A multi-feed brushless generator system and its control method

Abstract

This application belongs to the field of brushless generator technology, specifically disclosing a multi-feed brushless generator system and its control method. In this system, the control module generates a PWM pulse modulation signal, and the low-voltage generator-side converter provides excitation current to the control winding according to the PWM pulse modulation signal; the multi-feed brushless generator outputs medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current; the medium-voltage uncontrolled rectifier converts the medium-voltage AC power output from the medium-voltage power winding side into medium-voltage DC power; the low-voltage controlled rectifier converts the low-voltage AC power output from the low-voltage power winding side into low-voltage DC power according to the PWM pulse modulation signal; this system can simultaneously supply power to DC systems of both medium and low voltage levels, and power quality regulation can be achieved through the coordinated control of the low-voltage controlled rectifier and the low-voltage generator-side converter.

Description

Technical Field

[0001] This application belongs to the field of brushless generator technology, and more specifically, relates to a multi-feed brushless generator system and its control method. Background Technology

[0002] Currently, the medium-voltage DC bus voltage level used in integrated power systems for large-tonnage, high-speed ships has reached 4-10kV, and will reach 30kV in the future, with capacity gradually increasing from 10MW to 200MW. Electronic equipment and routine daily loads typically use low-voltage DC bus power supplies with a voltage level of 700-1000V. To achieve a hybrid medium- and low-voltage DC power supply, the existing method is to use a topology combining a medium-voltage DC power generation system with a megawatt-level high-capacity DC-DC converter in series.

[0003] The current medium- and low-voltage DC hybrid power supply system has the following main defects: (1) In terms of system topology, the generator system only outputs medium-voltage DC power, and it needs to rely on a large-capacity DC-DC converter connected in series to realize the power conversion from medium-voltage to low-voltage DC. The power density of the whole system is low; and the power electronic devices of the large-capacity DC-DC converter are used in large quantities, which seriously reduces the reliability of the system; (2) In terms of control strategy, the control of the generator system and the DC-DC converter is essentially cascade control. Their control inertia is different, which makes it difficult to match the dynamic characteristics of the generator and the converter, and it is easy to cause mutual interference and system oscillation, resulting in insufficient system stability. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the existing technology, this application provides a multi-feed brushless generator system, which aims to solve the technical problems of insufficient reliability and stability of the current medium and low voltage DC hybrid power supply system.

[0005] To achieve the above objectives, in a first aspect, this application provides a multi-feed brushless generator system, including a topology module and a control module. The control module is used to generate a first PWM pulse modulation signal and a second PWM pulse modulation signal based on feedback values ​​of low-voltage DC and medium-voltage DC. The topology module includes:

[0006] The low-voltage side converter is used to provide excitation current to the control winding side of the multi-feed brushless generator according to the first PWM pulse modulation signal;

[0007] Multi-feed brushless generators are used to output medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current.

[0008] Medium-voltage uncontrolled rectifier is used to convert the medium-voltage AC power output from the medium-voltage power winding side of a multi-feed brushless generator into medium-voltage DC power.

[0009] A low-voltage controllable rectifier is used to convert the low-voltage AC power output from the low-voltage power winding side of a multi-feed brushless generator into low-voltage DC power according to a second PWM pulse modulation signal.

[0010] Preferably, the multi-feed brushless generator includes a medium-voltage power winding, a low-voltage power winding, and a control winding with different numbers of pole pairs; wherein, the medium-voltage power winding and the control winding are coupled through the rotor; the low-voltage power winding and the control winding are coupled through the rotor; and the medium-voltage power winding and the low-voltage power winding are coupled through the rotor.

[0011] Preferably, the topology module further includes a low-voltage DC bus capacitor, which is connected in parallel with the DC side of the low-voltage controllable rectifier and the DC side of the low-voltage generator-side converter. The low-voltage DC bus capacitor is used to filter out harmonic components in the low-voltage DC power and store energy.

[0012] Preferably, the control module includes:

[0013] The medium-voltage DC output voltage control module is used to calculate the difference between the reference value and the feedback value of the medium-voltage DC power, and then, through PI control, obtain the control winding current. Axis component reference values;

[0014] The control winding frequency calculation module is used to obtain the frequency of the control winding based on the rotational speed of the multi-feed brushless generator, the rated frequency of the medium-voltage power winding, and the rated frequency of the low-voltage power winding.

[0015] A control winding frequency integrator is used to integrate the frequency of the control winding to obtain a reference angle.

[0016] A control winding current conversion module is used to convert the current on the control winding side according to the reference angle. Phase current is converted into control winding current. Shaft component feedback value and Shaft component feedback value;

[0017] The winding current control module is used to control the winding current. Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; will control the winding current. Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; the control winding current The reference value for the axis component is zero;

[0018] A control winding voltage conversion module is used to convert the control winding voltage according to the reference angle. Shaft component reference values ​​and Shaft component reference value transformed into control winding voltage Shaft component reference values ​​and Axis component reference values;

[0019] A control winding SVPWM generator is used to control the winding voltage. Shaft component reference values ​​and The axis component reference value generates the first PWM pulse modulation signal.

[0020] Preferably, the rotational speed of the multi-feed brushless generator satisfies:

[0021] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence:

[0022]

[0023] When the equivalent low-voltage power rotor winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in phase sequence with the control rotor winding:

[0024]

[0025] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in phase sequence:

[0026]

[0027] When the equivalent low-voltage rotor power winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in reverse phase sequence with the control rotor winding:

[0028]

[0029] in, The rotational speed of the multi-feed brushless generator, To control the winding frequency, To control the number of pole pairs in the winding, This is the frequency of the low-voltage power winding. This refers to the frequency of the medium-voltage power winding. This refers to the number of pole pairs in the low-voltage power winding. This represents the number of pole pairs in the medium-voltage power winding.

