A control method and control system for a generator

Abstract

The application provides a control method and a control system of a generator. An output end of the generator is connected to an input end of an energy storage converter. An output end of the energy storage converter is used to connect at least one battery pack. The generator is used to charge the battery pack. The method comprises the following steps: determining an actual rotating speed of the generator, an actual output current and an actual output voltage of the output end of the generator in a two-phase rotating coordinate system; determining a first expected voltage of the input end of the energy storage converter according to the actual rotating speed, the actual output current and the actual output voltage, and according to a rotating speed control strategy; determining a second expected voltage of the input end of the energy storage converter according to the actual output current and the actual output voltage, and according to an excitation control strategy; and controlling the input end voltage of the energy storage converter according to the first expected voltage and the second expected voltage, so as to control the output end voltage of the generator.

Description

Technical Field

[0001] This application relates to the field of generator control technology, and in particular to a generator control method and control system. Background Technology

[0002] In existing technologies, generators are used in energy storage systems to charge multiple battery packs within the system. To achieve excitation and speed control of the generator, a control unit is required, consisting of a speed control system and an excitation control system. The generator is typically a diesel generator. The speed control system uses a governor to automatically adjust the diesel fuel supply to the generator based on load changes, thereby altering the generator's speed. The excitation control system automatically adjusts the excitation current of the diesel generator based on voltage changes at the generator side connected to the energy storage system. However, equipping the diesel generator with a control system results in higher costs. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide at least one generator control method and control system. By setting an energy storage converter between the generator and the battery pack that needs to be charged, and by determining the actual speed of the generator, the actual output current and the actual output voltage of the generator in a two-phase rotating coordinate system, and by determining the first desired voltage and the second desired voltage in the two-phase rotating coordinate system to be input to the energy storage converter according to the speed control strategy and the excitation control strategy respectively, the output voltage of the generator can be controlled by controlling the input voltage of the energy storage converter. This solves the technical problem of high cost caused by the need to connect an external control unit to the generator to perform speed control and excitation control in the prior art, and achieves the technical effect of reducing costs by directly using the energy storage converter connected to the battery pack for speed control and excitation control.

[0004] This application mainly includes the following aspects:

[0005] In a first aspect, embodiments of this application provide a control method for a generator, wherein the output terminal of the generator is connected to the input terminal of an energy storage converter, the output terminal of the energy storage converter is used to connect to at least one battery pack, and the generator is used to charge the battery pack. The method includes: determining the actual rotational speed of the generator, the actual output current of the generator's output terminal in a two-phase rotating coordinate system, and the actual output voltage; determining a first desired voltage at the input terminal of the energy storage converter according to the actual rotational speed, the actual output current, and the actual output voltage, following a speed control strategy; determining a second desired voltage at the input terminal of the energy storage converter according to the actual output current and the actual output voltage, following an excitation control strategy; and controlling the input terminal voltage of the energy storage converter according to the first desired voltage and the second desired voltage to control the output terminal voltage of the generator.

[0006] Optionally, the speed control strategy includes a speed control loop, a torque control loop, and a first current control loop set in sequence, and the excitation control strategy includes a voltage control loop and a second current control loop set in sequence, wherein each control loop performs proportional-integral control.

[0007] Optionally, the actual output current includes the actual direct-axis current and the actual quadrature-axis current, and the actual output voltage includes the actual direct-axis voltage and the actual quadrature-axis voltage. The first desired voltage is used to indicate the direct-axis voltage of the input terminal of the energy storage converter in a two-phase rotating coordinate system, and the direct-axis voltage is used to achieve speed control for the generator. The second desired voltage is used to indicate the quadrature-axis voltage of the energy storage converter in a two-phase rotating coordinate system, and the quadrature-axis voltage is used to achieve excitation control for the generator.

