Current automatic equalization fault control method and system

Abstract

The invention relates to a current automatic equalization fault control method and system. The automatic current-sharing fault control method comprises the following steps: acquiring the maximum output power of each power supply, the maximum voltage allowed by a load, the minimum load voltage value when a system has no power supply fault, the minimum threshold voltage after the system has the power supply fault, and the maximum output current value of each power supply, and setting the initial current given value of each power supply; electrifying the equipment, and collecting the real-time voltage of each power supply; establishing a current compensation model for each power supply, and obtaining a current given maximum value of each power supply; calculating a threshold voltage and a voltage regulation width of each power supply; establishing an automatic current balancing model for each power supply, and acquiring a current given value of each power supply; and adjusting the current output of each power supply to a current given value and outputting the current given value. According to the invention, through a current compensation algorithm, the overall maximum output current can be increased after a power supply fault, so that the output power is not reduced, and buffer time is provided for system maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply systems, and in particular, to a method and system for automatically balancing current faults. Background Art

[0002] Grid-connected power supply of high-voltage power supplies can increase the output current of the power supply system to meet the needs of high-load devices. However, due to the different internal resistances of each power supply, some power supplies may output at full load, while some power supplies may have an output current of 0 or very small, thus losing the meaning of grid-connected power supply. There are many existing technologies and solutions. One is the master-slave control method, that is, one of them is selected as the master, and the rest are slaves. The master distributes the current of each one to achieve balance. The disadvantage of this method is that once the master is damaged, the system will not be able to work, and the later maintenance is troublesome. When a power supply needs to be replaced, it is necessary to confirm the master-slave identity of each one and make settings. Moreover, additional hardware circuits need to be established for the control of the slaves, such as 485 communication or feedback adjustment circuits, etc., which increases the cost. Another method is to use a third-party hardware control circuit to coordinately control the output current of each power supply to make it balanced. This solution solves the problem of setting the power supply in the master-slave mode and instead is set by the third-party circuit. However, the disadvantage is that it increases the control cost because the third party needs to control the working current of each power supply, that is, it needs to establish a circuit connection with each power supply. And once the third-party detection circuit is damaged or fails, it means that the system will lose the balancing function.

[0003] In the existing power supply automatic current sharing system, when one of the power supplies fails, the expected output power requirement is often not met. For example, a certain load has a rated current of 100 mA and is driven by 5 power supplies, with each getting 20 mA. When one of them fails, if the remaining 4 still output at a current of 20 mA each, the output power requirement will not be met, resulting in a reduction in system performance. One can only wait for the maintenance personnel to replace the power supply. During this waiting period for maintenance, for some industries with high real-time requirements, this is fatal. The existing solutions usually add a third-party detection circuit. When it detects that one of the power supplies fails, the third-party circuit calculates that each of the remaining 4 power supplies should get 100 mA / 4 = 25 mA, and then raises the current of the remaining 4 power supplies through communication or other interaction methods. This solution depends on the third-party circuit, increasing the cost. If the third-party detection circuit breaks down, it is also of no avail. Or some solutions are to set the master-slave mode, set a master, and other slaves, to notify the other power supplies to increase the current. However, the master-slave mode system depends on the master, and the power supply needs to be configured in the master-slave mode, which is not conducive to maintenance. And once the master is damaged, it is of no avail.

[0004] Therefore, it is necessary to provide a method and system for automatic current equalization fault control that does not require setting the master-slave mode, each power supply works independently, and does not require a third-party detection circuit for coordinated control. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a method and system for automatic current equalization fault control.