[0030] Preferably, the control module further includes:

[0031] The low-voltage DC output voltage control module is used to obtain the low-voltage power winding current by subtracting the reference value and feedback value of the low-voltage DC power supply and then controlling it via PI control. Axis component reference values;

[0032] A low-voltage power winding voltage phase-locked loop is used to obtain the voltage phase based on the three-phase voltage on the low-voltage power winding side;

[0033] A low-voltage power winding current conversion module is used to convert the current of the low-voltage power winding side according to the voltage phase. Phase current is converted into low-voltage power winding current. Shaft component feedback value and Shaft component feedback value;

[0034] The low-voltage power winding current control module is used to control the low-voltage power winding current. After subtracting the shaft component reference value from the feedback value, the low-voltage power winding voltage is obtained through PI control. Shaft component reference value; The low-voltage power winding current... The difference between the shaft component reference value and the feedback value is used to obtain the low-voltage power winding voltage via PI control. Shaft component reference value; low-voltage power winding current The reference value for the axis component is zero;

[0035] A low-voltage power winding voltage conversion module is used to convert the low-voltage power winding voltage according to the voltage phase. Shaft component reference values ​​and The shaft component reference value is transformed into the low-voltage power winding voltage. Shaft component reference values ​​and Axis component reference values;

[0036] Low-voltage controlled rectifier SVPWM generator, used to generate a low-voltage power winding voltage. Shaft component reference values ​​and The axis component reference value is used to generate the second PWM pulse modulation signal.

[0037] Secondly, this application provides a control method for a multi-feed brushless generator system, the method comprising the following steps:

[0038] According to the first PWM pulse modulation signal, excitation current is provided to the control winding side of the multi-feed brushless generator;

[0039] The multi-feed brushless generator outputs medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current.

[0040] Convert the medium-voltage AC power output from the medium-voltage power winding side of the multi-feed brushless generator into medium-voltage DC power;

[0041] The low-voltage AC power output from the low-voltage power winding side of the multi-feed brushless generator is converted into low-voltage DC power according to the second PWM pulse modulation signal.

[0042] The first PWM pulse modulation signal and the second PWM pulse modulation signal are generated based on the low-voltage DC and medium-voltage DC.

[0043] Preferably, the first PWM pulse modulation signal is obtained through the following method:

[0044] The difference between the reference value and the feedback value of the medium-voltage DC current is used to obtain the control winding current through PI control. Axis component reference values;

[0045] The frequency of the control winding is obtained based on the rotational speed of the multi-feed brushless generator, the rated frequency of the medium-voltage power winding, and the rated frequency of the low-voltage power winding.

[0046] The reference angle is obtained by integrating the frequency of the control winding;

[0047] Based on the reference angle, the control winding side will be... Phase current is converted into control winding current. Shaft component feedback value and Shaft component feedback value;

[0048] Control the winding current Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Axis component reference values;

[0049] Control the winding current Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; the control winding current The reference value for the axis component is zero;

[0050] Based on the aforementioned reference angle, the control winding voltage will be... Shaft component reference values ​​and Shaft component reference value transformed into control winding voltage Shaft component reference values ​​and Axis component reference values;

[0051] According to the control winding voltage Shaft component reference values ​​and The axis component reference value generates the first PWM pulse modulation signal.

[0052] Preferably, the rotational speed of the multi-feed brushless generator satisfies:

[0053] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence:

[0054]

[0055] When the equivalent low-voltage power rotor winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in phase sequence with the control rotor winding:

[0056]

[0057] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in phase sequence:

[0058]

[0059] When the equivalent low-voltage rotor power winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in reverse phase sequence with the control rotor winding:

[0060]

[0061] in, The rotational speed of the multi-feed brushless generator, To control the winding frequency, To control the number of pole pairs in the winding, This is the frequency of the low-voltage power winding. This refers to the frequency of the medium-voltage power winding. This refers to the number of pole pairs in the low-voltage power winding. This represents the number of pole pairs in the medium-voltage power winding.

[0062] Preferably, the second PWM pulse modulation signal is obtained through the following method:

[0063] The difference between the reference value and the feedback value of the low-voltage DC current is calculated, and then the low-voltage power winding current is obtained through PI control. Axis component reference values;

[0064] The voltage phase is obtained from the three-phase voltage on the low-voltage power winding side;

[0065] Based on the voltage phase, the low-voltage power winding side Phase current is converted into low-voltage power winding current. Shaft component feedback value and Shaft component feedback value;

[0066] The low-voltage power winding current After subtracting the shaft component reference value from the feedback value, the low-voltage power winding voltage is obtained through PI control. Shaft component reference value; The low-voltage power winding current... The difference between the shaft component reference value and the feedback value is used to obtain the low-voltage power winding voltage via PI control. Shaft component reference value; low-voltage power winding current The reference value for the axis component is zero;

[0067] Based on the voltage phase, the low-voltage power winding voltage... Shaft component reference values ​​and The shaft component reference value is transformed into the low-voltage power winding voltage. Shaft component reference values ​​and Axis component reference values;

[0068] Low-voltage controlled rectifier SVPWM generator, used to generate a low-voltage power winding voltage. Shaft component reference values ​​and The axis component reference value is used to generate the second PWM pulse modulation signal.