[0008] Optionally, the first desired voltage is determined by: comparing the rated speed of the generator with the actual speed, and performing proportional-integral control on the comparison result through the speed control loop to obtain the desired electromagnetic torque of the generator; comparing the actual electromagnetic torque of the generator with the desired electromagnetic torque, and performing proportional-integral control on the comparison result through the torque control loop to obtain the desired direct-axis current of the generator, wherein the actual electromagnetic torque is calculated based on the actual speed, the actual output current, and the actual output voltage; comparing the actual direct-axis current of the generator with the desired direct-axis current, and performing proportional-integral control on the comparison result through the first current control loop to obtain the first desired voltage.

[0009] Optionally, the second desired voltage is determined by comparing the actual output voltage of the generator with the desired output voltage and performing proportional-integral control on the comparison result through the voltage control loop to obtain the desired quadrature-axis current; comparing the actual quadrature-axis current of the generator with the desired quadrature-axis current and performing proportional-integral control on the comparison result through the second current control loop to obtain the second desired voltage.

[0010] Optionally, the actual speed of the generator can be determined by: observing the flux linkage of the generator to obtain the actual speed of the generator, or by installing a speed measuring device on the generator to obtain the actual speed of the generator.

[0011] Optionally, the generator and the energy storage converter are connected via a three-phase power transmission line. The actual output current and actual output voltage of the generator in a two-phase rotating coordinate system are determined by: obtaining the three-phase output voltage and three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system; calculating the electrical angle of the generator based on the actual rotational speed of the generator; and calculating the actual output current and actual output voltage based on the electrical angle, the three-phase output voltage, and the three-phase output current.

[0012] Optionally, the input terminal of the energy storage converter includes a voltage sampling device and a current sampling device, wherein the voltage sampling device is used to collect the three-phase output voltage and the current sampling device is used to collect the three-phase output current.

[0013] Secondly, embodiments of this application also provide a control system, the control system comprising: a generator; an energy storage converter, wherein the output terminal of the generator is connected to the input terminal of the energy storage converter, the output terminal of the energy storage converter is used to connect to at least one battery pack, the generator is used to charge the battery pack, wherein the controller of the energy storage converter is configured to: execute the generator control method as described in the first aspect or any possible implementation of the first aspect.

[0014] Optionally, the controller of the energy storage converter is configured to: obtain the actual speed of the generator by observing the flux linkage of the generator, or obtain the actual speed of the generator by installing a speed measuring device on the generator.

[0015] Optionally, the generator and the energy storage converter are connected via a three-phase power transmission line. The input terminal of the energy storage converter includes a voltage sampling device and a current sampling device. The voltage sampling device is used to collect the three-phase output voltage of the three-phase power transmission line in a three-phase stationary coordinate system, and the current sampling device is used to collect the three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system.

[0016] This application provides a generator control method and control system. The generator's output terminal is connected to the input terminal of an energy storage converter. The output terminal of the energy storage converter is used to connect to at least one battery pack. The generator is used to charge the battery pack. The method includes: determining the generator's actual rotational speed, the generator's actual output current in a two-phase rotating coordinate system, and the generator's actual output voltage; determining a first desired voltage at the input terminal of the energy storage converter according to the actual rotational speed, the actual output current, and the actual output voltage, following a speed control strategy; determining a second desired voltage at the input terminal of the energy storage converter according to the actual output current and the actual output voltage, following an excitation control strategy; and controlling the input terminal voltage of the energy storage converter according to the first desired voltage and the second desired voltage to control the generator's output terminal voltage. By installing an energy storage converter between the generator and the battery pack that needs charging, and by determining the generator's actual speed, actual output current, and actual output voltage in a two-phase rotating coordinate system, and by determining the first and second desired voltages to be input to the energy storage converter in the two-phase rotating coordinate system according to speed control and excitation control strategies respectively, the generator's output voltage can be controlled by controlling the input voltage of the energy storage converter. This solves the technical problem of high cost caused by the need for an external control unit to perform speed control and excitation control in the prior art, and achieves the technical effect of reducing costs by directly using the energy storage converter connected to the battery pack for speed control and excitation control.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1A schematic diagram of a control system provided in an embodiment of this application is shown.

