Black start method, device, electronic device, storage medium and program product

Abstract

The embodiments of the present application provide a black start method, device, electronic device, storage medium and program product, which relate to the field of power grid technology. The method includes: predicting the load of the power system, and obtaining the energy storage information of the energy storage unit; determining the initial output power corresponding to the energy storage conversion unit according to the load and the energy storage information; and controlling the energy storage conversion unit to supply power to the power system based on the initial output power, so that the output power of the energy storage conversion unit matches the load. During the black start process, the output power of the energy storage conversion unit is determined based on the predicted load and energy storage information of the power system, which can effectively reduce the probability of black start failure.

Description

Technical Field

[0001] The present application relates to the field of power grid technology, and in particular to a black start method, device, electronic device, storage medium and program product. Background Art

[0002] With the rapid development of distributed energy, distributed grid technology has gradually become an important means to solve the uneven distribution of energy and improve energy efficiency. However, during the operation of the grid, due to the randomness and intermittency of distributed power sources, the stability of the grid is prominent. After a power outage caused by a grid failure, how to quickly restore power supply becomes a key issue.

[0003] In the related art, the power supply of the power grid can be restored by a black start method, but the failure probability of the black start is high. Summary of the invention

[0004] The embodiments of the present application provide a black start method, device, electronic device, storage medium and program product, which can reduce the probability of black start failure.

[0005] In a first aspect, an embodiment of the present application provides a black start method, comprising:

[0006] Predict the load of the power system and obtain the energy storage information of the energy storage unit;

[0007] Determining an initial output power corresponding to an energy storage conversion unit according to the load and the energy storage information;

[0008] The target energy storage and conversion unit is controlled to supply power to the power consumption system based on the initial output power, so that the output power of the energy storage and conversion unit matches the load.

[0009] In some embodiments, controlling the target energy storage conversion unit to supply power to the power system based on the initial output power includes:

[0010] Within the target duration, controlling the target energy storage conversion unit to operate based on the initial output power, and collecting the current value and voltage value output by the energy storage conversion unit;

[0011] Determining actual output power according to the current value and the voltage value;

[0012] Based on the actual output power and the initial output power, the energy storage conversion unit is controlled to supply power to the power consumption system.

[0013] In some embodiments, controlling the energy storage conversion unit to supply power to the power system based on the actual output power and the initial output power includes:

[0014] Based on the actual output power and the initial output power, obtaining the electromotive force amplitude and output frequency of the energy storage conversion unit;

[0015] generating a power supply control signal of the energy storage conversion unit according to the electromotive force amplitude and the output frequency;

[0016] The energy storage and conversion unit is controlled to operate according to the power supply control signal, so that the energy storage and conversion unit outputs electric energy to the power consumption system according to the electromotive force amplitude and the output frequency.

[0017] In some embodiments, the collected current value and voltage value output by the energy storage conversion unit are three-phase AC current value and three-phase AC voltage value. Before determining the actual output power according to the current value and the voltage value, the method further includes:

[0018] Coordinate transformation is performed on the three-phase AC voltage value and the three-phase AC current value, and the three-phase AC voltage value and the three-phase AC current value are converted into two-phase DC voltage value and two-phase DC current value.

[0019] In some embodiments, generating a power supply control signal of the energy storage conversion unit according to the electromotive force amplitude and the output frequency includes:

[0020] According to the electromotive force amplitude, the output frequency, and the two-phase DC voltage value, a control current of the energy storage conversion unit is obtained; the control current is used to characterize that the energy storage conversion unit outputs current with the control current;

[0021] According to the control current of the energy storage conversion unit and the output frequency, a control voltage of the energy storage conversion unit is obtained; the control voltage is used to characterize the output voltage of the target energy storage conversion unit;

[0022] Converting the control voltage of the energy storage converter unit into a three-phase AC control voltage;

[0023] A power supply control signal of the energy storage conversion unit is generated according to the three-phase AC control voltage; the power supply control signal is used to instruct the energy storage conversion unit to output electric energy to the power consumption system according to the control voltage and the control current.

[0024] In some embodiments, predicting the load of the power system includes:

[0025] Obtaining the historical load of the power system;

[0026] Sampling the historical load to generate a time series based on the historical load;

[0027] Fitting the time series of the historical load to generate a load trend of the power system;

[0028] The load of the power system is predicted according to the load trend.

[0029] In some embodiments, there are multiple energy storage conversion units, each of which is connected to at least one energy storage unit, and the method further includes:

[0030] Obtaining power information of energy storage units connected to each energy storage conversion unit;

[0031] Based on the power information and the predicted load of the power system, an energy storage conversion unit corresponding to an energy storage unit whose power value is greater than or equal to the load is selected as the target energy storage conversion unit for supplying power to the power system, or energy storage conversion units corresponding to multiple energy storage units whose sum of power values ​​is greater than or equal to the load are selected as the target energy storage conversion unit.