[0069] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art:

[0070] (1) The low-voltage DC hybrid power supply system in this application can realize the hybrid output of medium and low voltage power through a single multi-feed brushless generator. The controllable converters used in the system of this application are all low-voltage converters, which greatly improves the power density and reliability of the system.

[0071] (2) The low-voltage DC hybrid power supply system in this application abandons the traditional cascade control mode. It can synchronously regulate the medium-voltage DC bus and the low-voltage DC bus through the low-voltage generator side converter, and can realize the control without medium-voltage DC bus capacitor.

[0072] (3) In this application, the low-voltage DC hybrid power supply system uses a low-voltage controllable rectifier to control the low-voltage power winding and a low-voltage generator-side converter to control the control winding. Through the coordinated control of the low-voltage controllable rectifier and the low-voltage generator-side converter, power quality regulation can be achieved.

[0073] (4) This application proposes a novel topology for a multi-feed brushless generator, in which the multi-feed brushless generator includes three sets of windings with different numbers of pole pairs: a medium-voltage power winding, a low-voltage power winding, and a low-voltage control winding, and all of them are coupled to each other through a rotor. Attached Figure Description

[0074] Figure 1This is a schematic diagram of the signal flow of a multi-feed brushless generator system provided in an embodiment of this application.

[0075] Figure 2 This is a schematic diagram of the topology module structure provided in the embodiments of this application.

[0076] Figure 3 This is a schematic diagram of the control module structure provided in an embodiment of this application.

[0077] Figure 4 This is a schematic diagram of a multi-feed brushless generator system provided in an embodiment of this application.

[0078] Figure 5 This is a block diagram illustrating the medium-voltage DC output voltage control principle provided in the embodiments of this application.

[0079] Figure 6 This is a block diagram illustrating the control winding current control principle provided in an embodiment of this application.

[0080] Figure 7 This is a block diagram illustrating the low-voltage DC output voltage control principle provided in an embodiment of this application.

[0081] Figure 8 This is a block diagram illustrating the low-voltage power winding current control principle provided in the embodiments of this application. Detailed Implementation

[0082] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0083] The terms "first" and "second," etc., used in the description and claims herein are used to distinguish different objects, not to describe a specific order of objects. For example, "first PWM pulse modulation signal" and "second PWM pulse modulation signal," etc., are used to distinguish different PWM pulse modulation signals, not to describe a specific order of PWM pulse modulation signals.

[0084] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0085] This application provides an embodiment of a brushless multi-feed generator system, such as... Figure 1As shown, the system includes a topology module and a control module. The control module receives the three-phase current of the control winding, the three-phase current of the low-voltage power winding, the three-phase voltage of the low-voltage power winding, the motor speed, the reference value of the medium-voltage DC bus voltage, the feedback value of the medium-voltage DC bus voltage, the reference value of the low-voltage DC bus voltage, and the feedback value of the low-voltage DC bus voltage from the topology module. After PI control and coordinate transformation, it uses an SVPWM generator to output two PWM pulse modulation signals. The topology module uses the two PWM pulse modulation signals provided by the control module to control the brushless multi-feed generator, thereby enabling simultaneous power supply to the system at both medium and low voltage levels.

[0086] like Figure 2 As shown, the topology module includes: a multi-feed brushless generator, a low-voltage DC bus capacitor, a medium-voltage uncontrolled rectifier, a low-voltage controlled rectifier, and a low-voltage generator-side converter.

[0087] A multi-feed brushless generator consists of three sets of windings with different numbers of pole pairs: a medium-voltage power winding, a low-voltage power winding, and a low-voltage control winding. The medium-voltage power winding is coupled to the control winding through the rotor; the low-voltage power winding is coupled to the control winding through the rotor; and the medium-voltage power winding is coupled to the low-voltage power winding through the rotor.

[0088] The AC side of the medium-voltage uncontrolled rectifier is connected to the medium-voltage power winding of the multi-feed brushless generator; the AC side of the low-voltage controlled rectifier is connected to the low-voltage power winding of the multi-feed brushless generator; the AC side of the low-voltage generator-side converter is connected to the low-voltage control winding of the multi-feed brushless generator; the DC side of the low-voltage controlled rectifier and the DC side of the low-voltage generator-side converter are connected in parallel with the low-voltage DC bus capacitor.

[0089] The medium-voltage uncontrolled rectifier is used to convert the AC voltage output from the medium-voltage power winding side into DC voltage; the low-voltage generator-side converter is used to provide excitation current to the low-voltage control winding according to the PWM pulse modulation signal of the low-voltage generator-side converter; the low-voltage controlled rectifier is used to adjust the low-voltage power winding current and control the low-voltage DC voltage according to the PWM pulse modulation signal of the low-voltage controlled rectifier; the low-voltage DC bus capacitor is used to filter out harmonic components in the low-voltage DC voltage and store energy.

[0090] like Figure 3 As shown,

[0091] The control module consists of two parts. The first part includes:

[0092] Medium-voltage DC output voltage control module, control winding current control module, control winding voltage conversion module, control winding current conversion module, control winding frequency integrator, low-voltage generator-side converter SVPWM generator, and control winding frequency calculation module.

[0093] The connection relationship is as follows:

[0094] The medium-voltage DC output voltage control module, the control winding current control module, the control winding voltage conversion module, and the low-voltage generator-side converter SVPWM generator are connected in sequence.

[0095] The first input terminal of the control winding current conversion module is connected to the control winding, its second input terminal is connected to the first output terminal of the control winding frequency integrator, and its output terminal is connected to the input terminal of the control winding current control module.