[0020] Figure 2 A flowchart of a generator control method provided in an embodiment of this application is shown.

[0021] Figure 3 A control block diagram of the generator control method provided in an embodiment of this application is shown.

[0022] Figure 4 A functional block diagram of a generator control device provided in an embodiment of this application is shown.

[0023] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0025] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0026] In existing technologies, generators are connected to the battery pack of energy storage systems to charge the battery pack. During the charging process, a control unit is typically configured to control the generator's excitation and speed, thereby controlling the charging process of the generator to the battery pack. However, configuring a control unit for the generator is costly, and some older generators require additional control units to charge the battery pack.

[0027] Based on this, this application provides a generator control method and control system. By setting an energy storage converter between the generator and the battery pack that needs to be charged, the actual speed of the generator, the actual output current and actual output voltage of the generator in a two-phase rotating coordinate system are determined. Then, according to the speed control strategy and the excitation control strategy, the first desired voltage and the second desired voltage in the two-phase rotating coordinate system to be input to the energy storage converter are determined. By controlling the input voltage of the energy storage converter, the output voltage of the generator is controlled. This solves the technical problem of high cost caused by the need for an external control unit to perform speed control and excitation control in the prior art. It achieves the technical effect of reducing costs by directly using the energy storage converter connected to the battery pack for speed control and excitation control, as detailed below:

[0028] Please see Figure 1 , Figure 1 This is a schematic diagram of a control system provided in an embodiment of this application. Figure 1 As shown, the control system provided in this application embodiment includes: a generator M; an energy storage converter PCS, wherein the output terminal of the generator is connected to the input terminal of the energy storage converter, the output terminal of the energy storage converter is used to connect to at least one battery pack, the generator is used to charge the battery pack, and the controller of the energy storage converter is configured to execute the generator control method provided in this application.

[0029] In other words, the electrical energy generated by the generator is transmitted to at least one battery pack through an energy storage converter, and at least one battery pack is used to connect to the power grid to achieve grid connection. The generator can be any of the following: diesel generator, synchronous generator, asynchronous generator, hydroelectric generator, or steam turbine generator.

[0030] Specifically, the generator and the energy storage converter are connected via a three-phase power transmission line. The input terminal of the energy storage converter includes a voltage sampling device and a current sampling device. The voltage sampling device is used to collect the three-phase output voltage of the three-phase power transmission line in a three-phase stationary coordinate system, and the current sampling device is used to collect the three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system.

[0031] like Figure 1 As shown, the generator's output terminal is connected to the energy storage converter's input terminal via a three-phase power transmission line. The three-phase power transmission line includes an A-phase power transmission line, a B-phase power transmission line, and a C-phase power transmission line. The energy storage converter's input terminal refers to the grid connection port of the energy storage converter or the connection port used to connect the generator.

[0032] Furthermore, voltage sampling devices and current sampling devices are installed on phase A power transmission lines, phase B power transmission lines, and phase C power transmission lines to collect the three-phase output voltage and three-phase output current output by the generator in a three-phase stationary coordinate system. That is, the three-phase output voltage includes phase A output voltage, phase B output voltage, and phase C output voltage, and the three-phase output current includes phase A output current, phase B output current, and phase C output current.

[0033] The controller of the energy storage converter is configured to obtain the actual speed of the generator by observing the flux linkage of the generator, or by installing a speed measuring device on the generator to obtain the actual speed of the generator.

[0034] In other words, the generator can also be equipped with a speed measuring device, which is used to acquire the actual speed of the generator and send the actual speed to the controller of the energy storage converter. This allows the controller of the energy storage converter to directly acquire the actual speed of the generator from the speed measuring device, or to obtain the actual speed of the generator by observing the flux linkage of the three-phase output voltage and three-phase output current.