[0006] The technical solution of the present invention is as follows:

[0007] A method for automatic current sharing fault control, the method for automatic current sharing fault control includes:

[0008] T1: Obtain the maximum output power P of each power supply max , obtain the highest voltage V allowed by the load max , obtain the minimum load voltage value V when there is no power supply fault in the system b , obtain the lowest threshold voltage V after a power supply fault occurs in the system min , obtain the maximum output current value I of each power supply max , set the initial current given value I0 of each power supply;

[0009] T2: Power on the device and collect the real-time voltage V of each power supply r ;

[0010] T3: Each power supply independently establishes a current compensation model and obtains its own maximum current given value I x :

[0011]

[0012] T4: Calculate the threshold voltage V of each power supply x and the voltage adjustment width V seg :

[0013]

[0014] T5: Each power supply independently establishes a current automatic equalization model and obtains its own current given value I g :

[0015]

[0016] T6: Adjust the current output of each power supply to its respective obtained current given value I g and output.

[0017] As a further improvement of the present invention, the maximum output power P of each power supply max is the same, and the initial current given value I0 of each power supply is the same.

[0018] As a further improvement of the present invention, the calculation of the initial current set value I0 is as follows:

[0019] I0 = I n / n,

[0020] wherein, I n is the rated current required by the load, and n is the number of power supplies connected in parallel.

[0021] As a further improvement of the present invention, the rated current of the power supply is I e , satisfying:

[0022] I e ≥ I0.

[0023] A control system based on the above current automatic current sharing fault control method includes a load and multiple power supplies for supplying power to the load. The multiple power supplies are connected in parallel to supply power to the load. The power supply includes an output end electrically connected to the load and a current sharing control algorithm component electrically connected to the output end. The current sharing control algorithm component makes the current set value I g output by each power supply the same.

[0024] As a further improvement of the present invention, the current sharing control algorithm component includes a sampling module, a current compensation algorithm module, a current equalization algorithm module, and a control module. The sampling module is electrically connected to the current compensation algorithm module, the current equalization algorithm module, and the control module. The current compensation algorithm module is electrically connected to the current equalization algorithm module. The current equalization algorithm module is electrically connected to the control module. The control module is electrically connected to the output end.

[0025] As a further improvement of the present invention, the control module is a closed-loop controller.

[0026] As a further improvement of the present invention, the sampling module includes a current sampling circuit and a voltage sampling circuit. The voltage sampling circuit samples the real-time voltage V r at the output end and feeds it back to the current compensation algorithm module and the current equalization algorithm module. The current sampling circuit samples the real-time current at the output end and feeds it back to the control module.

[0027] As a further improvement of the present invention, the current compensation algorithm module is a computer or an industrial control computer, and the current equalization algorithm module is a computer or an industrial control computer.

[0028] As a further improvement of the present invention, a circuit breaker is provided between the power supply and the load.

[0029] According to the present invention of the above solution, the beneficial effect of the present invention is that:

[0030] The present invention provides a method and system for automatic current balancing fault control. Each power supply is provided with a balancing control algorithm to collect its own current and voltage data and calculate the current set value I respectively. g To achieve the current balancing effect among power supplies, each power supply works independently without setting a master-slave mode and without the need for a third-party detection circuit for coordinated control, effectively reducing the usage cost. Brief Description of the Drawings

[0031] Figure 1 is a flowchart of the automatic current balancing control method of the present invention;

[0032] Figure 2 is a schematic structural diagram of the present invention;

[0033] Figure 3 is a schematic structural diagram inside the power supply of the control system of the present invention;

[0034] Figure 4 is a flowchart of the fault control method of the present invention;

[0035] Figure 5 is a schematic structural diagram inside the power supply of the fault control system of the present invention. Detailed Embodiments

[0036] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0037] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations. In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0039] See Figure 1 , the present invention provides a method for automatically controlling current balance, and the control method includes:

