Flywheel energy storage motor control method and system

Abstract

This invention relates to the field of energy storage system control technology, and discloses a flywheel energy storage motor control method and system. The method includes: when the energy storage motor array outputs power, all energy storage units in the array operate in a discharge state; based on the discharge bus voltage command and the actual bus voltage, a DC voltage closed-loop PI controller calculates the total discharge current of the energy storage motor array; calculates the discharge current distribution coefficient for each individual energy storage motor; based on the total discharge current of the energy storage motor array and the discharge current distribution coefficient for each individual energy storage motor, calculates the discharge current command for each individual energy storage motor in the array; based on the discharge current command for each individual energy storage motor and the actual current value, a DC current closed-loop PI controller calculates the excitation current of each individual energy storage motor; the excitation current closed-loop PI controller outputs a voltage control command for each individual energy storage motor based on the excitation current of that individual energy storage motor; and the excitation controller controls each individual energy storage motor based on the voltage control command.

Description

Technical Field

[0001] This invention relates to the field of energy storage system control technology, and in particular to a flywheel energy storage motor control method and system. Background Technology

[0002] Clustered energy storage motors are characterized by large parameter dispersion, time-varying nature, and nonlinearity. This leads to energy coupling between different energy storage units, and the differences in unit parameters significantly impact the dynamic control characteristics of multiple energy storage units operating in parallel. Therefore, the parameter dispersion of clustered energy storage motors affects the stability of the entire energy storage system's output power and power quality.

[0003] Due to the parameter differences among different energy storage motor units, it is impossible for all parameters to be completely identical. If a control method based solely on equal power or equal torque is adopted, speed differences will gradually appear among the energy storage units during operation. When the slip between energy storage units is large, it will severely affect the overall output power of the energy storage motor array, resulting in a waste of energy storage array capacity. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a flywheel energy storage motor control method and system that can solve the problems in the prior art.

[0005] The technical solution of the present invention: a flywheel energy storage motor control method, wherein the method includes:

[0006] When the energy storage motor array outputs power, all energy storage units in the array operate in a discharge state, according to the discharge bus voltage command. and actual bus voltage The DC voltage closed-loop PI controller calculates the total discharge current of the energy storage motor array. ;

[0007] The first calculation module calculates the discharge current distribution coefficient for a single energy storage motor;

[0008] Based on the total discharge current of the energy storage motor array The second calculation module calculates the discharge current command for a single energy storage motor in the energy storage motor array, along with the discharge current distribution coefficient for each individual energy storage motor. ;

[0009] Based on the discharge current command of a single energy storage motor and actual current value DC current closed-loop PI controller calculates the excitation current of a single energy storage motor. ;

[0010] The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor;

[0011] The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

[0012] Preferably, the discharge current distribution coefficient of a single energy storage motor is calculated using the following formula:

[0013] ,

[0014] in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

[0015] Preferably, the discharge current command of a single energy storage motor in the energy storage motor array is calculated using the following formula. :

[0016] .

[0017] This invention also provides a flywheel energy storage motor control system, wherein the system includes a DC voltage closed-loop PI controller, a first calculation module, a second calculation module, a DC current closed-loop PI controller, an excitation current closed-loop PI controller, and an excitation controller. Each energy storage motor in the energy storage motor array is correspondingly equipped with the first calculation module, the second calculation module, the DC current closed-loop PI controller, the excitation current closed-loop PI controller, and the excitation controller, wherein:

[0018] When the energy storage motor array outputs power, all energy storage units in the array operate in a discharging state. The DC voltage closed-loop PI controller is used to control the discharge bus voltage according to the output power command. and actual bus voltage Calculate the total discharge current of the energy storage motor array. ;

[0019] The first calculation module is used to calculate the discharge current distribution coefficient of a single energy storage motor;

[0020] The second calculation module is used to calculate the total discharge current of the energy storage motor array. And the discharge current distribution coefficient of a single energy storage motor, to calculate the discharge current command of a single energy storage motor in the energy storage motor array. ;

[0021] A DC current closed-loop PI controller is used to control the discharge current of a single energy storage motor. and actual current value Calculate the excitation current of a single energy storage motor. ;

[0022] The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor;

[0023] The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

[0024] Preferably, the discharge current distribution coefficient of a single energy storage motor is calculated using the following formula:

[0025] ,

[0026] in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

[0027] Preferably, the discharge current command of a single energy storage motor in the energy storage motor array is calculated using the following formula. :

[0028] .