[0035] In other words, the controller of the energy storage converter obtains the three-phase output voltage through a voltage sampling device, obtains the three-phase output current through a current sampling device, and can also obtain the actual speed of the generator through a speed measurement device. In this way, the controller of the energy storage converter can perform speed control and excitation control without the need to build a control unit for the generator, thereby saving costs.

[0036] Please see Figure 2 , Figure 2 This is a flowchart illustrating a generator control method provided in an embodiment of this application. Figure 2 As shown in the embodiment of this application, the generator control method includes the following steps:

[0037] S101: Determine the actual rotational speed of the generator, the actual output current of the generator's output terminal in a two-phase rotating coordinate system, and the actual output voltage.

[0038] Specifically, the actual speed of the generator is determined by the following methods: by observing the flux linkage of the generator to obtain the actual speed of the generator, or by installing a speed measuring device on the generator to obtain the actual speed of the generator.

[0039] Specifically, the actual output current and actual output voltage of the generator in a two-phase rotating coordinate system are determined by the following methods: obtaining the three-phase output voltage and three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system; calculating the electrical angle of the generator based on the actual rotational speed of the generator; and calculating the actual output current and actual output voltage based on the electrical angle, the three-phase output voltage, and the three-phase output current.

[0040] For example, the actual speed n of the generator can be acquired through external speed sensors, encoders, flux linkage monitoring, etc., and then the electric angular velocity ω of the generator can be calculated using the actual speed n and the number of pole pairs p of the generator. The electrical angle θ of the generator is then calculated using the electrical angular velocity and time t, where θ = ω × t. Alternatively, the electrical angle can be obtained by sampling the three-phase output voltage, three-phase output current, and actual rotational speed, and using a phase-locked loop (PLL). This application does not limit the specific implementation method. Furthermore, using the generator's electrical angle, three-phase output voltage, and three-phase output current, the actual output current and actual output voltage in a two-phase rotating coordinate system can be calculated.

[0041] The actual output current includes the actual direct-axis current and the actual quadrature-axis current, and the actual output voltage includes the actual direct-axis voltage and the actual quadrature-axis voltage.

[0042] Specifically, the actual output current and actual output voltage in the two-phase rotating coordinate system are calculated using the following formulas:

[0043]

[0044] In formulas (1) to (4), U A This refers to the A-phase output voltage in the three-phase output voltage, U B This refers to the B-phase output voltage in the three-phase output voltage, U C This refers to the C-phase output voltage in the three-phase output voltage, U d This refers to the actual direct-axis voltage in the actual output voltage, U. q This refers to the actual quadrature-axis voltage (I) in the actual output voltage. A This refers to the A-phase output current, I, in the three-phase output voltage. B This refers to the output current of phase B in the three-phase output voltage, I. C This refers to the C-phase output current, I, in the three-phase output voltage. d This refers to the actual direct-axis current in the actual output current, I. q This refers to the actual quadrature-axis current in the actual output current, and θ refers to the electrical angle of the generator.

[0045] Furthermore, by acquiring the generator's actual speed and the generator's three-phase output voltage and three-phase output current in the three-phase stationary coordinate system in real time, the generator's actual output current and actual output voltage in the two-phase rotating coordinate system can be calculated.

[0046] Among them, the mechanical torque T of the generator m Equal to the mechanical power P of the generator m The ratio of the actual rotational speed ω of the generator to the actual rotational speed ω. If the generator is a diesel generator, the energy generated by diesel combustion is converted into the kinetic energy of the generator rotor. Therefore, the magnitude of the mechanical torque depends on the amount of diesel fuel supplied; the larger the fuel supply, the greater the torque. m The larger the value, the greater the potential energy. Furthermore, the generator's rotor kinetic energy will be converted into electrical energy to charge the energy storage system's battery pack. If the energy storage system's charging power is P... e Then the electromagnetic torque T of the generator e Equal to charging power P e The ratio of the actual rotational speed ω of the generator to the actual rotational speed ω of the generator. Therefore, the rotor motion equation when the generator charges the energy storage system can be expressed as: J refers to the moment of inertia.

