Variable structure control method, device and system for auxiliary power supply inverter of variable-voltage variable-frequency locomotive

Abstract

The invention provides a variable structure control method, device and system for an auxiliary power supply inverter of a variable-voltage variable-frequency locomotive. The control device comprises a frequency and voltage amplitude reference value generation module, a coordinate transformation module, a voltage loop controller, a source load instability detection module, a forward channel second gain module, a current feedforward gain module, a controller normalization gain module and a pulse width modulation module. According to the method, the problem of'source-load 'instability can be actively detected, and a multi-mode control solution which is variable in control structure and meets the'source-load' stable operation requirement is provided for multi-mode operation and complex and changeable load conditions of the railway rolling stock. According to the solution, seamless switching among multiple control modes is realized, and small signal stability analysis is combined, so that the stability and the reliability of the system in various operation states are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of railway locomotive and vehicle and mobile equipment manufacturing, and in particular to a variable structure control method, device and system for a variable voltage and variable frequency locomotive auxiliary power supply inverter. Background Art

[0002] Asynchronous motors are typical dynamic and nonlinear loads for power supply systems, and have a significant impact on the stability of power supply systems. For small power systems powered by general-purpose inverters, such as railway locomotive auxiliary power supply systems, asynchronous motors are prone to instability during low speed and starting, resulting in various system-level oscillation problems such as low-frequency envelope oscillation of system voltage.

[0003] At present, research has been conducted on the impact of asynchronous motor nonlinearity on power systems. The IEEE / CIGRE working group pointed out that the main cause of transient voltage instability is the motor stalling caused by the inability of the motor to accelerate after being disturbed, or the weakening of the transmission system connection strength caused by line over-limit or failure. A series of works by Milanovic and Hiskens showed that dynamic load characteristics such as motors have a significant impact on the low-frequency oscillation mode of the power system, especially the damping of inter-regional electromechanical oscillation mode. The reactive power demand of asynchronous motors during the operation of the power supply system and the positive feedback voltage instability phenomenon caused by it have also been widely discussed.

[0004] For small power systems powered by general-purpose inverters, such as railway locomotive auxiliary power supply systems, the source inverter capacity is limited, and the control function needs to take into account a variety of different load requirements. Generally, closed-loop motor drive control methods such as vector control cannot be selected, so that various asynchronous motor loads such as fans and pumps can only operate in variable voltage and variable frequency (VVVF) mode. In this working mode, the operation mode of the asynchronous motor has a wide frequency operating range and is prone to low-frequency instability. It is necessary to perform "source-to-source" instability detection and multi-mode targeted control. Summary of the invention

[0005] In view of this, the present invention provides a variable structure control method, device and system for a variable voltage and variable frequency locomotive auxiliary power supply inverter to solve at least one of the above-mentioned problems.

[0006] In order to achieve the above object, the present invention adopts the following scheme:

[0007] According to a first aspect of the present invention, a variable structure control device for an auxiliary power supply inverter of a variable voltage and variable frequency locomotive is provided, the control device comprising: a frequency and voltage amplitude reference value generation module, a coordinate transformation module, a voltage loop controller, a source load instability detection module, a forward channel second gain module, a current feedforward gain module, a controller normalized gain module and a pulse width modulation module, the coordinate transformation module is respectively connected to the frequency and voltage amplitude reference value generation module and the current feedforward gain module, the coordinate transformation module and the frequency and voltage amplitude reference value generation module are respectively connected to the voltage loop controller and the source load instability detection module through a comparator, the source load instability detection module is also respectively connected to the forward channel second gain module and the current feedforward gain module, the voltage loop controller is connected to the forward channel second gain module, the forward channel second gain module and the current feedforward gain module are connected to the controller normalized gain module through a comparator, and the pulse width modulation module is connected to the controller normalized gain module.

