Ring winding structure SRG system output voltage control method

Abstract

The invention relates to the technical field of power generation, in particular to a ring winding structure SRG system output voltage control method, which is realized by adopting the following steps of: 1, improving an existing ring winding structure SRG system, the improved ring winding structure SRG system comprises a direct current voltage source, a direct current-direct current half-bridge circuit, a ring winding structure SRG, a full-bridge power converter, a load resistor and an output capacitor. 2, in the system operation process, the system is controlled as follows: a) the actual rotating speed of the ring winding structure SRG is collected; b) collecting three-phase actual phase current and three-phase actual line current of the ring winding structure SRG; and c) collecting the actual output voltage of the system. The method solves the problems that the output voltage of an existing ring winding structure SRG system is uncontrollable and fluctuates greatly, and is suitable for the ring winding structure SRG system.

Description

Technical Field

[0001] The invention relates to the technical field of power generation, and in particular to an output voltage control method of a toroidal winding structure SRG system. Background Art

[0002] The SRG (Switched Reluctance Generator) system has been developed and applied in the fields of aircraft, hybrid vehicles, electric vehicles, wind power generation, etc. due to its simple and strong structure and low cost. Among various SRG systems, the toroidal winding structure SRG system has the advantage of low copper loss because it integrates AC and DC. Figure 1 As shown, under the existing technical conditions, the toroidal winding structure SRG system includes a DC voltage source V1, a toroidal winding structure SRG, a three-phase uncontrolled rectifier circuit, and a load resistor R1. In this system, the DC voltage source V1 directly provides circulating current and excitation energy to the toroidal winding structure SRG, and the toroidal winding structure SRG outputs a DC voltage through the three-phase uncontrolled rectifier circuit. However, in practical applications, due to the limitations of its own structure, the system has the problem that the output voltage is uncontrollable and fluctuates greatly, which limits its scope of application. Based on this, the present invention proposes an output voltage control method for a toroidal winding structure SRG system. This method applies a full-bridge power converter to a toroidal winding structure SRG system for the first time to solve the problem that the output voltage of the existing toroidal winding structure SRG system is uncontrollable and fluctuates greatly. Summary of the invention

[0003] In order to solve the problem that the output voltage of the existing SRG system with a toroidal winding structure is uncontrollable and fluctuates greatly, the present invention provides an output voltage control method for the SRG system with a toroidal winding structure.

[0004] The present invention is achieved by adopting the following technical solutions:

[0005] A method for controlling output voltage of a toroidal winding structure SRG system is implemented by the following steps:

[0006] Step 1: improving the existing toroidal winding structure SRG system, wherein the improved toroidal winding structure SRG system includes a DC voltage source, a DC-DC half-bridge circuit, a toroidal winding structure SRG, a full-bridge power converter, a load resistor, and an output capacitor;

[0007] The two output ends of the DC voltage source are respectively connected to the two input ends of the DC-DC half-bridge circuit; the two output ends of the DC-DC half-bridge circuit are respectively connected to the two ends of the ring winding of the ring winding structure SRG; the three output ends of the ring winding structure SRG are respectively connected to the three AC ends of the full-bridge power converter; the load resistor and the output capacitor are both connected in parallel to the two DC ends of the full-bridge power converter;

[0008] Step 2: During system operation, the system is controlled as follows:

[0009] a) collecting the actual speed of the ring winding structure SRG, subtracting the actual speed from the set reference speed to obtain a speed difference, sending the speed difference to a speed PI controller, and the speed PI controller outputs the input torque of the ring winding structure SRG according to the speed difference;

[0010] b) Collect the three-phase actual phase current and the three-phase actual line current of the ring winding structure SRG, and calculate the actual circulating current of the ring winding structure SRG according to the collected results; the specific calculation formula is as follows:

[0011]

[0012] Where: I cc Indicates the actual circulating current; i pc Indicates the actual phase current of phase C; i la Indicates the actual line current of phase A; i lb Indicates the actual line current of phase B;

[0013] The actual circulating current is subtracted from the set reference circulating current to obtain a circulating current difference, and the circulating current difference is sent to a circulating current PID controller, and the circulating current PID controller outputs a modulation signal according to the circulating current difference;

[0014] A switching control signal is obtained by PWM modulating the modulation signal and the triangular wave, and the switching control signal is applied to two IGBTs of the DC-DC half-bridge circuit, so that the DC-DC half-bridge circuit outputs an equivalent voltage source, thereby providing a circulating current and part of the excitation energy to the ring winding structure SRG;

[0015] c) Acquire the actual output voltage of the system, subtract the actual output voltage from the set reference output voltage to obtain the output voltage difference, send the output voltage difference to the output voltage PI controller, and the output voltage PI controller outputs the peak value of the reference line current according to the output voltage difference;