[0040] S1: Obtain the maximum output power P of each power supply max and the highest voltage V allowed by the load max , set the initial current set value I0 of each power supply. Preferably, the maximum output power P of each power supply max is the same, that is, the specifications of each power supply are the same. This can not only avoid collecting information for each power supply and calculating their respective initial current set values I0, effectively simplify the overall work process and reduce the overall work intensity, but also effectively improve the control over the automatic current balance control and improve the effect of current balance control; since each power supply is connected in parallel to supply power to the load, the voltage of each power supply is the same, and the voltage of each power supply is the same as the voltage across the load, that is, the highest allowable working voltage of each power supply is the highest voltage V allowed by the load max , the different rated currents of different loads determine the difference in the initial current set value I0 of the power supply. Since it is a current sharing system, the output current of each power supply should be the same, that is, the initial current set value I0 of each power supply is the same. Therefore, the rated current of the load is the product of the initial current set value I0 of the power supply and the number of power supplies connected in parallel. The calculation of the initial current set value I0 is:

[0041] I0 = I n / n,

[0042] where, I n is the rated current required by the load, and n is the number of power supplies connected in parallel; taking the rated current I of the load n as 100 mA and five power supplies connected in parallel as an example, the initial current set value I0 set for each power supply is 20 mA;

[0043] where, in order to ensure that each power supply can work normally, it is necessary to satisfy that the rated current I of each power supply e is greater than or equal to the initial current set value I0, that is, to satisfy:

[0044] I e ≥ I0.

[0045] S2: Calculate the threshold voltage V of each power supply x and the voltage regulation width V seg :

[0046]

[0047] Since the maximum output power P of the power supply max and the initial current set value I0 are determined and fixed values, the threshold voltage V of the power supply x can also be determined, and the voltage regulation width V seg is the difference voltage between the highest working voltage V allowed by the power supply max and the threshold voltage V of the power supply; x

[0048] S3: Power on the device and collect the real-time voltage V of each power supply r ;

[0049] S4: Each power supply establishes its own current automatic balancing model and obtains its own current set value I g :

[0050]

[0051] After the power supply starts to be powered on, the current closed-loop controller of the high-voltage power supply starts to work, increasing the output current. Initially, the current closed-loop is carried out according to I0. At this time, the current closed-loop controller will work, the output current of the high-voltage power supply will increase, and the output voltage will also increase. The actual voltage value is detected in real time inside the high-voltage power supply. If it does not reach the threshold V x , at this time, the given value I g given by the equalization algorithm remains unchanged at the initial value I0, allowing the current closed-loop controller to close the output current to I0. At this time, each power supply works in the current closed-loop state, and the current of each is balanced, and the balanced value is I0;

[0052] Once it is detected that the actual voltage V r exceeds V x , at this time, the current closed-loop controller does not work. The result of this is that the current value of each will be uncertain because it is grid-connected power supply, and the current allocated to each is unbalanced and depends on the internal resistance of the power supply. At this time, the given value needs to be adjusted immediately, that is, to reduce I g , to prompt the current closed-loop controller to work, so that the high-voltage power supply works in the current closed-loop state. According to the formula, the given value I g is obtained, and it can be seen that I g is always lower than I0;

[0053] S5: Adjust the current output of each power supply to the respectively obtained current set value I g and output. Since the power supplies are in parallel power supply, the real-time voltage V collected by each power supply r is the same, and the calculated current set value I g is also the same, that is, it can ensure that the output current of each power supply is the same, realizing the balanced control of the parallel power supply current of the power supplies. Of course, the established automatic current balance model can be applied to any load, and the applicable range is wide.

[0054] The present invention adopts a structure in which each power supply works independently. An equalization control algorithm is provided in each power supply to collect the respective current and voltage data and calculate the current set value I g to achieve the current equalization effect among the power supplies, without setting a master-slave mode and without the need for a third-party detection circuit to coordinate and control, effectively reducing the use cost, and being applicable to any load, with a wide applicable range and improving the use compatibility.