[0008] As an embodiment of the present invention, the frequency and voltage amplitude reference value generation module is used to generate a power supply bus frequency reference value and a voltage reference value to control loop operation; the coordinate transformation module is used to process the voltage and current signals obtained by feedback based on the power supply bus frequency reference value, and the direct-axis and quadrature-axis voltages obtained after processing are subtracted from the voltage reference value to obtain difference information, which is then input into the voltage loop controller and the source-load instability detection module; the voltage loop controller is used to implement feedback control-based regulation of the bus voltage, and its output is secondary regulated via the forward channel second gain module; the source-load instability detection module is used to determine whether the railway locomotive auxiliary power supply system has a source-load instability phenomenon based on the difference information, and to assist the forward channel second gain module and the current feedforward gain module in selecting real-time parameters; the current feedforward gain module is used to adjust the overall control structure of the system through gain parameters and setting modes, thereby achieving seamless switching between two control modes; the controller normalization gain module is used to perform secondary calibration on the control output; the pulse width modulation module is used to generate a pulse width modulation signal based on the output of the controller normalization gain module to control the semiconductor power module.

[0009] As an embodiment of the present invention, the above-mentioned source load instability detection module includes a second-order bandpass filter, a mathematical calculation unit and a threshold determination unit, and the mathematical calculation unit is connected to the second-order bandpass filter and the threshold determination unit respectively.

[0010] As an embodiment of the present invention, the second-order bandpass filter is used to filter the difference between the processed feedback amount and the given values ​​of the direct-axis and quadrature-axis voltages; the mathematical calculation unit is used to perform mathematical calculations on the filtered difference according to the following formula:

[0011]

[0012] In the above formula, εd and εq are the differences between the processed feedback and the given values ​​of the direct-axis and quadrature-axis voltages, respectively, and E is the overall amplitude of the medium- and high-frequency control residuals;

[0013] The threshold determination unit is used to compare E with a preset threshold. If E is greater than the preset threshold for n consecutive calculation cycles, it is determined to be a source-load instability phenomenon.

[0014] As an embodiment of the present invention, the passband frequency parameters of the second-order bandpass filter are determined by an offline analysis process.

[0015] As an embodiment of the present invention, the above-mentioned offline analysis process includes the following steps:

[0016] Step 1: Input asynchronous motor load parameters;

[0017] Step 2, based on the asynchronous motor load parameter, the input impedance of the asynchronous motor is calculated every 5 Hz in the interval [0, 60 Hz];

[0018] Step 3: Input the converter control parameters and electrical parameters;

[0019] Step 4, determine the variable of interest and the range of the variable of interest;

[0020] Step 5, respectively calculating the output impedance of the converter under the value of the concerned parameter according to the preset concerned parameter step size;

[0021] Step 6: Calculate the loop gain based on the input impedance and the output impedance, and use the Nyquist stability criterion to analyze whether the system is small signal stable;

[0022] Step 7, record the data matrix;

[0023] Step 8: Determine whether all variables of interest have been analyzed. If not, return to step 3 to analyze the next variable. If yes, derive a data matrix and obtain the passband frequency parameters of the second-order bandpass filter based on the data matrix.

[0024] As an embodiment of the present invention, the above-mentioned forward channel second gain module and the current feedforward gain module have a control structure and variable parameter properties, and the control mode of the forward channel second gain module and the current feedforward gain module includes one of a proportional mode and a proportional integral mode, and the controller mode is determined by the switching process requirements.

[0025] As an embodiment of the present invention, the frequency and voltage amplitude reference value generation module has three modes: droop, constant voltage and constant frequency, and variable voltage and variable frequency.

[0026] As an embodiment of the present invention, the controller normalized gain module is a proportional gain, and the preferred gain value is the inverse of the rated voltage of the system DC bus.

[0027] According to a second aspect of the present invention, there is provided a variable structure control system for a transformer-frequency locomotive auxiliary power supply inverter, the control system comprising: a control device, a semiconductor power module, a filter and a load bus port as described above, the semiconductor power module is connected to the filter, the control device is respectively connected to the semiconductor power module and the filter, and the load bus port is connected to the filter.