[0032] In a second aspect, an embodiment of the present application provides a black start device, including:

[0033] An acquisition module is used to predict the load of the power system and obtain energy storage information of the energy storage unit;

[0034] A processing module, used to determine the initial output power corresponding to the energy storage conversion unit according to the load and the energy storage information;

[0035] A control module is used to control the energy storage conversion unit to supply power to the power consumption system based on the initial output power, so that the output power of the target energy storage conversion unit matches the load.

[0036] In a third aspect, an embodiment of the present application provides an electronic device, including: a memory and a processor;

[0037] The memory is used to store computer instructions; the processor is used to execute the computer instructions stored in the memory to implement any method in the first aspect.

[0038] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, and the computer program is executed by a processor to implement any one of the methods in the first aspect.

[0039] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which implements any method in the first aspect when executed by a processor.

[0040] The black start method, device, electronic device, storage medium and program product provided in the embodiments of the present application predict the load of the power system and obtain the energy storage information of the energy storage unit; determine the initial output power corresponding to the energy storage converter unit according to the load and the energy storage information; and control the energy storage converter unit to supply power to the power system based on the initial output power so that the output power of the energy storage converter unit matches the load. During the black start process, the output power of the energy storage converter unit is determined based on the predicted load of the power system and the energy storage information of the energy storage unit, which can effectively reduce the probability of black start failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of a power system structure provided in an embodiment of the present application Figure 1 ;

[0042] Figure 2 A schematic diagram of a black start method provided in an embodiment of the present application Figure 1 ;

[0043] Figure 3 A schematic diagram of a black start method provided in an embodiment of the present application Figure 2 ;

[0044] Figure 4 A schematic diagram of a power system structure provided in an embodiment of the present application Figure 2 ;

[0045] Figure 5 A schematic diagram of a power system structure provided in an embodiment of the present application Figure 3 ;

[0046] Figure 6 A schematic diagram of the structure of a black start device provided in an embodiment of the present application;

[0047] Figure 7 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] In the embodiments of the present application, words such as "first" and "second" are used to distinguish the same or similar items with substantially the same functions and effects, and do not limit their order. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0050] It should be noted that in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0051] With the rapid development of distributed energy, distributed grid technology has gradually become an important means to solve the uneven distribution of energy and improve energy efficiency. However, during the operation of the grid, due to the randomness and intermittency of distributed power sources, the stability of the grid is prominent. After a power outage caused by a grid failure, how to quickly restore power supply becomes a key issue.

[0052] In the related art, after a power outage in the power grid, a black start method can be used to restore power supply. The so-called black start means that after the entire power grid system stops operating due to a fault, the entire system is completely blacked out and is in a completely "black" state, without relying on the help of other networks. By starting the generator sets or energy storage systems with self-starting capabilities in the system, the generator sets without self-starting capabilities are driven, gradually expanding the system recovery range and ultimately achieving the recovery of the entire system.

[0053] However, existing black start solutions mostly focus on quickly restoring power supply, but ignore the changes in grid load and the status of the energy storage system, which may lead to black start failure and affect the operation of the grid.

[0054] In view of this, the embodiments of the present application provide a black start method, device, electronic device, storage medium and program product. After a power outage in a power system, when a black start is performed, the load of the power system and the energy storage information of the energy storage unit are predicted to determine the power output mode of the energy storage conversion unit, and the operation of the energy storage conversion unit is controlled according to the power output mode of the energy storage conversion unit, which can effectively improve the success rate of the black start of the power system.

[0055] The following specific embodiments are used to describe in detail the technical solution of the present application and how the technical solution of the present application solves the above technical problems. The following specific embodiments can be implemented independently or in combination with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0056] Figure 1 A schematic diagram of a power system structure provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the power system includes a black start system and a power consumption system, and the power consumption system includes a DC bus and load equipment of the power consumption system connected to the DC bus.

[0057] The load device of the power system may be a power device connected to the power system.

[0058] The black start system comprises a controller, an energy storage conversion unit and an energy storage unit, and the energy storage conversion unit is connected to the DC bus.

[0059] In some embodiments, the black start system may include one or more energy storage and power conversion units, and each of the energy storage and power conversion units is connected to one or more energy storage units.

[0060] In some embodiments, the energy storage conversion unit is an energy storage converter, for example, a three-phase two-level converter, an NPC three-phase three-level converter, a T-type three-phase three-level converter, a three-phase cascade multi-level converter, etc., which is not limited in the embodiments of the present application.

[0061] It should be understood that the power consumption system described in the embodiments of the present application may include various types of power consumption systems, for example, a microgrid, a large power grid, a distributed power grid, a power station, a micro-microgrid, a power consumption system for household use, etc., and the embodiments of the present application are not limited to this.

[0062] The energy storage unit described in the embodiments of the present application may be a battery pack, an energy storage cabinet, a supercapacitor, etc. The embodiments of the present application do not limit the type of the energy storage unit.

