Control device and integrated control method for high-rotating-speed switched reluctance starter generator

Abstract

The invention discloses a control device for a high-rotating-speed switched reluctance starter generator and an integrated control method. The control device comprises a main power circuit and a control circuit, wherein the main power circuit comprises a starting soft power-on circuit, a permanent magnet machine rectifying circuit, a permanent magnet machine soft power-on circuit, a dual three-phase asymmetric half-bridge circuit, a bleeder circuit and a drive circuit; the starting soft power-on circuit is connected to the dual three-phase asymmetric half-bridge circuit through the bleeder circuit; the permanent magnet machine rectification circuit is connected to the dual three-phase asymmetric half-bridge circuit through the permanent magnet machine soft power-on circuit and the bleeder circuit. The input end of the driving circuit is connected to the control circuit, the output end of the driving circuit is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is further connected to a starting soft power-on circuit in the main power circuit, a permanent magnet machine rectifying circuit, a permanent magnet machine soft power-on circuit and a contactor and a relay in the bleeder circuit; and the control device of the switched reluctance starter generator is used for controlling the connection and disconnection of each contactor and relay in the main power circuit through the control circuit and controlling the dual three-phase asymmetric half-bridge circuit so as to realize the integrated control of starting and power generation of the switched reluctance starter generator. According to the technical scheme of the invention, the problems that the research of the existing switched reluctance motor is generally concentrated at low rotating speed and medium and small power, and the research and engineering application practice of the high-power and high-rotating-speed switched reluctance generator are not blank yet are solved.

Description

Technical Field

[0001] The present invention relates to the field of, but is not limited to, aviation switched reluctance motor control technology, and in particular to a control device and an integrated control method for a high-speed switched reluctance starter generator. Background Art

[0002] According to the development trend of all-electric / more-electric aircraft in the future, high-voltage DC starting / generation technology has been developed to meet the demand for power supply systems in the aviation field, such as the motor speed and maximum power being limited by the DC motor brushes and commutator, the heavy weight and inconvenient installation of the low-voltage DC grid when transmitting high power, and the increase in the volume and weight of the secondary power supply due to the increase in AC power equipment.

[0003] In response to the electric starting requirements of the next generation of aircraft high-thrust turbofan engines, high-power and high-speed power generation, and the requirements for built-in engine starting / power generation, as well as the future aircraft's demand for robust power supply systems, the traditional wound rotor motor has rotating diodes and other equipment, and its speed and power are limited; while the permanent magnet motor is expensive and difficult to demagnetize during power generation. Considering that the switched reluctance SR motor has good high temperature resistance and is suitable for high-speed operation due to the lack of windings and permanent magnets in the rotor, it is easy to achieve large capacity and dual functions of starting and power generation.

[0004] At present, Nanjing University of Aeronautics and Astronautics and Northwestern Polytechnical University have conducted feasibility studies on the application of SR starter / generator systems in aviation. In terms of basic theory, they have conducted special studies on starting characteristics and power generation quality, strong excitation topology circuits, power generation control strategies, and rotor position sensorless technology control strategies. In engineering practice, Nanjing University of Aeronautics and Astronautics has developed two sets of 3kW and 6kW principle prototypes. The motors are air-cooled, and the existing research and application of switched reluctance motors are mainly focused on the running state of the motors, and are all concentrated on low speed and small and medium power. There is currently very little research on switched reluctance motors in terms of high power, and no engineering application practice has been achieved. Summary of the invention

[0005] Purpose of the present invention: In order to solve the above-mentioned technical problems, the embodiments of the present invention provide a control device and an integrated control method for a high-speed switched reluctance starter generator, so as to solve the problem that the research on existing switched reluctance motors generally focuses on low speed and medium and small power, and there is still a lack of research and engineering application practice on high-power and high-speed switched reluctance generators.

[0006] Technical solution of the present invention: In a first aspect, an embodiment of the present invention provides a control device for a high-power and high-speed switched reluctance starter generator, characterized in that it includes: a main power circuit and a control circuit;

[0007] Wherein, the main power circuit includes: a starting soft power-on circuit, a permanent magnet machine rectifier circuit, a permanent magnet machine soft power-on circuit, a dual three-phase asymmetric half-bridge circuit, a discharge circuit and a drive circuit; the starting soft power-on circuit is connected to the dual three-phase asymmetric half-bridge circuit through the discharge circuit; the permanent magnet machine rectifier circuit is connected to the dual three-phase asymmetric half-bridge circuit through the permanent magnet machine soft power-on circuit and the discharge circuit; the input end of the drive circuit is connected to the control circuit, and the output end is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is also connected to the contactors and relays in the starting soft power-on circuit, the permanent magnet machine rectifier circuit, the permanent magnet machine soft power-on circuit and the discharge circuit in the main power circuit;

[0008] The control device of the switched reluctance starter generator is used to control the connection and disconnection of each contactor and relay in the main power circuit through the control circuit, and control the dual three-phase asymmetric half-bridge circuit, so as to realize the integrated control of starting and power generation of the switched reluctance starter generator.