[0029] The above technical solution allows for the calculation of the total discharge current of the energy storage motor array and the distribution coefficient of the discharge current of a single energy storage motor. Based on these coefficients, the discharge current command for each individual energy storage motor in the array is calculated. Then, the excitation current of each individual energy storage motor is calculated based on its discharge current command. Finally, a voltage control command for each individual energy storage motor is output based on its excitation current, and control of the individual energy storage motor is achieved through an excitation controller. This invention, starting from the goal of ensuring that clustered energy storage motors discharge to their speed limits within the same timeframe and improving the energy utilization rate of the energy storage system, proposes the above technical solution. This avoids the impact of uneven discharge caused by differences in the parameters of individual energy storage motors, thus achieving balanced control of clustered energy storage. Attached Figure Description

[0030] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0031] Figure 1 A flowchart of a flywheel energy storage motor control method provided in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the cluster energy storage equalization control principle in an embodiment of the present invention. Detailed Implementation

[0033] Specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the following description, specific details are set forth for purposes of explanation and not limitation, in order to aid in a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced in other embodiments departing from these specific details.

[0034] It should be noted that, in order to avoid obscuring the invention with unnecessary details, only the device structure and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0035] like Figure 1 and 2 As shown, this embodiment of the invention provides a flywheel energy storage motor control method, wherein the method includes:

[0036] When the energy storage motor array outputs power, all energy storage units in the array operate in a discharge state, according to the discharge bus voltage command. and actual bus voltage The DC voltage closed-loop PI controller calculates the total discharge current of the energy storage motor array. ;

[0037] The first calculation module calculates the discharge current distribution coefficient for a single energy storage motor;

[0038] Based on the total discharge current of the energy storage motor array The second calculation module calculates the discharge current command for a single energy storage motor in the energy storage motor array, along with the discharge current distribution coefficient for each individual energy storage motor. ;

[0039] Based on the discharge current command of a single energy storage motor and actual current value DC current closed-loop PI controller calculates the excitation current of a single energy storage motor. ;

[0040] The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor;

[0041] The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

[0042] In other words, for each energy storage motor, its corresponding discharge current distribution coefficient can be calculated, and then the corresponding discharge current command and excitation current can be calculated based on the discharge current distribution coefficient to achieve corresponding control.

[0043] The above technical solution allows for the calculation of the total discharge current of the energy storage motor array and the distribution coefficient of the discharge current of a single energy storage motor. Based on these coefficients, the discharge current command for each individual energy storage motor in the array is calculated. Then, the excitation current of each individual energy storage motor is calculated based on its discharge current command. Finally, a voltage control command for each individual energy storage motor is output based on its excitation current, and control of the individual energy storage motor is achieved through an excitation controller. This invention, starting from the goal of ensuring that clustered energy storage motors discharge to their speed limits within the same timeframe and improving the energy utilization rate of the energy storage system, proposes the above technical solution. This avoids the impact of uneven discharge caused by differences in the parameters of individual energy storage motors, thus achieving balanced control of clustered energy storage.

[0044] According to one embodiment of the present invention, the discharge current distribution coefficient of a single energy storage motor is calculated by the following formula:

[0045] ,

[0046] in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

[0047] According to one embodiment of the present invention, the discharge current command of a single energy storage motor in an energy storage motor array is calculated by the following formula. :

[0048] .

[0049] This invention also provides a flywheel energy storage motor control system, wherein the system includes a DC voltage closed-loop PI controller, a first calculation module, a second calculation module, a DC current closed-loop PI controller, an excitation current closed-loop PI controller, and an excitation controller. Each energy storage motor in the energy storage motor array is correspondingly equipped with the first calculation module, the second calculation module, the DC current closed-loop PI controller, the excitation current closed-loop PI controller, and the excitation controller, wherein:

[0050] When the energy storage motor array outputs power, all energy storage units in the array operate in a discharging state. The DC voltage closed-loop PI controller is used to control the discharge bus voltage according to the output power command. and actual bus voltage Calculate the total discharge current of the energy storage motor array. ;

[0051] The first calculation module is used to calculate the discharge current distribution coefficient of a single energy storage motor;

[0052] The second calculation module is used to calculate the total discharge current of the energy storage motor array. And the discharge current distribution coefficient of a single energy storage motor, to calculate the discharge current command of a single energy storage motor in the energy storage motor array. ;

[0053] A DC current closed-loop PI controller is used to control the discharge current of a single energy storage motor. and actual current value Calculate the excitation current of a single energy storage motor. ;

[0054] The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor;

[0055] The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

[0056] The above technical solution allows for the calculation of the total discharge current of the energy storage motor array and the distribution coefficient of the discharge current of a single energy storage motor. Based on these coefficients, the discharge current command for each individual energy storage motor in the array is calculated. Then, the excitation current of each individual energy storage motor is calculated based on its discharge current command. Finally, a voltage control command for each individual energy storage motor is output based on its excitation current, and control of the individual energy storage motor is achieved through an excitation controller. This invention, starting from the goal of ensuring that clustered energy storage motors discharge to their speed limits within the same timeframe and improving the energy utilization rate of the energy storage system, proposes the above technical solution. This avoids the impact of uneven discharge caused by differences in the parameters of individual energy storage motors, thus achieving balanced control of clustered energy storage.

