Method for switching power supply of fast switching device and fast switching device

Abstract

The invention provides a power supply switching method of a fast switching device and the fast switching device, and the method comprises the steps: collecting an instantaneous value of a target voltage on a bus according to a preset period after the disconnection of a main power supply is recognized; acquiring a real-time peak value and a real-time phase angle of a target voltage on the bus according to a formula under the condition that the angular frequency of the voltage is regarded as unchanged in a short time; and according to the real-time peak value and the real-time phase angle, determining whether to execute an operation of connecting the bus to a backup power supply.

Description

Technical Field

[0001] The invention relates to the field of power systems, and in particular to a method for switching power supplies using a quick-cut device and a quick-cut device. Background Art

[0002] In many large-scale industries, in order to ensure the reliability and continuity of power supply, the power supply system generally has two independent power supplies, and the electrical equipment is mainly motors. The two power supplies can serve as backup for each other, or one can work and the other can be backup. In the event of a power failure, the load needs to be safely and quickly switched to the other power supply to ensure the continuity of production.

[0003] In the prior art, a quick-cut device is generally used to trigger the switching operation between two power sources, that is, to switch the power supply to the backup power supply. As an example, the power system generally includes a quick-cut device and at least two power sources. Figure 1 The figure shows the situation of two power supplies. The power supply currently working can be used as the main power supply, and the other power supply can be used as the backup power supply. Figure 1 As shown, the main power supply P1 is connected to the busbar through an incoming line, and the backup power supply P2 is also connected to the busbar through an incoming line. The three phases included in the incoming line are phase A, phase B and phase C, which are respectively connected to the corresponding three phases of the busbar BB. Each load is connected to the busbar BB through an outgoing line. In other words, the incoming line, busbar and outgoing line on phase A are connected together, and similarly, the incoming line, busbar and outgoing line on phase B and phase C are also connected together. The incoming line of the main power supply P1 has a switch CB1, through which the connection between the main power supply P1 and the busbar BB can be disconnected, and the incoming line of the backup power supply P2 has a switch CB2, through which the connection between the backup power supply P2 and the busbar BB can be disconnected.

[0004] When a fault occurs in the power system, the relay protection device will start, disconnect the first main power supply P1 that is currently supplying power, and the fast-cut device 101 will quickly switch the bus BB to the backup power supply P2, so that the backup power supply P2 supplies power to the bus BB. There are many ways to implement switching, among which the most ideal fast switching method is that the frequency difference between the bus and the backup power supply is less than the fast switching frequency difference, and the phase angle difference between the bus and the backup power supply is less than the fast switching phase angle difference. When the fast switching is unsuccessful, the synchronous capture switching is the switching method second only to the fast switching. The condition for realizing the synchronous capture switching is that when the backup power supply is closed, the phase angle difference between the bus and the backup power supply is less than the synchronous capture switching phase angle difference. It can be seen that both of the fastest switching methods require the acquisition of the phase angle difference. In order to obtain the phase angle difference, the phase angle on the bus needs to be acquired in real time to be combined with the phase angle of the backup power supply to calculate whether it meets the switching conditions.

[0005] In the prior art, in order to calculate the phase angle of the bus, it is necessary to sample the voltage of the bus in real time to obtain the instantaneous value of the voltage, and calculate the phase angle through Fourier transform based on the instantaneous value of the voltage. This method requires a large number of samples. For example, if a 50Hz power system is sampled once every 1 millisecond, it will take at least 20 milliseconds to calculate the phase angle of the bus. This calculation method takes a long time and is likely to miss the closing opportunity of the fast switching method or synchronous capture switching. Summary of the invention

[0006] In view of this, the present invention proposes a method for switching power supply by a fast-cut device, wherein the fast-cut device is located in a power system, wherein the power system includes a main power supply and a backup power supply, wherein the fast-cut device can trigger switching between the two power supplies, wherein the main power supply and the backup power supply are both connected to a bus, and wherein the method comprises:

[0007] After identifying that the main power supply is disconnected, collecting an instantaneous value of a target voltage on the bus according to a preset cycle;

[0008] The real-time peak value and real-time phase angle of the target voltage on the bus are obtained according to the following formula:

[0009] A=(X′X) -1 X′V

[0010] in,

[0011]

[0012]

[0013] M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i;

[0014] Whether to perform an operation of connecting the busbar to a backup power source is determined according to the real-time peak value and the real-time phase angle.

