Dynamic voltage regulation method of bidirectional DCDC converter

Abstract

The invention relates to the technical field of power electronics, and discloses a dynamic voltage regulation method of a bidirectional DCDC converter, which comprises the following steps: step 1, establishing a data acquisition module, a data analysis module, an early warning module and a control module; step 2, taking the data analysis module as a calculation center, and calculating to obtain a current regulation index Wzl of the converter, a switch closing regulation index Pzr of the converter and a stability optimization coefficient Hzj of the converter; 3, an early warning module designs a preset threshold value of an index according to historical data of the converter, data calculated by the data analysis module is transmitted to the early warning module through a network to be compared with the preset threshold value, and when the threshold value is exceeded, a corresponding alarm signal is sent out; and 4, a troubleshooting module carries out converter troubleshooting according to preset threshold comparison information of the early warning module, and through the steps, unnecessary energy loss of the converter can be reduced, and the stability of the whole system can be enhanced while the working efficiency of the converter is improved.

Description

Technical Field

[0001] The invention relates to the technical field of power electronics, and in particular to a dynamic voltage regulation method for a bidirectional DCDC converter. Background Art

[0002] Bidirectional DCDC converters are widely used in new energy industries, such as electric vehicles, solar energy systems, and energy storage systems. In these applications, voltage stability is crucial because unstable voltage may cause equipment performance degradation or even damage. However, traditional bidirectional DCDC converters have obvious deficiencies in voltage stability and poor efficiency. Due to the large current of the switch tube and the small relative current of the machine, the soft switching control mode is difficult to achieve. In addition, in high-power converters (above 5kW), the machine current is relatively small, and reliable soft switching control cannot be achieved, which further affects the voltage stability. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies in the prior art, the present invention provides a dynamic voltage regulation method for a bidirectional DCDC converter, which has the advantages of high stability and efficiency and solves the problems of poor stability and low efficiency.

[0005] (II) Technical solution

[0006] To achieve the above object, the present invention provides the following technical solution: a dynamic voltage regulation method for a bidirectional DCDC converter, comprising the following steps:

[0007] Step 1: Establish data acquisition module, data analysis module, early warning module and control module;

[0008] Step 2: Using the data analysis module as the calculation center, calculate the current regulation index Wzl of the converter, the switch closing regulation index Pzr of the converter and the converter stability optimization coefficient Hzj;

[0009] Step 3: The early warning module sets a preset threshold value for the design indicator based on the historical data of the converter, and transmits the data calculated by the data analysis module to the early warning module through the network for comparison with the preset threshold value. When the threshold value is exceeded, a corresponding alarm signal is issued;

[0010] Step 4: The fault detection module performs converter fault detection based on the preset threshold comparison information of the early warning module.

[0011] Preferably, the data acquisition module is used to collect data, and the data acquisition module includes an initialization interface data unit, an input data unit and an output data unit. The initialization interface data unit collects initialization interface data through AJAX request and online interface, the input data unit collects current and voltage input data through sensors or sampling circuits, and the output data unit collects current and voltage output data through online monitoring equipment and sensors. The initialization interface data unit, input data unit and output data unit are connected to the data analysis module through a network.

[0012] Preferably, the data analysis module includes a current regulation unit of the converter, a switch closure regulation unit of the converter and a stability optimization unit of the converter. The current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data. The switch closure regulation unit of the converter calculates the switch closure regulation index Pzr of the converter according to the initialization interface data, current and voltage input data. The converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data. The data analysis module is connected to the early warning module through a network.

[0013] Preferably, the initialization interface data unit counts and numbers the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient according to the initialization interface data characteristics, and the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient are numbered as U la ,I a , f, e.

[0014] Preferably, the input data unit counts and numbers the controller active response efficiency, DC side voltage and grid voltage according to the current and voltage input data characteristics, and the controller active response efficiency and DC side voltage are numbered as V, U lb , the grid voltages are numbered as U1, U2, U3, ...U n , where the maximum and minimum values ​​of the grid voltage are numbered as U mx , U mi .

[0015] Preferably, the output data unit counts and numbers the amplitudes of the actual output current and the converter port voltage according to the current and voltage output data characteristics, and the amplitudes of the actual output current and the converter port voltage are numbered as I c , U lg .

[0016] Preferably, the current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is:

[0017] Wzl=V*(I a -I c )-k*∫(I a -I c )

[0018] In the formula, Wzl represents the current regulation index of the converter, I a represents the reference current, V represents the controller's active response efficiency, I c represents the actual output current, and k represents the loss coefficient during current transmission.