[0047] Furthermore, in the mechanical torque T of the generator m When increased, the electromagnetic torque T can be controlled. e It also increases synchronously, by controlling T m =T e To control The value is 0, meaning the charging power P of the energy storage system is controlled. e The method used is to maintain a constant generator speed. The charging power of the energy storage system is equivalent to the active power output of the generator. In other words, the generator speed is controlled by controlling the electromagnetic torque, that is, by controlling the active power output of the generator. Therefore, when the actual generator speed increases, it is necessary to increase the electromagnetic torque, or in other words, increase the charging power, to convert kinetic energy into electrical energy and reduce the actual speed; when the actual generator speed decreases, it is necessary to decrease the charging power to reduce the conversion of kinetic energy into electrical energy and increase the actual generator speed.

[0048] The generator's output voltage depends on the excitation current, i.e., the reactive current, and the output voltage U. gen Equal to excitation current I f With excitation reactance X m The product of these two factors means that the excitation reactance is essentially constant. Therefore, the generator's output voltage can be controlled by controlling the generator's excitation current through the energy storage converter; this control of the output voltage is commonly referred to as excitation control.

[0049] Since the power generated by the direct axis is equivalent to active power, which can be used to analyze the generator speed control, and the power generated by the quadrature axis is equivalent to reactive power, which can be used to analyze the generator excitation control, it is necessary to convert the three-phase output voltage and three-phase output current of the generator in the three-phase stationary coordinate system to two-phase rotating coordinate system in order to perform speed control and excitation control.

[0050] S102: Based on the actual rotational speed, the actual output current, and the actual output voltage, determine the first desired voltage at the input terminal of the energy storage converter according to the rotational speed control strategy.

[0051] The speed control strategy includes sequentially setting a speed control loop, a torque control loop, and a first current control loop, with each control loop performing proportional-integral control. The first desired voltage is used to indicate the direct-axis voltage at the input terminal of the energy storage converter in a two-phase rotating coordinate system, and the direct-axis voltage is used to achieve speed control for the generator.

[0052] Specifically, the first desired voltage is determined as follows: The rated speed of the generator is compared with the actual speed, and the comparison result is subjected to proportional-integral control through the speed control loop to obtain the desired electromagnetic torque of the generator; the actual electromagnetic torque of the generator is compared with the desired electromagnetic torque, and the comparison result is subjected to proportional-integral control through the torque control loop to obtain the desired direct-axis current of the generator, wherein the actual electromagnetic torque is calculated based on the actual speed, the actual output current, and the actual output voltage; the actual direct-axis current of the generator is compared with the desired direct-axis current, and the comparison result is subjected to proportional-integral control through the first current control loop to obtain the first desired voltage.

[0053] Please see Figure 3 , Figure 3 This is a control block diagram of the generator control method provided in an embodiment of this application. Figure 3 As shown, a three-loop PI control is set in the speed control strategy, including an outer speed control loop, a middle torque control loop, and an inner first current control loop. The outer loop uses the speed control loop for closed-loop control, comparing the generator's rated speed ω... cmd The speed error between the actual speed ω and the actual speed is obtained. This speed error is then processed by a proportional-integral (PI) calculation through a speed control loop to obtain the desired electromagnetic torque T of the generator. cmd The middle loop uses a torque control loop for closed-loop control, where the active power output by the generator is equal to the output voltage U, current I, and power factor. The product of these is also equal to the actual electromagnetic torque T of the generator. fbkThe ratio of the actual rotational speed n to the actual rotational speed n (i.e. Therefore, the actual electromagnetic torque T of the generator can be calculated. fbk Compare the actual electromagnetic torque T fbk and desired electromagnetic torque T cmd The electromagnetic torque error between the two is obtained, and then the electromagnetic torque error is calculated using a proportional-integral (PI) operation through a torque control loop to obtain the desired direct-axis current. The inner loop uses the first current control loop for closed-loop control, controlling the three-phase output current I of the generator. A I B I C The electrical angle θ calculated from the actual rotational speed is converted into the actual direct-axis current I in a two-phase rotating coordinate system. d Compare the actual direct-axis current I of the generator d and desired direct-axis current The comparison result is then processed by a proportional-integral (PI) calculation through the first current control loop to obtain the first desired voltage. And the first desired voltage is the desired direct-axis voltage.