[0009] Optionally, in the control device for a high-power and high-speed switched reluctance starter generator as described above, the dual three-phase asymmetric half-bridge circuit adopts a dual-channel three-phase asymmetric half-bridge structure, including: a busbar support capacitor, an output filter capacitor and a power generation diode, and two groups of power IGBT modules;

[0010] Among them, the busbar support capacitor is connected between the starting busbar and the power negative line, and is located at the front end of the dual three-phase asymmetric half-bridge circuit, and the output filter capacitor is connected between the power generation output busbar and the power negative line, and is located at the rear end of the dual three-phase asymmetric half-bridge circuit; in each group of power IGBT modules, three IGBT bridge arms arranged at intervals are connected between the starting busbar and the power negative line (to form three-phase positive electricity), and another three IGBT bridge arms arranged at intervals are connected between the power generation output busbar and the power negative line (to form three-phase negative electricity), and three groups of IGBT bridge arms are combined to form three groups of IGBT bridge arms, so as to output the three-phase current of the generator through the three groups of IGBT bridge arms;

[0011] The positive pole of the power generation diode is connected to the power generation output bus, and the negative pole is connected to the starting bus. The power generation diode is located on the side of the output bus close to the excitation side to transmit the current generated by the generator to the excitation side.

[0012] Optionally, in the control device for a high-power and high-speed switched reluctance starter generator as described above,

[0013] The starting soft power-on circuit comprises: a series branch of a resistor and a starting soft power-on relay, and a starting soft power-on contactor connected in parallel with the series branch; the input end of the starting soft power-on circuit is connected to the power supply through the soft start relay and the starting contactor, and the output end is connected to the starting bus and the discharge circuit;

[0014] The starting soft power-on circuit is used to limit the charging current of the bus support capacitor at the power-on moment to reduce the impact on the power supply and the bus support capacitor; it is also used to connect the starting soft power-on contactor under the control of the control circuit after the bus support capacitor is charged, so that the control device enters a normal operating state.

[0015] Optionally, in the control device for a high-power and high-speed switched reluctance starter generator as described above,

[0016] The permanent magnet machine rectification circuit comprises a GCR relay and an uncontrolled rectifier bridge connected in series, the input end of the power generation relay is connected to the permanent magnet machine, and the output end of the uncontrolled rectifier bridge is respectively connected to the permanent magnet machine soft power-on circuit and the discharge circuit; the permanent magnet machine rectification circuit is used to rectify the three-phase alternating current output by the permanent magnet machine into direct current, and control whether the direct current is connected to the back-end circuit through the GCR relay;

[0017] The permanent magnet machine soft power-on circuit includes a power generation soft power-on relay and a current limiting resistor connected in parallel, an input end of which is connected to an output end of an uncontrolled rectifier bridge, and an output end of which is connected to a starting bus; the permanent magnet machine soft power-on circuit is used to realize soft power-on in the initial stage of power generation during the initial excitation and voltage building stage of the power generation stage.

[0018] Optionally, in the control device for a high-power and high-speed switched reluctance starter generator as described above,

[0019] The discharge circuit includes a discharge relay and a discharge resistor connected in series; the discharge relay is also connected to the starting bus, and the discharge resistor is connected to the other output end of the uncontrolled rectifier bridge; the discharge circuit is used to quickly discharge the voltage on the starting bus in a short time when the starting is terminated and the power generation is terminated.

[0020] Optionally, in the control device for a high-power and high-speed switched reluctance starter generator as described above, the control circuit comprises: a DSP chip, a CPLD chip and a resolver decoding chip connected in pairs; the CPLD chip is connected to the drive circuit, and the DSP chip is connected to each contactor and relay in the main power circuit;

[0021] The resolver decoding chip is used to resolve the motor rotor position signal, and the motor rotor position signal is collected by the DSP chip and the CPLD chip; the DSP chip is used to calculate the initial position of the motor and send it to the CPLD chip, and the CPLD chip counts the incremental encoding signal of the motor rotor position signal based on the initial position of the motor; the DSP chip is also used to calculate the motor speed according to the received position signal, and send a control signal of the drive circuit to the CPLD chip based on the speed calculation result, so as to control the drive circuit to realize the functional control of the power IGBT module in the dual three-phase asymmetric half-bridge circuit;

[0022] The DSP chip is also connected to the main power circuit through the acquisition circuit, and controls the on and off of each relay and contactor by acquiring the voltage signal in the main power circuit.

[0023] In the second aspect, an embodiment of the present invention also provides an integrated control method for a high-power and high-speed switched reluctance starter generator, which uses a control device for a high-power and high-speed switched reluctance starter generator as described in any of the above items to execute an integrated control method for the high-power and high-speed switched reluctance starter generator, including: starting control, power generation control; wherein the starting control includes starting soft power-on control and generator starting control in the initial stage of starting, and the power generation control includes soft power-on and voltage building control in the initial stage of power generation and control of the power generation process.

