Rotating speed control method for compressed air energy storage compressor

Abstract

The invention relates to the technical field of compressed air energy storage simulation control, in particular to a compressed air energy storage compressor rotating speed control method which comprises the following steps: acquiring three-phase current of a motor stator by utilizing a preset motor model, and acquiring a target compressor rotating speed and a current compressor rotating speed by utilizing a preset compressor model; inputting the target compressor rotating speed, the current compressor rotating speed and the motor stator three-phase current into a preset rotating speed control module to obtain a three-phase voltage controlled by the motor so as to control the rotating speed of the compressor based on the three-phase voltage, and starting an anti-surge valve to control the compressor to operate when the surge margin of the compressor is smaller than a preset threshold value. And the compressor model, the motor model and the preset rotating speed control module are mutually connected. Therefore, the problems of low accuracy, low response speed and the like in a current compressor control method are solved, the target rotating speed of the compressor and the output capacity of the motor are fully considered, and the rotating speed is rapidly and effectively controlled.

Description

Technical Field

[0001] The present application relates to the technical field of compressed air energy storage simulation control, and in particular to a method for controlling the speed of a compressed air energy storage compressor. Background Art

[0002] In response to the macro-guidance of my country's dual-carbon target strategy, the development of new energy technologies is ushering in unprecedented opportunities and becoming a key driving force for building a green, low-carbon, and circular economic system. Given the intermittent and unstable characteristics of wind and solar power generation, the development of efficient large-scale energy storage solutions has become particularly critical. In this context, compressed air energy storage technology has become the focus of the research community due to its large storage capacity, long energy storage cycle, and high energy conversion efficiency. When designing and evaluating compressed air energy storage systems, it is extremely important to safely and effectively control the speed of the compressor. On the one hand, the speed of the compressor is directly related to core parameters such as compression ratio and efficiency, which affect the performance of the compressor; on the other hand, the speed of the compressor is closely related to the surge blocking phenomenon. Only by controlling the speed of the compressor can safe operation be guaranteed.

[0003] At present, there are mainly the following methods for the speed control of compressors: First, an open-loop control method based on a fixed control strategy to adjust the compressor speed. This method usually operates within the design parameter range of the compressor and does not rely on real-time feedback. The speed of the motor is controlled by a designed variable frequency drive to adjust the speed of the compressor. Although the control method is very simple and efficient and suitable for most application scenarios under stable working conditions, the compressor works under variable working conditions for a long time in the compressed air energy storage system. The complex operating state makes it difficult to use a fixed control strategy in advance to face the changing and complex working conditions. The second is a closed-loop control method based on the sensor detecting the real-time speed and comparing it with the expected speed. This method can monitor the current compressor speed in real time and compare it with the set speed, dynamically adjust the output of the motor, so that the speed remains at the set point. Compared with the open-loop control method, the accuracy and response speed of the control system are improved. However, for the variable working condition operation requirements of the compressed air energy storage compressor, the compressor's pressure ratio and mass flow rate will change with the change of the speed, so the compressor's power will also change. This linear control system is difficult to achieve efficient and stable control effects for a strong nonlinear change, so it is urgent to propose a more accurate and fast control method to control the compressor speed. Summary of the invention

[0004] The present application provides a method for controlling the speed of a compressed air energy storage compressor to solve the problems of low accuracy and slow response speed in current compressor control methods.

[0005] The first aspect of the present application provides a method for controlling the speed of a compressed air energy storage compressor, comprising the following steps: obtaining the three-phase current of a motor stator by using a preset motor model, and obtaining a target compressor speed and a current compressor speed by using a preset compressor model; inputting the target compressor speed, the current compressor speed and the three-phase current of the motor stator into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the speed of the compressor based on the three-phase voltage, and starting an anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold value, wherein the compressor model, the motor model and the preset speed control module are interconnected.

[0006] Optionally, the target compressor speed, the current compressor speed and the three-phase current of the motor stator are input into a preset speed control module to obtain the three-phase voltage controlled by the motor, including: using the preset speed control module to perform Clark transformation on the three-phase current of the motor stator to obtain the current in a two-phase orthogonal coordinate system, and performing Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and the q-axis current in the rotating coordinate system; calculating a first error value between the d-axis current and a preset d-axis current value and a second error value between the q-axis current and a preset q-axis current value, performing PI control on the first error value and the second error value respectively to obtain a d-axis voltage control amount and a q-axis voltage control amount; performing inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain the voltage in a two-phase orthogonal coordinate system; and performing space vector pulse width modulation SVPWM on the voltage in the two-phase orthogonal coordinate system to obtain the three-phase voltage controlled by the motor.