[0054] return Figure 2 S103: Based on the actual output current and the actual output voltage, determine the second desired voltage at the input terminal of the energy storage converter according to the excitation control strategy.

[0055] The excitation control strategy includes a voltage control loop and a second current control loop arranged sequentially, with each control loop performing proportional-integral control. The second desired voltage is used to indicate the quadrature-axis voltage of the energy storage converter in a two-phase rotating coordinate system, and the quadrature-axis voltage is used to achieve excitation control for the generator.

[0056] Specifically, the second desired voltage is determined by comparing the actual output voltage of the generator with the desired output voltage, and performing proportional-integral control on the comparison result through the voltage control loop to obtain the desired quadrature-axis current; comparing the actual quadrature-axis current of the generator with the desired quadrature-axis current, and performing proportional-integral control on the comparison result through the second current control loop to obtain the second desired voltage.

[0057] return Figure 3 The excitation control strategy employs a dual-loop PI control, comprising an outer voltage control loop and an inner second current control loop. For example, the three-phase output voltage U of the generator... A U B U C The electrical angle θ calculated from the actual rotational speed is converted into the actual output voltage in a two-phase rotating coordinate system, and the amplitude U of the actual output voltage is determined.fbk Compare the amplitude U of the actual output voltage of the generator. fbk and the amplitude U of the desired output voltage cmd The output voltage error is obtained, and then the output voltage error is processed by a proportional-integral (PI) calculation through a voltage control loop to obtain the desired quadrature-axis current. That is, the excitation current, or reactive current; the three-phase output current I of the generator. A I B I C The electrical angle θ calculated from the actual rotational speed is converted into the actual quadrature-axis current I in a two-phase rotating coordinate system. q Compare the actual quadrature-axis current I of the generator q and desired cross-axis current The quadrature-axis current error is obtained, and then subjected to proportional-integral (PI) calculation through the second current control loop to obtain the second desired voltage. And the first desired voltage is the desired quadrature-axis voltage.

[0058] return Figure 2 S104: Control the input voltage of the energy storage converter according to the first desired voltage and the second desired voltage, so as to control the output voltage of the generator.

[0059] like Figure 3 As shown, the first desired voltage Second desired voltage By combining the electrical angle θ calculated based on the actual rotational speed, the desired modulation wave voltage in the three-phase stationary coordinate system is obtained. The voltage at the input of the energy storage inverter is controlled by PWM modulation to be the desired modulation wave voltage. In turn, the voltage output by the generator is controlled to conform to the desired modulation wave voltage, thereby realizing the speed control and excitation control of the generator.

[0060] Specifically, the desired modulation wave voltage in the three-phase stationary coordinate system is calculated using the following formula:

[0061]

[0062] In formulas (3) to (5), U A ′ This refers to the A-phase voltage, U, of the desired modulated wave voltage in a three-phase stationary coordinate system. B ′ This refers to the B-phase voltage, U, of the desired modulated wave voltage in a three-phase stationary coordinate system. C ′ This refers to the C-phase voltage of the desired modulated wave voltage in a three-phase stationary coordinate system. This refers to the first desired voltage. This refers to the second desired voltage, and θ refers to the electrical angle of the generator.