[0024] Optionally, in the integrated control method of a high-power and high-speed switched reluctance starter generator as described above, the starting control method includes:

[0025] First, turn on the starting soft power-on relay to reduce the impact of the busbar support capacitor at the moment of power-on through the current limiting function of the resistor and the starting soft power-on relay;

[0026] When the voltage of the busbar support capacitor on the starting busbar is greater than 190V, the starting soft power-on contactor is turned on and the starting soft power-on relay is turned off to achieve fast charging and complete the soft power-on of the starting power supply;

[0027] The starting control strategy pre-configured in the control circuit is adopted. The dual three-phase asymmetric half-bridge circuit is controlled by the drive circuit. According to the motor rotor position and the set turn-on angle and turn-off angle, the power IGBT module is driven by the drive circuit to convert the 270V DC starting power supply into the three-phase power supply required by the motor, generate power torque, and drive the engine to start.

[0028] Optionally, in the above-mentioned integrated control method for a high-power and high-speed switched reluctance starter generator, the power generation control method includes:

[0029] First, turn on the GCR relay. When the voltage on the starting bus is greater than 140V, turn on the generator soft power-on relay.

[0030] Under the action of the external voltage-building excitation power source passed through the permanent magnet machine, the busbar support capacitor is charged after passing through the current-limiting resistor, and the permanent magnet machine outputs a DC voltage after passing through the uncontrolled rectifier bridge of the permanent magnet machine rectifier circuit, completing the power generation and voltage-building process;

[0031] After the voltage is built up, the power generation control strategy pre-configured in the control circuit is adopted to control the dual three-phase asymmetric half-bridge circuit through the drive circuit to complete the power generation voltage regulation and stably output 270V DC power supply;

[0032] When the motor speed reaches the grid-connected speed, and the generating voltage regulation meets (270±5)V and is stable for 1s, the generating contactor connected in parallel at the rear end of the output filter capacitor is controlled to be connected to realize the grid-connected generation; when the motor speed is lower than the grid-connected speed, the dual three-phase asymmetric half-bridge circuit is controlled to stop the output of the power IGBT module, and the generating contactor is controlled to be disconnected to realize grid withdrawal.

[0033] Beneficial effects of the present invention: An embodiment of the present invention provides a control device and an integrated control method for a high-speed switched reluctance starter generator, wherein the control device comprises two circuits, namely a main power circuit and a control circuit. In the main power circuit, a starting soft power-on circuit is connected to a dual three-phase asymmetric half-bridge circuit through a discharge circuit; a permanent magnet machine rectifier circuit is connected to a dual three-phase asymmetric half-bridge circuit through a permanent magnet machine soft power-on circuit and a discharge circuit; an input end of a drive circuit is connected to a control circuit, and an output end is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is also connected to each contactor and relay in the main power circuit; the control device realizes integrated control of starting and power generation of the switched reluctance starter generator by controlling the connection and disconnection of each contactor and relay in the main power circuit and controlling the dual three-phase asymmetric half-bridge circuit through the control circuit. The control device and control strategy for a high-speed switched reluctance starter generator provided in an embodiment of the present invention are adopted. For the switched reluctance starter generator, the control device is adopted to complete the mode conversion of the switched reluctance starter generator through mode conversion, thereby realizing the integration of starting and power generation; the soft starting process, the soft voltage building process of power generation, and the process of converting power generation from external excitation to self-excitation are realized through the control strategy of the control circuit. This method has the advantages of keeping the excitation voltage relatively stable during external excitation, while reducing the weight of the system in the self-excitation mode, thereby improving the system efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0035] Figure 1 A circuit block diagram of a control device for a high-power and high-speed switched reluctance starter generator provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of the circuit structure of a control device for a high-power and high-speed switched reluctance starter generator provided by an embodiment of the present invention;

[0037] Figure 3 A flow chart of the start control performed by the control device for the high-power and high-speed switched reluctance starter generator provided by the embodiment of the present invention;

[0038] Figure 4 A flow chart of power generation control performed by a control device for a high-power and high-speed switched reluctance starter generator provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0040] As explained in the above background technology, based on the characteristics and high temperature resistance of the switched reluctance SR motor, it is easy to achieve large capacity and dual functions of starting and generating; however, the existing research and application of the switched reluctance motor is mainly focused on the running state of the motor, and all are concentrated on low speed and medium and small power. There is currently very little research on the high power of the switched reluctance motor, and no engineering application practice has been achieved.

[0041] In order to make the switched reluctance motor suitable for high-power and high-speed starting engines, the present invention designs a control device and a corresponding integrated control method for the high-power and high-speed switched reluctance starter generator, and specifically provides a control device and an integrated control method for a high-speed switched reluctance starter generator, which have good application prospects in the aviation field.

[0042] The present invention provides the following specific embodiments which can be combined with each other. The same or similar concepts or processes may not be described in detail in some embodiments.