[0096] The second output terminal of the control winding frequency integrator is connected to the input terminal of the control winding voltage conversion module.

[0097] The functions of each part are as follows:

[0098] The medium-voltage DC output voltage control module controls the voltage based on the reference value of the medium-voltage DC bus voltage. Feedback value of medium-voltage DC bus voltage after low-pass filter Through PI control, the medium-voltage DC bus voltage is adjusted to obtain the control winding current. Axis component reference value .

[0099] The winding current control module controls the winding current based on the winding current. Axis component reference value and control winding current Shaft component feedback value The PI control controls the winding current. The shaft component is adjusted to obtain the control winding voltage. Axis component reference value .

[0100] And according to the control winding current Axis component reference value and control winding current Shaft component feedback value The PI control controls the winding current. The shaft component is adjusted to obtain the control winding voltage. Axis component reference value .

[0101] The control winding voltage conversion module is used to convert the rotating winding voltage. Control winding voltage in coordinate system Axis component reference value and control winding voltage Axis component reference value Transformed into two-phase stationary Control winding voltage in coordinate system Axis component reference value and Axis component reference value .

[0102] The control winding frequency integrator is used to integrate the control winding frequency to obtain the reference angle for the control winding voltage conversion module and the control winding current conversion module. .

[0103] The control winding current conversion module is used to collect data from the control winding side of the brushless multi-feed generator. Phase current and Phase current Transform into Controlling winding current in coordinate system Shaft component feedback value and current Shaft component feedback value .

[0104] The SVPWM generator of the low-voltage side converter uses the ideal flux linkage circle of the stator of the three-phase symmetrical motor as a reference standard when powered by a three-phase symmetrical sinusoidal voltage. It makes appropriate switching according to different switching modes of the three-phase inverter to generate the PWM pulse signal of the low-voltage side converter.

[0105] The control winding frequency calculation module and the low-voltage power winding frequency calculation module calculate the frequency based on the motor speed. With the rated frequency of medium voltage power winding Under different phase sequence connection methods, obtain the control winding frequency. The calculation method is as follows:

[0106] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, the relationship between the rotor speed, the frequency of the medium-voltage power winding, the frequency of the control winding, and the frequency of the low-voltage power winding is as follows: ;

[0107] When the equivalent low-voltage power rotor winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in phase sequence with the control rotor winding, the relationship between the rotor speed, the frequency of the medium-voltage power winding, the frequency of the control winding, and the frequency of the low-voltage power winding is as follows: ;

[0108] When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in phase sequence, the relationship between the rotor speed, the frequency of the medium-voltage power winding, the frequency of the control winding, and the frequency of the low-voltage power winding is as follows: ;

[0109] When the equivalent low-voltage power rotor winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in opposite phase sequence with the control rotor winding, the relationship between the rotor speed, the frequency of the medium-voltage power winding, the frequency of the control winding, and the frequency of the low-voltage power winding is as follows: ;

[0110] in, This is the frequency of the low-voltage power winding; This refers to the frequency of the medium-voltage power winding. To control the winding frequency; Rotor speed; This refers to the number of pole pairs in the low-voltage power winding. This refers to the number of pole pairs in the medium-voltage power winding. To control the number of pole pairs in the winding.

[0111] Part Two contains:

[0112] Low-voltage DC output voltage control module, low-voltage power winding current control module, low-voltage power winding voltage conversion module, low-voltage power winding current conversion module, low-voltage generator-side converter SVPWM generator, and control winding voltage phase-locked loop.

[0113] The connection relationship is as follows:

[0114] The low-voltage DC output voltage control module, the low-voltage power winding current control module, the low-voltage power winding voltage conversion module, and the low-voltage controllable rectifier SVPWM generator are connected in sequence.

[0115] The first input terminal of the low-voltage power winding current conversion module is connected to the low-voltage power winding, its second input terminal is connected to the first output terminal of the low-voltage power winding voltage phase-locked loop, and its output terminal is connected to the input terminal of the low-voltage power winding current control module.

[0116] The second output terminal of the low-voltage power winding voltage phase-locked loop is connected to the input terminal of the low-voltage power winding voltage conversion module.

[0117] The functions of each part are as follows:

[0118] The low-voltage DC output voltage control module uses the reference value of the low-voltage DC bus voltage. Feedback value of low-voltage DC bus voltage after passing through low-pass filter Through PI control, the low-voltage DC bus voltage is adjusted to obtain the low-voltage power winding current. Axis component reference value .

[0119] The low-voltage power winding current control module controls the low-voltage power winding current based on the low-voltage power winding current. Axis component reference value and low-voltage power winding current Shaft component feedback value The low-voltage power winding current is controlled by PI control. The shaft component is adjusted to obtain the low-voltage power winding voltage. Axis component reference value .

[0120] And based on the low-voltage power winding current Axis component reference value and low-voltage power winding current Shaft component feedback value The low-voltage power winding current is controlled by PI control. The shaft component is adjusted to obtain the low-voltage power winding voltage. Axis component reference value .

[0121] The low-voltage power winding voltage conversion module is used to convert the rotating... Low-voltage power winding voltage in coordinate system Axis component reference value and low-voltage power winding voltage Axis component reference value Transformed into two-phase stationary Low-voltage power winding voltage in coordinate system Axis component reference value and Axis component reference value .

[0122] The low-voltage power winding voltage phase-locked loop is used to calculate the low-voltage power winding voltage phase, which serves as the reference angle for both the low-voltage power winding voltage conversion module and the low-voltage power winding current conversion module.