[0055] The present invention provides a first embodiment. Five power supplies supply the same load and the specifications of each power supply are the same. According to the load characteristics, the parameters are set as follows:

[0056] The rated current I of the load n = 100 mA;

[0057] The initial current set value I0 of the power supply = 20 mA;

[0058] The maximum output power P of the power supply max = 980 W;

[0059] The highest working voltage V allowed by the power supply max = 50 kV;

[0060] The threshold voltage V of the power supply x = 49 kV;

[0061] The voltage regulation width V seg = 1 kV;

[0062] After power-on, the initial detection finds that the output current of each power supply is I0, that is, 20 mA, and the real-time voltage V r is 47 kV, which does not reach the 49 kV of the power supply threshold voltage V x , and each power supply is in a current equalization state. However, as the working conditions change and the load characteristics change, the voltage will continue to rise, and when it reaches the power supply threshold voltage V xPreviously, the power supply was still in the current equalization state because the output capacity of the power supply was sufficient at that time. However, once the voltage exceeded 49 KV, the output capacity of the power supply would be unable to meet the requirements, resulting in different currents for each power supply. At this time, the current set value I was calculated according to the current automatic equalization model. g , mainly to reduce I g to make the power supply operate within the allowable power range. Since all power supplies are powered in parallel, the real-time voltage V detected by each power supply r is the same. Therefore, the current set value I calculated according to the current automatic equalization model g is also the same, achieving automatic current equalization control.

[0063] The present invention provides a second embodiment. Five power supplies supply the same load and the specifications of each power supply are different. According to the load characteristics, the parameters are set as follows:

[0064] The rated current I of the load n = 100 mA;

[0065] The initial current set value I0 of the power supply = 20 mA;

[0066] The maximum output power P of power supply one max = 980 W;

[0067] The maximum output power P of power supply two max = 1000 W;

[0068] The maximum output power P of power supply three max = 1100 W;

[0069] The maximum output power P of power supply four max = 1250 W;

[0070] The maximum output power P of power supply five max = 1400 W;

[0071] The highest working voltage V allowed for the power supply max = 50 KV;

[0072] Since the maximum output powers P of the five power supplies max are all different, the smallest maximum output power P among them is selected max to calculate the power supply threshold voltage V x . After calculation, the power supply threshold voltage V x = 49 KV;

[0073] The voltage regulation width V seg = 1 KV.

[0074] See Figure 2 and Figure 3The present invention provides a control system, including a load and a plurality of power supplies for supplying power to the load, wherein the plurality of power supplies are connected in parallel to supply power to the load, the power supply includes an output terminal electrically connected to the load and a current balancing component electrically connected to the output terminal, and the current balancing component realizes a current given value I output by each power supply. g Similarly, the current sharing components inside each power supply calculate their respective current given values ​​I g The load is then powered by the output terminal.

[0075] As an embodiment of the present invention, the current balancing component includes a sampling module, a current balancing algorithm module and a control module. The sampling module is electrically connected to the current balancing algorithm module and the control module. The current balancing algorithm module is electrically connected to the control module. The control module is electrically connected to the output end. The sampling module samples the system in real time and feeds back the sampling signal to the current balancing algorithm module and the control module. The current balancing algorithm module calculates the current given value I according to the collected sampling signal. g And the current given value I g The signal is transmitted to the control module, which obtains the output current value based on the signals fed back by the sampling module and the current balancing algorithm module, and supplies current to the load through the output end.

[0076] As an embodiment of the present invention, the control module is a closed-loop controller. Preferably, the control module adopts a software closed-loop controller, such as a PID controller. The sampling module includes a current sampling circuit and a voltage sampling circuit. The voltage sampling circuit collects the real-time voltage V at the output end. r And feed back to the current balancing algorithm module. The current sampling circuit collects the real-time current at the output end and feeds back to the control module. The current balancing algorithm module is a computer or industrial computer. It forms a feedback loop inside the power supply to realize current PID control, so that each power supply works in the current closed-loop mode, and finally provides balanced current to the load.