[0016] Collect the three-phase Hall signal of the ring winding structure SRG, send the three-phase Hall signal to the decoder controlled by the six-step commutation method, and the decoder outputs three-phase back electromotive force according to the three-phase Hall signal;

[0017] The three-phase back electromotive force is multiplied by the peak value of the reference line current to obtain the three-phase reference line current, the three-phase reference line current is subtracted from the three-phase actual line current to obtain the three-phase line current difference, the three-phase line current difference is sent to the hysteresis controller, the hysteresis controller outputs a switch control signal according to the three-phase line current difference, and the switch control signal is applied to the six IGBTs of the full-bridge power converter to realize current chopping control;

[0018] When the switch control signal is at a low level, the full-bridge power converter operates in a rectification mode, and the toroidal winding structure SRG outputs a DC voltage through the six diodes of the full-bridge power converter and charges the output capacitor;

[0019] When the switch control signal is at a high level, the full-bridge power converter operates in the inverter mode, the output capacitor is discharged, and part of the excitation energy is provided to the ring winding structure SRG through the six IGBTs of the full-bridge power converter, thereby making the actual output voltage consistent with the reference output voltage.

[0020] The DC-DC half-bridge circuit and the full-bridge power converter are both existing well-known structures.

[0021] Compared with the existing toroidal winding structure SRG system, the toroidal winding structure SRG system output voltage control method described in the present invention improves the existing toroidal winding structure SRG system, and designs a series of feedback loops (speed feedback loop, circulating current feedback loop, line current feedback loop, output voltage feedback loop) for the improved toroidal winding structure SRG system, thereby making the output voltage of the system controllable and with extremely small fluctuations, so that the scope of application of the system is no longer limited.

[0022] In order to verify the beneficial effects of the present invention, simulation experiments are conducted on the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system to obtain the output voltage waveforms and the output voltage and effective value comparison table of the two, as shown in detail below:

[0023] 1. When the reference speed is set to 500r / min, the reference circulating current is set to 2A, and the load resistance is set to 50Ω, the output voltage waveforms of the two are as follows: Figure 4 shown.

[0024] 2. When the reference speed is set to 500r / min, the reference circulating current is set to 2A, and the load resistance is set to 100Ω, the output voltage waveforms of the two are as follows Figure 5 shown.

[0025] 3. When the reference speed is set to 500r / min, the reference circulating current is set to 3A, and the load resistance is set to 50Ω, the output voltage waveforms of the two are as follows: Figure 6 shown.

[0026] 4. When the reference speed is set to 500r / min, the reference circulating current is set to 3A, and the load resistance is set to 100Ω, the output voltage waveforms of the two are as follows Figure 7 shown.

[0027] 5. When the reference speed is set to 1000r / min, the reference circulating current is set to 2A, and the load resistance is set to 50Ω, the output voltage waveforms of the two are as follows: Figure 8 shown.

[0028] 6. When the reference speed is set to 1000r / min, the reference circulating current is set to 2A, and the load resistance is set to 100Ω, the output voltage waveforms of the two are as follows: Fig. 9 shown.

[0029] 7. When the reference speed is set to 1000r / min, the reference circulating current is set to 3A, and the load resistance is set to 50Ω, the output voltage waveforms of the two are as follows: Fig.10 shown.

[0030] 8. When the reference speed is set to 1000r / min, the reference circulating current is set to 3A, and the load resistance is set to 100Ω, the output voltage waveforms of the two are as follows: Fig.11 shown.

[0031] 9. When the load resistance is set to 50Ω, the output voltage and effective value comparison table of the two are as follows:

[0032]

[0033] 10. When the load resistance is set to 100Ω, the output voltage and effective value comparison table of the two are as follows:

[0034]

[0035] It can be seen from the output voltage waveforms and the output voltage and effective value comparison table that the output voltage of the existing ring winding structure SRG system is uncontrollable and fluctuates greatly. The output voltage of the improved ring winding structure SRG system is controllable and fluctuates very little, and the control effect is good.

[0036] The present invention effectively solves the problem that the output voltage of the existing SRG system with a ring winding structure is uncontrollable and has great fluctuations, and is suitable for the SRG system with a ring winding structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is the principle diagram of the existing toroidal winding structure SRG system.

[0038] Figure 2 It is the schematic diagram of the improved toroidal winding structure SRG system.

[0039] Figure 3 It is a control block diagram of the present invention.

[0040] Figure 4 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 1 .

[0041] Figure 5 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 2 .

[0042] Figure 6 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 3 .

[0043] Figure 7 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 4 .

[0044] Figure 8 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 5 .

[0045] Fig. 9 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 6 .

[0046] Fig.10 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 7 .

[0047] Fig.11 The output voltage waveforms of the existing toroidal winding structure SRG system and the improved toroidal winding structure SRG system are shown in Figure 2. Figure 8 .