[0123] The low-voltage power winding current conversion module is used to collect current from the low-voltage power winding side of the brushless multi-feed generator. Phase current and Phase current Transform into Low-voltage power winding current in coordinate system Shaft component feedback value and current Shaft component feedback value .

[0124] The low-voltage controllable rectifier SVPWM generator uses the ideal flux linkage circle of the stator of a three-phase symmetrical motor as a reference standard when powered by a three-phase symmetrical sinusoidal voltage. It makes appropriate switching according to different switching modes of the three-phase inverter to generate the PWM pulse signal of the low-voltage controllable rectifier.

[0125] Example 1

[0126] Example 1 is a brushless multi-feed generator system, such as Figure 4 As shown, it includes a topology module and a control module;

[0127] The topology module includes: multi-feed brushless generator, low-voltage DC bus capacitor, medium-voltage uncontrolled rectifier, low-voltage controlled rectifier, and low-voltage generator-side converter;

[0128] Multi-feed brushless generators consist of three sets of windings with different numbers of pole pairs: a medium-voltage power winding, a low-voltage power winding, and a low-voltage control winding.

[0129] The medium-voltage power winding is coupled to the control winding via the rotor; the low-voltage power winding is coupled to the control winding via the rotor; the medium-voltage power winding and the low-voltage power winding are coupled via the rotor.

[0130] The AC side of the medium-voltage uncontrolled rectifier is connected to the medium-voltage power winding of the multi-feed brushless generator; the AC side of the low-voltage controlled rectifier is connected to the low-voltage power winding of the multi-feed brushless generator; the AC side of the low-voltage generator-side converter is connected to the low-voltage control winding of the multi-feed brushless generator; the DC side of the low-voltage controlled rectifier and the DC side of the low-voltage generator-side converter are connected in parallel with the low-voltage DC bus capacitor;

[0131] Medium-voltage uncontrolled rectifiers are used to convert the AC voltage output from the medium-voltage power winding side into DC voltage;

[0132] The low-voltage generator-side converter is used to provide excitation current to the low-voltage control winding according to the PWM pulse modulation signal of the low-voltage generator-side converter;

[0133] The low-voltage controllable rectifier is used to adjust the low-voltage power winding current and control the low-voltage DC voltage according to the PWM pulse modulation signal of the low-voltage controllable rectifier.

[0134] Low-voltage DC bus capacitors are used to filter out harmonic components in low-voltage DC voltage and store energy.

[0135] In practical applications, the low-voltage DC power, after being filtered by the low-voltage DC bus capacitor, is connected to the low-voltage DC bus to supply power to the low-voltage DC load or to operate in parallel with the low-voltage DC grid; the medium-voltage DC power is connected to the medium-voltage DC bus to supply power to the medium-voltage DC load or to operate in parallel with the medium-voltage DC grid.

[0136] Therefore, the topology module can achieve mixed output of medium and low voltage power through a single generator, and the controllable converters used in the control system are all low voltage converters, which greatly improves the system power density and reliability.

[0137] The control module includes: a medium-voltage DC output voltage control module, a control winding current control module, a control winding voltage conversion module, a control winding current conversion module, a control winding frequency integrator, a low-voltage generator-side converter SVPWM generator, a control winding frequency calculation module, a low-voltage DC output voltage control module, a low-voltage power winding current control module, a low-voltage power winding voltage conversion module, a low-voltage power winding current conversion module, a low-voltage generator-side converter SVPWM generator, and a control winding voltage phase-locked loop;

[0138] The medium-voltage DC output voltage control module controls the voltage based on the reference value of the medium-voltage DC bus voltage. Feedback value of medium-voltage DC bus voltage after low-pass filter Through PI control, the low-voltage DC bus voltage is adjusted to obtain the control winding current. Axis component reference value .

[0139] Specifically, such as Figure 5 As shown, the medium-voltage DC output voltage control module includes a low-pass filter, a first adder, and a first PI regulator;

[0140] Feedback value of low-pass filter to medium-voltage DC bus voltage Filtering is performed to obtain a noise-free medium-voltage DC bus voltage feedback value. ;

[0141] First adder calculation Reference value of medium voltage DC bus voltage The difference is calculated and input to the first PI controller.

[0142] The first PI regulator performs PI control on this difference, outputting a control winding current. Axis component reference value .

[0143] Among them, controlling the winding current Axis component reference value It is 0.

[0144] The specific calculation formula for the low-pass filter is as follows:

[0145]

[0146] in, This is the current noiseless medium-voltage DC bus voltage feedback value of the multi-feed brushless generator; For the first The feedback value of the current noisy medium-voltage DC bus voltage of the multi-feed brushless generator obtained from the calculation; This is the cutoff frequency of the first low-pass filter; The sampling period is determined by the hardware used by the user. For the first The feedback value of the current noisy medium-voltage DC bus voltage of the multi-feed brushless generator obtained from the calculation; The input is fed into the first PI regulator.

[0147] The winding current control module controls the winding current based on the winding current. Axis component reference value and control winding current Shaft component feedback value The PI control controls the winding current. The shaft component is adjusted to obtain the control winding voltage. Axis component reference value On the other hand, based on the control winding current... Axis component reference value and control winding current Shaft component feedback value The PI control controls the winding current. The shaft component is adjusted to obtain the control winding voltage. Axis component reference value .