[0015] According to the method described above, optionally, the value of k is 4-5.

[0016] According to the method as described above, optionally, collecting the instantaneous value of the target voltage on the bus according to a preset cycle includes: collecting the instantaneous value of the target voltage corresponding to a target of the bus at the same time according to a preset cycle, the target phase being one of the three phases of the bus;

[0017] Obtaining the real-time peak value and the real-time phase angle of the target voltage on the bus according to the following formula includes: obtaining the real-time peak value and the real-time phase angle of the target voltage of the target phase according to the following formula.

[0018] According to the method as described above, optionally, collecting the instantaneous value of the target voltage on the bus according to a preset cycle includes: collecting the instantaneous value of each corresponding target voltage of the bus at the same time according to a preset cycle;

[0019] Obtaining the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula includes: obtaining the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula;

[0020] Determining whether to connect the bus to a backup power supply based on the real-time peak value and the real-time phase angle includes: taking the average value of the real-time peak values ​​of each phase as the final real-time peak value, and taking the average value of the real-time phase angles of each phase as the final real-time phase angle; determining whether to connect the bus to a backup power supply based on the final real-time peak value and the final real-time phase angle.

[0021] The present invention also provides a quick-cut device, which is located in a power system, the power system includes a main power supply and a backup power supply, the quick-cut device can trigger switching between the two power supplies, the main power supply and the backup power supply are both connected to a bus, and the quick-cut device includes:

[0022] a sampling unit, which is used to collect the instantaneous value of the target electricity on the bus according to a preset period;

[0023] An acquisition unit is used to acquire the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula:

[0024] A=(X′X) -1 X′V

[0025] in,

[0026]

[0027]

[0028] M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i;

[0029] A determination unit is used to determine whether to perform an operation of connecting the busbar to a backup power supply according to the real-time peak value and the real-time phase angle after identifying that the main power supply is disconnected.

[0030] According to the quick-cut device as described above, optionally, the value of k is 4-5.

[0031] According to the fast switching device as described above, optionally, the sampling unit is specifically used to: simultaneously collect the instantaneous value of a target voltage corresponding to a target of the bus according to a preset cycle, and the target phase is one of the three phases of the bus;

[0032] The acquisition unit is specifically used to acquire the real-time peak value and the real-time phase angle of the target voltage of the target phase according to the following formula.

[0033] According to the fast switching device as described above, optionally, the sampling unit is specifically used to: simultaneously collect the instantaneous value of each corresponding target voltage of the bus according to a preset cycle;

[0034] The acquisition unit is specifically used to: acquire the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula;

[0035] The determination unit is specifically used to: take the average value of the real-time peak values ​​of each phase as the final real-time peak value, and take the average value of the real-time phase angles of each phase as the final real-time phase angle; and determine whether to connect the bus to a backup power supply based on the final real-time peak value and the final real-time phase angle.

[0036] The present invention further provides a quick-cut device, comprising:

[0037] at least one memory for storing instructions;

[0038] At least one processor is used to execute the method for switching power supply by a fast-cut device according to any one of the above items according to the instructions stored in the memory.

[0039] The present invention further provides a readable storage medium, wherein the readable storage medium stores machine-readable instructions. When the machine-readable instructions are executed by a machine, the machine executes the method for switching power supply by a fast-cut device according to any one of the above items.