[0063] Based on the same application concept, this application also provides a generator control device corresponding to the generator control method provided in the above embodiments. Since the principle of the device in this application is similar to the generator control method in the above embodiments, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0064] like Figure 4 As shown, Figure 4 Functional modules of a generator control device provided in the embodiments of this application Figure 4 , Figure 4 A generator control device 10 provided in this application embodiment includes: a determining module 101, which determines the actual rotational speed of the generator, the actual output current of the generator in a two-phase rotating coordinate system, and the actual output voltage; a first calculation module 102, which determines a first desired voltage at the input terminal of the energy storage converter according to the actual rotational speed, the actual output current, and the actual output voltage, and follows a speed control strategy; a second calculation module 103, which determines a second desired voltage at the input terminal of the energy storage converter according to the actual output current and the actual output voltage, and follows an excitation control strategy; and a control module 104, which controls the input terminal voltage of the energy storage converter according to the first desired voltage and the second desired voltage, so as to control the output terminal voltage of the generator.

[0065] Based on the same application concept, see [link / reference] Figure 5 The diagram shown is a structural schematic of an electronic device provided in an embodiment of this application. The electronic device 20 includes a processor 201, a memory 202, and a bus 203. The memory 202 stores machine-readable instructions that can be executed by the processor 201. When the electronic device 20 is running, the processor 201 and the memory 202 communicate through the bus 203. When the machine-readable instructions are executed by the processor 201, the steps of the generator control method described in any of the above embodiments are executed.

[0066] Specifically, when the machine-readable instructions are executed by the processor 201, they can perform the following processes: determine the actual rotational speed of the generator, the actual output current of the generator's output terminal in a two-phase rotating coordinate system, and the actual output voltage; determine a first desired voltage at the input terminal of the energy storage converter according to the actual rotational speed, the actual output current, and the actual output voltage, following a speed control strategy; determine a second desired voltage at the input terminal of the energy storage converter according to the actual output current and the actual output voltage, following an excitation control strategy; and control the input terminal voltage of the energy storage converter according to the first desired voltage and the second desired voltage, thereby controlling the output terminal voltage of the generator.

[0067] Based on the same concept, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the generator control method provided in the above embodiments.

[0068] Specifically, the storage medium can be a general-purpose storage medium, such as a portable disk or hard disk. When the computer program on the storage medium is run, it can execute the above-mentioned generator control method. By setting an energy storage converter between the generator and the battery pack that needs to be charged, the actual speed of the generator, the actual output current and the actual output voltage of the generator in a two-phase rotating coordinate system are determined. The first desired voltage and the second desired voltage in a two-phase rotating coordinate system to be input to the energy storage converter are determined according to the speed control strategy and the excitation control strategy, respectively. By controlling the input voltage of the energy storage converter, the output voltage of the generator is controlled. This solves the technical problem of high cost caused by the need to connect an external control unit to the generator to perform speed control and excitation control in the prior art. It achieves the technical effect of reducing costs by directly using the energy storage converter connected to the battery pack for speed control and excitation control.

[0069] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0070] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0071] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0072] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0073] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for a generator, characterized in that, The generator's output is connected to the energy storage converter's input, and the energy storage converter's output is used to connect to at least one battery pack. The generator is used to charge the battery pack. The method includes: Determine the actual rotational speed of the generator, the actual output current of the generator's output terminal in a two-phase rotating coordinate system, and the actual output voltage. Based on the actual rotational speed, the actual output current, and the actual output voltage, the first desired voltage at the input terminal of the energy storage converter is determined according to the rotational speed control strategy. Based on the actual output current and the actual output voltage, the second desired voltage at the input terminal of the energy storage converter is determined according to the excitation control strategy; The input voltage of the energy storage converter is controlled according to the first desired voltage and the second desired voltage, so as to control the output voltage of the generator.