[0057] According to one embodiment of the present invention, the discharge current distribution coefficient of a single energy storage motor is calculated by the following formula:

[0058] ,

[0059] in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

[0060] According to one embodiment of the present invention, the discharge current command of a single energy storage motor in an energy storage motor array is calculated by the following formula. :

[0061] .

[0062] As can be seen from the above embodiments, the flywheel energy storage motor control method and system of the present invention have at least the following advantages:

[0063] (1) It overcomes the impact of differences in energy storage motor parameters, thereby enabling clustered energy storage motors to be charged to the target speed in the same amount of time;

[0064] (2) It enables clustered energy storage motors to discharge to the speed limit within the same time, significantly improving the parallel discharge time of energy storage motors and increasing the energy utilization rate of energy storage systems.

[0065] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0066] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0067] The apparatus and methods described above can be implemented in hardware or in combination with software. This invention relates to computer-readable programs that, when executed by a logic component, enable that logic component to implement the apparatus or constituent parts described above, or to implement the various methods or steps described above. This invention also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, etc.

[0068] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0069] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A flywheel energy storage motor control method, characterized in that, The method includes: When the energy storage motor array outputs power, all energy storage units in the array operate in a discharging state, according to the discharge bus voltage command. and actual bus voltage The DC voltage closed-loop PI controller calculates the total discharge current of the energy storage motor array. ; The first calculation module calculates the discharge current distribution coefficient for a single energy storage motor; Based on the total discharge current of the energy storage motor array The second calculation module calculates the discharge current command for a single energy storage motor in the energy storage motor array, along with the discharge current distribution coefficient for each individual energy storage motor. ; Based on the discharge current command of a single energy storage motor and actual current value DC current closed-loop PI controller calculates the excitation current of a single energy storage motor. ; The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor; The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

2. The method according to claim 1, characterized in that, The discharge current distribution coefficient for a single energy storage motor is calculated using the following formula: ， in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

3. The method according to claim 2, characterized in that, The discharge current command for a single energy storage motor in the energy storage motor array is calculated using the following formula. : 。 4. A flywheel energy storage motor control system, characterized in that, The system includes a DC voltage closed-loop PI controller, a first calculation module, a second calculation module, a DC current closed-loop PI controller, an excitation current closed-loop PI controller, and an excitation controller. Each energy storage motor in the energy storage motor array is correspondingly equipped with a first calculation module, a second calculation module, a DC current closed-loop PI controller, an excitation current closed-loop PI controller, and an excitation controller, wherein: When the energy storage motor array outputs power, all energy storage units in the array operate in a discharging state. The DC voltage closed-loop PI controller is used to control the discharge bus voltage according to the output power command. and actual bus voltage Calculate the total discharge current of the energy storage motor array. ; The first calculation module is used to calculate the discharge current distribution coefficient of a single energy storage motor; The second calculation module is used to calculate the total discharge current of the energy storage motor array. And the discharge current distribution coefficient of a single energy storage motor, to calculate the discharge current command of a single energy storage motor in the energy storage motor array. ; A DC current closed-loop PI controller is used to control the discharge current of a single energy storage motor. and actual current value Calculate the excitation current of a single energy storage motor. ; The excitation current closed-loop PI controller is based on the excitation current of a single energy storage motor. Output voltage control commands for a single energy storage motor; The excitation controller controls a single energy storage motor based on the voltage control command of the single energy storage motor.

5. The system according to claim 4, characterized in that, The discharge current distribution coefficient for a single energy storage motor is calculated using the following formula: ， in, This represents the discharge current distribution coefficient for energy storage motor N. This represents the current angular frequency of energy storage motor N. This represents the current angular frequency of energy storage motor i. This is the lower limit of the angular frequency at which the Nth energy storage motor can discharge. This is the lower limit of the angular frequency at which the i-th energy storage motor can discharge. Let N be the moment of inertia of the energy storage motor. Let be the moment of inertia of energy storage motor i.

6. The system according to claim 5, characterized in that, The discharge current command for a single energy storage motor in the energy storage motor array is calculated using the following formula. : 。

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