[0040] It can be seen from the above scheme that by considering the angular frequency on the bus in a short period of time as constant and using the above formula to calculate the real-time peak value and real-time phase angle of the target voltage of the bus with fewer sampling points, the timing of closing the backup power supply can be determined more quickly, which is particularly suitable for fast switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the above and other features and advantages of the present invention will be more apparent to those skilled in the art. In the accompanying drawings:

[0042] Figure 1 The figure is a flow chart of a method for switching power supply by a fast switching device according to an embodiment of the present invention.

[0043] Figure 2A The figure is a flow chart of a method for switching power supply using a fast switching device according to another embodiment of the present invention.

[0044] Figure 2B It is a schematic diagram of a curve of a real-time phase angle of voltage and a curve of an actual phase angle obtained by a method for switching power supply using a fast-cutting device according to another embodiment of the present invention.

[0045] Figure 2C It is a schematic diagram of a curve of a real-time peak value of voltage and a curve of a real amplitude obtained by a method for switching power supply using a fast-cut device according to another embodiment of the present invention.

[0046] Figure 3A The figure is a flow chart of a method for switching power supply using a fast switching device according to another embodiment of the present invention.

[0047] Figure 3B The diagram is a schematic diagram of a curve of a real-time phase angle of voltage and a curve of an actual phase angle obtained by using a method for switching power supply using a fast-cut device according to another embodiment of the present invention.

[0048] Figure 3C The diagram is a schematic diagram of a curve of a real-time peak value of voltage and a curve of a real amplitude obtained by a method for switching power supply using a fast-cut device according to another embodiment of the present invention.

[0049] Figure 4 Schematic diagram of the structure of a quick-cut device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail with reference to the following embodiments. Nouns and pronouns related to people in this patent application are not limited to specific genders.

[0051] For the power system, the voltage is AC voltage, so the instantaneous value of the voltage changes in real time. The fast switching device calculates the phase angle by periodically sampling the voltage.

[0052] When the main power supply is disconnected, the bus loses power supply, the amplitude of the voltage on it gradually decreases, and the frequency of the voltage also gradually decreases, but the frequency changes slowly, and the angular frequency of the voltage ω = 2πf, where f is the frequency of the voltage. Therefore, within a short period of time, such as 4-5 milliseconds, it can be considered that the angular frequency of the voltage remains unchanged.

[0053] Based on this, the inventor of the present invention proposes a method for switching power supply using a fast switching device.

[0054] Embodiment 1

[0055] This embodiment provides a method for switching power supply by a fast-cut device, the execution subject of which is a fast-cut device. The fast-cut device is located in a power system, the power system includes a main power supply and a backup power supply, the fast-cut device can trigger switching between the two power supplies, the main power supply and the backup power supply are both connected to a bus,

[0056] like Figure 1 FIG. 1 is a flow chart of a method for switching power supplies according to this embodiment. The method for switching power supplies includes:

[0057] Step 101 : after identifying that the main power supply is disconnected, collecting the instantaneous value of the target voltage on the bus according to a preset cycle.

[0058] The fast switching device monitors the voltage on the bus in real time and collects the instantaneous value of the voltage according to a preset period. The preset period in this step is the sampling period. The specific collection period can be set according to actual needs, for example, once every 1 millisecond.

[0059] In this embodiment, after identifying that the main power supply is disconnected, the quick-cut device continues to monitor the voltage on the bus in real time, and calculates the real-time peak value and real-time phase angle of the voltage based on the collected voltage sampling values. In this example, the voltage on the bus sampled after identifying that the main power supply is disconnected is called the target voltage. Whether the main power supply is disconnected can be identified by monitoring the voltage of the bus, the current of the bus and / or the frequency of the bus, and the specific identification method can be any existing technology, which will not be repeated here.

[0060] The quick-cut device can collect the voltage of any phase on the bus as the target voltage. The collected voltage is the instantaneous value of the target voltage of the bus on that phase. Of course, the voltage on the three phases can also be collected and processed as the target voltage. The specific selection can be made according to actual needs and will not be repeated here.

