Control method and device of power conversion unit, power supply system

Abstract

The application provides a control method and device of a power conversion unit, and a power supply system. The control method is applied to a power supply circuit, the power supply circuit comprises a plurality of power supply modules, each of which comprises a power conversion unit, and the control method is used for controlling each power conversion unit. The control method comprises the following steps: determining whether there is a cut-out of the power conversion unit in a power supply loop of the power supply circuit; if it is determined that there is a cut-out of the power conversion unit in the power supply loop, controlling the power conversion unit in the power supply circuit to access the power supply loop, and / or controlling and adjusting the output power of a target power conversion unit according to the number of the target power conversion units before and after the cut-out of the power conversion unit; wherein the target power conversion unit refers to the power conversion unit in the power supply loop. The application can ensure that the energy supply of the power supply loop can meet the application demand, and realize stable energy supply.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of circuit control, and more particularly relates to a control method and device of a power conversion unit and a power supply system. BACKGROUND

[0002] In order to improve the availability of the power supply system, a power supply system containing multiple power supply modules emerges as the times require.

[0003] Each power supply module will realize energy exchange with external equipment / external network by setting a power conversion unit. Specifically, in the power supply loop of the power supply system, the adjustment of energy supply can be realized by controlling the power conversion unit. In the prior art, when the power conversion unit is controlled, if the power conversion unit is cut out in the power supply loop, the output power of the power conversion unit in the power supply loop will be directly reduced. That is, when the power conversion unit is cut out in the power supply loop, the prior art directly controls the power conversion unit in the power supply loop to operate at a reduced capacity. However, after the power conversion unit operates at a reduced capacity, the energy supply of the power supply loop sometimes cannot meet the actual application requirements.

[0004] Therefore, the present application aims to provide a solution to solve the above problems. SUMMARY

[0005] The present application aims to provide a control method and device of a power conversion unit and a power supply system to solve the problem that the energy supply cannot meet the application requirements when the power conversion unit is cut out in the power supply loop in the prior art.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present application is to provide a control method of a power conversion unit, which is applied to a power supply circuit containing multiple power supply modules, each of which includes a power conversion unit, and is used to control each power conversion unit. The control method comprises the following steps:

[0007] determining whether there is a cut-out of the power conversion unit in the power supply loop of the power supply circuit;

[0008] if it is determined that there is a cut-out of the power conversion unit in the power supply loop, controlling the power conversion unit that can be connected to the power supply loop to be connected to the power supply loop, and / or controlling and adjusting the output power of the target power conversion unit according to the number of the target power conversion units before and after the cut-out of the power conversion unit; wherein the target power conversion unit refers to the power conversion unit in the power supply loop.

[0009] In a possible implementation, the control of the power conversion units in the power supply circuit that can access the power supply loop to access the power supply loop, and / or, according to the number of target power conversion units before and after the power conversion units are cut out, the output power of the target power conversion units is adjusted, comprising:

[0010] The number of power conversion units in the power supply circuit that can access the power supply loop is obtained, and a first number is obtained.

[0011] If the first number is greater than or equal to a second number, control the second number of power conversion units to access the power supply loop; the second number is the number of power conversion units cut out in the power supply loop.

[0012] If the first number is less than the second number and the first number is not zero, control the first number of power conversion units to access the power supply loop, and according to the number of power conversion units in the power supply loop after the power conversion units are accessed, the power is distributed to the target power conversion units, and the target power conversion units are controlled according to the distributed power.

[0013] If the first number is zero, according to the number of target power conversion units before and after the power conversion units are cut out, the output power of the target power conversion units is adjusted.

[0014] In a possible implementation, the determination of whether there is a cut-out of the power conversion unit in the power supply loop of the power supply circuit comprises:

[0015] The electrical parameter of the power supply loop is obtained.

[0016] If the electrical parameter changes and the change amount of the electrical parameter reaches a preset change amount within a preset time, it is determined that there is a cut-out of the power conversion unit in the power supply loop.

[0017] In a possible implementation, the determination of whether there is a cut-out of the power conversion unit in the power supply loop of the power supply circuit comprises:

[0018] The online state of the power conversion unit is obtained from the controller of the power conversion unit.

[0019] According to the online state of the power conversion unit, it is determined whether there is a cut-out of the power conversion unit in the power supply loop.