[0007] Optionally, before using the preset motor model to obtain the three-phase current of the motor stator, the method includes: obtaining the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature; based on the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature, using the mass conservation formula, the momentum conservation formula, and the energy conservation formula to establish a constraint relationship between the gas density, the outlet gas velocity, and the outlet gas temperature, and using a preset simulation platform to build the preset compressor model.

[0008] Optionally, the mass conservation formula is:

[0009]

[0010] The momentum conservation formula is:

[0011]

[0012] The energy conservation formula is:

[0013]

[0014] Where V is the volume of the compressor, q m,in is the compressor inlet mass flow rate, q m,out is the outlet mass flow rate of the compressor, c out is the outlet gas velocity, ρ out is the gas density at the compressor outlet, c in is the velocity of the inlet gas, p in is the inlet pressure, p out is the outlet pressure, A in is the inlet cross-sectional area of ​​the compressor, F is the impeller thrust, A out is the outlet cross-sectional area of ​​the compressor, h out is the specific enthalpy of the outlet gas, c p is the specific heat capacity, Rg is the gas constant, T out is the outlet gas temperature, W is the work done by the motor, τ is the time variable, and h is the specific enthalpy of the gas.

[0015] Optionally, when the surge margin of the compressor is less than a preset threshold, starting the anti-surge valve to control the operation of the compressor includes: determining the opening of the anti-surge valve based on a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula, so as to control the operation of the compressor based on the opening of the anti-surge valve, wherein the preset anti-surge valve opening control formula is:

[0016] x ASV =K p ·(SM target -SM)+K i ·∫(SM target -SM)dt;

[0017] Among them, K p and K i are proportional gain and integral gain respectively, SM target is the target surge margin, SM is the surge margin,

[0018] The preset anti-surge valve opening response formula is:

[0019]

[0020] Among them, τ valve is the valve time constant, x aSV,target The target opening.

[0021] The second aspect of the present application provides a compressed air energy storage compressor speed control system, including: an acquisition module, used to obtain the three-phase current of the motor stator using a preset motor model, and use a preset compressor model to obtain the target compressor speed and the current compressor speed; a control module, used to input the target compressor speed, the current compressor speed and the three-phase current of the motor stator into a preset speed control module, obtain the three-phase voltage controlled by the motor, control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold value, wherein the compressor model, the motor model and the preset speed control module are interconnected.

[0022] Optionally, the control module is also used to: use the preset speed control module to perform Clark transformation on the three-phase current of the motor stator to obtain the current in a two-phase orthogonal coordinate system, and perform Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and q-axis current in the rotating coordinate system; calculate the first error value between the d-axis current and the preset d-axis current value and the second error value between the q-axis current and the preset q-axis current value, perform PI control on the first error value and the second error value respectively to obtain the d-axis voltage control amount and the q-axis voltage control amount; perform inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain the voltage in a two-phase orthogonal coordinate system; perform space vector pulse width modulation SVPWM using the voltage in the two-phase orthogonal coordinate system to obtain the three-phase voltage controlled by the motor.

[0023] Optionally, before using the preset motor model to obtain the three-phase current of the motor stator, the acquisition module is also used to: obtain the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature; based on the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature, use the mass conservation formula, momentum conservation formula, and energy conservation formula to establish a constraint relationship between the gas density, the outlet gas velocity, and the outlet gas temperature, and use the preset simulation platform to build the preset compressor model.

[0024] Optionally, the mass conservation formula is:

[0025]

[0026] The momentum conservation formula is:

[0027]

[0028] The energy conservation formula is:

[0029]

[0030] Where V is the volume of the compressor, q m,in is the compressor inlet mass flow rate, q m,out is the outlet mass flow rate of the compressor, c out is the outlet gas velocity, ρ out is the gas density at the compressor outlet, c in is the velocity of the inlet gas, p in is the inlet pressure, p out is the outlet pressure, A in is the inlet cross-sectional area of ​​the compressor, F is the impeller thrust, A out is the outlet cross-sectional area of ​​the compressor, h out is the specific enthalpy of the outlet gas, c p is the specific heat capacity, Rg is the gas constant, T out is the outlet gas temperature, W is the work done by the motor, τ is the time variable, and h is the specific enthalpy of the gas.