[0061] Step 102: Obtain the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula.

[0062] A=(X′X) -1 X′V

[0063] in,

[0064]

[0065]

[0066] M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i.

[0067] It is conceivable that, since the target voltage changes gradually, its peak value is also changing all the time, so it is necessary to determine the real-time peak value of the voltage based on the sampling value. Here, k is, for example, 4-5, and its sampling frequency is, for example, once every 1 millisecond. When k is 4-5, the sampling value is 4-5, so the sampling window experienced is 4 to 5 milliseconds. This time is very short, and the change in the angular frequency of the bus voltage can be ignored. Specifically, the angular frequency of the bus voltage ω=2πf, where f is the real-time frequency of the bus voltage. Since the main power supply is disconnected, the bus loses power supply, so the voltage thereon gradually decreases, and the frequency of the voltage also gradually decreases. In this embodiment, after identifying that the main power supply is disconnected, the calculation of M and The sampling values ​​used are relatively small and the sampling window is relatively small, so the change in the voltage frequency can be ignored, and accordingly, the change in the angular frequency can also be ignored. In this embodiment, the angular frequency of the target voltage can be calculated using the rated frequency, that is, f=50Hz, and the 50hz is the rated frequency of the power grid. Of course, the angular frequency of the target voltage can also be calculated using the existing method, and the details will not be repeated.

[0068] The instantaneous value of voltage has the following relationship with the real-time peak value, real-time phase angle and angular frequency of voltage:

[0069]

[0070] Where v(t) represents the instantaneous value of the voltage sampled at time t, ω represents the angular frequency of the voltage, represents the phase angle of the voltage, M represents the peak value of the voltage, t represents the current moment, and the time point when sampling starts is time 0. t represents the current moment, and the time point when sampling starts is the starting point of the sampling window for calculating the real-time peak value and real-time phase angle.

[0071] Therefore, the instantaneous value of the sampling voltage can be expressed by the following formula:

[0072]

[0073]

[0074] …

[0075]

[0076] …

[0077]

[0078] Among them, t i It represents the time corresponding to the i-th sampling point, for example, sampling is performed once in 1 millisecond, and the time when the target voltage starts to be sampled is 0 milliseconds, t1 represents 1 millisecond, and t2 represents 2 milliseconds.

[0079] Thus, the above formula can be rewritten as:

[0080]

[0081] That is, V = XA,

[0082] in,

[0083]

[0084]

[0085] Thus, A=(X′X) -1 X′V.

[0086] Step 103: Determine whether to connect the bus to the backup power source according to the real-time peak value and the real-time phase angle.

[0087] The quick-cut device can further determine the closing mode and closing time of the backup power supply based on the real-time peak value and real-time phase angle obtained. For example, the real-time peak value cannot be lower than a certain value, and the difference between the real-time phase angle and the phase angle of the backup power supply needs to meet the switching conditions, which can be determined according to actual needs and will not be repeated here.

[0088] In addition, the real-time peak value of the target voltage can also be used for other judgments, such as judging whether the busbar loses voltage, etc.

[0089] According to the present invention, by considering the angular frequency on the bus in a short period of time as constant, and using the above formula, the real-time peak value and real-time phase angle of the target voltage of the bus can be calculated using fewer sampling points. This can quickly determine the timing of closing the backup power supply, which is particularly suitable for fast switching methods.

[0090] Embodiment 2

[0091] This embodiment further supplements the method for switching power supplies in the first embodiment.

[0092] like Figure 2A FIG. 1 is a flow chart of a method for switching power supply by a fast switching device according to this embodiment. The method for switching power supply by a fast switching device includes:

[0093] Step 201 : after identifying that the main power supply is disconnected, the instantaneous value of a target voltage corresponding to a target of the bus is simultaneously collected according to a preset cycle.