[0063] Figure 1 The structure of the power system provided in the embodiment of the present application is briefly described. Figure 1 Based on the above, the following combination Figure 2 , taking the controller as the execution body, the black start method provided in the embodiment of the present application is explained.

[0064] Figure 2 A schematic diagram of a black start method provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, including:

[0065] S201. Predict the load of the power system, and obtain energy storage information of the energy storage unit.

[0066] In some embodiments, the load of the power system may refer to the power (electric energy) consumed by the power equipment connected to the power system during the normal operation of the power system. Figure 1 The information shown is the power, charge state and other information of the energy storage unit corresponding to the energy storage conversion unit in the black start system.

[0067] In some embodiments, the controller may predict the load of the electrical system based on historical loads of the electrical system.

[0068] Exemplarily, the historical load of the power system is obtained; the historical load is sampled to generate a time series based on the historical load; the time series of the historical load is fitted to generate a load trend of the power system; and the load of the power system is predicted based on the load trend.

[0069] After the controller obtains the historical load of the power system, it can sort the historical load from early to late in time, and sample the historical load in order based on a preset time interval to form a time series of the historical load. The time series of the historical load is fitted using a preset fitting model to generate the load trend of the power system (also known as load trend data or load trend graph), and the load of the time period to be predicted is extracted from the load trend as the predicted load of the power system.

[0070] In some embodiments, the controller may read the energy storage information from the energy storage unit.

[0071] In some embodiments, in order to further improve the accuracy of the predicted load, when the controller obtains the time series, it can also perform differential processing on the load data in the time series, and obtain the predicted load based on the time series after the differential processing.

[0072] For example, the difference processing can satisfy the following formula:

[0073]

[0074] in, For the t The historical load data after difference processing, For the t Historical load data, For the t-1 Historical load data.

[0075] The controller can fit the load forecast curve through the model expression to predict the future load value. The prediction model is as follows:

[0076]

[0077] in, For the t The load data after difference processing, The i-th is the historical load data value after difference processing; is the interference sequence; is the autoregression coefficient, is the moving average coefficient.

[0078] Optionally, the controller may also use regression analysis, artificial neural network, comprehensive model prediction, etc. to predict the load of the power system based on the historical load.

[0079] S202: Determine an initial output power corresponding to an energy storage conversion unit according to the load and the energy storage information.

[0080] In some embodiments, the energy storage conversion unit may refer to an energy storage conversion unit included in a black start system, and the black start system may include one or more energy storage conversion units.

[0081] When the black start system includes multiple energy storage conversion units, the controller obtains the load and the energy storage information, and can determine one or more target energy storage conversion units for black start from the multiple energy storage conversion units, so that the output power of the target energy storage conversion unit matches the load. When the black start system includes one energy storage conversion unit, the energy storage conversion power supply is the target energy storage conversion unit. The technical solution of the present application is described below by taking the black start system including multiple energy storage conversion units as an example.

[0082] For example, if the predicted load size is 10KW, the black start system includes 10 energy storage and conversion units, and each energy storage unit corresponds to an energy storage unit, then the controller can randomly select the energy storage and conversion unit corresponding to the sum of the power of multiple energy storage units greater than or equal to 10KW as the target energy storage and conversion unit. Alternatively, if there is an energy storage unit with a power greater than or equal to 10KW, the energy storage and conversion unit corresponding to the energy storage unit is determined as the target energy storage and conversion unit, for example, randomly select the energy storage and conversion units corresponding to 3 energy storage units (the sum of the power of the 3 energy storage units is greater than or equal to 10KW) as the target energy storage and conversion unit.

[0083] Optionally, to ensure smooth operation of the black start, when selecting an energy storage unit, an energy storage unit with a better state of charge may be selected, for example, an energy storage unit with a state of charge greater than a preset value (for example, 40%). The state of charge of an energy storage unit is the ratio of the remaining power of the energy storage unit to its capacity in a fully charged state, usually expressed as a percentage, and the state of charge of the energy storage unit may also be the SOC value of the energy storage unit.

[0084] Optionally, if there is an energy storage unit whose power is greater than or equal to the predicted load, the energy storage conversion unit corresponding to the energy storage unit can be preferentially selected as the target energy storage conversion unit to improve the stability of power output.

[0085] In some embodiments, the initial output power corresponding to the target energy storage conversion unit may include active reference power and reactive reference power.

[0086] When the controller determines the target energy storage conversion unit, the controller may determine the active reference power and the reactive reference power based on the load and the charge state of the target energy storage conversion unit.

[0087] Exemplarily, the active reference power and the reactive reference power may satisfy the following formula:

[0088]

[0089] in, is the active reference power of the i-th target energy storage converter unit, is the reactive reference power of the i-th target energy storage converter unit, is the charge state of the i-th target energy storage converter unit, For the predicted load.