[0031] Optionally, the control module is further used to: determine the opening of the anti-surge valve based on a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula, so as to control the operation of the compressor based on the opening of the anti-surge valve, wherein the preset anti-surge valve opening control formula is:

[0032] x ASV =K p ·(SM target -SM)+K i ·∫(SM target -SM)dt;

[0033] Among them, K p and K i are proportional gain and integral gain respectively, SM target is the target surge margin, SM is the surge margin,

[0034] The preset anti-surge valve opening response formula is:

[0035]

[0036] Among them, τ valve is the valve time constant, x ASV,target The target opening.

[0037] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the compressed air energy storage compressor speed control method as described in the above embodiment.

[0038] The fourth aspect of the present application provides a computer-readable storage medium on which a computer program is stored. The program is executed by a processor to implement the compressed air energy storage compressor speed control method as described in the above embodiment.

[0039] In the above implementation, the motor stator three-phase current is obtained by using a preset motor model, and the target compressor speed and the current compressor speed are obtained by using a preset compressor model. The target compressor speed, the current compressor speed and the motor stator three-phase current are input into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the compressor speed based on the three-phase voltage, and start the anti-surge valve to control the compressor operation when the surge margin of the compressor is less than a preset threshold. Thus, the problems of low accuracy and slow response speed in the current compressor control method are solved, and the target speed of the compressor and the output capacity of the motor are fully considered to control the speed quickly and effectively.

[0040] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0042] Figure 1 This is a flow chart of a method for controlling the speed of a compressed air energy storage compressor according to an embodiment of the present application;

[0043] Figure 2 is a schematic diagram of a compressor system according to an embodiment of the present application;

[0044] Figure 3 is a schematic diagram of a compressor speed control method according to an embodiment of the present application;

[0045] Figure 4 This is an example diagram of a compressed air energy storage compressor speed control system according to an embodiment of the present application;

[0046] Figure 5 Schematic diagram of the structure of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0047] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0048] The following describes the speed control method of the compressed air energy storage compressor of the embodiment of the present application with reference to the accompanying drawings. In view of the problems of low accuracy and slow response speed in the current compressor control method mentioned in the above background technology, the present application provides a compressed air energy storage compressor speed control method, in which the three-phase current of the motor stator is obtained by using a preset motor model, and the target compressor speed and the current compressor speed are obtained by using a preset compressor model, and the target compressor speed, the current compressor speed and the three-phase current of the motor stator are input into the preset speed control module to obtain the three-phase voltage controlled by the motor, so as to control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than the preset threshold. In this way, the problems of low accuracy and slow response speed in the current compressor control method are solved, and the target speed of the compressor and the output capacity of the motor are fully considered to control the speed quickly and effectively.

[0049] In modern advanced adiabatic compressed air energy storage systems, a common design is to use multi-stage compressors to gradually increase the pressure of the gas. Each compressor is driven by an independent motor, and these compressors are connected in sequence through pipelines to form a continuous compression process. In order to simplify the analysis, the following assumptions are made: First, the gas inside the compressor is regarded as uniformly distributed and modeled using the lumped parameter method; second, the compression process is regarded as an adiabatic process without heat exchange; third, the adiabatic compression efficiency of the compressor is set to 0.8; fourth, the force exerted by the compressor impeller on the gas during startup and stable operation remains constant; fifth, since the startup process is transient, it is assumed that the heat exchanger does not work during the startup phase, so the influence of the heat exchanger is not considered. Based on the above assumptions, the embodiment of the present application proposes a method for controlling the speed of a compressed air energy storage compressor.

[0050] Specifically, Figure 1 A schematic flow chart of a method for controlling the speed of a compressed air energy storage compressor provided in an embodiment of the present application.

[0051] like Figure 1 As shown, the compressed air energy storage compressor speed control method includes the following steps:

[0052] In step S101 , the three-phase current of the motor stator is obtained using a preset motor model, and the target compressor speed and the current compressor speed are obtained using a preset compressor model.

[0053] Optionally, in some embodiments, before using a preset motor model to obtain the three-phase current of the motor stator, the process includes: obtaining the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature; based on the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature, using the mass conservation formula, the momentum conservation formula, and the energy conservation formula to establish a constraint relationship between the gas density, the outlet gas velocity, and the outlet gas temperature, and using a preset compressor model using a preset simulation platform.