[0094] For a power system, there are generally three phases, namely phase A, phase B and phase C. The target phase in this embodiment can be any one of the three phases, or a phase that is determined to be free of faults by other means. The specific selection can be based on actual needs and will not be repeated here.

[0095] Step 202: Obtain the real-time peak value and real-time phase angle of a target voltage of a target phase of the bus according to the following formula:

[0096] A=(X′X) -1 X′V

[0097] in,

[0098]

[0099]

[0100] M is the real-time peak value of the target voltage of the target phase, is the real-time phase angle of the target voltage of the target phase, ω is the angular frequency of the target voltage of the target phase, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage of the target phase corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i.

[0101] This step is specifically the same as step 102 and will not be described again here.

[0102] Step 203: Determine whether to connect the bus to the backup power source according to the real-time peak value and the real-time phase angle of the target phase.

[0103] This step is specifically the same as step 103 and will not be described again here.

[0104] like Figure 2B As shown in FIG. 1 , the curve N1 of the real-time peak value of the target voltage obtained by the method of switching power supply using the fast-cut device of this embodiment and the curve N2 of the real amplitude are shown in FIG. As can be seen from the figure, the two curves almost overlap. Figure 2C As shown, the schematic diagram is a schematic diagram of the curve R1 of the real-time phase angle of the target voltage obtained by the method of switching the power supply using the fast-cut device of this embodiment and the curve R2 of the real phase angle. It can be seen from the figure that the two curves almost overlap. That is, it has been verified that even if the angular frequency of the target voltage is inaccurate, for example, when the rated angular frequency is fixed, the real-time peak value and real-time phase angle obtained by the method of this embodiment are also more consistent with the real value. For details, please refer to Figure 2B and Figure 2C The rated angular frequency here can be obtained by adopting the rated frequency of the power grid, and the rated frequency is, for example, 50 Hz.

[0105] According to this embodiment, by using one of the three phases of the bus as the target phase and determining the real-time peak value and real-time phase angle of the bus voltage through the target phase, the amount of calculation is small and the implementation is relatively convenient.

[0106] Embodiment 3

[0107] This embodiment further supplements the method for switching power supplies in the first embodiment.

[0108] like Figure 3A FIG. 1 is a flow chart of a method for switching power supply by a fast switching device according to this embodiment. The method for switching power supply by a fast switching device includes:

[0109] Step 301 : after identifying that the main power supply is disconnected, the instantaneous value of each corresponding target voltage of the bus is simultaneously collected according to a preset cycle.

[0110] Generally, there are three phases in the power system, namely, phase A, phase B and phase C. In this embodiment, the instantaneous value of the voltage on each phase of the bus can be collected simultaneously, that is, the voltage of each phase is the target voltage.

[0111] Step 302: Obtain the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula.

[0112] A=(X′X) -1 X′V

[0113] in,

[0114]

[0115]

[0116] M is the real-time peak value, is the real-time phase angle, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i.

[0117] The final M obtained by phase A can be represented by M(A), the final M obtained by phase B can be represented by M(B), and the final M obtained by phase C can be represented by M(C). Can be used To show that the final value of phase B is Can be used To show that the final C phase Can be used To express.

[0118] Step 303: taking the average value of the real-time peak values ​​of each phase as the final real-time peak value, and taking the average value of the real-time phase angles of each phase as the final real-time phase angle.

[0119] That is, the final real-time peak value = [M(A)+M(B)+M(C)] / 3, the final

[0120] Step 304: Determine whether to connect the bus to the backup power source according to the final real-time peak value and the final real-time phase angle.

[0121] This step is consistent with the operation of step 103 and will not be described again here.