[0090] S203: Based on the initial output power, control the energy storage conversion unit to supply power to the power consumption system, so that the output power of the energy storage conversion unit matches the load.

[0091] In some embodiments, the output electric energy of the energy storage and conversion unit matches the load may mean that the output electric energy of the energy storage and conversion unit is greater than or equal to the load.

[0092] When the controller obtains the initial output power of each target energy storage inverter, it can generate a control signal of the target energy storage inverter according to the initial control power, control the operation of the target energy storage inverter with the control signal, discharge the power supply unit corresponding to the target energy storage inverter, and provide power supply to the power consumption system to perform a black start on the power consumption system.

[0093] The black start method of the power system provided in the embodiment of the present application predicts the load of the power system and obtains the energy storage information of the black start system; determines the target energy storage conversion unit for black start from the multiple energy storage conversion units according to the load and the energy storage information, and the initial output power corresponding to the target energy storage conversion unit; and controls the target energy storage conversion unit to supply power to the power system based on the initial output power, so that the output electric energy of the target energy storage conversion unit matches the load. During the black start process, the output power of the energy storage conversion unit is determined based on the predicted load of the power system and the energy storage information of the black start system, which can effectively reduce the probability of black start failure.

[0094] exist Figure 2 Based on the embodiment shown, the following Figure 3 How to control the target energy storage conversion unit to supply power to the power system based on the initial output power in the aforementioned step S203 is described in detail.

[0095] Figure 3 A flow chart of another black start method provided in an embodiment of the present application is shown as follows: Figure 3 As shown, including:

[0096] S301. Within a target duration, control the target energy storage conversion unit to operate based on the initial output power, and collect the current value and voltage value output by the target energy storage conversion unit.

[0097] In some embodiments, there are also components between the target energy storage conversion unit and the AC bus for filtering the output current and transforming the current voltage. There will be a certain difference between the initial output power and the actual output power of the target energy storage conversion unit. In order to improve the success rate of black start, the actual output power of the target energy storage conversion unit needs to be considered when controlling its operation.

[0098] Figure 4 A schematic diagram of another power system structure provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, there are a filter resistor R1, a filter inductor L1, a filter capacitor C1, a transformer T and a ground GND1 between the energy storage conversion unit and the AC bus.

[0099] When the controller obtains the initial output power, it can control the target converter to operate at the initial output power within the target time (for example, 3 seconds), and collect the current value and voltage value output by the target energy storage converter unit through the voltage sensor and current sensor deployed between the filter capacitor C1 and the transformer T.

[0100] S302 , performing coordinate transformation on the voltage value and the current value, and converting the voltage value and the current value of the three-phase alternating current quantity into the voltage value and the current value of the two-phase direct current quantity.

[0101] Among them, the current value and voltage value of the target energy storage conversion unit output collected by the controller are three-phase AC current value and three-phase AC voltage value, for example, the voltage of axis a, axis b and axis c and current .

[0102] In some embodiments, in order to improve the accuracy of controlling the target energy storage converter unit, the controller can control the target energy storage converter by virtual synchronous machine (VSG) control. When calculating the output of the target energy storage converter based on VSG control, it is necessary to perform coordinate transformation on the three-phase AC voltage value and the three-phase AC current value to determine the corresponding actual output power.

[0103] Among them, VSG is a technology that embeds the mathematical model of the synchronous generator into the control algorithm of the inverter, simulates the static power electronic device as the operation technology of the rotating motor, and simulates the primary frequency and voltage regulation of the synchronous generator to enable it to have the functions of damping rapid fluctuations in voltage and frequency, automatic power distribution, and synchronous power system operation.

[0104] Exemplarily, converting the three-phase AC voltage value and the three-phase AC current value into a two-phase DC voltage value and a two-phase DC current value may satisfy the following formula:

[0105]

[0106]

[0107] Among them, the voltage value The two-phase DC voltage and current values ​​after the three-phase AC voltage value is converted is the two-phase DC current value after conversion of the three-phase AC current value, θ Control the output angle for VSG.

[0108] S303: Determine actual output power according to the two-phase DC current value and the two-phase DC voltage value.

[0109] In some embodiments, the actual output power also includes actual active power and actual reactive power. The actual active power may also be referred to as an active power measurement value, and the actual reactive power may also be referred to as a reactive power measurement value.

[0110] For example, the actual active power and the actual reactive power can satisfy the following formula:

[0111]

[0112] in, is the actual active power, is the actual reactive power.

[0113] S304. Based on the actual output power and the initial output power, obtain the electromotive force amplitude and output frequency of the target energy storage conversion unit.

[0114] In some embodiments, when the controller obtains the actual output power and the initial output power, the electromotive force amplitude of the target energy storage converter unit can be determined based on the following formula:

[0115]

[0116] in, is the virtual electromotive force reference value, n is the reactive power regulation coefficient, is the reactive power reference value, is the reactive power measurement value.