[0054] Optionally, in some embodiments, the mass conservation formula is:

[0055]

[0056] The formula for conservation of momentum is:

[0057]

[0058] The energy conservation formula is:

[0059]

[0060] Where V is the volume of the compressor, q m,in is the compressor inlet mass flow rate, q m,out is the outlet mass flow rate of the compressor, c out is the outlet gas velocity, ρ out is the gas density at the compressor outlet, c in is the velocity of the inlet gas, p in is the inlet pressure, p out is the outlet pressure, A in is the inlet cross-sectional area of ​​the compressor, F is the impeller thrust, A out is the outlet cross-sectional area of ​​the compressor, h out is the specific enthalpy of the outlet gas, c p is the specific heat capacity, Rg is the gas constant, T out is the outlet gas temperature, W is the work done by the motor, τ is the time variable, and h is the specific enthalpy of the gas.

[0061] First, it is necessary to determine the specific design parameters of the compressor and motor in the compression system, including the specifications of a single compressor and its corresponding motor. Since the compression system under study is generally a multi-stage design, that is, it contains two or more compressors and motors, such as Figure 2 As shown, one can start with a single level of compressor and motor and then apply the same approach to the design of other levels of compressors and motors.

[0062] The information obtained in the embodiment of the present application is recorded in the following form: the manufacturer and model of the compressor, the rated mass flow rate of the compressor is qm,0 , the rated speed of the compressor is n0, the rated pressure ratio of the compressor is ε0, the adiabatic efficiency of the compressor is η0, the volume of the compressor is V, and the inlet cross-sectional area of ​​the compressor is A in , the outlet cross-sectional area of ​​the compressor is A out , the rated voltage of the motor is V n , the stator resistance of the motor is R s , the stator leakage inductance of the motor is L ls , the rotor resistance of the motor is R r , the rotor leakage inductance of the motor is L lr , the mutual inductance of the motor is L m , the moment of inertia of the motor is I, and the number of pole pairs of the motor is P. It should be noted that the above are all design parameters, that is, the parameters fixed after the compressor and the motor leave the factory, which are different from the variables in the following text.

[0063] The compression system is further divided into two parts: the compressor and the motor, which are connected by speed and torque, such as Figure 3 As shown, the compressor calculates the torque from the current operating state and gives it to the motor as an input signal. The motor outputs the current speed to the compressor as an input signal to build a compression system. The compressor model construction method is as follows:

[0064] Select the gas density ρ inside the compressor and the outlet gas velocity c out , outlet gas temperature T out As state variables, other variables can be expressed by the above state variables. The specific relationship is shown in equations (1)-(3). In equation (3), W is given by the following equation:

[0065]

[0066]

[0067] Among them, the superscript · represents the converted variable, ε represents the pressure ratio, η represents the adiabatic compression efficiency, G represents the converted mass flow rate, N represents the converted speed, c1, c2, c3, c4 are intermediate parameters, where c4 is 0.8, q and m are 1.8. After obtaining all the information of the compression system, you can build a compressor model in simulink. Select the gas density ρ inside the compressor, the outlet gas velocity c out , outlet gas temperature T out As the state variable of the compressor, use the integral module in simulink and other operation symbols to build a compressor model. The specific method is to integrate the first-order differential of the state variable (that is, use the integration module ) to obtain the state variables, and then use the mass conservation formula, momentum conservation formula and energy conservation formula to obtain the constraint relationship. The specific formula is as shown in (1-3). At this point, the compressor model is completed.

[0068] Further, the motor model is constructed as follows: Open the library browser in Simulink, select the asynchronous machine SI units module, and set the rated voltage of the motor to V in the parameters according to the parameters obtained in the first step. n , the stator resistance of the motor is R s , the stator leakage inductance of the motor is L ls , the rotor resistance of the motor is R r , the rotor leakage inductance of the motor is L lr , the mutual inductance of the motor is L m , the moment of inertia of the motor is I, and the number of pole pairs of the motor is P. The model construction of the motor is now completed.

[0069] In step S102, the target compressor speed, the current compressor speed and the three-phase current of the motor stator are input into a preset speed control module to obtain a three-phase voltage controlled by the motor, so as to control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold value, wherein the compressor model, the motor model and the preset speed control module are interconnected.