[0020] In a possible implementation, each power supply module further comprises a battery cluster, and the power conversion unit is connected to the battery cluster one by one; according to the number of target power conversion units before and after the power conversion units are cut out, the output power of the target power conversion units is adjusted, comprising:

[0021] The output power of the target power conversion unit is controlled according to the number of target power conversion units before and after the power conversion unit is cut off.

[0022] In a possible implementation, the step of controlling the output power of the target power conversion unit to the target power comprises:

[0023] The target power is determined by P1*N1=P2*N2, wherein P1 is the output power of the target power conversion unit before the power conversion unit is cut off, N1 is the number of the target power conversion units before the power conversion unit is cut off, P2 is the target power, and N2 is the number of the target power conversion units after the power conversion unit is cut off.

[0024] The output power of the target power conversion unit is controlled to the target power.

[0025] In a possible implementation, each power supply module further comprises a battery cluster, and the power conversion unit is connected to the battery cluster in one-to-one correspondence; if the target power is greater than the current output power of the target power conversion unit, before the output power of the target power conversion unit is controlled to the target power, the control method further comprises:

[0026] The temperature of the battery cluster in the power supply loop after a target process is predicted, wherein the target process is a process of adjusting the output power of the target power conversion unit to the target power.

[0027] Whether to perform amplitude limiting processing on the target power is determined according to the predicted temperature of the battery cluster.

[0028] In a possible implementation, the step of determining whether to perform amplitude limiting processing on the target power according to the predicted temperature of the battery cluster comprises:

[0029] When the predicted temperature of the battery cluster is less than a preset temperature, the amplitude limiting processing is not performed on the target power.

[0030] When the predicted temperature of the battery cluster is greater than or equal to the preset temperature, the output power of the target power conversion unit when the temperature of the battery cluster reaches the preset temperature is calculated to obtain an amplitude limiting power; the amplitude limiting processing is performed on the target power based on the amplitude limiting power.

[0031] Another aspect of the present application also provides a control device of a power conversion unit, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the control method of the power conversion unit when executing the computer program.

[0032] Still another aspect of the present application also provides a power supply system, which comprises:

[0033] The control device of the power conversion unit and the power supply circuit described above.

[0034] The power conversion unit control method and device and the power supply system provided by the application have the following advantages:

[0035] Unlike the prior art, which directly controls the power conversion unit to operate at a reduced capacity, the embodiment of the application considers controlling the power conversion unit that can be connected to the power supply circuit to be connected to the power supply circuit when detecting that the power conversion unit is disconnected. Accordingly, after connecting a proper number of power conversion units to the power supply circuit, there is no need to control the power conversion units in the power supply circuit to operate at a reduced capacity, so as to ensure that the energy supply of the power supply circuit can meet the application requirements.

[0036] It should be noted that "there is no need to control the power conversion units in the power supply circuit to operate at a reduced capacity" in the embodiment of the application specifically means that "the power conversion units in the power supply circuit before the power conversion units are connected do not need to operate at a reduced capacity, and the output power of the newly connected power conversion units in the power supply circuit only needs to be the same as the output power of the existing power conversion units in the power supply circuit". That is, according to the scheme of the embodiment of the application, the newly connected power conversion units can complete power control by directly referring to the control strategy of the existing power conversion units in the power supply circuit, so the embodiment of the application also has the effects of simple and fast control. Therefore, when the power conversion units in the power supply circuit are disconnected, the newly connected power conversion units can quickly fill the vacancy, thereby realizing stable energy supply.

[0037] In summary, the embodiment of the application can make the power conversion units in the power supply circuit maintain a rated operation state as much as possible, thereby effectively solving the problems in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0039] Figure 1 The flowchart of the power conversion unit control method provided by an embodiment of the application is shown in the figure.

[0040] Figure 2 The structure diagram of the energy storage container provided by an embodiment of the application is shown in the figure.

[0041] Figure 3 The structure diagram of the energy storage container provided by another embodiment of the application is shown in the figure.

