adjusted according to the deviation between its output power and its maximum power, including: Determine whether the deviation between the output power of each rectifier module and its maximum power is less than a preset threshold; If yes, the droop control coefficient of the rectifier module is controlled to decrease.

8. The method according to claim 1, characterized in that The method further comprises: Detect the internal temperature of each rectifier module; When the internal temperature of the rectifier module is higher than a preset threshold, the droop control coefficient of the rectifier module is controlled to decrease.

9. The method according to claim 1, characterized in that: The method further comprises: The timing starts after the rectifier module is started; The droop control coefficient of the rectifier module is controlled to rotate at every preset time interval.

10. A power regulation device, applied to a frequency converter, wherein the frequency converter comprises at least two rectifier modules, wherein the rectifier modules comprise a rectifier bridge and a PFC circuit, wherein: The device comprises: A calculation module, used to determine the reference voltage of each rectifier module according to the power demand of the load and the droop control coefficient of each rectifier module; wherein the droop control coefficient is a preset virtual impedance of the rectifier module; The control module is used to determine the duty cycle of the power switch tube in the PFC circuit of each rectifier module according to the reference voltage, and control the on and off of the power switch tube according to the duty cycle.

11. A frequency converter, characterized in that: The frequency converter comprises at least two rectifier modules, each of which comprises a rectifier bridge and a PFC circuit, and also comprises the power regulating device as claimed in claim 10.

12. An air conditioner, characterized in that: Including the frequency converter as claimed in claim 11.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 9 is implemented.

14. An electronic device, characterized in that: include: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the one or more processors to implement the method according to any one of claims 1 to 9.

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