[0117] In some embodiments, the controller uses a virtual synchronous motor to control the output characteristics of a simulated synchronous generator to control the target energy storage converter unit, and the virtual synchronous motor rotor motion equation can be as follows:

[0118]

[0119] in, ω VSG controls the output angular frequency (output frequency), is the rated angular frequency, is the active power reference value, is the measured value of active power, J and D are the virtual inertia coefficient and virtual damping coefficient respectively.

[0120] S305. Obtain a control current of the target energy storage conversion unit according to the electromotive force amplitude, the output frequency, and the two-phase DC voltage value.

[0121] In some embodiments, the control current is used to indicate the output current of the target energy storage converter during operation, that is, during a black start, the current output by the target energy storage converter is equal to the control current.

[0122] When the controller obtains the electromotive force amplitude and the output frequency, the target energy storage converter can be controlled by using a voltage and current dual closed-loop control method.

[0123] For example, the control current of the target energy storage converter unit may satisfy the following formula:

[0124]

[0125] in, for d Shaft current reference value (control current), for q Shaft current reference value, is the voltage loop proportional coefficient, is the voltage loop integration coefficient, is the virtual impedance, is the filter capacitor, s is the differential operator.

[0126] S306. Acquire a control voltage of the target energy storage conversion unit according to the control current of the target energy storage conversion unit and the output frequency.

[0127] In some embodiments, the control voltage is used to characterize the output voltage (operating voltage) of the target energy storage converter during a black start process.

[0128] When the controller obtains the control current of the target energy storage conversion unit, it can obtain the control voltage of the target energy storage conversion unit based on the formula shown below.

[0129]

[0130] in, for d Shaft voltage reference value (control voltage), for q Shaft voltage reference value, is the current loop proportionality coefficient, is the current loop integral coefficient, For the filter inductor.

[0131] S307, converting the control voltage of the target energy storage conversion unit into a three-phase AC control voltage.

[0132] In some embodiments, when the controller obtains the control voltage of the target energy storage conversion unit, since the voltage is a two-phase DC voltage, the controller can also convert the two-phase DC voltage into a three-phase AC voltage.

[0133] For example, the controller can convert the voltage of two-phase DC quantity into the voltage of three-phase AC quantity by using the following formula:

[0134]

[0135] S308. Generate a power supply control signal for the target energy storage conversion unit according to the three-phase AC control voltage.

[0136] When the controller obtains the three-phase AC control voltage, it can perform analog-to-digital conversion on the three-phase AC control voltage and convert the three-phase AC control voltage into a power supply control signal (e.g., a pulse signal) of the target energy storage converter unit. Since the control voltage is determined by the control current and the output frequency, when the target energy storage converter unit is controlled to operate based on the power supply control signal converted from the control voltage, electric energy matching the control voltage, control current, and output frequency can be output.

[0137] In some embodiments, the three-phase AC control voltage is calculated based on the electromotive force amplitude and output frequency of the target energy storage converter unit. In order to reduce the excitation surge current generated when controlling the start-up of the target energy storage converter unit, when the controller calculates the electromotive force amplitude, it can gradually increase the virtual electromotive force reference value from 0 to the rated value within a preset time, thereby forming a slow-rise data of the control voltage.

[0138] For example, at the first moment when the target energy storage converter unit is started, the control voltage of the target energy storage converter unit is calculated based on the virtual electromotive force reference value of 0, at the second moment, the control voltage of the target energy storage converter unit is calculated based on the virtual electromotive force reference value of a (increase value), at the third moment, the control voltage of the target energy storage converter unit is calculated based on the virtual electromotive force reference value of 2a, until the Nth moment, the control voltage of the target energy storage converter unit is calculated based on the virtual electromotive force reference value of the rated value. Through the above method, the output of the target energy storage converter unit can have a slow rise process, which effectively reduces the excitation inrush current generated when the target energy storage converter unit is started, and improves the stability of the black start system.

[0139] S309: Control the target energy storage conversion unit to operate according to the power supply control signal to supply power to the power consumption system.

[0140] When the controller generates the power supply control signal, it can drive the switch of the target energy storage conversion unit to operate based on the power supply control signal, and supply power to the power consumption system with the control voltage and output frequency.

[0141] In summary, the black start method provided in the embodiment of the present application is based on predicting the load of the power system and calculating the power reference value of each unit according to the current state of each energy storage unit. It can effectively improve the success rate of the black start of the power system, and adopt VSG control to provide inertia and frequency support similar to that of a traditional synchronous generator. At the same time, it can reduce the no-load excitation surge current during startup, thereby improving the operating stability of the black system.

[0142] The black start method provided in the embodiment of the present application is described below with a specific example.