[0042] Figure 4 The structural schematic diagram of the control device of the power conversion unit provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0043] In order to make the technical problems to be solved by the present application, the technical solutions and the beneficial effects more clearly understood, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0044] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] The control method of the power conversion unit provided by the embodiment of the present application is applied to a power supply circuit, and the power supply circuit includes a plurality of power supply modules. Each power supply module can be connected in parallel, and each power supply module is enabled to supply power to an external load together or accept external input power together. Each power supply module includes a power conversion unit, and the control method provided by the embodiment of the present application is used to control each power conversion unit, that is, each power conversion unit applies the control method provided by the embodiment of the present application. The power conversion unit can be a DC / DC unit or an energy storage converter, which is not limited in the embodiment.

[0046] Based on the above description, reference can be made to Figure 1 , Figure 1 The flowchart of the control method of the power conversion unit provided by an embodiment of the present application is shown. The control method includes:

[0047] S101: Determine whether there is a power conversion unit cutout in the power supply loop of the power supply circuit.

[0048] In the embodiment, the power supply loop refers to the loop composed of the modules in the power supply circuit which are enabled and are supplying power. That is, not all modules in the power supply circuit are in the enabled state, and therefore, there can be a power conversion unit cutout and access in the power supply loop.

[0049] In the embodiment, it can be determined in real time whether there is a power conversion unit cutout in the power supply loop of the power supply circuit, or it can be determined according to a preset time interval whether there is a power conversion unit cutout in the power supply loop of the power supply circuit, or it can be determined at a specified period or time point whether there is a power conversion unit cutout in the power supply loop of the power supply circuit, which is not described in the embodiment.

[0050] In the embodiment, the execution subject (i.e. the execution subject of the control method described in the embodiment of the application) can be directly connected with the power supply circuit and each power conversion unit to realize the state detection of the power supply circuit and the control of the power conversion unit. At this time, the embodiment can directly determine whether the power conversion unit is cut out in the power supply circuit by detecting the electrical parameters of the power supply circuit. The electrical parameters include but are not limited to output voltage, output current, output power, bus voltage, etc.

[0051] In the embodiment, each power conversion unit can be provided with a corresponding controller, and the controller corresponding to each power conversion unit is connected with the power supply circuit to realize the state detection of the power supply circuit and the control of the power conversion unit. On this basis, the execution subject (i.e. the execution subject of the control method described in the embodiment of the application) can be connected with the controllers of each power conversion unit to indirectly control the power conversion unit by sending corresponding control instructions to the controller of each power conversion unit. At this time, the embodiment can determine whether the power conversion unit is cut out in the power supply circuit by obtaining the online state detection result of the power conversion unit in the "power conversion unit corresponding controller". The online state of the power conversion unit includes online and offline, and the online of the power conversion unit means that the power conversion unit is in the access state, and the offline of the power conversion unit means that the power conversion unit is in the cut-out state.

[0052] S102: If it is determined that the power conversion unit is cut out in the power supply circuit, the power conversion unit that can access the power supply circuit in the power supply circuit is accessed to the power supply circuit, and / or the output power of the target power conversion unit is controlled according to the number of target power conversion units before and after the power conversion unit is cut out.

[0053] The target power conversion unit refers to the power conversion unit in the power supply circuit.

[0054] In the embodiment, the cut-out of the power conversion unit includes active cut-out and passive cut-out.

[0055] The active cut-out of the power conversion unit refers to the cut-out of the power conversion unit due to the control of the execution subject. For example, in some scenarios, the power conversion unit is connected to the battery cluster, and when the execution subject detects that the temperature of the battery cluster corresponding to the power conversion unit is high, the execution subject can control the power conversion unit to cut out to realize the cut-out of the battery cluster corresponding to the power conversion unit. For example, when the execution subject finds that too many power conversion units are connected to the power supply circuit, the execution subject can also control the power conversion unit to cut out. Such cut-out is the active cut-out of the power conversion unit. The power conversion unit that is actively cut out can be determined as a power conversion unit that can be connected to the power supply circuit. For example, the power conversion unit that is controlled to cut out due to the excessively high temperature of the battery cluster can be determined as a power conversion unit that can be connected to the power supply circuit when the temperature of the battery cluster decreases. The power conversion unit that is controlled to cut out due to the imbalance between energy supply and demand can be directly determined as a power conversion unit that can be connected to the power supply circuit.