[0070] Optionally, in some embodiments, the target compressor speed, the current compressor speed and the three-phase current of the motor stator are input into a preset speed control module to obtain the three-phase voltage controlled by the motor, including: using the preset speed control module to perform Clark transformation on the three-phase current of the motor stator to obtain the current in a two-phase orthogonal coordinate system, and performing Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and the q-axis current in the rotating coordinate system; calculating the first error value between the d-axis current and the preset d-axis current value and the second error value between the q-axis current and the preset q-axis current value, performing PI control on the first error value and the second error value respectively to obtain the d-axis voltage control amount and the q-axis voltage control amount; performing inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain the voltage in the two-phase orthogonal coordinate system; performing space vector pulse width modulation SVPWM on the voltage in the two-phase orthogonal coordinate system to obtain the three-phase voltage controlled by the motor.

[0071] It can be understood that the preset speed control module receives the target compressor speed n collected by the compressor model. ref , the current compressor speed n and the motor stator three-phase current I collected by the motor model abc , output three-phase voltage V for motor controlabc .

[0072] Specifically, the preset speed control module controls the three-phase current I abc Perform Clark transformation to obtain the current I in the two-phase orthogonal coordinate system α ,I β , and then perform Park transformation on the current in the two-phase orthogonal coordinate system to obtain the two-phase current in the rotating coordinate system, where the d-axis current is recorded as I d , q-axis current is recorded as I q , and set the preset d-axis current value I dref , for n ref Make a PI link to get the preset q-axis current value I qref , respectively with I d , I q The difference is recorded as the first error value and the second error value ΔI d ,ΔI q Finally, the first error value and the second error value ΔI d ,ΔI q Perform a PI link to obtain the d-axis voltage control quantity and the q-axis voltage control quantity V d ,V q , and finally use the obtained V d ,V q Perform space vector pulse width modulation SVPWM, output pulse signal to Universal Bridge, set the bridge arm of Universal Bridge to 3, the resistance to 1e-3, and finally set the output voltage V abc The output is given to the motor, which controls the speed of the compressor based on the three-phase voltage. The P parameters and I parameters of the three PI links are as follows:

[0073] Kp = initial proportional gain

[0074] Ki=initial integral gain

[0075] error=set value - actual value

[0076] error_prev = error at the previous moment

[0077] integral=integral term

[0078] dt = sampling time

[0079] dk = unity gain change

[0080] In each sampling period:

[0081] 1. Calculation error: error = setpoint - measured_value

[0082] 2. Update the integral term: integral = integral + error * dt

[0083] 3. Calculate the proportional part: proportional_output = Kp*error

[0084] 4. Calculate the integral part: integral_output = Ki*integral

[0085] 5. Calculate the total control output: control_output = proportional_output + integral_output

[0086] 6. Limit the control output to ensure it is within the allowable range

[0087] 7. Apply control output to the controlled system

[0088] 8. Update the last error: error_prev = error

[0089] At the end of each cycle:

[0090] 1. Evaluate the system's response and stability

[0091] 2. Adjust Kp and Ki based on the evaluation results:

[0092] -If the system responds too slowly, Kp=Kp+dk; Ki=Ki+dk

[0093] - If the system responds too quickly or oscillates, Kp = Kp-dk; Ki = Ki-dk

[0094] From then on, the PI parameters are automatically adjusted, and the speed control module based on adaptive control is completed.

[0095] The compressor model and the motor model constructed above are connected, wherein the torque required by the compressor is provided to the motor as a load, and the speed output by the motor is provided to the compressor, and then the target compressor speed n is set to ref , the current compressor speed n and the motor stator three-phase current I abc Input the speed control module of adaptive control, and convert the output V abc The three-phase stator input voltage is provided to the motor, and the motor controls the speed of the compressor based on the three-phase stator input voltage.

[0096] Optionally, in some embodiments, when the surge margin of the compressor is less than a preset threshold, the anti-surge valve is started to control the operation of the compressor, including: determining the opening of the anti-surge valve based on a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula, so as to control the operation of the compressor based on the opening of the anti-surge valve, wherein the preset anti-surge valve opening control formula is:

[0097] x ASV =K p ·(SM target -SM)+K i ·∫(SM target -SM)dt; (16)

[0098] Among them, k p and K i are proportional gain and integral gain respectively, SM target is the target surge margin, SM is the surge margin,

[0099] The preset anti-surge valve opening response formula is:

[0100]

[0101] Among them, τ valve is the valve time constant, x aSV,target The target opening.