[0028] According to a third aspect of the present invention, there is provided a variable structure control method for a variable voltage and variable frequency locomotive auxiliary power supply inverter, the method comprising the following steps: a frequency and voltage amplitude reference value generation module generates a power supply bus frequency reference value and a voltage reference value; a coordinate transformation module processes the voltage and current signals obtained by feedback based on the power supply bus frequency reference value; a direct-axis and quadrature-axis voltage obtained after processing is subtracted from the voltage reference value to obtain difference information; a voltage loop controller implements feedback control-based regulation on the bus voltage based on the difference information to obtain a regulation signal; a forward channel second gain module performs secondary regulation on the regulation signal to control the current; a source-load instability detection module determines whether a source-load instability phenomenon occurs in the auxiliary power supply system of a railway locomotive based on the difference information; a current feedforward gain module adjusts the overall control structure of the system through gain parameters and setting modes, thereby realizing seamless switching between the two control modes; a controller normalization gain module performs secondary calibration on the control output; and a pulse width modulation signal is generated based on the output of the controller normalization gain module to control a semiconductor power module.

[0029] According to a fourth aspect of the present invention, there is provided an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the computer program.

[0030] According to a fifth aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above method when executed by a processor.

[0031] According to a sixth aspect of the present invention, there is provided a computer program product, comprising a computer program / instructions, which implement the steps of the above method when executed by a processor.

[0032] It can be seen from the above technical solutions that the variable voltage and frequency locomotive auxiliary power supply inverter variable structure control method, device and system provided by the present application can actively detect the "source-load" instability problem, and provide a multi-mode control solution with a variable control structure and meeting the "source-load" stable operation requirements for railway locomotive vehicles and complex and variable load conditions. This solution significantly improves the stability and reliability of the system under various operating conditions by achieving seamless switching between multiple control modes and combining small signal stability analysis. It not only solves the stability problems existing in the prior art, but also improves the adaptability and flexibility of the system, providing a strong guarantee for the safe and stable operation of the railway locomotive auxiliary power supply system, but also provides new ideas and methods for the control of similar small power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0034] Figure 1 It is a structural schematic diagram of a variable voltage and frequency locomotive auxiliary power supply inverter variable structure control system provided in an embodiment of the present application;

[0035] Figure 2 It is a schematic diagram of the structure of a traditional cascade multi-loop control device;

[0036] Figure 3 It is a schematic diagram of the structure of a variable voltage and frequency locomotive auxiliary power supply inverter variable structure control device provided in an embodiment of the present application;

[0037] Figure 4 It is a structural schematic diagram of a source-load instability detection module provided in an embodiment of the present application;

[0038] Figure 5 This is a schematic diagram of an offline analysis process provided by an embodiment of the present application;

[0039] Figure 6 is a schematic diagram of a controller mode switching process provided by an embodiment of the present application;

[0040] Figure 7 It is a flow chart of a variable structure control method of a variable voltage and variable frequency locomotive auxiliary power supply inverter provided in an embodiment of the present application;

[0041] Figure 8 It is a schematic block diagram of the system structure of the electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0043] like Figure 1 Shown is a structural schematic diagram of a variable voltage and frequency locomotive auxiliary power supply inverter variable structure control system provided in an embodiment of the present application, the control system includes: a semiconductor power module 1, a filter 2, a load bus port 3 and a control device 4, wherein the semiconductor power module 1 is connected to the filter 2, the control device 4 is respectively connected to the semiconductor power module 1 and the filter 2, and the load bus port 3 is connected to the filter 2.

[0044] The semiconductor power module 1 is the core power conversion unit of the system, which is usually composed of power semiconductor devices such as IGBT (insulated gate bipolar transistor) or MOSFET (metal oxide semiconductor field effect transistor), which determines the power processing capacity and efficiency of the system. The filter 2 can filter the high-frequency noise and harmonics in the power signal, thereby improving the quality of the output voltage and making it closer to the ideal sinusoidal waveform. It is usually composed of inductance and capacitance to form an LC filter circuit. The load bus port 3 is used as the output interface of the system to connect various auxiliary equipment loads and provide a stable power supply for the auxiliary equipment on the locomotive (such as air conditioning, lighting, control system, etc.). It needs to maintain a stable voltage and frequency to meet the needs of different loads. The control device 4 is responsible for controlling and coordinating the work of other components. In this embodiment, it can generate a control signal to drive the semiconductor power module 1, and can also realize "source-load" instability detection, and can also execute a variable structure control algorithm to switch different control modes as needed.