[0077] As an embodiment of the present invention, a circuit breaker is provided between the power supply and the load. When the load changes, the staff can reasonably increase or decrease the number of parallel power supplies by closing or disconnecting the circuit breaker between each power supply and the load according to the specific needs of the load, thereby improving the compatibility and practicality of the system. At the same time, when a power supply fails, the circuit breaker between the power supply and the load can be disconnected in time to make the power supply disconnected from the parallel state, thereby avoiding unnecessary impact on the overall power supply.

[0078] In the existing power automatic current sharing system, when one of the power supplies fails, the expected output power requirement is often not met. For example, for a certain load with a rated current of 100 mA, driven by 5 power supplies, each gets 20 mA. When one of them fails, if the remaining 4 still output at 20 mA each, the output power requirement cannot be met, resulting in a decrease in system performance. One has to wait for the maintenance personnel to replace the power supply. During the waiting period for maintenance, for some industries with high real-time requirements, this is fatal. The existing solutions usually involve adding a third-party detection circuit. When it detects that one of the power supplies fails, the third-party circuit calculates that each of the remaining 4 power supplies should get 100 mA / 4 = 25 mA, and then raises the current of the remaining 4 power supplies through communication or other interaction methods. This solution relies on the third-party circuit, increasing costs, and if the third-party detection circuit breaks down, it is of no avail. Or some solutions set a master-slave mode, set a master, and other slaves to notify other power supplies to increase the current. However, the master-slave mode system relies on the master, and the power supplies need to be configured with the master-slave mode, which is not conducive to maintenance. Moreover, once the master is damaged, it is of no avail.

[0079] See Figure 4 , the present invention provides a fault control method, and the fault control method includes:

[0080] T1: Obtain the maximum output power P of each power supply max , obtain the highest voltage V allowed by the load max , obtain the minimum load voltage value V when there is no power supply failure in the system b , obtain the lowest threshold voltage V after a power supply failure occurs in the system min , obtain the maximum output current value I of each power supply max , set the initial current given value I0 of each power supply. Preferably, the maximum output power P of each power supply max is the same, that is, the specifications of each power supply are the same. This can not only avoid collecting information for each power supply and calculating their respective initial current given values I0, effectively simplifying the overall work process and reducing the overall work intensity, but also effectively improve the control over the automatic current equalization control and improve the effect of current equalization control; since each power supply is connected in parallel to supply power to the load, the voltage of each power supply is the same, and the voltage of each power supply is the same as the voltage across the load, that is, the highest working voltage allowed for each power supply is the highest voltage V allowed by the load max , the different rated currents of different loads determine the different initial current given values I0 of the power supplies. Since it is a current sharing system, the output current of each power supply should be the same, that is, the initial current given values I0 of each power supply are the same. Therefore, the rated current of the load is the product of the initial current given value I0 of the power supply and the number of parallel power supplies. The calculation of the initial current given value I0 is:

[0081] I0 = I n / n,

[0082] wherein, I n is the rated current required by the load, and n is the number of parallel power supplies; taking the rated current I n of the load as 100 mA and five power supplies in parallel as an example, the initial current set value I0 of each power supply is 20 mA;

[0083] wherein, in order to enable each power supply to work properly, it is necessary to satisfy that the rated current I e of each power supply is greater than or equal to the initial current set value I0, that is, it satisfies:

[0084] I e ≥ I0.