[0043] Figure 1 The circuit block diagram of a control device for a high-power and high-speed switched reluctance starter generator provided by an embodiment of the present invention. Figure 1 As shown, the main components of the control device of the switched reluctance starter generator provided by the embodiment of the present invention include: a main power circuit and a control circuit.

[0044] like Figure 1 As shown, the main power circuit includes: a starting soft power-on circuit, a permanent magnet machine rectifier circuit, a permanent magnet machine soft power-on circuit, a dual three-phase asymmetric half-bridge circuit, a discharge circuit and a drive circuit; wherein the starting soft power-on circuit is connected to the dual three-phase asymmetric half-bridge circuit through the discharge circuit; the permanent magnet machine rectifier circuit is connected to the dual three-phase asymmetric half-bridge circuit through the permanent magnet machine soft power-on circuit and the discharge circuit; the input end of the drive circuit is connected to the control circuit, and the output end is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is also connected to the contactors and relays in the starting soft power-on circuit, the permanent magnet machine rectifier circuit, the permanent magnet machine soft power-on circuit and the discharge circuit in the main power circuit.

[0045] The control device of the switched reluctance starter generator in the embodiment of the present invention is used to control the connection and disconnection of each contactor and relay in the main power circuit through the control circuit, and control the dual three-phase asymmetric half-bridge circuit, so as to realize the integrated control of starting and power generation of the switched reluctance starter generator.

[0046] The specific structure of each circuit in the control device of the switched reluctance starter generator provided by the embodiment of the present invention is described below.

[0047] (I) Main power circuit

[0048] like Figure 2 , which is a schematic diagram of the circuit structure of a control device for a high-power and high-speed switched reluctance starter generator provided by an embodiment of the present invention.

[0049] 1.1, the dual three-phase asymmetric half-bridge circuit includes: power IGBT module, bus support capacitor, output filter capacitor and power generation diode. The IGBT module is used to build a three-phase asymmetric half-bridge circuit. Each phase winding is connected to two IGBTs and two freewheeling diodes, which can realize independent control of the three-phase winding of the stator, and there is no bridge arm direct-through phenomenon. Since the current flowing through the switching device is large when a single-channel three-phase asymmetric half-bridge topology is adopted, and in order to achieve redundant control, a dual-channel three-phase asymmetric half-bridge topology is adopted. The power generation diode is used to connect the starting bus and the power output bus. The bus support capacitor is connected between the starting bus and the power negative line and is located at the front end of the circuit. The bus support capacitor is used to stabilize the starting bus current and maintain the starting bus voltage during the starting stage. The output filter capacitor is connected between the starting bus and the power negative line and is located at the end of the three-phase asymmetric half-bridge circuit. The output filter capacitor is used to perform power filtering on the output pulsating voltage and output a 270VDC power supply that meets the quality.

[0050] In a specific implementation, the dual-channel three-phase asymmetric half-bridge topology may include: two groups of power IGBT modules, such as Figure 2 As shown, in each group of power IGBT modules, three spaced-apart IGBT bridge arms are connected between the starting bus and the power negative line (to form three-phase positive electricity), and another three spaced-apart IGBT bridge arms are connected between the generator output bus and the power negative line (to form three-phase negative electricity), which are combined to form three groups of IGBT bridge arms to output the three-phase current of the generator through the three groups of IGBT bridge arms.

[0051] 1.2, the starting soft power-on circuit includes a series branch of a resistor and a starting soft power-on relay, and a starting soft power-on contact connected in parallel with the above series branch; the input end of the starting soft power-on circuit is connected to the power supply through the soft start relay and the starting contactor, and the output end is connected to the starting bus and the discharge circuit. Since the bus support capacitor is charged very quickly at the moment of power-on, in order to reduce the impact of the support capacitor at the moment of power-on and improve the reliability and safety of the product, the charging current of the bus support capacitor needs to be limited when power is on, thereby reducing the impact on the power supply and the bus support capacitor, and protecting the capacitor and the power supply circuit. When the bus support capacitor is charged, the control circuit sends a connection signal to control the starting soft power-on contactor to turn on, and the control device enters normal operating state.

[0052] It should be noted that the connection form of the soft start relay and the starting contactor is similar to the connection form of the starting soft power-on relay and the starting soft power-on contactor, such as Figure 1 As shown, a resistor is connected in series with the soft-start relay, and the whole is connected in parallel with the starting contactor.

[0053] 1.3, the permanent magnet machine rectifier circuit includes a generator relay (GCR relay) and an uncontrolled rectifier bridge connected in series, the input end of the GCR relay is connected to the permanent magnet machine, and the output end of the uncontrolled rectifier bridge is connected to the permanent magnet machine soft power-on circuit and the discharge circuit respectively. The three-phase AC output of the permanent magnet machine is rectified into DC, and its GCR relay is controlled by the control circuit to control whether the DC is connected to the back end.