[0056] The passive cut-out of the power conversion unit refers to the forced / self cut-out of the power conversion unit from the power supply circuit due to the failure of the power conversion unit to continue working in the power supply circuit or the failure of the energy source connected to the power conversion unit to continue working in the power supply circuit, which causes the power conversion unit to be forced / self cut out from the power supply circuit. The power conversion unit that is passively cut out can also be determined as a power conversion unit that can be connected to the power supply circuit after the failure of the power conversion unit or the energy source corresponding to the power conversion unit is repaired. The aforementioned energy source can be a battery cluster or a power grid, and the embodiment is not limited in this regard.

[0057] In the embodiment, if it is determined that there is a cut-out of the power conversion unit in the power supply circuit, the embodiment can control the power conversion unit that can be connected to the power supply circuit in the power supply circuit to be connected to the power supply circuit, or control the output power of the target power conversion unit according to the number of target power conversion units before and after the cut-out of the power conversion unit, or control the output power of the target power conversion unit while controlling the power conversion unit that can be connected to the power supply circuit in the power supply circuit to be connected to the power supply circuit. That is, the embodiment of the application does not directly make the target power conversion unit run at a reduced capacity, thereby avoiding that the actual energy supply cannot meet the application demand.

[0058] As can be known from the above description, unlike the method of directly controlling the power conversion unit to run at a reduced capacity in the prior art, when the cut-out of the power conversion unit is detected, the embodiment of the application considers controlling the power conversion unit that can be connected to the power supply circuit in the power supply circuit to be connected to the power supply circuit. After a proper number of power conversion units are connected to the power supply circuit, it is not necessary to control the power conversion unit in the power supply circuit to run at a reduced capacity, so as to ensure that the energy supply of the power supply circuit can meet the application demand.

[0059] It is to be noted that the "power conversion unit in the power supply circuit does not need to be de-rated" in the embodiment of the present application specifically means that "the power conversion unit in the power supply circuit does not need to be de-rated before the power conversion unit is connected, and the output power of the newly connected power conversion unit in the power supply circuit only needs to be the same as the output power of the existing power conversion unit in the power supply circuit". That is, according to the scheme of the embodiment of the present application, the newly connected power conversion unit can complete the power control by directly referring to the "control strategy of the existing power conversion unit in the power supply circuit", and thus the embodiment of the present application also has the effects of simple and fast control. Therefore, when the power conversion unit in the power supply circuit is cut off, the newly connected power conversion unit can quickly fill the vacancy, thereby realizing stable energy supply.

[0060] In summary, the embodiment of the present application can maintain the power conversion unit in the power supply circuit in a rated operation state, thereby effectively solving the problems in the prior art.

[0061] In a possible implementation, the power conversion unit that can be connected to the power supply circuit in the power supply circuit is connected to the power supply circuit, and / or the output power of the target power conversion unit is adjusted according to the number of power conversion units before and after the power conversion unit is cut off, comprising:

[0062] The number of power conversion units that can be connected to the power supply circuit in the power supply circuit is obtained, and a first number is obtained.

[0063] If the first number is greater than or equal to the second number, the second number of power conversion units is controlled to be connected to the power supply circuit. The second number is the number of power conversion units cut off in the power supply circuit.

[0064] If the first number is less than the second number and the first number is not zero, the first number of power conversion units is controlled to be connected to the power supply circuit, and the power conversion units in the power supply circuit after the power conversion unit is connected are allocated power according to the number of power conversion units, and the target power conversion unit is controlled according to the allocated power.

[0065] If the first number is zero, the output power of the target power conversion unit is adjusted according to the number of power conversion units before and after the power conversion unit is cut off.

[0066] In the embodiment, if it is determined that there is a cut-off of the power conversion unit in the power supply circuit, the number of power conversion units that can be connected to the power supply circuit in the power supply circuit is obtained, and a first number is obtained. The first number is used to determine "whether the existing available power conversion unit can meet the energy supply demand without de-rating".

[0067] In the embodiment, if the first quantity is greater than or equal to the second quantity, it indicates that the existing available power conversion units can meet the application requirement, and the second quantity of power conversion units can be directly controlled to access the power supply loop, and the quantity of target power conversion units is not changed relative to the quantity of target power conversion units before the power conversion units are cut off. That is, the existing power conversion units in the power supply loop before the second quantity of power conversion units access the power supply loop do not need to be operated at a reduced capacity, and the newly accessed power conversion units can be directly operated according to the existing output power. The existing output power refers to the output power of the existing power conversion units in the power supply loop before the second quantity of power conversion units access the power supply loop.