[0085] T2: The device is powered on, and the real-time voltage V r of each power supply is collected;

[0086] T3: Each power supply establishes its own current compensation model and obtains its own maximum current set value I x :

[0087]

[0088] wherein, the lowest threshold voltage V min after a power supply failure in the system means that when a power supply fails, the voltage on the load will decrease, and the lowest threshold voltage allowed to decrease after the system is the lowest threshold voltage. When it is lower than this value, the maintenance personnel must be notified to replace the power supply, that is, the system gives an alarm. After the system is powered on, when no power supply fails, the detected real-time voltage V r of the power supply all exceeds the minimum load voltage value V b , then the maximum current set value I x is the initial current set value I0 of the power supply. When a power supply fails, the load voltage decreases. At this time, the detected real-time voltage V r will be lower than the minimum load voltage value V b . At this time, the current compensation model can reasonably adjust the maximum current set value I x of the power supply, so that the system has a buffer time after a power supply failure, and the system will not stop working or work poorly. When the number of damaged power supplies is large, resulting in the detected real-time voltage V r of the power supply being lower than the lowest threshold voltage V min , then the system cannot work, and the maintenance personnel should be notified to repair and replace it in time.

[0089] T4: Calculate the threshold voltage V x and the voltage adjustment width V seg of each power supply:

[0090]

[0091] Since the maximum output power P of the power supply max and the maximum current set value I x have been determined, the threshold voltage V of the power supply x can also be determined. The voltage regulation width V seg is the difference voltage between the highest operating voltage V allowed by the power supply max and the threshold voltage V of the power supply x ;

[0092] T5: Each power supply establishes an automatic current equalization model respectively to obtain its own current set value I g :

[0093]

[0094] After the power supply starts to be powered on, the current closed-loop controller of the high-voltage power supply starts to work, increasing the output current. Initially, the current closed-loop is carried out according to I x . At this time, the current closed-loop controller will work, the output current of the high-voltage power supply will increase, and the output voltage will also increase. The actual voltage value inside the high-voltage power supply is detected in real time. If the threshold V x is not reached, the given value I g given by the equalization algorithm remains the maximum value I x unchanged, allowing the current closed-loop controller to close the output current to I x . At this time, each power supply works in the current closed-loop state, and the current of each is balanced, and the balanced value is I x .

[0095] Once the actual voltage V r is detected to exceed V x , the current closed-loop controller does not work at this time. The result of this is that the current value of each unit will be uncertain because it is grid-connected power supply, and the current allocated to each unit is unbalanced and depends on the internal resistance of the power supply. At this time, the given value needs to be adjusted immediately, that is, to reduce I g to prompt the current closed-loop controller to work and make the high-voltage power supply work in the current closed-loop state. According to the formula, the given value I g is obtained, and it can be seen that I g is always lower than I x ;

[0096] T6: Adjust the current output of each power supply to the respective obtained current set value I g and output it. Since the power supplies are in parallel power supply, the real-time voltage V r collected by each power supply is the same, and the calculated current set value Ig It is the same, that is, it can ensure that the output current of each power supply is the same, achieving the balanced control of the grid-connected power supply current. Of course, the established automatic current balance model can be applied to any load, with a wide range of applications.

[0097] The present invention provides a third embodiment where 5 power supplies supply the same load and the specifications of each power supply are the same. During operation, a power supply failure occurs. Before the power supply failure, according to the load characteristics, the following parameters are set:

[0098] Rated current I of the load n = 100 mA;

[0099] Initial current given value I0 of the power supply = 20 mA;

[0100] Maximum current given value I of the power supply x = 20 mA;

[0101] Maximum output current value I of the power supply max = 33 mA;

[0102] Maximum output power P of the power supply max = 980 W;

[0103] Highest working voltage V allowed by the power supply max = 50 KV;

[0104] Minimum load voltage value V when there is no power supply failure in the system b = 39 KV;

[0105] Lowest threshold voltage V after a power supply failure occurs in the system min = 26 KV;

[0106] Threshold voltage V of the power supply x = 49 KV;

[0107] Voltage regulation width V seg = 1 KV.