[0054] 1.4, the permanent magnet machine soft power-on circuit includes a power generation soft power-on relay and a current limiting resistor connected in parallel, its input end is connected to an output end of the uncontrolled rectifier bridge, and its output end is connected to the starting bus. The front-end permanent magnet machine is mainly used as the initial excitation and voltage building stage of the power generation stage. Since the excitation power is small and the working time is short in the excitation and voltage building stage, a permanent magnet machine soft power-on circuit with a power generation soft power-on relay and a current limiting resistor connected in parallel is selected to realize soft power-on in the initial stage of power generation.

[0055] 1.5, the discharge circuit includes a discharge relay and a discharge resistor connected in series; the discharge relay is also connected to the starting bus, and the discharge resistor is connected to the other output end of the uncontrolled rectifier bridge, which is mainly used to quickly discharge the voltage in a short time when the starting and power generation are terminated.

[0056] (ii) Control circuit

[0057] like Figure 1 As shown, the control circuit includes: a DSP chip, a CPLD chip and a resolver decoding chip connected in pairs; the CPLD chip is connected to the drive circuit, and the DSP chip is connected to each contactor and relay in the main power circuit. Its functions mainly include position resolution function, starting control function, and power generation control function.

[0058] The resolver decoding chip is used to resolve the motor rotor position signal, and the DSP chip and the CPLD chip simultaneously collect the generator rotor position signal. The resolver decoding chip feeds back the resolved motor rotor position signal to the DSP chip through the data bus for speed calculation and other data resolution, and sends the motor initial position to the CPLD chip through the data bus between the CPLD chip and the CPLD chip. The CPLD chip counts the incremental encoding signal of the motor rotor position resolution based on the motor initial position. The DSP chip calculates the motor speed according to the received position signal, and sends the control signal of the drive circuit to the CPLD chip based on the speed calculation result to control the drive circuit to realize the functional control of the power IGBT module of the dual three-phase asymmetric half-bridge circuit. In addition, the DSP chip is also connected to the main power circuit through the acquisition circuit, and realizes the control of the connection and disconnection of each relay and contactor by collecting the voltage signal in the main power circuit. The starting control function and the power generation control function are realized by controlling the switch of each relay and contactor in the main power circuit and the control of the dual three-phase asymmetric half-bridge circuit.

[0059] The working process of the control device of the switched reluctance starter generator provided by the above embodiment of the present invention is described as follows:

[0060] When the switched reluctance starter generator enters the starting state, the starting control process is as follows: to avoid the current impact of the starting power supply on the control device when the power is on, first turn on the starting soft power-on relay. Since the starting soft power-on relay is connected in series with the resistor, it can effectively reduce the impact of the bus support capacitor at the moment of power-on. When the voltage of the bus support capacitor on the starting bus is greater than 190V, turn on the starting soft power-on contactor and disconnect the starting soft power-on relay to achieve fast charging and complete the soft power-on of the starting power supply; then, the starting control strategy pre-configured in the DSP chip of the control circuit is used to control the dual three-phase asymmetric half-bridge circuit through the drive circuit. According to the motor rotor position and the set turn-on angle and turn-off angle, the six IGBT bridge arms are driven by the drive circuit to convert the 270V DC starting power supply into the three-phase power supply required by the motor, generate power torque, and drive the engine to start; the rotor position signal required during the starting process is provided by the motor.

[0061] The power generation control process is as follows: First, turn on the GCR relay. When the voltage on the starting bus is greater than 140V, turn on the power generation soft power-on relay. Under the action of the external voltage-building excitation power supply passed by the permanent magnet machine, the bus support capacitor is charged after the current limiting resistor. The permanent magnet machine outputs a DC voltage after the uncontrolled rectifier bridge of the permanent magnet machine rectifier circuit to complete the power generation voltage building process. After the voltage is built, the power generation control strategy pre-configured in the control circuit is adopted to control the dual three-phase asymmetric half-bridge circuit through the drive circuit to complete the power generation voltage regulation and stably output 270V DC power supply (power generation output + / -). When the motor speed reaches the grid-connected speed, and the power generation voltage regulation voltage meets (270±5)V, and is stable for 1s, the power generation contactor connected in parallel at the rear end of the output filter capacitor is controlled to be connected to realize power generation grid connection. When the motor speed is lower than the grid-connected speed, the control device stops the output of the power IGBT module and controls the power generation contactor to be disconnected to realize grid withdrawal.

[0062] It should be noted that the switched reluctance starter generator adopts two feedback power generation working modes: self-excitation and external excitation during power generation operation. The external excitation mode is that at the initial moment of voltage establishment, the power supply of the external permanent magnet machine provides initial excitation. The self-excitation mode means that after the voltage is built up, the power supply voltage provides its own excitation power, converts mechanical energy into electrical energy output, and the power generation diode allows the current to flow only from the power generation side to the excitation side. When the voltage is established, the external excitation power supply is disconnected, and the output filter capacitor provides excitation energy to achieve system self-excitation.