[0045] The above components work together to form a complete control system: the control device 4 generates appropriate control signals according to system requirements and operating status; these signals drive the semiconductor power module 1 to convert power; the converted power passes through the filter 2 to remove unnecessary high-frequency components; the filtered power is finally supplied to various auxiliary devices through the load bus port 3. At the same time, the control device 4 continuously monitors the system status, including output voltage, current and other parameters, and makes necessary adjustments to keep the system running stably. This structural design enables the system to adapt to the complex and changeable operating environment and load conditions of railway locomotives, and ensure the stability and reliability of the auxiliary power supply system. The variable structure control method and "source-load" instability detection function of the control device further improve the system's ability to cope with various working conditions.

[0046] The control device 4 is further described below. Figure 2The figure shows a schematic diagram of the structure of a conventional cascade multi-loop control device, which includes a coordinate transformation module 5, a frequency and voltage amplitude reference value generation module 6, a voltage loop controller 7, a current loop controller 8 and a pulse width modulation module 9. The coordinate transformation module 5 is connected to the frequency and voltage amplitude reference value generation module 6 respectively, the coordinate transformation module 5 and the frequency and voltage amplitude reference value generation module 6 are connected to the voltage loop controller 7 respectively through a comparator, the outputs of the voltage loop controller 7 and the coordinate transformation module 5 are connected to the current loop controller 8 through a comparator, and the pulse width modulation module 9 is connected to the current loop controller 8.

[0047] The present invention realizes seamless switching among multiple control modes, including single voltage closed loop, voltage closed loop with current feedforward, voltage and current dual closed loop, etc., by splitting and restructuring the traditional cascade multi-loop control device. Figure 3 The structure diagram of the variable voltage and frequency locomotive auxiliary power supply inverter variable structure control device provided by the embodiment of the present application is shown as follows: Figure 3 It can be seen that the control device includes: a frequency and voltage amplitude reference value generation module 6, a coordinate transformation module 5, a voltage loop controller 7, a source-load instability detection module 8, a forward channel second gain module 10, a current feedforward gain module 11, a controller normalized gain module 12 and a pulse width modulation module 9.

[0048] Among them, the coordinate transformation module 5 is respectively connected to the frequency and voltage amplitude reference value generation module 6 and the current feedforward gain module 11, the coordinate transformation module 5 and the frequency and voltage amplitude reference value generation module 6 are respectively connected to the voltage loop controller 7 and the source load instability detection module 8 through a comparator, the source load instability detection module 8 is also respectively connected to the forward channel second gain module 10 and the current feedforward gain module 11, the voltage loop controller 7 is connected to the forward channel second gain module 10, the forward channel second gain module 10 and the current feedforward gain module 11 are connected to the controller normalized gain module 12 through a comparator, and the pulse width modulation module 9 is connected to the controller normalized gain module 12.

[0049] The frequency and voltage amplitude reference value generation module 6 is used to generate the power supply bus frequency reference value and voltage reference value to control the operation of the loop. The frequency and voltage amplitude reference value generation module 6 is the starting point of the control system and is responsible for generating the basic reference values ​​required for the operation of the entire system. These reference values ​​are used to control the operation of the loop.

[0050] Preferably, the frequency and voltage amplitude reference value generation module 6 has three modes: droop, constant voltage and frequency, and variable voltage and frequency. When multiple auxiliary power supplies work in parallel, the droop mode can be used to achieve automatic load distribution; it can be used when the locomotive is in a stable operating state and needs to provide a stable power supply for sensitive equipment; it can be used in locomotive start-up, acceleration, or other scenarios where the motor speed needs to be adjusted to optimize energy efficiency. The frequency and voltage amplitude reference value generation module 6 can switch between these three modes, so that the system can adapt to different operating conditions and load requirements, improving the flexibility and efficiency of the system. This multi-mode operation is an important feature of the invention, which helps to improve the overall performance and adaptability of the railway locomotive auxiliary power supply system.

[0051] The coordinate transformation module 5 is used to process the voltage and current signals obtained by feedback based on the power supply bus frequency reference value. The direct-axis and quadrature-axis voltages obtained after processing are subtracted from the voltage reference value to obtain difference information which is input into the voltage loop controller 7 and the source-load instability detection module 8, while the direct-axis and quadrature-axis currents obtained after processing are input into the current feedforward gain module 11.