[0143] Figure 5 A schematic diagram of another power system provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, including:

[0144] Battery 201, energy storage converter 202, filter resistor R f 203. Filter inductance L f 204. Filter capacitor C f 205 , transformer T 206 , AC bus 207 , load 208 , power analyzer 209 , power prediction 210 , energy management 211 , voltage sensor VT 212 , current sensor CT 213 , coordinate transformation 214 , power calculation 215 , VSG control 216 , voltage and current dual closed-loop control 217 , coordinate transformation 218 , PWM control 219 and battery management 220 .

[0145] Among them, power prediction 210, energy management 211, coordinate transformation 214, power calculation 215, VSG control 216, voltage and current dual closed-loop control 217, coordinate transformation 218 and PWM control 219 can be functional modules of the controller in the above embodiments.

[0146] In some embodiments, when performing a black start of the power system, the power forecast 210 can determine the number of energy storage converters 202 used for black start and the active reference value that each energy storage converter 202 should output based on the historical load data of the power system obtained from the power analyzer 209 and the charge state of the battery pack obtained from the battery 201. P ref_i and reactive power reference value Q ref_i (initial output power).

[0147] The VSG control 216 can be based on the active reference value P ref_i and reactive power reference value Q ref_i The energy storage converter 202 is controlled to run for a preset time.

[0148] The coordinate transformation 214 collects the current value and the voltage value output by the energy storage converter 202 based on the voltage sensor VT 212 and the current sensor CT 213 , and converts the collected current value and voltage value into two-phase DC values.

[0149] The power calculation 215 calculates the actual output power of the energy storage converter 202 based on the current value and the voltage value of the two-phase DC quantity.

[0150] The VSG control 216 calculates the actual electromotive force amplitude E and the output frequency of the virtual synchronous machine based on the initial output power and the actual output power.

[0151] The voltage-current dual closed-loop control 217 obtains the control voltage of the energy storage converter 202 based on the actual electromotive force amplitude E and the output frequency.

[0152] The coordinate transformation 218 performs coordinate transformation on the control voltage, and transforms the two-phase DC control voltage into the three-phase AC control voltage.

[0153] The PWM control 219 compares the control voltage of the three-phase AC quantity with the triangular carrier to obtain the control pulse g of the converter switch, thereby driving the switch action to achieve energy conversion, as well as voltage and frequency control.

[0154] Based on the above embodiments, the embodiments of the present application also provide a black start device.

[0155] Figure 6 A schematic diagram of the structure of a black start device 60 provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, including:

[0156] The acquisition module 601 is used to predict the load of the power system and to acquire energy storage information of the energy storage unit.

[0157] The processing module 602 is used to determine the initial output power corresponding to the energy storage conversion unit according to the load and the energy storage information.

[0158] The control module 603 is used to control the energy storage and conversion unit to supply power to the power consumption system based on the initial output power, so that the output power of the energy storage and conversion unit matches the load.

[0159] In some embodiments, the control module 603 is also used to control the energy storage conversion unit to operate based on the initial output power within the target duration, and collect the current value and voltage value output by the target energy storage conversion unit; determine the actual output power according to the current value and the voltage value; based on the actual output power and the initial output power, control the target energy storage conversion unit to supply power to the power consumption system.

[0160] In some embodiments, the control module 603 is also used to obtain the electromotive force amplitude and output frequency of the energy storage conversion unit based on the actual output power and the initial output power; generate a power supply control signal of the energy storage conversion unit according to the electromotive force amplitude and the output frequency; and control the operation of the energy storage conversion unit according to the power supply control signal so that the energy storage conversion unit outputs electric energy to the power consumption system according to the electromotive force amplitude and the output frequency.

[0161] In some embodiments, the collected current value and voltage value output by the energy storage conversion unit are three-phase AC current value and three-phase AC voltage value, and the processing module 602 is also used to perform coordinate transformation on the three-phase AC voltage value and the three-phase AC current value, and convert the three-phase AC voltage value and the three-phase AC current value into two-phase DC voltage value and two-phase DC current value.

[0162] In some embodiments, the control module 603 is also used to obtain the control current of the energy storage conversion unit according to the electromotive force amplitude, the output frequency, and the two-phase DC voltage value; the control current is used to characterize that the energy storage conversion unit outputs current with the control current; the control voltage of the energy storage conversion unit is obtained according to the control current and the output frequency of the energy storage conversion unit; the control voltage is used to characterize the voltage of the output current of the energy storage conversion unit; the control voltage of the energy storage conversion unit is converted into a three-phase AC control voltage; the power supply control signal of the target energy storage conversion unit is generated according to the three-phase AC control voltage; the power supply control signal is used to instruct the energy storage conversion unit to output electric energy to the power consumption system according to the control voltage and the control current.

[0163] In some embodiments, the acquisition module 601 is also used to obtain the historical load of the power system; sample the historical load to generate a time series based on the historical load; fit the time series of the historical load to generate a load trend of the power system; and predict the load of the power system based on the load trend.