[0148] Specifically, such as Figure 6 As shown, the control winding current control module includes a second adder, a third adder, a second PI regulator, and a third PI regulator;

[0149] The second adder is used to control the winding current. Axis component reference value With control of winding current Shaft component feedback value make a mistake;

[0150] The second PI regulator is used to... Perform PI control to obtain the control winding voltage. Axis component reference value ;

[0151] The third adder is used to control the winding current. Axis component reference value With control of winding current Shaft component feedback value Difference; where the control winding current is... Axis component reference value Equal to 0;

[0152] The third PI controller is used for... Perform PI control to obtain the control winding voltage. Axis component reference value .

[0153] The control winding voltage conversion module is used to convert the rotating winding voltage. Control winding voltage in coordinate system Axis component reference value and control winding voltage Axis component reference value Transformed into two-phase stationary Control winding voltage in coordinate system Axis component reference value and Axis component reference value .

[0154] The specific method is as follows:

[0155] An integrator is used to control the winding frequency. The reference angles for the control winding voltage transformation module and the control winding current transformation module are obtained by integration. ;Specifically:

[0156]

[0157] in, The current given value for controlling the phase of the winding voltage; T The sampling period is determined by the hardware used by the user; the number of operations... j =1、…、 n ; Indicates the first j The current given value of the control winding voltage frequency obtained from this calculation; its calculation result The voltage is fed into the control winding voltage conversion module.

[0158] use Control winding voltage Axis component reference value and control winding voltage Axis component reference value From rotation Coordinate system transformation to two-phase stationary A coordinate system is used to obtain the control winding voltage. Axis component reference value and Axis component reference value The transformation expression is:

[0159]

[0160] According to the control winding voltage Axis component reference value and Axis component reference value The SVPWM algorithm is used to generate a modulation signal, so that the low-voltage side converter outputs the corresponding excitation current to the control winding.

[0161] The control winding current conversion module is used to collect data from the control winding side of the brushless multi-feed generator. Phase current and Phase current Transform into Controlling winding current in coordinate system Shaft component feedback value and current Shaft component feedback value .

[0162] The specific method is as follows:

[0163] Based on the collected data of the multi-feed brushless generator control winding Phase current and Phase current Calculate the control winding Phase current The calculation method is as follows:

[0164]

[0165] Using the control winding current reference value The three-phase current of the control winding is transformed into Controlling winding current in coordinate system Shaft component feedback value and current Shaft component feedback value The specific transformation method is as follows:

[0166]

[0167] The control winding frequency calculation module calculates the frequency based on the motor speed. With the rated frequency of medium voltage power winding Under different phase sequence connection methods, obtain the control winding frequency. The calculation method is as follows:

[0168] When the equivalent medium-voltage power rotor winding and the control rotor winding are connected in reverse phase sequence, the relationship between the rotor speed, the rated frequency of the power winding, and the frequency of the control winding is as follows: ;

[0169] When the equivalent medium-voltage power rotor winding and the control rotor winding are connected in phase sequence, the relationship between the rotor speed, the rated frequency of the power winding, and the frequency of the control winding is as follows: ;

[0170] in, This refers to the number of pole pairs in the medium-voltage power winding. To control the number of pole pairs in the winding.

[0171] The low-voltage DC output voltage control module uses the reference value of the low-voltage DC bus voltage. Feedback value of low-voltage DC bus voltage after passing through low-pass filter Through PI control, the low-voltage DC bus voltage is adjusted to obtain the low-voltage power winding current. Axis component reference value ;

[0172] Specifically, such as Figure 7 As shown, the low-voltage DC output voltage control module includes a low-pass filter, a fourth adder, and a fourth PI regulator;

[0173] Feedback value of low-pass filter to low-voltage DC bus voltage Filtering is performed to obtain a noise-free low-voltage DC bus voltage feedback value. ;

[0174] Fourth adder calculation Reference value of low-voltage DC bus voltage The difference is then input to the fourth PI controller;

[0175] The fourth PI regulator performs PI control on this difference, outputting the low-voltage power winding current. Axis component reference value .

[0176] Among them, the low-voltage power winding current Axis component reference value =0;

[0177] The specific calculation formula for the low-pass filter is as follows:

[0178]

[0179] in, This is the current noiseless low-voltage DC bus voltage feedback value of the multi-feed brushless generator; For the first The feedback value of the current noisy low-voltage DC bus voltage of the multi-feed brushless generator obtained from the calculation; This is the cutoff frequency of the first low-pass filter; The sampling period is determined by the hardware used by the user. For the first The feedback value of the current noisy low-voltage DC bus voltage of the multi-feed brushless generator is obtained from the calculation; The input is sent to the fourth PI regulator.

[0180] The low-voltage power winding current control module controls the low-voltage power winding current based on the low-voltage power winding current. Axis component reference value and low-voltage power winding current Shaft component feedback value The low-voltage power winding current is controlled by PI control. The shaft component is adjusted to obtain the low-voltage power winding voltage. Axis component reference value On the other hand, based on the low-voltage power winding current... Axis component reference value and low-voltage power winding current Shaft component feedback value The low-voltage power winding current is controlled by PI control. The shaft component is adjusted to obtain the low-voltage power winding voltage. Axis component reference value .

[0181] Specifically, such as Figure 8 As shown, the low-voltage power winding current control module includes a fifth adder, a sixth adder, a fifth PI regulator, and a sixth PI regulator.