[0102] In order to prevent surge from occurring during the operation of the compressor, an anti-surge control module is designed to dynamically adjust the operating state of the compressor so that it is always within the safe operating range. The specific implementation method is as follows:

[0103] By collecting the key operating parameters of the compressor in real time (such as inlet pressure P in , outlet pressure P out , mass flow and compressor speed n), calculate the pressure ratio at the current operating point According to the compressor characteristic curve, the surge boundary is identified and the surge margin SM is defined as follows:

[0104]

[0105] in, is the critical flow rate of surge boundary.

[0106] When the compressor surge margin SM < β thresoold When the surge margin is lower than the preset threshold, the anti-surge valve (Anti-Surge Valve ASV) is activated.

[0107] The opening of the anti-surge valve is determined by using a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula to control the operation of the compressor based on the opening of the anti-surge valve.

[0108] If the anti-surge valve is detected to be stuck or performing abnormally, an emergency shutdown signal will be triggered to protect the compressor and the system.

[0109] According to the compressed air energy storage compressor speed control method proposed in the embodiment of the present application, the motor stator three-phase current is obtained using a preset motor model, and the target compressor speed and the current compressor speed are obtained using a preset compressor model. The target compressor speed, the current compressor speed and the motor stator three-phase current are input into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the compressor speed based on the three-phase voltage, and start the anti-surge valve to control the compressor operation when the surge margin of the compressor is less than a preset threshold. In this way, the problems of low accuracy and slow response speed in the current compressor control method are solved, and the target speed of the compressor and the output capacity of the motor are fully considered to control the speed quickly and effectively. At the same time, the adaptive control can adjust the PI parameters for different compressors and motors, and can be applied to more and more complex situations.

[0110] Next, the compressed air energy storage compressor speed control system proposed in accordance with an embodiment of the present application will be described with reference to the accompanying drawings.

[0111] Figure 4 It is a block diagram of a compressed air energy storage compressor speed control system according to an embodiment of the present application.

[0112] like Figure 4 As shown, the compressed air energy storage compressor speed control system 10 includes: an acquisition module 100 and a control module 200 .

[0113] Among them, the acquisition module 100 is used to obtain the three-phase current of the motor stator using a preset motor model, and to obtain the target compressor speed and the current compressor speed using a preset compressor model; the control module 200 is used to input the target compressor speed, the current compressor speed and the three-phase current of the motor stator into a preset speed control module, and obtain the three-phase voltage controlled by the motor, so as to control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold value, wherein the compressor model, the motor model and the preset speed control module are interconnected.

[0114] Optionally, in some embodiments, the control module 200 is also used to: perform Clark transformation on the three-phase current of the motor stator using a preset speed control module to obtain the current in a two-phase orthogonal coordinate system, and perform Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and the q-axis current in the rotating coordinate system; calculate a first error value between the d-axis current and a preset d-axis current value and a second error value between the q-axis current and a preset q-axis current value, perform PI control on the first error value and the second error value respectively to obtain a d-axis voltage control amount and a q-axis voltage control amount; perform inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain the voltage in the two-phase orthogonal coordinate system; perform space vector pulse width modulation SVPWM using the voltage in the two-phase orthogonal coordinate system to obtain the three-phase voltage controlled by the motor.

[0115] Optionally, in some embodiments, before using a preset motor model to obtain the three-phase current of the motor stator, the acquisition module 100 is also used to: obtain the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature; based on the gas density inside the compressor, the outlet gas velocity, and the outlet gas temperature, use the mass conservation formula, the momentum conservation formula, and the energy conservation formula to establish a constraint relationship between the gas density, the outlet gas velocity, and the outlet gas temperature, and use a preset simulation platform to build a preset compressor model.