[0052] The voltage loop controller 7 is used to implement feedback control-based regulation of the bus voltage, and its output is secondary regulated via the forward channel second gain module 10. The voltage loop controller 7 is one of the main controllers of the system and is responsible for maintaining the stability of the bus voltage. Preferably, the voltage loop controller 7 is a PI (proportional-integral) controller.

[0053] The source load instability detection module 8 is used to determine whether the railway locomotive auxiliary power supply system has a source load instability phenomenon based on the difference between the processed feedback amount and the direct axis and quadrature axis voltage given values, and is used to assist the forward channel second gain module and the current feedforward gain module in selecting real-time parameters. This is a key innovation of the present invention, which is used to monitor and prevent system instability.

[0054] Preferably, Figure 4 The figure shows a structural schematic diagram of a source load instability detection module provided in an embodiment of the present application. The source load instability detection module includes a second-order bandpass filter 18, a mathematical calculation unit 19 and a threshold judgment unit 20. The mathematical calculation unit 19 is connected to the second-order bandpass filter 18 and the threshold judgment unit 20 respectively.

[0055] The second-order bandpass filter 18 is used to filter the difference between the processed feedback amount and the given values ​​of the direct-axis and quadrature-axis voltages.

[0056] Preferably, the passband frequency parameters of the second-order bandpass filter 18 can be determined by an offline analysis process. Figure 5 The figure shows a schematic diagram of an offline analysis process provided by an embodiment of the present application, which includes the following steps:

[0057] Step 1: Input asynchronous motor load parameters;

[0058] Step 2, based on the asynchronous motor load parameter, the input impedance of the asynchronous motor is calculated every 5 Hz in the interval [0, 60 Hz];

[0059] Step 3: Input the converter control parameters and electrical parameters;

[0060] Step 4, determine the variable of interest and the range of the variable of interest;

[0061] Step 5, respectively calculating the output impedance of the converter under the value of the concerned parameter according to the preset concerned parameter step size;

[0062] Step 6: Calculate the loop gain based on the input impedance and the output impedance, and use the Nyquist stability criterion to analyze whether the system is small signal stable;

[0063] Step 7, record the data matrix;

[0064] Step 8: Determine whether all variables of interest have been analyzed. If not, return to step 3 to analyze the next variable. If yes, derive a data matrix and obtain the passband frequency parameters of the second-order bandpass filter based on the data matrix.

[0065] The mathematical calculation unit 19 is used to perform mathematical calculation on the filtered difference according to the following formula:

[0066]

[0067] In the above formula, εd and εq are the differences between the processed feedback and the given values ​​of the direct-axis and quadrature-axis voltages, respectively, and E is the overall amplitude of the medium and high-frequency control residual.

[0068] The threshold determination unit 20 is used to compare E with a preset threshold. If E is greater than the preset threshold for n consecutive calculation cycles, it is determined to be a source load instability phenomenon. At this time, the threshold determination unit 20 can output 1, otherwise it outputs 0.

[0069] The current feedforward gain module 11 is used to adjust the overall control structure of the system through gain parameters and setting modes, so as to achieve seamless switching between two control modes.

[0070] The controller normalization gain module 12 is used to perform secondary calibration on the control output.

[0071] Preferably, the controller normalized gain module 12 is a proportional gain, and its preferred gain value is the inverse of the rated voltage of the system DC bus.

[0072] The pulse width modulation module 9 is used to generate a pulse width modulation signal based on the output of the controller normalized gain module 12 to control the semiconductor power module.

[0073] Preferably, the forward channel second gain module 10 and the current feedforward gain module 11 have control structures and variable parameter properties, and the control modes of the forward channel second gain module 10 and the current feedforward gain module 11 include one of a proportional mode and a proportional integral mode, and the controller mode is determined by the switching process requirements. For details, see Figure 6 ,Depend on Figure 6 It can be seen that the control system switches in sequence between the four states of State-1 to State-4, where the initial state is State-3, and the control transfer functions of controller 14 and controller 15 are represented by G14(s) and G15(s) respectively. When the aforementioned test detection module 8 detects the system instability phenomenon, the instability flag position is high, the system switches from State-3 to the switching state State-4, and the controller parameters change. For details, refer to the transfer function shown in the figure, where (P2, I2) are the initial parameters of the controller, (P1, 0) are the variable structure parameters of the controller, P2~P1 means that the control parameters are linearly transformed from P2 to P1; P1~P2 means that the controller parameters are linearly changed from P1 to P2.