[0048] In the figure: V1 represents the DC voltage source of the existing ring winding structure SRG system; D1 represents the first diode of the three-phase uncontrolled rectifier circuit; D2 represents the second diode of the three-phase uncontrolled rectifier circuit; D3 represents the third diode of the three-phase uncontrolled rectifier circuit; D4 represents the fourth diode of the three-phase uncontrolled rectifier circuit; D5 represents the fifth diode of the three-phase uncontrolled rectifier circuit; D6 represents the sixth diode of the three-phase uncontrolled rectifier circuit; R1 represents the load resistance of the existing ring winding structure SRG system; V2 represents the improved ring winding structure SRG system The DC voltage source of the system; C1 represents the first capacitor of the DC-DC half-bridge circuit; C2 represents the second capacitor of the DC-DC half-bridge circuit; Q1 represents the first IGBT of the DC-DC half-bridge circuit; Q2 represents the second IGBT of the DC-DC half-bridge circuit; D7 represents the first diode of the DC-DC half-bridge circuit; D8 represents the second diode of the DC-DC half-bridge circuit; T represents the transformer of the DC-DC half-bridge circuit; D9 represents the third diode of the DC-DC half-bridge circuit; D10 represents the fourth diode of the DC-DC half-bridge circuit; I cc Indicates the actual circulating current; i la Indicates the actual line current of phase A; i lb Indicates the actual line current of phase B; i lc Represents the actual line current of phase C; Q3 represents the first IGBT of the full-bridge power converter; Q4 represents the second IGBT of the full-bridge power converter; D11 represents the first diode of the full-bridge power converter; D12 represents the second diode of the full-bridge power converter; Q5 represents the third IGBT of the full-bridge power converter; Q6 represents the fourth IGBT of the full-bridge power converter; D13 represents the third diode of the full-bridge power converter; D14 represents the fourth diode of the full-bridge power converter; Q7 represents the fifth IGBT of the full-bridge power converter; Q8 represents the sixth IGBT of the full-bridge power converter; D15 represents the fifth diode of the full-bridge power converter; D16 represents the sixth diode of the full-bridge power converter; R2 represents the load resistance of the improved toroidal winding structure SRG system; C3 represents the output capacitor. DETAILED DESCRIPTION

[0049] A method for controlling output voltage of a toroidal winding structure SRG system is implemented by the following steps:

[0050] Step 1: Improve the existing toroidal winding structure SRG system, the improved toroidal winding structure SRG system includes a DC voltage source V2, a DC-DC half-bridge circuit, a toroidal winding structure SRG, a full-bridge power converter, a load resistor R2, and an output capacitor C3;

[0051] The two output ends of the DC voltage source V2 are respectively connected to the two input ends of the DC-DC half-bridge circuit; the two output ends of the DC-DC half-bridge circuit are respectively connected to the two ends of the ring winding of the ring winding structure SRG; the three output ends of the ring winding structure SRG are respectively connected to the three AC ends of the full-bridge power converter; the load resistor R2 and the output capacitor C3 are both connected in parallel to the two DC ends of the full-bridge power converter;

[0052] Step 2: During system operation, the system is controlled as follows:

[0053] a) collecting the actual speed of the ring winding structure SRG, subtracting the actual speed from the set reference speed to obtain a speed difference, sending the speed difference to a speed PI controller, and the speed PI controller outputs the input torque of the ring winding structure SRG according to the speed difference;

[0054] b) Collect the three-phase actual phase current and the three-phase actual line current of the ring winding structure SRG, and calculate the actual circulating current of the ring winding structure SRG according to the collected results; the specific calculation formula is as follows:

[0055]

[0056] Where: I cc Indicates the actual circulating current; i pc Indicates the actual phase current of phase C; i la Indicates the actual line current of phase A; i lb Indicates the actual line current of phase B;

[0057] The actual circulating current is subtracted from the set reference circulating current to obtain a circulating current difference, and the circulating current difference is sent to a circulating current PID controller, and the circulating current PID controller outputs a modulation signal according to the circulating current difference;

[0058] A switching control signal is obtained by PWM modulating the modulation signal and the triangular wave, and the switching control signal is applied to two IGBTs of the DC-DC half-bridge circuit, so that the DC-DC half-bridge circuit outputs an equivalent voltage source, thereby providing a circulating current and part of the excitation energy to the toroidal winding structure SRG;

[0059] c) Acquire the actual output voltage of the system, subtract the actual output voltage from the set reference output voltage to obtain the output voltage difference, send the output voltage difference to the output voltage PI controller, and the output voltage PI controller outputs the peak value of the reference line current according to the output voltage difference;