[0116] Optionally, in some embodiments, the mass conservation formula is:

[0117]

[0118] The formula for conservation of momentum is:

[0119]

[0120] The energy conservation formula is:

[0121]

[0122] Where V is the volume of the compressor, q m,in is the compressor inlet mass flow rate, q m,out is the outlet mass flow rate of the compressor, c out is the outlet gas velocity, ρ out is the gas density at the compressor outlet, c in is the velocity of the inlet gas, p in is the inlet pressure, p out is the outlet pressure, A in is the inlet cross-sectional area of ​​the compressor, F is the impeller thrust, A out is the outlet cross-sectional area of ​​the compressor, h out is the specific enthalpy of the outlet gas, cp is the specific heat capacity, Rg is the gas constant, T out is the outlet gas temperature, W is the work done by the motor, τ is the time variable, and h is the specific enthalpy of the gas.

[0123] Optionally, in some embodiments, the control module 200 is further used to: determine the opening of the anti-surge valve based on a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula, so as to control the operation of the compressor based on the opening of the anti-surge valve, wherein the preset anti-surge valve opening control formula is:

[0124] x ASV =K p ·(SM target -SM)+K i ·∫(SM target -SM)dt;

[0125] Among them, k p and K i are proportional gain and integral gain respectively, SM target is the target surge margin, SM is the surge margin,

[0126] The preset anti-surge valve opening response formula is:

[0127]

[0128] Among them, τ valve is the valve time constant, x ASV,target The target opening.

[0129] It should be noted that the aforementioned explanation of the embodiment of the compressed air energy storage compressor speed control method is also applicable to the compressed air energy storage compressor speed control system of this embodiment, and will not be repeated here.

[0130] According to the compressed air energy storage compressor speed control system proposed in the embodiment of the present application, the motor stator three-phase current is obtained using a preset motor model, and the target compressor speed and the current compressor speed are obtained using a preset compressor model. The target compressor speed, the current compressor speed and the motor stator three-phase current are input into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the compressor speed based on the three-phase voltage, and start the anti-surge valve to control the compressor operation when the surge margin of the compressor is less than a preset threshold. In this way, the problems of low accuracy and slow response speed in the current compressor control method are solved, and the target speed of the compressor and the output capacity of the motor are fully considered to control the speed quickly and effectively. At the same time, the adaptive control can adjust the PI parameters for different compressors and motors, and can be applied to more and more complex situations.

[0131] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0132] A memory 501 , a processor 502 , and a computer program stored in the memory 501 and executable on the processor 502 .

[0133] When the processor 502 executes the program, the compressed air energy storage compressor speed control method provided in the above embodiment is implemented.

[0134] Furthermore, the electronic device further comprises:

[0135] The communication interface 503 is used for communication between the memory 501 and the processor 502 .

[0136] The memory 501 is used to store computer programs that can be executed on the processor 502 .

[0137] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0138] If the memory 501, the processor 502 and the communication interface 503 are implemented independently, the communication interface 503, the memory 501 and the processor 502 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0139] Optionally, in a specific implementation, if the memory 501, the processor 502 and the communication interface 503 are integrated on a chip, the memory 501, the processor 502 and the communication interface 503 can communicate with each other through an internal interface.

[0140] The processor 502 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0141] An embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned compressed air energy storage compressor speed control method is implemented.

[0142] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0143] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0144] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0145] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable storage medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable storage medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable storage media include the following: an electrical connection with one or N wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable storage medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0146] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0147] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0148] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0149] The computer-readable storage medium mentioned above may be a read-only memory, a disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for controlling the speed of a compressed air energy storage compressor, characterized in that: The following steps are involved: Using a preset motor model to obtain the three-phase current of the motor stator, and using a preset compressor model to obtain the target compressor speed and the current compressor speed; The target compressor speed, the current compressor speed and the three-phase current of the motor stator are input into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold, wherein the compressor model, the motor model and the preset speed control module are interconnected.

2. The method according to claim 1, characterized in that The step of inputting the target compressor speed, the current compressor speed and the three-phase current of the motor stator into a preset speed control module to obtain the three-phase voltage controlled by the motor includes: Using the preset speed control module to perform Clark transformation on the three-phase current of the motor stator to obtain the current in a two-phase orthogonal coordinate system, and performing Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and the q-axis current in the rotating coordinate system; Calculating a first error value between a d-axis current and a preset d-axis current value and a second error value between a q-axis current and a preset q-axis current value, and performing PI control on the first error value and the second error value respectively to obtain a d-axis voltage control amount and a q-axis voltage control amount; Performing an inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain a voltage in a two-phase orthogonal coordinate system; The voltage in the two-phase orthogonal coordinate system is used to perform space vector pulse width modulation (SVPWM) to obtain the three-phase voltage for controlling the motor.