[0068] In the embodiment, if the first quantity is less than the second quantity and the first quantity is not zero, it indicates that there are power conversion units that can access the power supply loop in the power supply circuit, but the power conversion units that can access the power supply loop cannot meet the application requirement, and the power conversion units that can access the power supply loop can be first controlled to access the power supply loop, and then the power conversion units in the power supply circuit (i.e., target power conversion units) are allocated power, and the target power conversion units are controlled according to the allocated power to meet the application requirement.

[0069] In the embodiment, the power allocated to the target power conversion units can be calculated according to the quantity of power conversion units in the power supply loop after the power conversion units access the power supply loop and the current energy supply requirement, and the target power conversion units are controlled to make the output power of the target power conversion units reach the allocated power.

[0070] Specifically, the power allocated to the target power conversion units can be calculated by P f = P 总 / m 总 . In the formula, P f represents the power allocated to each target power conversion unit, P 总 is the total demand power in the current power supply loop, and m 总 is the total quantity of target power conversion units in the current power supply loop.

[0071] In the embodiment, if the first quantity is zero, it indicates that there are no power conversion units that can access the power supply loop in the power supply circuit, and the output power of the target power conversion units can be directly adjusted according to the quantity of target power conversion units before and after the power conversion units are cut off to meet the application requirement.

[0072] Based on the scheme of the embodiment, the power conversion units in the power supply loop can be ensured to be operated at a rated capacity as much as possible, thereby reducing the control cost, ensuring the stable supply of energy, and meeting the application requirement.

[0073] In a possible implementation, the method for determining whether the power conversion unit is cut out in the power supply loop of the power supply circuit comprises the following steps:

[0074] Obtaining an electrical parameter of the power supply loop.

[0075] If the electrical parameter changes and the change amount of the electrical parameter reaches a preset change amount within a preset time, it is determined that the power conversion unit is cut out in the power supply loop.

[0076] In the embodiment, whether the power conversion unit is cut out can be determined directly according to the change of the electrical parameter in the power supply loop. The electrical parameter can be the output power, the output voltage, the output current or the like of the power supply loop. If the power conversion unit is a DC / DC unit, there is a DC bus in the power supply loop, and the electrical parameter can also be the bus voltage of the power supply loop. The change direction of the electrical parameter can be rising or falling, and the specific change direction can be determined according to the current direction in the power supply loop. For example, when the power conversion unit is a DC / DC unit, the method for determining whether the power conversion unit is cut out in the power supply loop of the power supply circuit can be detailed as follows:

[0077] Obtaining the bus voltage and the current direction of the power supply loop.

[0078] If the bus voltage decreases and the voltage value of the decreased bus voltage reaches a first preset value when the current direction is a discharging direction, it is determined that the power conversion unit is cut out in the power supply loop.

[0079] If the bus voltage increases and the voltage value of the increased bus voltage reaches a second preset value when the current direction is a charging direction, it is determined that the power conversion unit is cut out in the power supply loop.

[0080] In the embodiment, the first preset value and the second preset value can be the same. Specifically, the first preset value and the second preset value can be determined according to the number of current target power conversion units. For example, the first preset value and the second preset value can be determined by U0=U dc / N 总 Calculating the first preset value and the second preset value, wherein U0 is the first preset value and the second preset value, N 总 is the number of current target power conversion units, and U dc is the value of the bus voltage before the change (i.e., the bus voltage value before the bus voltage decreases or increases).

[0081] In a possible implementation, the method for detecting whether the power conversion unit is cut out in the power supply loop of the power supply circuit comprises the following steps:

[0082] Obtaining the online state of the power conversion unit from the controller of the power conversion unit.

[0083] According to the on-line state of the power conversion unit, it is determined whether the power conversion unit is cut out in the power supply loop.

[0084] In the embodiment, considering that there is sometimes no DC bus in the power supply loop (for example, when the power conversion unit is an energy storage converter, there is no DC bus in the power supply loop) and it is sometimes inconvenient to obtain the electrical parameters of the power supply loop (for example, when the execution subject is not directly connected with each power conversion unit, it is inconvenient to obtain the electrical parameters of the power supply loop), at this time, it can be determined through the communication between the execution subject and the controller of the power conversion unit whether the cut-out of the battery cluster exists in the power supply loop. That is, the on-line state detection result of the power conversion unit can be obtained from the controller of the power conversion unit, and according to the detection result, it is determined whether the power conversion unit is cut out in the power supply loop.