[0060] Collect the three-phase Hall signal of the ring winding structure SRG, send the three-phase Hall signal to the decoder controlled by the six-step commutation method, and the decoder outputs three-phase back electromotive force according to the three-phase Hall signal;

[0061] The three-phase back electromotive force is multiplied by the peak value of the reference line current to obtain the three-phase reference line current, the three-phase reference line current is subtracted from the three-phase actual line current to obtain the three-phase line current difference, the three-phase line current difference is sent to the hysteresis controller, the hysteresis controller outputs a switch control signal according to the three-phase line current difference, and the switch control signal is applied to the six IGBTs of the full-bridge power converter to realize current chopping control;

[0062] When the switch control signal is at a low level, the full-bridge power converter operates in a rectification mode, and the ring winding structure SRG outputs a DC voltage through the six diodes of the full-bridge power converter and charges the output capacitor C3;

[0063] When the switch control signal is at a high level, the full-bridge power converter operates in the inverter mode, the output capacitor C3 is discharged, and part of the excitation energy is provided to the ring winding structure SRG through the six IGBTs of the full-bridge power converter, thereby making the actual output voltage consistent with the reference output voltage.

[0064] During specific implementation, in step 2, the frequency of the triangle wave is 5000 Hz.

[0065] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these implementation modes without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A method for controlling output voltage of a toroidal winding structure SRG system. Features: This method is implemented by the following steps: Step 1: improving the existing toroidal winding structure SRG system, the improved toroidal winding structure SRG system includes a DC voltage source (V2), a DC-DC half-bridge circuit, a toroidal winding structure SRG, a full-bridge power converter, a load resistor (R2), and an output capacitor (C3); The two output ends of the DC voltage source (V2) are respectively connected to the two input ends of the DC-DC half-bridge circuit; the two output ends of the DC-DC half-bridge circuit are respectively connected to the two ends of the ring winding of the ring winding structure SRG; the three output ends of the ring winding structure SRG are respectively connected to the three AC ends of the full-bridge power converter; the load resistor (R2) and the output capacitor (C3) are both connected in parallel to the two DC ends of the full-bridge power converter; Step 2: During system operation, the system is controlled as follows: a) collecting the actual speed of the ring winding structure SRG, subtracting the actual speed from the set reference speed to obtain a speed difference, sending the speed difference to a speed PI controller, and the speed PI controller outputs the input torque of the ring winding structure SRG according to the speed difference; b) Collect the three-phase actual phase current and the three-phase actual line current of the ring winding structure SRG, and calculate the actual circulating current of the ring winding structure SRG according to the collected results; the specific calculation formula is as follows: Where: I cc Indicates the actual circulating current; i pc Indicates the actual phase current of phase C; i la Indicates the actual line current of phase A; i lb Indicates the actual line current of phase B; The actual circulating current is subtracted from the set reference circulating current to obtain a circulating current difference, and the circulating current difference is sent to a circulating current PID controller, and the circulating current PID controller outputs a modulation signal according to the circulating current difference; A switching control signal is obtained by PWM modulating the modulation signal and the triangular wave, and the switching control signal is applied to two IGBTs of the DC-DC half-bridge circuit, so that the DC-DC half-bridge circuit outputs an equivalent voltage source, thereby providing a circulating current and part of the excitation energy to the toroidal winding structure SRG; c) Acquire the actual output voltage of the system, subtract the actual output voltage from the set reference output voltage to obtain the output voltage difference, send the output voltage difference to the output voltage PI controller, and the output voltage PI controller outputs the peak value of the reference line current according to the output voltage difference; Collect the three-phase Hall signal of the ring winding structure SRG, send the three-phase Hall signal to the decoder controlled by the six-step commutation method, and the decoder outputs three-phase back electromotive force according to the three-phase Hall signal; The three-phase back electromotive force is multiplied by the peak value of the reference line current to obtain the three-phase reference line current, the three-phase reference line current is subtracted from the three-phase actual line current to obtain the three-phase line current difference, the three-phase line current difference is sent to the hysteresis controller, the hysteresis controller outputs a switch control signal according to the three-phase line current difference, and the switch control signal is applied to the six IGBTs of the full-bridge power converter to realize current chopping control; When the switch control signal is at a low level, the full-bridge power converter operates in a rectification mode, and the ring winding structure SRG outputs a DC voltage through six diodes of the full-bridge power converter and charges the output capacitor (C3); When the switch control signal is at a high level, the full-bridge power converter operates in the inverter mode, the output capacitor (C3) is discharged, and part of the excitation energy is provided to the ring winding structure SRG through the six IGBTs of the full-bridge power converter, thereby making the actual output voltage consistent with the reference output voltage.

2. The output voltage control method of a toroidal winding structure SRG system according to claim 1, Features: In the step 2, the frequency of the triangle wave is 5000 Hz.

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