3. The method according to claim 1, characterized in that Before obtaining the three-phase current of the motor stator by using the preset motor model, the method includes: Obtain the gas density inside the compressor, the velocity of the outlet gas, and the temperature of the outlet gas; Based on the gas density inside the compressor, the velocity of the outlet gas, and the temperature of the outlet gas, the mass conservation formula, the momentum conservation formula, and the energy conservation formula are used to establish a constraint relationship between the gas density, the velocity of the outlet gas, and the temperature of the outlet gas, and the preset compressor model is built using a preset simulation platform.

4. The method according to claim 3, characterized in that The mass conservation formula is: The momentum conservation formula is: The energy conservation formula is: Where V is the volume of the compressor, q m,in is the compressor inlet mass flow rate, q m,out is the outlet mass flow rate of the compressor, c out is the outlet gas velocity, ρ out is the gas density at the compressor outlet, c in is the velocity of the inlet gas, p in is the inlet pressure, p out is the outlet pressure, A in is the inlet cross-sectional area of ​​the compressor, F is the impeller thrust, A out is the outlet cross-sectional area of ​​the compressor, h out is the specific enthalpy of the outlet gas, c p is the specific heat capacity, Rg is the gas constant, T out is the outlet gas temperature, W is the work done by the motor, τ is the time variable, and h is the specific enthalpy of the gas.

5. The method according to claim 1, characterized in that When the surge margin of the compressor is less than a preset threshold, starting the anti-surge valve to control the operation of the compressor includes: Based on a preset anti-surge valve opening control formula and a preset anti-surge valve opening response formula, the opening of the anti-surge valve is determined to control the operation of the compressor based on the opening of the anti-surge valve, wherein the preset anti-surge valve opening control formula is: x ASV =K p ·(SM target -SM)+K i ·∫(SM target -SM)dt; Among them, K p and K i are proportional gain and integral gain respectively, SM target is the target surge margin, SM is the surge margin, The preset anti-surge valve opening response formula is: Among them, τ valve is the valve time constant, x ASV,target The target opening.

6. A compressed air energy storage compressor speed control system, characterized in that: include: An acquisition module, used to acquire the three-phase current of the motor stator using a preset motor model, and to acquire the target compressor speed and the current compressor speed using a preset compressor model; A control module is used to input the target compressor speed, the current compressor speed and the three-phase current of the motor stator into a preset speed control module to obtain a three-phase voltage for motor control, so as to control the speed of the compressor based on the three-phase voltage, and start the anti-surge valve to control the operation of the compressor when the surge margin of the compressor is less than a preset threshold value, wherein the compressor model, the motor model and the preset speed control module are interconnected.

7. The system according to claim 6, characterized in that The control module is also used for: Using the preset speed control module to perform Clark transformation on the three-phase current of the motor stator to obtain the current in a two-phase orthogonal coordinate system, and performing Park transformation on the current in the two-phase orthogonal coordinate system to obtain the d-axis current and the q-axis current in the rotating coordinate system; Calculating a first error value between a d-axis current and a preset d-axis current value and a second error value between a q-axis current and a preset q-axis current value, and performing PI control on the first error value and the second error value respectively to obtain a d-axis voltage control amount and a q-axis voltage control amount; Performing an inverse Park transformation on the d-axis voltage control amount and the q-axis voltage control amount to obtain a voltage in a two-phase orthogonal coordinate system; The voltage in the two-phase orthogonal coordinate system is used to perform space vector pulse width modulation (SVPWM) to obtain the three-phase voltage for controlling the motor.

8. The system according to claim 6, characterized in that Before obtaining the three-phase current of the motor stator by using the preset motor model, the obtaining module is further used to: Obtain the gas density inside the compressor, the velocity of the outlet gas, and the temperature of the outlet gas; Based on the gas density inside the compressor, the velocity of the outlet gas, and the temperature of the outlet gas, the mass conservation formula, the momentum conservation formula, and the energy conservation formula are used to establish a constraint relationship between the gas density, the velocity of the outlet gas, and the temperature of the outlet gas, and the compressor model is built using a preset simulation platform.

9. An electronic device, characterized in that: It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the speed control method for a compressed air energy storage compressor as described in any one of claims 1 to 5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the compressed air energy storage compressor speed control method as described in any one of claims 1-5.

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