[0182] The fifth adder is used to convert the low-voltage power winding current. Axis component reference value With low-voltage power winding current Shaft component feedback value make a mistake;

[0183] The fifth PI regulator is used for... Perform PI control to obtain the low-voltage power winding voltage. Axis component reference value ;

[0184] The sixth adder is used to convert the low-voltage power winding current... Axis component reference value With low-voltage power winding current Shaft component feedback value Difference; where the low-voltage power winding current is... Axis component reference value Equal to 0;

[0185] The sixth PI controller is used for... Perform PI control to obtain the low-voltage power winding voltage. Axis component reference value .

[0186] The low-voltage power winding voltage conversion module is used to convert the rotating... Low-voltage power winding voltage in coordinate system Axis component reference value and low-voltage power winding voltage Axis component reference value Transformed into two-phase stationary Low-voltage power winding voltage in coordinate system Axis component reference value and Axis component reference value .

[0187] use Low-voltage power winding voltage Axis component reference value and low-voltage power winding voltage Axis component reference value From rotation Coordinate system transformation to two-phase stationary Using a coordinate system, the voltage of the low-voltage power winding is obtained. Axis component reference value and Axis component reference value The transformation expression is:

[0188]

[0189] Based on the voltage of the low-voltage power group Axis component reference value and Axis component reference value The SVPWM algorithm is used to generate a modulation signal, which enables the low-voltage controllable rectifier to output the corresponding excitation current to the low-voltage power winding.

[0190] The low-voltage power winding current conversion module is used to collect current from the low-voltage power winding side of the brushless multi-feed generator. Phase current and Phase current Transform into Low-voltage power winding current in coordinate system Shaft component feedback value and current Shaft component feedback value .

[0191] The specific method is as follows:

[0192] Based on the collected data of the low-voltage power winding of the multi-feed brushless generator Phase current and Phase current Calculate the low-voltage power winding Phase current The calculation method is as follows:

[0193]

[0194] Using low-voltage power winding current reference value The three-phase current of the low-voltage power winding is transformed into... Low-voltage power winding current in coordinate system Shaft component feedback value and current Shaft component feedback value The specific transformation method is as follows:

[0195]

[0196] Example 2

[0197] Example 2 is a control method for a multi-feed brushless generator system, the control method comprising:

[0198] Based on the first PWM pulse modulation signal, excitation current is provided to the control winding of the multi-feed brushless generator;

[0199] The multi-feed brushless generator outputs medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current;

[0200] Convert the medium-voltage AC power output from the medium-voltage power winding side into medium-voltage DC power;

[0201] The low-voltage AC power output from the low-voltage power winding side is converted into low-voltage DC power according to the second PWM pulse modulation signal.

[0202] The first PWM pulse modulation signal and the second PWM pulse modulation signal are generated based on the low-voltage DC and medium-voltage DC.

[0203] It should be understood that the above method embodiments are used to control the system in the above embodiment 1. The implementation principle and technical effect of the corresponding steps in the method are similar to those described in the above embodiment 1. The specific steps of the method can be referred to the corresponding process in the above embodiment 1, and will not be repeated here.

[0204] It is understood that the various numerical designations used in the embodiments of this application are merely for the convenience of description and are not intended to limit the scope of the embodiments of this application.

[0205] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A multi-feed brushless generator system, characterized in that, The system includes a topology module and a control module. The control module generates a first PWM pulse modulation signal and a second PWM pulse modulation signal based on feedback values ​​from the low-voltage DC and medium-voltage DC currents. The topology module includes: The low-voltage side converter is used to provide excitation current to the control winding side of the multi-feed brushless generator according to the first PWM pulse modulation signal; Multi-feed brushless generators are used to output medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current. Medium-voltage uncontrolled rectifier is used to convert the medium-voltage AC power output from the medium-voltage power winding side of a multi-feed brushless generator into medium-voltage DC power. A low-voltage controllable rectifier is used to convert the low-voltage AC power output from the low-voltage power winding side of a multi-feed brushless generator into low-voltage DC power according to a second PWM pulse modulation signal. The rotational speed of the multi-feed brushless generator satisfies: When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence: When the equivalent low-voltage power rotor winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in phase sequence with the control rotor winding: When the equivalent low-voltage power rotor winding is connected to the control rotor winding in reverse phase sequence, and the equivalent medium-voltage power rotor winding is connected to the control rotor winding in phase sequence: When the equivalent low-voltage rotor power winding is connected in phase sequence with the control rotor winding, and the equivalent medium-voltage power rotor winding is connected in reverse phase sequence with the control rotor winding: in, The rotational speed of the multi-feed brushless generator, To control the winding frequency, To control the number of pole pairs in the winding, This is the frequency of the low-voltage power winding. This refers to the frequency of the medium-voltage power winding. This refers to the number of pole pairs in the low-voltage power winding. This represents the number of pole pairs in the medium-voltage power winding.

2. The multi-feed brushless generator system according to claim 1, characterized in that, The multi-feed brushless generator includes a medium-voltage power winding, a low-voltage power winding, and a control winding with different numbers of pole pairs; wherein, the medium-voltage power winding and the control winding are coupled through the rotor; the low-voltage power winding and the control winding are coupled through the rotor; and the medium-voltage power winding and the low-voltage power winding are coupled through the rotor.

3. The multi-feed brushless generator system according to claim 1, characterized in that, The topology module also includes a low-voltage DC bus capacitor, which is connected in parallel with the DC side of the low-voltage controllable rectifier and the DC side of the low-voltage generator converter. The low-voltage DC bus capacitor is used to filter out harmonic components in the low-voltage DC power and store energy.