[0164] In some embodiments, there are multiple energy storage conversion units, each of which is connected to at least one energy storage unit. The processing module 602 is also used to obtain power information of the energy storage units connected to each energy storage conversion unit; according to the power information and the predicted load of the power consumption system, an energy storage conversion unit corresponding to an energy storage unit whose power value is greater than or equal to the load is selected as the target energy storage conversion unit, or an energy storage conversion unit corresponding to multiple energy storage units whose sum of power values ​​is greater than or equal to the load is selected as the target energy storage conversion unit.

[0165] The black start device provided in the embodiment of the present application can execute the black start device method provided in any of the above embodiments, and its principles and technical effects are similar, which will not be repeated here.

[0166] An embodiment of the present application also provides an electronic device.

[0167] Figure 7 A schematic diagram of the structure of an electronic device 70 provided in an embodiment of the present application is shown in FIG. Figure 7As shown, the electronic device may include: a transceiver 701, a processor 702, and a memory 703. The electronic device may be the controller in any of the above embodiments.

[0168] The processor 702 executes the computer-executable instructions stored in the memory, so that the processor 702 executes the solution in the above embodiment. The processor 702 can be a general-purpose processor, including a central processing unit CPU, a network processor (network processor, NP), etc.; it can also be a digital signal processor DSP, an application-specific integrated circuit ASIC, a field programmable gate array FPGA or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components.

[0169] The memory 703 is connected to the processor 702 via a system bus and completes communication between them. The memory 703 is used to store computer program instructions.

[0170] The transceiver 701 can receive load data and send power supply control signals.

[0171] Optionally, the electronic device 70 may further include a communication interface to communicate and interact with an external or internal device through the communication interface. The external device may be, for example, a client (eg, a mobile phone, a tablet).

[0172] The system bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The system bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus. The transceiver is used to realize the communication between the database access device and other computers (such as clients, read-write libraries, and read-only libraries). The memory may include random access memory (RAM) and may also include non-volatile memory.

[0173] An embodiment of the present application also provides a chip for running instructions, which is used to execute the technical solution of the black start method in the above embodiment.

[0174] In an embodiment of the present application, a computer-readable storage medium is also provided, on which a computer program is stored. When the computer program is executed by a processor, the technical solution of the above-mentioned black start method embodiment is implemented. The implementation principle and technical effect are similar and will not be repeated here.

[0175] In one possible implementation, a computer-readable medium may include a random access memory (RAM), a read-only memory (ROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage device, or any other medium that is intended to carry or store the required program code in the form of instructions or data structures and can be accessed by a computer. Moreover, any connection is appropriately referred to as a computer-readable medium. For example, if the software is transmitted from a website, server or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, radio and microwave are included in the definition of the medium. Disks and optical disks as used herein include optical disks, laser disks, optical disks, digital versatile disks (DVD), floppy disks and Blu-ray disks, where disks usually reproduce data magnetically, while optical disks reproduce data optically using lasers. Combinations of the above should also be included in the scope of computer-readable media.

[0176] A computer program product is also provided in an embodiment of the present application, including a computer program. When the computer program is executed by a processor, the technical solution of the above-mentioned black start method embodiment is implemented. The implementation principle and technical effect are similar and will not be repeated here.

[0177] In the specific implementation of the above-mentioned terminal device or server, it should be understood that the processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor can be a microprocessor or the processor can be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor.

[0178] Those skilled in the art will appreciate that all or part of the steps of any of the above method embodiments may be completed by hardware associated with program instructions. The aforementioned program may be stored in a computer-readable storage medium, and when the program is executed, all or part of the steps of the above method embodiments are executed.

[0179] If the technical solution of the present application is implemented in the form of software and sold or used as a product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the technical solution of the present application can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a computer program or several instructions. The computer software product enables a computer device (which can be a personal computer, a server, a network device, or a similar electronic device) to perform all or part of the steps of the method described in the embodiment of the present application.

[0180] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present application.

[0181] It should be further noted that, although the various steps in the flowchart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowchart may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0182] It should be understood that the above-mentioned device embodiments are only illustrative, and the device of the present application can also be implemented in other ways. For example, the division of units / modules in the above-mentioned embodiments is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units, modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed.

[0183] In addition, unless otherwise specified, each functional unit / module in each embodiment of the present application may be integrated into one unit / module, each unit / module may exist physically separately, or two or more units / modules may be integrated together. The above-mentioned integrated unit / module may be implemented in the form of hardware or in the form of a software program module.

[0184] If the integrated unit / module is implemented in the form of hardware, the hardware may be a digital circuit, an analog circuit, etc. The physical implementation of the hardware structure includes but is not limited to transistors, memristors, etc. Unless otherwise specified, the processor may be any appropriate hardware processor, such as CPU, GPU, FPGA, DSP, and ASIC, etc. Unless otherwise specified, the storage unit may be any appropriate magnetic storage medium or magneto-optical storage medium, such as Resistive Random Access Memory (RRAM), Dynamic Random Access Memory (DRAM), Static Random Access Memory (SRAM), Enhanced Dynamic Random Access Memory (EDRAM), High-Bandwidth Memory (HBM), Hybrid Memory Cube (HMC), etc.