[0019] Preferably, the switch closing regulation unit of the converter calculates the switch closing regulation index Pzr of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is:

[0020]

[0021] In the formula, Pzr represents the switch closing regulation index of the converter, U la , f represent the reference voltage and switching frequency respectively, U1, U2, U3, ...U n Indicates the grid voltage, U mx , U mi Respectively represent the maximum and minimum values ​​of the grid voltage, It represents the average value of the grid voltage, and n represents the number of times the grid voltage is counted.

[0022] Preferably, the converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data, and the calculation formula is:

[0023]

[0024] In the formula, Hzj represents the converter stability optimization coefficient, U la represents the reference voltage, e represents the reactive power-voltage droop coefficient, U lg Indicates the amplitude of the converter port voltage.

[0025] Preferably, the coordination process between the early warning module and the fault troubleshooting module is:

[0026] When the early warning module detects that the current regulation index Wzl of the converter exceeds the preset threshold, it means that the output current of the converter deviates from the expected value. The fault troubleshooting module receives the early warning information and automatically checks whether there is a sudden load change, sensor failure or control loop problem.

[0027] When the early warning module detects that the switch closing regulation index Pzr of the converter exceeds the preset threshold, it means that the converter cannot respond to the load change correctly. The fault troubleshooting module receives the early warning information and automatically checks whether there is a problem with the converter's indication PWM signal generation or a switch device failure;

[0028] When the converter stability optimization coefficient Hzj exceeds the preset threshold, it means that the system cannot maintain voltage stability. The fault detection module receives the early warning information and automatically checks the connection status of the power grid and the parameter settings of the control system.

[0029] Compared with the prior art, the present invention provides a dynamic voltage regulation method for a bidirectional DCDC converter, which has the following beneficial effects:

[0030] 1. The present invention calculates the current regulation index Wzl of the converter, and the active response efficiency and the loss coefficient in the current transmission process are comprehensively considered in the calculation formula. The addition of the active response efficiency helps to improve the response speed of the system to load changes, so that the converter can adapt to the dynamic changes of the power grid and the load more quickly. The addition of the loss coefficient in the current transmission process helps to compensate for these current losses in the regulation process, thereby increasing the accuracy of current regulation. By calculating the current regulation index Wzl of the converter in real time, the fluctuation of the system in the face of load changes or power grid fluctuations can be reduced by comparison with a preset threshold, thereby improving the stability of the entire system.

[0031] 2. The present invention calculates the switch closing adjustment index Pzr of the converter, and the automatic substitution of parameters helps to obtain the optimal closing time, thereby reducing the current impact on the power grid during the switch operation, reducing the electromagnetic interference and equipment pressure caused by the switch action, and after optimizing the switch closing time, it can also reduce unnecessary energy loss, improve the working efficiency of the converter, and enhance the stability of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of 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.

[0034] See also Figure 1 , a dynamic voltage regulation method for a bidirectional DCDC converter, comprising the following steps:

[0035] Step 1: Establish data acquisition module, data analysis module, early warning module and control module;

[0036] Step 2: Using the data analysis module as the calculation center, calculate the current regulation index Wzl of the converter, the switch closing regulation index Pzr of the converter and the converter stability optimization coefficient Hzj;

[0037] Step 3: The early warning module sets a preset threshold value for the design indicator based on the historical data of the converter, and transmits the data calculated by the data analysis module to the early warning module through the network for comparison with the preset threshold value. When the threshold value is exceeded, a corresponding alarm signal is issued;

[0038] Step 4: The fault detection module performs converter fault detection based on the preset threshold comparison information of the early warning module.

[0039] The data acquisition module is used to collect data. The data acquisition module includes an initialization interface data unit, an input data unit and an output data unit. The initialization interface data unit collects initialization interface data through AJAX requests and online interfaces. The input data unit collects current and voltage input data through sensors or sampling circuits. The output data unit collects current and voltage output data through online monitoring equipment and sensors. The initialization interface data unit, the input data unit and the output data unit are connected to the data analysis module through a network.

[0040] The data analysis module includes a current regulation unit of the converter, a switch closure regulation unit of the converter and a stability optimization unit of the converter. The current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data. The switch closure regulation unit of the converter calculates the switch closure regulation index Pzr of the converter according to the initialization interface data, current and voltage input data. The converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data. The data analysis module is connected to the early warning module through a network.

[0041] The initialization interface data unit counts and numbers the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient according to the initialization interface data characteristics, and the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient are numbered as U la ,I a , f, e.

[0042] The input data unit counts and numbers the controller active response efficiency, DC side voltage and grid voltage according to the current and voltage input data characteristics. The controller active response efficiency and DC side voltage are numbered as V, U lb , the grid voltages are numbered as U1, U2, U3, ...Un , where the maximum and minimum values ​​of the grid voltage are numbered as U mx , U mi .