[0122] like Figure 3B As shown, it is a schematic diagram of the curve Q1 of the final real-time peak value of the voltage and the curve Q2 of the actual voltage amplitude obtained by the method of switching power supply using the fast switching device of this embodiment. Figure 3C , which is a schematic diagram of a curve P1 of the final real-time phase angle of the voltage obtained by the method of switching power supply using the fast-cut device of this embodiment and a curve P2 of the actual phase angle. Figure 3B and Figure 3CIt can be seen that the degree of conformity between P1 and P2 and the degree of conformity between Q1 and Q2 in this embodiment are better than those in the second embodiment. In this embodiment, the voltage of the three phases on the bus is sampled, and the real-time peak value and real-time phase angle of the final voltage on the bus are obtained based on the average value of the real-time peak value of the voltage obtained for each phase and the average value of the real-time phase angle. In this way, even if the angular frequency is inaccurate, the real-time peak value and real-time phase angle obtained by a single phase have fluctuation errors, and the errors of the three phases are symmetrical. The average value of the real-time peak value of the voltage and the average value of the real-time phase angle of the three phases can greatly reduce the impact of the change in angular frequency. Therefore, the real-time peak value and real-time phase obtained by the three-phase average value will offset each other, and still have high accuracy when the angular frequency is inaccurate.

[0123] Embodiment 4

[0124] This embodiment provides a quick-cut device, which is used in the method for switching power supplies of the quick-cut device of embodiment 1. The quick-cut device is located in a power system, which includes a main power supply and a backup power supply. The quick-cut device can trigger switching between the two power supplies, and both the main power supply and the backup power supply are connected to a bus.

[0125] like Figure 4 4 is a schematic diagram of the structure of the fast switching device according to this embodiment. The fast switching device includes a sampling unit 401 , an acquisition unit 402 and a determination unit 403 .

[0126] The sampling unit 401 is used to collect the instantaneous value of the target electricity on the bus according to a preset period;

[0127] The acquisition unit 402 is used to acquire the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula:

[0128] A=(X′X) -1 X′V

[0129] in,

[0130]

[0131]

[0132] M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i.

[0133] The adoption unit is specifically used to determine whether to execute the operation of connecting the busbar to the backup power supply according to the real-time peak value and the real-time phase angle after recognizing that the main power supply is disconnected.

[0134] As an exemplary illustration, the value of k is 4-5.

[0135] The working methods of each unit in this embodiment are the same as those in the previous embodiment and will not be described again here.

[0136] According to the present invention, the fast switching device regards the angular frequency on the bus in a short period of time as constant, and can calculate the real-time peak value and real-time phase angle of the target voltage of the bus with fewer sampling points through the above formula, so that the timing of closing the backup power supply can be determined more quickly, which is particularly suitable for fast switching mode.

[0137] Embodiment 5

[0138] This embodiment further supplements the quick-cut device of the fourth embodiment.

[0139] Example 1:

[0140] The adopting unit of the fast switching device is used to simultaneously collect the instantaneous value of a target voltage corresponding to a target of the bus according to a preset cycle, and the target phase is one of the three phases of the bus;

[0141] The acquisition unit 402 is used to acquire the real-time peak value and real-time phase angle of the target voltage of the target phase according to the following formula:

[0142] A=(X′X) -1 x′V

[0143] in,

[0144]

[0145]

[0146] In this way, by using one of the three phases of the bus as the target phase and determining the real-time peak value and real-time phase angle of the bus voltage through the target phase, the amount of calculation is small and the implementation is relatively convenient.

[0147] Example 2:

[0148] The sampling unit 401 of the fast switching device is specifically used to simultaneously collect the instantaneous value of each corresponding target voltage of the bus according to a preset cycle.

[0149] The acquisition unit 402 is used to acquire the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula:

[0150] A=(X′X)-1 X′V

[0151] in,

[0152]

[0153]

[0154] The final M obtained by phase A can be represented by M(A), the final M obtained by phase B can be represented by M(B), and the final M obtained by phase C can be represented by M(C). Can be used To show that the final value of phase B is Can be used To show that the final C phase Can be used To express.