[0085] In a possible implementation, each power supply module further includes a battery cluster, the power conversion unit is connected with the battery cluster in one-to-one correspondence, and the power conversion unit is a bidirectional power conversion unit. On this basis, the output power of the target power conversion unit is controlled and adjusted according to the number of target power conversion units before and after the cut-out of the power conversion unit, including:

[0086] The output power of the target power conversion unit is lifted according to the number of target power conversion units before and after the cut-out of the power conversion unit.

[0087] In the embodiment, if the cut-out of the power conversion unit exists in the power supply loop, in order to ensure that the power supply loop can bear the power supply demand of the load or the charging demand of the battery cluster, the output power of the target power conversion unit can be lifted to avoid the impact on energy supply.

[0088] In the embodiment, when the output power of the power conversion unit is controlled and lifted, it is necessary to ensure that the output power of the power conversion unit after being lifted is not greater than the maximum power. The maximum power of the power conversion unit=k* rated power of the power conversion unit, and k is a preset value.

[0089] In a possible implementation, the output power of the target power conversion unit is controlled and adjusted according to the number of target power conversion units before and after the cut-out of the power conversion unit, including:

[0090] The target power is determined through P1*N1=P2*N2. P1 is the output power of the target power conversion unit before the cut-out of the power conversion unit, N1 is the number of target power conversion units before the cut-out of the power conversion unit, P2 is the target power, and N2 is the number of target power conversion units after the cut-out of the power conversion unit.

[0091] The output power of the target power conversion unit is controlled and adjusted to the target power.

[0092] In the embodiment, after the power conversion unit is cut off, the adjustment of the output power of the target power conversion unit can be performed according to the change in the number of target power conversion units.

[0093] In a possible implementation, each power supply module further includes a battery cluster, and the power conversion unit is connected to the battery cluster in one-to-one correspondence, and on this basis, the foregoing control method further includes:

[0094] obtaining the temperature of the battery cluster.

[0095] controlling the output power of the target power conversion unit to be reduced when the temperature of the battery cluster reaches a preset temperature.

[0096] In the embodiment, in order to prevent the overheating of the battery cluster from affecting the performance of the battery cluster, the temperature of the battery cluster is detected, and the output power of the target power conversion unit is controlled to be reduced when the temperature of the battery cluster is too high, so as to avoid the overheating of the battery cluster and ensure the service life of the battery cluster.

[0097] In a possible implementation, each power supply module further includes a battery cluster, and the power conversion unit is connected to the battery cluster in one-to-one correspondence, and if the target power is greater than the current output power of the target power conversion unit, before the output power of the target power conversion unit is controlled to be adjusted to the target power, the foregoing control method further includes:

[0098] predicting the temperature of the battery cluster in the power supply loop after a target process. The target process is a process of adjusting the output power of the target power conversion unit to the target power.

[0099] determining whether to perform the amplitude limiting processing on the target power according to the predicted temperature of the battery cluster.

[0100] In the embodiment, if the target power is greater than the current output power of the target power conversion unit, it indicates that the output power of the target power conversion unit needs to be controlled to be lifted. At this time, it is considered that:

[0101] The lifting of the output power of the target power conversion unit will cause the temperature of the battery cluster to rise to a certain extent, and when the temperature of the battery cluster rises, the output power of the target power conversion unit also needs to be controlled to be reduced in order to avoid the overheating of the battery cluster, that is, it may be necessary to first lift the output power and then reduce the output power, and such a control mode is obviously more complicated and more wasteful of control cost.

[0102] Therefore, the embodiment of the present application proposes a solution, that is, firstly, the temperature of the battery cluster is predicted, and it is predicted that after the output power of the target power conversion unit is lifted to the target power, what temperature of the battery cluster is. On this basis, whether the target power needs to be limited can be determined according to the predicted temperature of the battery cluster. Specifically, if the predicted temperature of the battery cluster is relatively low, the target power does not need to be limited. If the predicted temperature of the battery cluster is relatively high, the target power is directly limited, so as to avoid the power being reduced due to the temperature of the battery cluster after the power is lifted, thereby reducing the control cost.