[0063] An embodiment of the present invention provides a control device and an integrated control method for a high-speed switched reluctance starter generator. The control device includes two circuits: a main power circuit and a control circuit. In the main power circuit, a starting soft power-on circuit is connected to a dual three-phase asymmetric half-bridge circuit through a discharge circuit; a permanent magnet machine rectifier circuit is connected to the dual three-phase asymmetric half-bridge circuit through a permanent magnet machine soft power-on circuit and a discharge circuit; an input end of a drive circuit is connected to a control circuit, and an output end is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is also connected to each contactor and relay in the main power circuit; the control device controls the connection and disconnection of each contactor and relay in the main power circuit and the dual three-phase asymmetric half-bridge circuit through the control circuit, thereby realizing integrated control of starting and power generation of the switched reluctance starter generator. The control device and control strategy for a high-speed switched reluctance starter generator provided in an embodiment of the present invention are adopted. For the switched reluctance starter generator, the control device is adopted to complete the mode conversion of the switched reluctance starter generator through mode conversion, thereby realizing the integration of starting and power generation; the soft starting process, the soft voltage building process of power generation, and the process of converting power generation from external excitation to self-excitation are realized through the control strategy of the control circuit. This method has the advantages of keeping the excitation voltage relatively stable during external excitation, while reducing the weight of the system in the self-excitation mode, thereby improving the system efficiency.

[0064] The following describes the starting control process and the power generation control process of the control device and the integrated control method for a high-power and high-speed switched reluctance starter generator provided by the embodiments of the present invention through several implementation examples.

[0065] Implementation Example 1

[0066] like Figure 3 As shown, it is a flowchart of the start control performed by the control device for high-power and high-speed switched reluctance starter generator provided by the embodiment of the present invention. The start control process provided by the implementation example 1 includes the following steps:

[0067] 1) When the start command is valid and the motor rotor speed is less than 7200r / min, it enters the start mode.

[0068] 2) After entering the starting mode, first control the soft start relay to turn on; after a delay of 500ms, control the starting contactor to turn on; after detecting that the auxiliary contact of the starting contactor is turned on, control the soft start relay to turn off and turn on the starting soft power-on relay; when the starting bus voltage is greater than or equal to 190V, after confirming for 200ms, control the starting soft power-on contactor to close; after a delay of 30ms, control the starting soft power-on relay and the soft start relay to turn off, and complete the starting soft power-on control. During the soft power-on process, the bus current does not exceed 200A, and the soft power-on time does not exceed 3s.

[0069] 3) Then, the control circuit controls the motor winding current, on / off interval and other variables through the drive circuit according to the starting control strategy, outputs the drive signal, converts the 270V DC power into the three-phase power required by the motor, generates power torque, controls the motor to drive the engine to rotate, and completes the engine starting control.

[0070] 4) The starting control strategy in this implementation example 1 is:

[0071] a) Control the given current: Set 4 speed sections, starting speed 1, starting speed 2, starting speed 3, and starting speed 4, and set different given current values ​​according to different starting speed sections. When the motor speed is less than or equal to starting speed 1, if the given current value is less than the given current limit 1, the given current value = given current + 10, otherwise the given current = given current limit 1; when the motor speed is greater than starting speed 1 and less than or equal to starting speed 2, the given current value increases to the given current limit 2 according to the given curve; when the motor speed is greater than starting speed 2 and less than or equal to starting speed 3, the given current increases to the given current limit 3 according to the given curve; when the motor speed is greater than starting speed 3, the given current value = (starting speed 3 / current speed) * given current limit 3, if the given current value is greater than the given current limit 3, then the given current value = given current limit 3, if the given current value is greater than the given current limit 4, then the given current value = given current limit 4.

[0072] b) Control the opening angle and closing angle: set 3 speed sections, angle speed 1, angle speed 2, angle speed 3,

[0073] When the speed is less than angle speed 1, set the opening angle 1 and the closing angle 1; when the speed is greater than or equal to angle speed 1 and less than angle speed 2, set the opening angle 2 and the closing angle 2; when the speed is greater than or equal to angle speed 2 and less than angle speed 3, set the opening angle 3 and the closing angle 3; when the speed is greater than angle speed 3, set the opening angle 4 and the closing angle 4.

[0074] like Figure 3 As shown, the start-stop process also provided in this implementation example 1 includes the following steps:

[0075] 1) When the starting command is invalid or the speed is greater than 7200r / min or a starting failure occurs, disconnect the starting contactor and the starting soft power-on contactor.

[0076] 2) Turn on the discharge relay. When the starting bus voltage is lower than 5V and the discharge relay control signal is on, the discharge relay is disconnected after a delay of 1s; when the starting bus voltage is greater than 5V and the discharge relay control signal is on, the discharge relay is disconnected after a delay of 20s.

[0077] Implementation Example 2

[0078] like Figure 4 As shown, it is a flow chart of the control device for high-power and high-speed switched reluctance starter generator provided by the embodiment of the present invention to perform power generation control. The power generation control process provided by this embodiment 2 includes the following steps:

[0079] 1) When the GCS command is valid and the speed is greater than 20000r / min, it switches to power generation mode.