[0155] The determination unit 403 is specifically used to: take the average value of the real-time peak values ​​of each phase as the final real-time peak value, and take the average value of the real-time phase angles of each phase as the final real-time phase angle; and determine whether to connect the bus to the backup power supply based on the final real-time peak value and the final real-time phase angle.

[0156] That is, the final real-time peak value = [M(A)+M(B)+M(C)] / 3, the final

[0157] The working methods of each unit in this embodiment are the same as those in the previous embodiment and will not be described again here.

[0158] In this embodiment, the voltage of the three phases on the bus is sampled, and the real-time peak value and real-time phase angle of the final voltage on the bus are obtained based on the average value of the real-time peak value of the voltage obtained for each phase and the average value of the real-time phase angle. In this way, even if the angular frequency is inaccurate, the real-time peak value and real-time phase angle obtained by using a single phase have fluctuation errors, while the errors of the three phases are symmetrical. The average value of the real-time peak value of the voltage and the average value of the real-time phase angle of the three phases can greatly reduce the impact of the angular frequency change. Therefore, the real-time peak value and real-time phase obtained by the three-phase average value will offset each other, and still have high accuracy when the angular frequency is inaccurate.

[0159] The present invention also provides a fast switching device, comprising at least one memory and at least one processor. The memory is used to store instructions. The processor is used to execute the method for switching power supply of the fast switching device described in any of the above embodiments according to the instructions stored in the memory.

[0160] An embodiment of the present invention further provides a readable storage medium in which machine-readable instructions are stored. When the machine-readable instructions are executed by a machine, the machine executes the method for switching power supply by a fast-cut device as described in any of the above embodiments.

[0161] The readable medium stores machine-readable instructions, which, when executed by the processor, cause the processor to execute any of the aforementioned methods. Specifically, a system or device equipped with a readable storage medium may be provided, on which a software program code implementing the functions of any of the above-mentioned embodiments is stored, and a computer or processor of the system or device reads and executes the machine-readable instructions stored in the readable storage medium.

[0162] In this case, the program code itself read from the machine-readable medium can realize the function of any one of the above-mentioned embodiments, and thus the machine-readable code and the machine-readable storage medium storing the machine-readable code constitute a part of the present invention.

[0163] Examples of readable storage media include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, the program code may be downloaded from a server computer or a cloud via a communication network.

[0164] Those skilled in the art should understand that the various embodiments disclosed above can be modified and altered in various ways without departing from the essence of the invention. Therefore, the protection scope of the present invention should be defined by the appended claims.

[0165] It should be noted that not all steps and units in the above-mentioned processes and system structure diagrams are necessary, and some steps or units can be ignored according to actual needs. The execution order of each step is not fixed and can be adjusted as needed. The device structure described in the above-mentioned embodiments can be a physical structure or a logical structure, that is, some units may be implemented by the same physical entity, or some units may be implemented by multiple physical entities, or some components in multiple independent devices may be implemented together.

[0166] In the above embodiments, the hardware unit can be realized by mechanical means or electrical means. For example, a hardware unit or a processor can include permanent dedicated circuits or logic (such as special processors, FPGA or ASIC) to complete the corresponding operation. The hardware unit or the processor can also include programmable logic or circuits (such as general-purpose processors or other programmable processors), which can be temporarily set by software to complete the corresponding operation. Concrete implementation (mechanical means or dedicated permanent circuits or temporarily set circuits) can be determined based on cost and time considerations.

[0167] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for switching power supply by a fast-cut device, wherein the fast-cut device is located in a power system, wherein the power system includes a main power supply and a backup power supply, wherein the fast-cut device can trigger switching between the two power supplies, wherein both the main power supply and the backup power supply are connected to a bus, and wherein the method comprises: After identifying that the main power supply is disconnected, collecting an instantaneous value of a target voltage on the bus according to a preset cycle; It is characterized in that the real-time peak value and real-time phase angle of the target voltage on the bus are obtained according to the following formula: A=(X′X) -1 X′V in, M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i; Whether to perform an operation of connecting the busbar to a backup power source is determined according to the real-time peak value and the real-time phase angle.