[0103] In the embodiment, the change curve between the output power of the target power conversion unit and the temperature of the battery cluster can be calibrated in advance, and the change curve is used to indicate the change of the temperature of the battery cluster with the output power of the target power conversion unit. On this basis, after the target power is determined, the temperature of the battery cluster after the target process can be determined according to the target power and the pre-calibrated change curve.

[0104] In a possible implementation, whether the target power needs to be limited is determined according to the predicted temperature of the battery cluster, comprising:

[0105] When the predicted temperature of the battery cluster is less than the preset temperature, the target power is not limited.

[0106] When the predicted temperature of the battery cluster is greater than or equal to the preset temperature, the output power of the target power conversion unit when the temperature of the battery cluster reaches the preset temperature is calculated, and the limited power is obtained. The target power is limited based on the limited power.

[0107] In the embodiment, if the predicted temperature of the battery cluster is relatively low, it indicates that the lifting of the output power of the target power conversion unit will not cause the battery cluster to overheat, and at this time, the target power does not need to be limited. If the predicted temperature of the battery cluster is relatively high, it indicates that the lifting of the output power of the target power conversion unit may cause the battery cluster to overheat, and at this time, the target power can be limited.

[0108] Specifically, the output power of the target power conversion unit when the temperature of the battery cluster reaches the preset temperature can be determined according to the change curve between the output power of the target power conversion unit and the temperature of the battery cluster, and the output power of the target power conversion unit when the temperature of the battery cluster reaches the preset temperature is determined as the limited power.

[0109] The target power is replaced by the limited power.

[0110] The target power is replaced by the limited power.

[0111] In a possible implementation, the foregoing control method further comprises:

[0112] The voltage, current and temperature of the energy source connected to the power conversion unit are acquired, and whether the energy source connected to the power conversion unit is faulty is determined according to the voltage, current and temperature.

[0113] When it is determined that the energy source connected to the power conversion unit is faulty, the power conversion unit is controlled to be pulsed off and the contactor in the power conversion unit is controlled to be disconnected.

[0114] In the embodiment, the voltage, current and temperature of the energy source connected to the power conversion unit can be acquired, and whether the energy source connected to the power conversion unit is faulty is determined according to the voltage, current and temperature. When it is determined that the energy source connected to the power conversion unit is faulty, the power conversion unit can be controlled to be pulsed off and the contactor in the power conversion unit is controlled to be disconnected.

[0115] Specifically, the control method of the power conversion unit provided by each embodiment of the present application can be effectively applied to a power supply system comprising an energy storage container. As shown in Figure 2 , the energy storage container can comprise a plurality of energy storage converters and a plurality of battery clusters, and the energy storage converters are connected to the battery clusters one by one (at this time, the energy storage converter is the power conversion unit described in the embodiments of the present application). As shown in Figure 3 , the energy storage container can also comprise a plurality of power conversion units and a plurality of DC / DC units, and the power conversion units and the DC / DC units are connected one by one (at this time, the DC / DC unit is the power conversion unit described in the embodiments of the present application), and every x DC / DC unit is connected to an external energy storage converter (x is a preset value). Of course, the embodiments of the present application can also be effectively applied to a power supply system composed of modular UPS or modular charger. That is, regardless of the specific structure of the power supply system, the control method of the power conversion unit provided by the embodiments of the present application can guarantee the effective supply of energy when the number of power conversion units connected changes.

[0116] Please refer to Figure 4In another aspect of the present application, a control device 200 of a power conversion unit is also provided, which comprises one or more processors 201, one or more input devices 202, one or more output devices 203, and one or more memories 204. The processor 201, the input device 202, the output device 203, and the memory 204 can communicate with each other through a communication bus 205. The memory 204 is configured to store a computer program, which comprises program instructions. The processor 201 is configured to execute the program instructions stored in the memory 204. In some embodiments, the processor 201 can be a central processing unit (CPU). The processor can also be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like. The general-purpose processor can be a microprocessor or any conventional processor. The input device 202 can include a touchpad, a fingerprint collection sensor (for collecting fingerprint information and direction information of a fingerprint of a user), a microphone, or the like. The output device 203 can include a display (e.g., an LCD), a speaker, or the like. The memory 204 can include a read-only memory and a random access memory, and provide instructions and data for the processor 201. A portion of the memory 204 can also include a non-volatile random access memory. For example, the memory 204 can also store device type information. In some embodiments, the processor 201, the input device 202, and the output device 203 described in the present application can implement the methods described in the first and second embodiments of the control method of the power conversion unit.