[0185] If the integrated unit / module is implemented in the form of a software program module and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a memory, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned memory includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0186] In the above embodiments, the description of each embodiment has its own emphasis. For the part not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0187] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A black start method, characterized in that: include: Predict the load of the power system and obtain the energy storage information of the energy storage unit; Determining an initial output power corresponding to an energy storage conversion unit according to the load and the energy storage information; Within the target duration, controlling the energy storage conversion unit to operate at the initial output power, and collecting the current value and voltage value output by the energy storage conversion unit; Determining actual output power according to the current value and the voltage value; Within a preset time period, based on the actual output power, the initial output power and the virtual electromotive force reference value, the output frequency of the energy storage conversion unit and the electromotive force amplitude based on the time series are obtained; The virtual electromotive force reference value increases from zero to a rated value at a preset amplitude within the preset time period; Generating a time-series-based power supply control signal of the energy storage conversion unit according to the time-series-based electromotive force amplitude and the output frequency; The energy storage and conversion unit is controlled to operate according to the power supply control signal, so that the energy storage and conversion unit outputs electric energy to the power consumption system according to the electromotive force amplitude and the output frequency.

2. The method according to claim 1, characterized in that The load prediction of the power system includes: Obtaining the historical load of the power system; Sampling the historical load to generate a time series based on the historical load; Fitting the time series of the historical load to generate a load trend of the power system; The load of the power system is predicted according to the load trend.

3. The method according to claim 2, characterized in that The collected current value and voltage value output by the energy storage conversion unit are three-phase AC current value and three-phase AC voltage value. Before determining the actual output power according to the current value and the voltage value, the method further includes: Coordinate transformation is performed on the three-phase AC voltage value and the three-phase AC current value, and the three-phase AC voltage value and the three-phase AC current value are converted into two-phase DC voltage value and two-phase DC current value.

4. The method according to claim 3, characterized in that Generating a power supply control signal of the energy storage conversion unit according to the electromotive force amplitude and the output frequency, including: According to the electromotive force amplitude, the output frequency, and the two-phase DC voltage value, a control current of the energy storage conversion unit is obtained; the control current is used to characterize that the energy storage conversion unit outputs current with the control current; According to the control current of the energy storage conversion unit and the output frequency, a control voltage of the energy storage conversion unit is obtained; the control voltage is used to characterize the output voltage of the energy storage conversion unit; Converting the control voltage of the energy storage converter unit into a three-phase AC control voltage; A power supply control signal of the energy storage conversion unit is generated according to the three-phase AC control voltage; the power supply control signal is used to instruct the energy storage conversion unit to output electric energy to the power consumption system according to the control voltage and the control current.

5. The method according to any one of claims 1 to 3, characterized in that: There are a plurality of energy storage and conversion units, each of which is connected to at least one energy storage unit, and the method further comprises: Obtaining power information of energy storage units connected to each energy storage conversion unit; Based on the power information and the predicted load of the power system, an energy storage conversion unit corresponding to an energy storage unit whose power value is greater than or equal to the load is selected as the target energy storage conversion unit for supplying power to the power system, or energy storage conversion units corresponding to multiple energy storage units whose sum of power values ​​is greater than or equal to the load are selected as the target energy storage conversion unit.

6. A black start device, characterized in that: include: An acquisition module is used to predict the load of the power system and obtain energy storage information of the energy storage unit; A processing module, used to determine the initial output power corresponding to the energy storage conversion unit according to the load and the energy storage information; A control module is used to control the energy storage conversion unit to operate at the initial output power within a target duration, and collect the current value and voltage value output by the energy storage conversion unit; determine the actual output power according to the current value and the voltage value; within a preset duration, based on the actual output power, the initial output power and the virtual electromotive force reference value, obtain the output frequency of the energy storage conversion unit and the electromotive force amplitude based on the time series; The virtual electromotive force reference value increases from zero to a rated value at a preset amplitude within the preset time period; a time series-based power supply control signal of the energy storage conversion unit is generated according to the time series-based electromotive force amplitude and the output frequency; and the energy storage conversion unit is controlled to operate according to the power supply control signal so that the energy storage conversion unit outputs electric energy to the power consumption system according to the electromotive force amplitude and the output frequency.

7. An electronic device, characterized in that: include: Memory for storing computer programs; A processor, configured to execute the computer program to implement the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and the computer program is executed by a processor to implement the method according to any one of claims 1 to 5.

9. A computer program product, characterized in that The method comprises a computer program, which, when executed by a controller, implements the method according to any one of claims 1 to 5.

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