[0108] When one power supply fails, only 4 power supplies are working. At this time, the load voltage will decrease. The measured load voltage V r = 34 KV. According to the formula, the maximum current given value I of the power supply is calculated x = 25 mA. It can be seen that it has exceeded the previously set 20 mA. As the working conditions change, the voltage will fluctuate within a certain range. For example, the voltage will increase, but it will not be higher than V b . When the voltage increases, according to the formula, I x will decrease moderately, but it is still higher than I0 = 20 mA. At this time, I x will fluctuate around 25 mA. Then, the calculated Ix Substitute into the current automatic equalization model to obtain the current set value I g to achieve the current equalization effect among power supplies;

[0109] When two power supplies fail, only 3 power supplies are working. At this time, the measured load voltage V r = 26.5 KV. Calculate the maximum allowable power supply current set value I x = 32.5 mA according to the formula. Similarly, as the working conditions change, the voltage will also have a certain range of fluctuations;

[0110] When three power supplies fail, at this time the load voltage V r is lower than V min . According to the formula, the maximum output current value I max of the power supply should be maintained at 33 mA for current output. At this time, the system alarms to notify the maintenance personnel to replace the power supply.

[0111] The present invention can set the corresponding V min , I max and V b according to the specific load conditions, thereby providing flexibility in use. Through the current compensation algorithm, the overall maximum output current can be increased after the power supply fails, so as to maintain the output power without reduction, providing a buffer time for system maintenance. Of course, even if one power supply is damaged, the power supply needs to be replaced according to the system requirements to ensure the stability and reliability of the system.

[0112] Refer to Figure 2 and Figure 5 . The present invention provides a fault control system, including a load and multiple power supplies for supplying power to the load. The multiple power supplies are connected in parallel to supply power to the load. The power supply includes an output end electrically connected to the load and a current sharing control algorithm component electrically connected to the output end. The current sharing control algorithm component makes the current set value I g of each power supply output the same. The current sharing control algorithm component inside each power supply calculates its own current set value I g , and supplies current to the load in a current sharing manner through the output end.

[0113] As an embodiment of the present invention, the current sharing control algorithm component includes a sampling module, a current compensation algorithm module, a current equalization algorithm module, and a control module. The sampling module is electrically connected to both the current equalization algorithm module and the control module. The current compensation algorithm module is electrically connected to the current equalization algorithm module. The current equalization algorithm module is electrically connected to the control module. The control module is electrically connected to the output end. The sampling module samples the system in real time and feeds the sampling signal back to the current compensation algorithm module, the current equalization algorithm module, and the control module. The current compensation algorithm module calculates the maximum allowable power supply current set value I xThe power supply current is given a maximum value I x The current is transmitted to the current balancing algorithm module, which calculates the current given value I according to the collected sampling signal. g And the current given value I g The signal is transmitted to the control module, which obtains the output current value based on the signals fed back by the sampling module and the current balancing algorithm module, and supplies current to the load through the output end.

[0114] As an embodiment of the present invention, the control module is a closed-loop controller. Preferably, the control module adopts a software closed-loop controller, such as a PID controller. The sampling module includes a current sampling circuit and a voltage sampling circuit. The voltage sampling circuit collects the real-time voltage V at the output end. r And feed back to the current balancing algorithm module, the current sampling circuit collects the real-time current at the output end and feeds back to the control module, the current compensation algorithm module is a computer or an industrial computer, and the current balancing algorithm module is a computer or an industrial computer. A feedback loop is formed inside the power supply to realize current PID control, so that each power supply works in the current closed-loop mode, and finally provides balanced current to the load.

[0115] As an embodiment of the present invention, a circuit breaker is provided between the power supply and the load. When the load changes, the staff can reasonably increase or decrease the number of parallel power supplies by closing or disconnecting the circuit breaker between each power supply and the load according to the specific needs of the load, thereby improving the compatibility and practicality of the system. At the same time, when a power supply fails, the circuit breaker between the power supply and the load can be disconnected in time to make the power supply disconnected from the parallel state, thereby avoiding unnecessary impact on the overall power supply.