[0117] In another aspect of the present application, a power supply system is also provided, which comprises:

[0118] The control device of the power conversion unit and the power supply circuit described above.

[0119] The above merely describes specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A control method of a power conversion unit, characterized by, The control method is applied to a power supply circuit including a plurality of power supply modules, each of which includes a power conversion unit, and is used to control each power conversion unit. The control method includes: determining whether there is a power conversion unit cutout in a power supply loop of the power supply circuit; if it is determined that there is a power conversion unit cutout in the power supply loop, controlling the power conversion units in the power supply circuit that can access the power supply loop to access the power supply loop, and / or adjusting the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout; wherein the target power conversion units refer to the power conversion units in the power supply loop.

2. The control method of a power conversion unit according to claim 1, characterized by, controlling the power conversion units in the power supply circuit that can access the power supply loop to access the power supply loop, and / or adjusting the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout, includes: obtaining the number of power conversion units in the power supply circuit that can access the power supply loop to obtain a first number; if the first number is greater than or equal to a second number, controlling the second number of power conversion units to access the power supply loop; the second number is the number of power conversion units cut out in the power supply loop; if the first number is less than the second number and the first number is not zero, controlling the first number of power conversion units to access the power supply loop, and distributing power to the target power conversion units according to the number of power conversion units in the power supply loop after the power conversion units access the power supply loop, and controlling the target power conversion units according to the distributed power; if the first number is zero, adjusting the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout.

3. The control method of a power conversion unit according to claim 1, characterized by, The determination of whether there is a power conversion unit cutout in the power supply loop of the power supply circuit includes: obtaining an electrical parameter of the power supply loop; if the electrical parameter changes and the change amount of the electrical parameter reaches a preset change amount within a preset time, it is determined that there is a power conversion unit cutout in the power supply loop.

4. The control method of a power conversion unit according to claim 1, wherein The determination of whether there is a power conversion unit cutout in the power supply loop of the power supply circuit includes: obtaining the online state of the power conversion unit from the controller of the power conversion unit; determining whether there is a power conversion unit cutout in the power supply loop according to the online state of the power conversion unit.

5. The control method of a power conversion unit according to claim 2, wherein Each power supply module further includes a battery cluster, and the power conversion unit is connected to the battery cluster one by one. Adjusting the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout includes: adjusting the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout.

6. The control method of a power conversion unit according to claim 2, wherein The adjustment of the output power of the target power conversion units according to the number of target power conversion units before and after the power conversion unit cutout includes: determining the target power by P1*N1=P2*N2, wherein P1 is the output power of the target power conversion unit before the power conversion unit is cut off, N1 is the number of the target power conversion unit before the power conversion unit is cut off, P2 is the target power, and N2 is the number of the target power conversion unit after the power conversion unit is cut off; controlling the output power of the target power conversion unit to adjust to the target power.

7. The control method of a power conversion unit according to claim 6, wherein Each power supply module further comprises a battery cluster, and the power conversion unit is connected to the battery cluster one by one; if the target power is greater than the current output power of the target power conversion unit, before the output power of the target power conversion unit is controlled to adjust to the target power, the control method further comprises: predicting the temperature of the battery cluster in the target process in the power supply loop; wherein the target process is the process of adjusting the output power of the target power conversion unit to the target power; determining whether to perform the amplitude limiting processing on the target power according to the predicted temperature of the battery cluster.

8. The control method of a power conversion unit according to claim 7, wherein The determination whether to perform the amplitude limiting processing on the target power according to the predicted temperature of the battery cluster comprises: when the predicted temperature of the battery cluster is less than a preset temperature, not performing the amplitude limiting processing on the target power; when the predicted temperature of the battery cluster is greater than or equal to the preset temperature, calculating the output power of the target power conversion unit when the temperature of the battery cluster reaches the preset temperature to obtain the amplitude limiting power; and performing the amplitude limiting processing on the target power based on the amplitude limiting power.

9. A control device of a power conversion unit, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the steps of the method of any one of claims 1 to 8.

10. A power supply system characterized by comprising: comprises: The power conversion unit control device of claim 9 and the power supply circuit of claim 1.

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