[0074] From the above, it can be seen that the variable voltage and frequency locomotive auxiliary power supply inverter variable structure control device and system provided by the present application can actively detect the "source-load" instability problem, and provide a multi-mode control solution with a variable control structure and meeting the "source-load" stable operation requirements for the multi-mode operation and complex and variable load conditions of railway locomotive vehicles. This solution significantly improves the stability and reliability of the system under various operating conditions by realizing seamless switching between multiple control modes and combining small signal stability analysis. It not only solves the stability problems existing in the prior art, but also improves the adaptability and flexibility of the system, providing a strong guarantee for the safe and stable operation of the railway locomotive auxiliary power supply system, but also provides new ideas and methods for the control of similar small power systems.

[0075] like Figure 7 The figure is a flow chart of a variable structure control method of a variable voltage and variable frequency locomotive auxiliary power supply inverter provided by an embodiment of the present application, the method comprising the following steps:

[0076] Step S701: The frequency and voltage amplitude reference value generation module generates a power supply bus frequency reference value and a voltage reference value.

[0077] Step S702: the coordinate transformation module processes the voltage and current signals obtained by feedback based on the power supply bus frequency reference value.

[0078] Step S703: Subtract the direct-axis and quadrature-axis voltages obtained after processing from the voltage reference value to obtain difference information.

[0079] Step S704: the voltage loop controller adjusts the bus voltage based on feedback control based on the difference information to obtain an adjustment signal.

[0080] Step S705: the second gain module of the forward channel performs secondary regulation on the regulation signal to control the current.

[0081] Step S706: The source-load instability detection module determines whether the railway locomotive auxiliary power supply system has a source-load instability phenomenon based on the difference information.

[0082] Step S707: the current feedforward gain module adjusts the overall control structure of the system through the gain parameters and the setting mode, thereby achieving seamless switching between the two control modes.

[0083] Step S708: The controller normalization gain module performs secondary calibration on the control output.

[0084] Step S709: Generate a pulse width modulation signal based on the output of the normalized gain module of the controller to control the semiconductor power module.

[0085] For a detailed description of the above method, please refer to the corresponding description of the above control device, which will not be further described here.

[0086] From the above, it can be seen that the variable structure control method of the variable voltage and variable frequency locomotive auxiliary power supply inverter provided by the present application can actively detect the "source-load" instability problem, and provide a multi-mode control solution with a variable control structure and meeting the "source-load" stable operation requirements for the multi-mode operation and complex and variable load conditions of railway locomotive vehicles. This solution significantly improves the stability and reliability of the system under various operating conditions by realizing seamless switching between multiple control modes and combining small signal stability analysis. It not only solves the stability problems existing in the prior art, but also improves the adaptability and flexibility of the system, providing a strong guarantee for the safe and stable operation of the railway locomotive auxiliary power supply system, but also provides new ideas and methods for the control of similar small power systems.

[0087] An embodiment of the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the above method is implemented when the processor executes the program.

[0088] An embodiment of the present invention further provides a computer program product, including a computer program / instruction, which implements the steps of the above method when the computer program / instruction is executed by a processor.

[0089] An embodiment of the present invention further provides a computer-readable storage medium, which stores a computer program for executing the above method.

[0090] like Figure 8 As shown, the electronic device 600 may further include: a communication module 110, an input unit 120, an audio processor 130, a display 160, and a power supply 170. It is worth noting that the electronic device 600 does not necessarily have to include Figure 8 In addition, the electronic device 600 may also include Figure 8 For components not shown, reference may be made to the prior art.

[0091] like Figure 8 As shown, the central processor 100 is sometimes also referred to as a controller or an operation control, and may include a microprocessor or other processor devices and / or logic devices. The central processor 100 receives inputs and controls the operations of various components of the electronic device 600.