[0080] 2) First, control the GCR relay to turn on; when the starting bus voltage value is greater than or equal to 140V, and after a delay of 20ms, turn on the power generation soft power-on relay to complete the power generation soft power-on control; when the motor rotor speed reaches the voltage building speed, the control device controls the motor to realize the power generation voltage building function. During the voltage building process, the given voltage increases by 10V every 30ms until it increases to 270V, realizing the soft voltage building function; when the motor speed reaches the grid speed of 22000r / min, and the power generation voltage regulation voltage is greater than or equal to 270V, after stabilizing for 50ms, turn on the power generation contactor connected in parallel to the rear end of the output filter capacitor.

[0081] 3) After a delay of 30ms, the GCR relay is controlled to disconnect from the power generation soft power-on relay, and the power generation is put into the grid. The current flows from the power generation side to the excitation side through the power generation diode, thereby realizing self-excitation.

[0082] 4) In the power generation mode, the control circuit adjusts the voltage through a pre-configured power generation control strategy so that the output voltage is within the regulation requirement range.

[0083] 5) The power generation control strategy in this implementation example 2 is: adopt voltage closed-loop control. Calculate the difference between the given voltage regulation voltage and the actual voltage regulation voltage, output a given current through PI regulation, perform excitation control on the motor winding, and realize closed-loop control.

[0084] like Figure 4 As shown, the power generation termination process also provided in this implementation example 2 includes the following steps:

[0085] 1) When the GCS command is invalid or the speed is less than 20000r / min or a generator failure occurs, if the generator contactor is connected, the generator contactor, GCR relay and generator soft power-on relay are controlled to be disconnected.

[0086] 2) Turn on the discharge relay. When the starting bus voltage is lower than 5V and the discharge relay control signal is on, the discharge relay is disconnected after a delay of 1s; when the starting bus voltage is greater than 5V and the discharge relay control signal is on, the discharge relay is disconnected after a delay of 20s.

[0087] Although the embodiments disclosed in the present invention are as above, the contents are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A control device for a high-power and high-speed switched reluctance starter generator, characterized in that: include: Main power circuit and control circuit; Wherein, the main power circuit includes: a starting soft power-on circuit, a permanent magnet machine rectifier circuit, a permanent magnet machine soft power-on circuit, a dual three-phase asymmetric half-bridge circuit, a discharge circuit and a drive circuit; the starting soft power-on circuit is connected to the dual three-phase asymmetric half-bridge circuit through the discharge circuit; the permanent magnet machine rectifier circuit is connected to the dual three-phase asymmetric half-bridge circuit through the permanent magnet machine soft power-on circuit and the discharge circuit; the input end of the drive circuit is connected to the control circuit, and the output end is connected to each IGBT tube in the dual three-phase asymmetric half-bridge circuit, and the control circuit is also connected to the contactors and relays in the starting soft power-on circuit, the permanent magnet machine rectifier circuit, the permanent magnet machine soft power-on circuit and the discharge circuit in the main power circuit; The control device of the switched reluctance starter generator is used to control the connection and disconnection of each contactor and relay in the main power circuit through the control circuit, and control the dual three-phase asymmetric half-bridge circuit, so as to realize the integrated control of starting and power generation of the switched reluctance starter generator.

2. The control device for a high-power and high-speed switched reluctance starter generator according to claim 1, characterized in that: The dual three-phase asymmetric half-bridge circuit adopts a dual-channel three-phase asymmetric half-bridge structure, including: a busbar support capacitor, an output filter capacitor and a power generation diode, and two groups of power IGBT modules; Among them, the busbar support capacitor is connected between the starting busbar and the power negative line, and is located at the front end of the dual three-phase asymmetric half-bridge circuit, and the output filter capacitor is connected between the power generation output busbar and the power negative line, and is located at the rear end of the dual three-phase asymmetric half-bridge circuit; in each group of power IGBT modules, three IGBT bridge arms arranged at intervals are connected between the starting busbar and the power negative line (to form three-phase positive electricity), and another three IGBT bridge arms arranged at intervals are connected between the power generation output busbar and the power negative line (to form three-phase negative electricity), and three groups of IGBT bridge arms are combined to form three groups of IGBT bridge arms, so as to output the three-phase current of the generator through the three groups of IGBT bridge arms; The positive pole of the power generation diode is connected to the power generation output bus, and the negative pole is connected to the starting bus. The power generation diode is located on the side of the output bus close to the excitation side to transmit the current generated by the generator to the excitation side.

3. The control device for a high-power and high-speed switched reluctance starter generator according to claim 2, characterized in that: The starting soft power-on circuit comprises: a series branch of a resistor and a starting soft power-on relay, and a starting soft power-on contactor connected in parallel with the series branch; the input end of the starting soft power-on circuit is connected to the power supply through the soft start relay and the starting contactor, and the output end is connected to the starting bus and the discharge circuit; The starting soft power-on circuit is used to limit the charging current of the bus support capacitor at the power-on moment to reduce the impact on the power supply and the bus support capacitor; it is also used to connect the starting soft power-on contactor under the control of the control circuit after the bus support capacitor is charged, so that the control device enters a normal operating state.