[0043] The output data unit counts and numbers the amplitudes of the actual output current and the voltage at the converter port according to the current and voltage output data characteristics. The amplitudes of the actual output current and the voltage at the converter port are numbered as I c , U lg ,By counting and numbering the actual output current and port voltage amplitude, the actual ,operating state of the converter system can be accurately captured, thereby making the subsequent ,current regulation index calculation more accurate, and improving the ,precision of current and voltage regulation.

[0044] The current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is:

[0045] Wzl=V*(I a -I c )-k*∫(I a -I c )

[0046] In the formula, Wzl represents the current regulation index of the converter, I a represents the reference current, V represents the controller's active response efficiency, I c represents the actual output current, and k represents the loss coefficient during current transmission.

[0047] The advantages are: by calculating the current regulation index Wzl of the converter, the active response efficiency and the loss coefficient in the current transmission process are integrated in the calculation formula. The addition of the active response efficiency helps to improve the system's response speed to load changes, so that the converter can adapt to the dynamic changes of the power grid and load more quickly. The addition of the loss coefficient in the current transmission process helps to compensate for these current losses during the regulation process, thereby increasing the accuracy of current regulation. By calculating the current regulation index Wzl of the converter in real time, the system can reduce fluctuations in the face of load changes or power grid fluctuations by comparing with the preset threshold, thereby improving the stability of the entire system.

[0048] The switch closing regulation unit of the converter calculates the switch closing regulation index Pzr of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is:

[0049]

[0050] In the formula, Pzr represents the switch closing regulation index of the converter, U la, f represent the reference voltage and switching frequency respectively, U1, U2, U3, ...U n Indicates the grid voltage, U mx , U mi Respectively represent the maximum and minimum values ​​of the grid voltage, It represents the average value of the grid voltage, and n represents the number of times the grid voltage is counted.

[0051] The advantages are: by calculating the switch closing regulation index Pzr of the converter, the automatic substitution of parameters helps to obtain the best closing moment, thereby reducing the current impact on the power grid during the switch operation, reducing the electromagnetic interference and equipment pressure caused by the switch action, and after optimizing the switch closing moment, it can also reduce unnecessary energy loss, improve the working efficiency of the converter, and enhance the stability of the entire system.

[0052] The converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data. The calculation formula is:

[0053]

[0054] In the formula, Hzj represents the converter stability optimization coefficient, U la represents the reference voltage, e represents the reactive power-voltage droop coefficient, U lg Indicates the amplitude of the converter port voltage.

[0055] The advantages are: by introducing the reactive-voltage droop coefficient into the calculation formula of the converter stability optimization coefficient Hzj, the relationship between reactive power and voltage can be effectively adjusted. When the reactive power increases, the voltage will decrease accordingly, thereby maintaining the stability of the system. This real-time adjustment mechanism using the calculation formula helps to reduce voltage fluctuations and improve the stability of the system.

[0056] The coordination process between the early warning module and the troubleshooting module is as follows:

[0057] When the early warning module detects that the current regulation index Wzl of the converter exceeds the preset threshold, it indicates that the output current of the converter deviates from the expected value (the early warning module can monitor the operating status of the converter in real time and evaluate its performance through the current regulation index. When it is found that the output current does not match the expected value, the early warning mechanism can be triggered. This automatic mechanism helps to timely discover potential problems within the converter system and avoid the expansion of faults). When the fault detection module receives the early warning information, it will automatically check whether there is a sudden load change, sensor failure or control loop problem (electrical equipment overheating, damage or reduced efficiency). After receiving the early warning information, the fault detection module can automatically start a series of diagnostic procedures to determine the specific cause of the problem. This automated troubleshooting method not only improves the diagnostic efficiency, but also reduces the need for human intervention and reduces the complexity of operation.

[0058] When the early warning module detects that the switch closure regulation index Pzr of the converter exceeds the preset threshold, it indicates that the converter cannot correctly respond to load changes (the function of the early warning module is to determine whether the converter can adapt to load changes by monitoring the switch closure regulation index. When the index exceeds the threshold, it indicates that there is a response problem in the converter's internal system and needs to be checked immediately). When the fault detection module receives the early warning information, it will automatically check whether there is a problem with the converter's indication PWM signal generation or a switching device failure. By accurately locating the source of the problem, repairs or adjustments can be carried out more quickly, saving costs and effective resources.

[0059] When the converter stability optimization coefficient Hzj exceeds the preset threshold, it means that the system cannot maintain voltage stability. The fault detection module receives the early warning information and automatically checks the connection status of the power grid and the parameter settings of the control system. By comprehensively checking the power grid, it can ensure that the root cause of the power grid problem is found and appropriate solutions are taken.

[0060] The advantages are: the coordination between the early warning module and the troubleshooting module can monitor in real time and quickly respond to abnormal conditions of the converter. The automated troubleshooting reduces human intervention and improves diagnostic efficiency. The precise location of the source of the problem helps to solve the problem in a targeted manner, thereby comprehensively checking potential influencing factors to ensure the long-term stable operation of the system.