[0092] The memory 140 may be, for example, one or more of a cache, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory or other suitable devices. The above-mentioned information related to the failure may be stored, and a program for executing the relevant information may also be stored. The CPU 100 may execute the program stored in the memory 140 to implement information storage or processing.

[0093] The input unit 120 provides input to the CPU 100. The input unit 120 is, for example, a key or a touch input device. The power supply 170 is used to provide power to the electronic device 600. The display 160 is used to display display objects such as images and text. The display may be, for example, an LCD display, but is not limited thereto.

[0094] The memory 140 may be a solid-state memory, such as a read-only memory (ROM), a random access memory (RAM), a SIM card, etc. It may also be a memory that saves information even when the power is off, can be selectively erased, and is provided with more data, examples of which are sometimes referred to as EPROMs, etc. The memory 140 may also be some other type of device. The memory 140 includes a buffer memory 141 (sometimes referred to as a buffer). The memory 140 may include an application / function storage unit 142, which is used to store application programs and function programs or processes for executing the operation of the electronic device 600 through the central processor 100.

[0095] The memory 140 may also include a data storage unit 143 for storing data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 144 of the memory 140 may include various drivers for communication functions of the electronic device and / or for executing other functions of the electronic device (such as messaging applications, address book applications, etc.).

[0096] The communication module 110 is a transmitter / receiver that transmits and receives signals via the antenna 111. The communication module (transmitter / receiver) is coupled to the central processor 100 to provide input signals and receive output signals, which may be the same as the case of a conventional mobile communication terminal.

[0097] Based on different communication technologies, multiple communication modules 110 may be provided in the same electronic device, such as a cellular network module, a Bluetooth module and / or a wireless local area network module, etc. The communication module (transmitter / receiver) is also coupled to a speaker 131 and a microphone 132 via an audio processor 130 to provide an audio output via the speaker 131 and receive an audio input from the microphone 132, thereby realizing a common telecommunication function. The audio processor 130 may include any suitable buffer, decoder, amplifier, etc. In addition, the audio processor 130 is also coupled to the central processor 100, so that recording can be performed on the local machine through the microphone 132, and the sound stored on the local machine can be played through the speaker 131.

[0098] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0099] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0100] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0102] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive, characterized in that: The control device includes: a frequency and voltage amplitude reference value generation module, a coordinate transformation module, a voltage loop controller, a source load instability detection module, a forward channel second gain module, a current feedforward gain module, a controller normalized gain module and a pulse width modulation module. The coordinate transformation module is respectively connected to the frequency and voltage amplitude reference value generation module and the current feedforward gain module. The coordinate transformation module and the frequency and voltage amplitude reference value generation module are respectively connected to the voltage loop controller and the source load instability detection module through a comparator. The source load instability detection module is also respectively connected to the forward channel second gain module and the current feedforward gain module. The voltage loop controller is connected to the forward channel second gain module. The forward channel second gain module and the current feedforward gain module are connected to the controller normalized gain module through a comparator. The pulse width modulation module is connected to the controller normalized gain module.

2. The variable voltage and frequency locomotive auxiliary power inverter variable structure control device according to claim 1, characterized in that: The frequency and voltage amplitude reference value generation module is used to generate a power supply bus frequency reference value and a voltage reference value to control loop operation; The coordinate transformation module is used to process the voltage and current signals obtained by feedback based on the power supply bus frequency reference value, and the direct-axis and quadrature-axis voltages obtained after the processing are subtracted from the voltage reference value to obtain difference information, which is then input into the voltage loop controller and the source-load instability detection module; The voltage loop controller is used to implement feedback control-based regulation on the bus voltage, and its output is secondarily regulated via the second gain module of the forward channel; The source-load instability detection module is used to determine whether the railway locomotive auxiliary power supply system has a source-load instability phenomenon based on the difference information, and is used to assist the forward channel second gain module and the current feedforward gain module in selecting real-time parameters; The current feedforward gain module is used to adjust the overall control structure of the system through gain parameters and setting modes, so as to achieve seamless switching between the two control modes; The controller normalization gain module is used to perform secondary calibration on the control output; The pulse width modulation module is used to generate a pulse width modulation signal based on the output of the controller normalized gain module to control the semiconductor power module.