4. The control device for a high-power and high-speed switched reluctance starter generator according to claim 3, characterized in that: The permanent magnet machine rectification circuit comprises a GCR relay and an uncontrolled rectifier bridge connected in series, the input end of the power generation relay is connected to the permanent magnet machine, and the output end of the uncontrolled rectifier bridge is respectively connected to the permanent magnet machine soft power-on circuit and the discharge circuit; the permanent magnet machine rectification circuit is used to rectify the three-phase alternating current output by the permanent magnet machine into direct current, and control whether the direct current is connected to the back-end circuit through the GCR relay; The permanent magnet machine soft power-on circuit includes a power generation soft power-on relay and a current limiting resistor connected in parallel, an input end of which is connected to an output end of an uncontrolled rectifier bridge, and an output end of which is connected to a starting bus; the permanent magnet machine soft power-on circuit is used to realize soft power-on in the initial stage of power generation during the initial excitation and voltage building stage of the power generation stage.

5. The control device for a high-power and high-speed switched reluctance starter generator according to claim 4, characterized in that: The discharge circuit includes a discharge relay and a discharge resistor connected in series; the discharge relay is also connected to the starting bus, and the discharge resistor is connected to the other output end of the uncontrolled rectifier bridge; the discharge circuit is used to quickly discharge the voltage on the starting bus in a short time when the starting is terminated and the power generation is terminated.

6. The control device for a high-power and high-speed switched reluctance starter generator according to any one of claims 1 to 5, characterized in that: The control circuit comprises: a DSP chip, a CPLD chip and a resolver decoding chip connected in pairs; the CPLD chip is connected to the drive circuit, and the DSP chip is connected to each contactor and relay in the main power circuit; The resolver decoding chip is used to resolve the motor rotor position signal, and the motor rotor position signal is collected by the DSP chip and the CPLD chip; the DSP chip is used to calculate the initial position of the motor and send it to the CPLD chip, and the CPLD chip counts the incremental encoding signal of the motor rotor position signal based on the initial position of the motor; the DSP chip is also used to calculate the motor speed according to the received position signal, and send a control signal of the drive circuit to the CPLD chip based on the speed calculation result, so as to control the drive circuit to realize the functional control of the power IGBT module in the dual three-phase asymmetric half-bridge circuit; The DSP chip is also connected to the main power circuit through the acquisition circuit, and controls the on and off of each relay and contactor by acquiring the voltage signal in the main power circuit.

7. An integrated control method for a high-power, high-speed switched reluctance starter generator, characterized in that: A control device for a high-power, high-speed switched reluctance starter generator as described in any one of claims 1 to 6 is used to perform an integrated control method for a high-power, high-speed switched reluctance starter generator, including: starting control and power generation control; wherein the starting control includes starting soft power-on control and generator starting control in the initial stage of starting, and the power generation control includes soft power-on voltage building control and control of the power generation process in the initial stage of power generation.

8. The integrated control method for a high-power and high-speed switched reluctance starter generator according to claim 7, characterized in that: The starting control method includes: First, turn on the starting soft power-on relay to reduce the impact of the busbar support capacitor at the moment of power-on through the current limiting function of the resistor and the starting soft power-on relay; When the voltage of the busbar support capacitor on the starting busbar is greater than 190V, the starting soft power-on contactor is turned on and the starting soft power-on relay is turned off to achieve fast charging and complete the soft power-on of the starting power supply; The starting control strategy pre-configured in the control circuit is adopted. The dual three-phase asymmetric half-bridge circuit is controlled by the drive circuit. According to the motor rotor position and the set turn-on angle and turn-off angle, the power IGBT module is driven by the drive circuit to convert the 270V DC starting power supply into the three-phase power supply required by the motor, generate power torque, and drive the engine to start.

9. The integrated control method of a high-power and high-speed switched reluctance starter generator according to claim 7, characterized in that: The power generation control method includes: First, turn on the GCR relay. When the voltage on the starting bus is greater than 140V, turn on the generator soft power-on relay. Under the action of the external voltage-building excitation power source passed through the permanent magnet machine, the busbar support capacitor is charged after passing through the current-limiting resistor, and the permanent magnet machine outputs a DC voltage after passing through the uncontrolled rectifier bridge of the permanent magnet machine rectifier circuit, completing the power generation and voltage-building process; After the voltage is built up, the power generation control strategy pre-configured in the control circuit is adopted to control the dual three-phase asymmetric half-bridge circuit through the drive circuit to complete the power generation voltage regulation and stably output 270V DC power supply; When the motor speed reaches the grid-connected speed, and the generating voltage regulation meets (270±5)V and is stable for 1s, the generating contactor connected in parallel at the rear end of the output filter capacitor is controlled to be connected to realize the grid-connected generation; when the motor speed is lower than the grid-connected speed, the dual three-phase asymmetric half-bridge circuit is controlled to stop the output of the power IGBT module, and the generating contactor is controlled to be disconnected to realize grid withdrawal.

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