[0061] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A dynamic voltage regulation method for a bidirectional DCDC converter, characterized in that: The following steps are involved: Step 1: Establish data acquisition module, data analysis module, early warning module and control module; Step 2: Using the data analysis module as the calculation center, calculate the current regulation index Wzl of the converter, the switch closing regulation index Pzr of the converter and the converter stability optimization coefficient Hzj; Step 3: The early warning module sets a preset threshold value for the design indicator based on the historical data of the converter, and transmits the data calculated by the data analysis module to the early warning module through the network for comparison with the preset threshold value. When the threshold value is exceeded, a corresponding alarm signal is issued; Step 4: The fault detection module performs converter fault detection based on the preset threshold comparison information of the early warning module.

2. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 1, characterized in that: The data acquisition module is used to collect data. The data acquisition module includes an initialization interface data unit, an input data unit and an output data unit. The initialization interface data unit collects initialization interface data through AJAX requests and online interfaces. The input data unit collects current and voltage input data through sensors or sampling circuits. The output data unit collects current and voltage output data through online monitoring equipment and sensors. The initialization interface data unit, the input data unit and the output data unit are connected to the data analysis module through a network.

3. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 1, characterized in that: The data analysis module includes a current regulation unit of the converter, a switch closure regulation unit of the converter and a stability optimization unit of the converter. The current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data. The switch closure regulation unit of the converter calculates the switch closure regulation index Pzr of the converter according to the initialization interface data, current and voltage input data. The converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data. The data analysis module is connected to the early warning module through a network.

4. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 1, characterized in that: The initialization interface data unit counts and numbers the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient according to the initialization interface data characteristics, and the reference voltage, reference current, switching frequency and reactive power-voltage droop coefficient are numbered as U la ,I a , f, e.

5. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 1, characterized in that: The input data unit counts and numbers the controller active response efficiency, DC side voltage and grid voltage according to the current and voltage input data characteristics, and the controller active response efficiency and DC side voltage are numbered as V, Ul b , the grid voltages are numbered as U1, U2, U3, ...U n , where the maximum and minimum values ​​of the grid voltage are numbered as U mx , U mi .

6. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 1, characterized in that: The output data unit counts and numbers the amplitudes of the actual output current and the voltage at the converter port according to the current and voltage output data characteristics. The amplitudes of the actual output current and the voltage at the converter port are numbered as I c , U lg .

7. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 4, characterized in that: The current regulation unit of the converter calculates the current regulation index Wzl of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is: Pattern=V*(I a -AND c )-k*∫(I a -AND c ) In the formula, Wzl represents the current regulation index of the converter, I a represents the reference current, V represents the controller's active response efficiency, I c represents the actual output current, and k represents the loss coefficient during current transmission.

8. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 4, characterized in that: The switch closing adjustment unit of the converter calculates the switch closing adjustment index Pzr of the converter according to the initialization interface data, current and voltage input data, and the calculation formula is: In the formula, Pzr represents the switch closing regulation index of the converter, U la , f represent the reference voltage and switching frequency respectively, U1, U2, U3, ...U n Indicates the grid voltage, U mx , U mi Respectively represent the maximum and minimum values ​​of the grid voltage, It represents the average value of the grid voltage, and n represents the number of times the grid voltage is counted.

9. The dynamic voltage regulation method of the bidirectional DCDC converter according to claim 5, characterized in that: The converter stability optimization unit calculates the converter stability optimization coefficient Hzj according to the initialization interface data, current and voltage output data, and the calculation formula is: In the formula, Hzj represents the converter stability optimization coefficient, U la represents the reference voltage, e represents the reactive power-voltage droop coefficient, U lg Indicates the amplitude of the converter port voltage.

10. The dynamic voltage regulation method of a bidirectional DCDC converter according to claim 1, characterized in that: The coordination process between the early warning module and the fault troubleshooting module is as follows: When the early warning module detects that the current regulation index Wzl of the converter exceeds the preset threshold, it means that the output current of the converter deviates from the expected value. The fault troubleshooting module receives the early warning information and automatically checks whether there is a sudden load change, sensor failure or control loop problem. When the early warning module detects that the switch closing regulation index Pzr of the converter exceeds the preset threshold, it means that the converter cannot respond to the load change correctly. The fault troubleshooting module receives the early warning information and automatically checks whether there is a problem with the converter's indication PWM signal generation or a switch device failure; When the converter stability optimization coefficient Hzj exceeds the preset threshold, it means that the system cannot maintain voltage stability. The fault detection module receives the early warning information and automatically checks the connection status of the power grid and the parameter settings of the control system.

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