3. The variable voltage and frequency locomotive auxiliary power inverter variable structure control device according to claim 2, characterized in that: The source load instability detection module includes a second-order bandpass filter, a mathematical calculation unit and a threshold determination unit, and the mathematical calculation unit is connected to the second-order bandpass filter and the threshold determination unit respectively.

4. The variable voltage and frequency locomotive auxiliary power inverter variable structure control device according to claim 3, characterized in that: The second-order bandpass filter is used to filter the difference between the processed feedback amount and the given values ​​of the direct-axis and quadrature-axis voltages; The mathematical calculation unit is used to perform mathematical calculation on the filtered difference according to the following formula: In the above formula, εd and εq are the differences between the processed feedback and the given values ​​of the direct-axis and quadrature-axis voltages, respectively, and E is the overall amplitude of the medium- and high-frequency control residuals; The threshold determination unit is used to compare E with a preset threshold. If E is greater than the preset threshold for n consecutive calculation cycles, it is determined to be a source-load instability phenomenon.

5. The variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive according to claim 4, characterized in that: The passband frequency parameters of the second-order bandpass filter are determined by an off-line analysis process.

6. The variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive according to claim 5, characterized in that: The offline analysis process includes the following steps: Step 1: Input asynchronous motor load parameters; Step 2, based on the asynchronous motor load parameter, the input impedance of the asynchronous motor is calculated every 5 Hz in the interval [0, 60 Hz]; Step 3: Input the converter control parameters and electrical parameters; Step 4, determine the variable of interest and the range of the variable of interest; Step 5, respectively calculating the output impedance of the converter under the value of the concerned parameter according to the preset concerned parameter step size; Step 6: Calculate the loop gain based on the input impedance and the output impedance, and use the Nyquist stability criterion to analyze whether the system is small signal stable; Step 7, record the data matrix; Step 8: Determine whether all variables of interest have been analyzed. If not, return to step 3 to analyze the next variable. If yes, derive a data matrix and obtain the passband frequency parameters of the second-order bandpass filter based on the data matrix.

7. The variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive according to claim 1, characterized in that: The forward channel second gain module and the current feedforward gain module have a control structure and variable parameter properties. The control modes of the forward channel second gain module and the current feedforward gain module include one of a proportional mode and a proportional integral mode, and the control mode is determined by the switching process requirements.

8. The variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive according to claim 2, characterized in that: The frequency and voltage amplitude reference value generation module has three modes: droop, constant voltage and constant frequency, and variable voltage and variable frequency.

9. The variable structure control device for auxiliary power supply inverter of variable voltage and variable frequency locomotive according to claim 2, characterized in that: The controller normalized gain module is a proportional gain, and the preferred gain value is the inverse of the rated voltage of the system DC bus.

10. A variable structure control system for auxiliary power supply inverter of variable voltage and variable frequency locomotive, characterized in that: The control system includes: a control device as described in any one of claims 1 to 9, a semiconductor power module, a filter and a load bus port, the semiconductor power module is connected to the filter, the control device is connected to the semiconductor power module and the filter respectively, and the load bus port is connected to the filter.

11. A variable structure control method for auxiliary power supply inverter of variable voltage and variable frequency locomotive, characterized in that: The method comprises the following steps: The frequency and voltage amplitude reference value generation module generates a power supply bus frequency reference value and a voltage reference value; The coordinate transformation module processes the voltage and current signals obtained by feedback based on the power supply bus frequency reference value; Subtracting the direct-axis and quadrature-axis voltages obtained after processing from the voltage reference value to obtain difference information; The voltage loop controller implements feedback control-based regulation on the bus voltage based on the difference information to obtain a regulation signal; The second gain module of the forward channel performs secondary regulation on the regulation signal to control the current; The source-load instability detection module determines whether the railway locomotive auxiliary power supply system has a source-load instability phenomenon based on the difference information; The current feedforward gain module adjusts the overall control structure of the system through gain parameters and setting modes, thereby achieving seamless switching between the two control modes; The controller normalization gain module performs secondary calibration on the control output; A pulse width modulation signal is generated based on the output of the controller normalized gain module to control the semiconductor power module.

12. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to claim 11 are implemented.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 11 are implemented.

14. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method of claim 11 are implemented.

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