2. The method according to claim 1, characterized in that The value of k is 4-5.

3. The method according to claim 1 or 2, characterized in that: Collecting the instantaneous value of the target voltage on the bus according to a preset cycle includes: collecting the instantaneous value of the target voltage corresponding to a target of the bus at the same time according to a preset cycle, the target phase being one of the three phases of the bus; Obtaining the real-time peak value and the real-time phase angle of the target voltage on the bus according to the following formula includes: obtaining the real-time peak value and the real-time phase angle of the target voltage of the target phase according to the following formula.

4. The method according to claim 1 or 2, characterized in that: Collecting the instantaneous value of the target voltage on the bus according to a preset cycle includes: collecting the instantaneous value of each corresponding target voltage of the bus at the same time according to a preset cycle; Obtaining the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula includes: obtaining the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula; Determining whether to connect the bus to a backup power supply based on the real-time peak value and the real-time phase angle includes: taking the average value of the real-time peak values ​​of each phase as the final real-time peak value, and taking the average value of the real-time phase angles of each phase as the final real-time phase angle; determining whether to connect the bus to a backup power supply based on the final real-time peak value and the final real-time phase angle.

5. A quick-cut device, which is located in a power system, the power system includes a main power supply and a backup power supply, the quick-cut device can trigger switching between the two power supplies, the main power supply and the backup power supply are both connected to a bus, and the quick-cut device includes: a sampling unit, which is used to collect the instantaneous value of the target electricity on the bus according to a preset period; Characterized in that the quick-cut device also includes: An acquisition unit is used to acquire the real-time peak value and real-time phase angle of the target voltage on the bus according to the following formula: A=(X′X) -1 X′V in, M is the real-time peak value of the target voltage, is the real-time phase angle of the target voltage, ω is the angular frequency of the target voltage, t i is the time corresponding to the i-th sampling point, v i is the instantaneous value of the target voltage corresponding to the i-th sampling value, k and i are both positive integers and k is greater than or equal to i; A determination unit is used to determine whether to perform an operation of connecting the busbar to a backup power supply according to the real-time peak value and the real-time phase angle after identifying that the main power supply is disconnected.

6. The quick-cut device according to claim 6, characterized in that: The value of k is 4-5.

7. The quick-cut device according to claim 5 or 6, characterized in that: The sampling unit is specifically used to: simultaneously collect the instantaneous value of a target voltage corresponding to a target of the bus according to a preset cycle, and the target phase is one of the three phases of the bus; The acquisition unit is specifically used to acquire the real-time peak value and the real-time phase angle of the target voltage of the target phase according to the following formula.

8. The quick-cut device according to claim 5 or 6, characterized in that: The sampling unit is specifically used to: simultaneously collect the instantaneous value of each corresponding target voltage of the bus according to a preset period; The acquisition unit is specifically used to: acquire the real-time peak value and real-time phase angle of the target voltage of each phase on the bus according to the following formula; The determination unit is specifically used to: take the average value of the real-time peak values ​​of each phase as the final real-time peak value, and take the average value of the real-time phase angles of each phase as the final real-time phase angle; and determine whether to connect the bus to a backup power supply based on the final real-time peak value and the final real-time phase angle.

9. Quick-cut device, characterized in that: include: at least one memory for storing instructions; At least one processor, configured to execute the method for switching power supply by a fast-cutting device according to any one of claims 1 to 4 according to the instructions stored in the memory.

10. A readable storage medium, characterized in that: The readable storage medium stores machine-readable instructions. When the machine-readable instructions are executed by a machine, the machine executes the method for switching power supply with a fast-cut device according to any one of claims 1 to 4.

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