4. The multi-feed brushless generator system according to claim 1, characterized in that, The control module includes: The medium-voltage DC output voltage control module is used to calculate the difference between the reference value and the feedback value of the medium-voltage DC power, and then, through PI control, obtain the control winding current. Axis component reference values; The control winding frequency calculation module is used to obtain the frequency of the control winding based on the rotational speed of the multi-feed brushless generator, the rated frequency of the medium-voltage power winding, and the rated frequency of the low-voltage power winding. A control winding frequency integrator is used to integrate the frequency of the control winding to obtain a reference angle. A control winding current conversion module is used to convert the current on the control winding side according to the reference angle. Phase current is converted into control winding current. Shaft component feedback value and Shaft component feedback value; The winding current control module is used to control the winding current. Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; will control the winding current. Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; the control winding current The reference value for the axis component is zero; A control winding voltage conversion module is used to convert the control winding voltage according to the reference angle. Shaft component reference values ​​and Shaft component reference value transformed into control winding voltage Shaft component reference values ​​and Axis component reference values; A control winding SVPWM generator is used to control the winding voltage. Shaft component reference values ​​and The axis component reference value generates the first PWM pulse modulation signal.

5. The multi-feed brushless generator system according to claim 1, characterized in that, The control module also includes: The low-voltage DC output voltage control module is used to obtain the low-voltage power winding current by subtracting the reference value and feedback value of the low-voltage DC power supply and then controlling it via PI control. Axis component reference values; A low-voltage power winding voltage phase-locked loop is used to obtain the voltage phase based on the three-phase voltage on the low-voltage power winding side; A low-voltage power winding current conversion module is used to convert the current of the low-voltage power winding side according to the voltage phase. Phase current is converted into low-voltage power winding current. Shaft component feedback value and Shaft component feedback value; The low-voltage power winding current control module is used to control the low-voltage power winding current. After subtracting the shaft component reference value from the feedback value, the low-voltage power winding voltage is obtained through PI control. Shaft component reference value; The low-voltage power winding current... The difference between the shaft component reference value and the feedback value is used to obtain the low-voltage power winding voltage via PI control. Shaft component reference value; low-voltage power winding current The reference value for the axis component is zero; A low-voltage power winding voltage conversion module is used to convert the low-voltage power winding voltage according to the voltage phase. Shaft component reference values ​​and The shaft component reference value is transformed into the low-voltage power winding voltage. Shaft component reference values ​​and Axis component reference values; Low-voltage controlled rectifier SVPWM generator, used to generate a low-voltage power winding voltage. Shaft component reference values ​​and The axis component reference value is used to generate the second PWM pulse modulation signal.

6. A control method based on the multi-feed brushless generator system of claim 1, characterized in that, The control method includes: According to the first PWM pulse modulation signal, excitation current is provided to the control winding side of the multi-feed brushless generator; The multi-feed brushless generator outputs medium-voltage AC power on the medium-voltage power winding side and low-voltage AC power on the low-voltage power winding side according to the excitation current. Convert the medium-voltage AC power output from the medium-voltage power winding side of the multi-feed brushless generator into medium-voltage DC power; The low-voltage AC power output from the low-voltage power winding side of the multi-feed brushless generator is converted into low-voltage DC power according to the second PWM pulse modulation signal. The first PWM pulse modulation signal and the second PWM pulse modulation signal are generated based on the low-voltage DC and medium-voltage DC.

7. The control method according to claim 6, characterized in that, The first PWM pulse modulation signal is obtained through the following method: The difference between the reference value and the feedback value of the medium-voltage DC current is used to obtain the control winding current through PI control. Axis component reference values; The frequency of the control winding is obtained based on the rotational speed of the multi-feed brushless generator, the rated frequency of the medium-voltage power winding, and the rated frequency of the low-voltage power winding. The reference angle is obtained by integrating the frequency of the control winding; Based on the reference angle, the control winding side will be... Phase current is converted into control winding current. Shaft component feedback value and Shaft component feedback value; Control the winding current Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Axis component reference values; Control the winding current Shaft component reference value and After subtracting the shaft component feedback values, the control winding voltage is obtained through PI control. Shaft component reference value; the control winding current The reference value for the axis component is zero; Based on the aforementioned reference angle, the control winding voltage will be... Shaft component reference values ​​and Shaft component reference value transformed into control winding voltage Shaft component reference values ​​and Axis component reference values; According to the control winding voltage Shaft component reference values ​​and The axis component reference value generates the first PWM pulse modulation signal.

8. The control method according to claim 6, characterized in that, The second PWM pulse modulation signal is obtained through the following method: The difference between the reference value and the feedback value of the low-voltage DC current is calculated, and then the low-voltage power winding current is obtained through PI control. Axis component reference values; The voltage phase is obtained from the three-phase voltage on the low-voltage power winding side; Based on the voltage phase, the low-voltage power winding side Phase current is converted into low-voltage power winding current. Shaft component feedback value and Shaft component feedback value; The low-voltage power winding current After subtracting the shaft component reference value from the feedback value, the low-voltage power winding voltage is obtained through PI control. Shaft component reference value; The low-voltage power winding current... The difference between the shaft component reference value and the feedback value is used to obtain the low-voltage power winding voltage via PI control. Shaft component reference value; low-voltage power winding current The reference value for the axis component is zero; Based on the voltage phase, the low-voltage power winding voltage... Shaft component reference values ​​and The shaft component reference value is transformed into the low-voltage power winding voltage. Shaft component reference values ​​and Axis component reference values; Low-voltage controlled rectifier SVPWM generator, used to generate a low-voltage power winding voltage. Shaft component reference values ​​and The axis component reference value is used to generate the second PWM pulse modulation signal.

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