2. The method according to claim 1, characterized in that, The speed control strategy includes sequentially setting a speed control loop, a torque control loop, and a first current control loop; the excitation control strategy includes sequentially setting a voltage control loop and a second current control loop. Each control loop employs proportional-integral control.

3. The method according to claim 2, characterized in that, The actual output current includes the actual direct-axis current and the actual quadrature-axis current, and the actual output voltage includes the actual direct-axis voltage and the actual quadrature-axis voltage. Wherein, the first desired voltage is used to indicate the direct-axis voltage of the input terminal of the energy storage converter in a two-phase rotating coordinate system, and the direct-axis voltage is used to realize speed control for the generator; the second desired voltage is used to indicate the quadrature-axis voltage of the energy storage converter in a two-phase rotating coordinate system, and the quadrature-axis voltage is used to realize excitation control for the generator.

4. The method according to claim 3, characterized in that, The first desired voltage is determined in the following manner: The rated speed of the generator is compared with the actual speed, and the comparison result is subjected to proportional-integral control through the speed control loop to obtain the desired electromagnetic torque of the generator. The actual electromagnetic torque of the generator is compared with the desired electromagnetic torque, and the comparison result is subjected to proportional-integral control through the torque control loop to obtain the desired direct-axis current of the generator. The actual electromagnetic torque is calculated based on the actual speed, the actual output current, and the actual output voltage. The actual direct-axis current of the generator is compared with the desired direct-axis current, and the comparison result is subjected to proportional-integral control through the first current control loop to obtain the first desired voltage.

5. The method according to claim 3, characterized in that, The second desired voltage is determined in the following manner: The actual output voltage of the generator is compared with the expected output voltage, and the comparison result is subjected to proportional-integral control through the voltage control loop to obtain the expected quadrature-axis current; The actual quadrature-axis current of the generator is compared with the desired quadrature-axis current, and the comparison result is subjected to proportional-integral control through the second current control loop to obtain the second desired voltage.

6. The method according to claim 1, characterized in that, The actual speed of the generator is determined in the following way: The actual rotational speed of the generator can be obtained by observing the flux linkage, or by installing a rotational speed measuring device on the generator.

7. The method according to claim 1, characterized in that, The generator and the energy storage converter are connected via a three-phase power transmission line. The actual output current and actual output voltage of the generator in a two-phase rotating coordinate system are determined by the following method: Obtain the three-phase output voltage and three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system; The electrical angle of the generator is calculated based on the actual rotational speed of the generator; Based on the electrical angle, the three-phase output voltage, and the three-phase output current, the actual output current and the actual output voltage are calculated.

8. The method according to claim 7, characterized in that, The input terminal of the energy storage converter includes a voltage sampling device and a current sampling device. The voltage sampling device is used to collect the three-phase output voltage, and the current sampling device is used to collect the three-phase output current.

9. A control system, characterized in that, The control system includes: dynamo; An energy storage converter is provided, with the output terminal of the generator connected to the input terminal of the energy storage converter. The output terminal of the energy storage converter is used to connect to at least one battery pack, and the generator is used to charge the battery pack. The controller of the energy storage converter is configured to execute the generator control method as described in any one of claims 1 to 8.

10. The system according to claim 9, characterized in that, The controller of the energy storage converter is configured as follows: The actual rotational speed of the generator can be obtained by observing the flux linkage of the generator, or by installing a rotational speed measuring device on the generator.

11. The system according to claim 9, characterized in that, The generator and the energy storage converter are connected via a three-phase power transmission line. The input terminal of the energy storage converter includes a voltage sampling device and a current sampling device. The voltage sampling device is used to collect the three-phase output voltage of the three-phase power transmission line in a three-phase stationary coordinate system, and the current sampling device is used to collect the three-phase output current of the three-phase power transmission line in a three-phase stationary coordinate system.

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