[0116] In summary, the present invention provides a current automatic balancing fault control method and system, which adopts an independent working structure of each power supply, and each power supply is provided with a balancing control algorithm to collect the current and voltage data of each power supply, and calculate the current given value I gTo achieve the current balancing effect between the power supplies, there is no need to set the master-slave mode, and no need for third-party detection circuit coordination control, which effectively reduces the cost of use, and can be applied to any load, with a wide range of applications and improved compatibility; a feedback loop is formed inside the power supply to realize current PID control, so that each power supply works in the current closed-loop mode, and finally provides balanced current to the load; the staff can reasonably increase or decrease the number of parallel power supplies by closing or turning off the circuit breaker between each power supply and the load according to the specific needs of the load, thereby improving the compatibility and practicality of the system. At the same time, when a power supply fails, the circuit breaker between the power supply and the load can be turned off in time to make the power supply out of the parallel state, avoiding unnecessary impact on the overall power supply; through the current compensation algorithm, the overall maximum output current can be increased after the power supply fails, thereby maintaining the output power without reduction, providing buffer time for system maintenance, and improving the stability and reliability of the overall work.

[0117] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for automatically controlling current equalization faults, characterized in that, The described automatic current sharing fault control method includes: T1: Obtain the maximum output power P of each power supply max , the maximum output power P of each power supply max is the same, obtain the highest voltage V allowed by the load max , obtain the minimum load voltage value V when there is no power supply fault in the system b , obtain the lowest threshold voltage V after a power supply fault occurs in the system min , obtain the maximum output current value I of each power supply max , set the initial current given value I0 of each power supply; T2: The device is powered on, and the real-time voltage V of each power supply is collected r ; T3: Each power supply independently establishes a current compensation model and obtains its own maximum given current I x : T4: Calculate the threshold voltage V of each power supply x and the voltage regulation width V seg : T5: Each power supply independently establishes a current automatic balancing model and obtains its own current set value I g : T6: Adjust the current output of each power supply to the respective derived current setpoint I g and output it.

2. The automatic current sharing fault control method according to claim 1, wherein The maximum output power P of each of the power supplies max is the same, and the initial current set value I0 of each of the power supplies is the same.

3. The current automatic current sharing fault control method according to claim 2, wherein The calculation of the initial current given value I0 is as follows: I0 = I n / n, Wherein, I n is the rated current required by the load, and n is the number of power supplies connected in parallel.

4. The current automatic current sharing fault control method according to claim 3, wherein The rated current of the power supply is I e , which satisfies: I e ≥ I0.

5. A control system based on the current automatic current sharing fault control method according to any one of claims 1-4, characterized in that, It includes a load and multiple power supplies for powering the load. The multiple power supplies are connected in parallel to power the load. The power supply includes an output end electrically connected to the load and a current sharing control algorithm component electrically connected to the output end. The current sharing control algorithm component realizes the current set value I output by each power supply g to be the same.

6. The control system according to claim 5, wherein The current sharing control algorithm component includes a sampling module, a current compensation algorithm module, a current equalization algorithm module, and a control module. The sampling module is electrically connected to the current compensation algorithm module, the current equalization algorithm module, and the control module. The current compensation algorithm module is electrically connected to the current equalization algorithm module. The current equalization algorithm module is electrically connected to the control module. The control module is electrically connected to the output terminal.

7. The control system according to claim 6, wherein The control module is a closed-loop controller.

8. The control system according to claim 6, characterized in that, The sampling module includes a current sampling circuit and a voltage sampling circuit. The voltage sampling circuit samples the real-time voltage V at the output end r and feeds it back to the current compensation algorithm module and the current equalization algorithm module. The current sampling circuit samples the real-time current at the output end and feeds it back to the control module.

9. The control system according to claim 6, characterized in that, The current compensation algorithm module is a computer or an industrial control computer, and the current equalization algorithm module is a computer or an industrial control computer.

10. The control system according to claim 5, characterized in that, A circuit breaker is provided between the power supply and the load.

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