A complex vector current control method for a dual-winding induction AC / DC generator system

Abstract

The present application discloses a complex vector current control method for a dual-winding induction AC / DC generator system, which relates to the field of dual-winding induction motors. The method introduces a complex vector current controller into the current control of the dual-winding induction generator, achieves accurate tracking of the phase current by controlling the phase voltage of the winding, and also takes into account the cross-coupling terms in the antagonistic power winding. By designing the complex vector current and utilizing the decoupling terms to perform decoupling control, the interference between the power winding and the control winding is reduced, ensuring that the dual-winding motor system can stably perform current control at high speeds, thereby achieving better decoupling control in the high-speed AC / DC power generation of the dual-winding induction generator, improving the current decoupling effect at high speeds, and enhancing system performance, thereby effectively improving the system performance and parameter robustness of the dual-winding induction motor during high-speed AC / DC power generation control.

Description

Technical Field

[0001] The present application relates to the field of dual-winding induction motors, and in particular to a complex vector current control method for a dual-winding induction AC / DC generator system. Background Art

[0002] Multi-electric engine technology uses a new electromechanical structure to optimize the conversion performance of secondary energy in secondary energy generation systems. One of the key technologies is to embed the generator and starter / generator into the engine to form a mechatronic structure. Therefore, in the context of multi-electric engines, the design and optimization of aircraft generators have an important research position. With the development of electric propulsion systems in aerospace, aircraft are increasingly demanding high-performance motors. The propulsion systems of electric aircraft, drones, and other space equipment are increasingly relying on electric drive. The control flexibility and fault redundancy of traditional single-winding motors cannot meet the requirements of these high-end applications. Therefore, the development of dual-winding motors has become a natural choice to meet these high power density, high reliability, and high fault tolerance requirements.

[0003] Compared to other motors, the development of dual-winding induction motors in the aerospace field has unique technical backgrounds and requirements. Their development is primarily driven by the need to meet the high-performance, multifunctional, highly reliable, and fault-tolerant motor drive requirements of aircraft systems. However, the magnetic fields generated by the currents in the two stator windings of a dual-winding induction motor interact with each other, and the currents in the control-side winding and the power-side winding influence each other. This leads to the risk of instability in traditional PI current control under high-speed operating conditions of dual-winding induction motor power generation systems, resulting in low system control stability. Summary of the Invention

[0004] In response to the above-mentioned problems and technical requirements, this application proposes a complex vector current control method for a dual-winding induction AC / DC generator system. The technical solution of this application is as follows:

[0005] A complex vector current control method for a dual-winding induction AC / DC generator system, the complex vector current control method comprising:

[0006] The expected value of DC voltage U dcref The DC voltage amplitude U across the DC load connected to the control winding of a dual-winding induction motor dc The error is input into the PI controller to obtain the q-axis reference current i of the control winding cqref ; Set the AC voltage expected value U pacref The effective value of the AC voltage U across the AC load connected to the power winding of a double-winding induction motor pac After making the difference, input it into the PI controller to get the d-axis reference current i of the control winding cdref ;

[0007] according to Design the d-axis current loop to obtain the d-axis given voltage of the control winding, according to Design the q-axis current loop to obtain the q-axis given voltage of the control winding; where i cd is the d-axis current of the control winding, i cq is the q-axis current of the control winding, K p is the proportional term coefficient, K i is the integral term coefficient, K c is the decoupling term coefficient and is related to the real-time electrical angular velocity ω of the dual-winding induction motor e Related, s is the Laplace transform variable in the complex frequency domain;

[0008] A power converter connected to a control winding of a dual-winding induction motor is controlled using vector modulation based on a d-axis given voltage and a q-axis given voltage of the control winding.

[0009] Its further technical solution is that the proportional term coefficient K p , integral term coefficient K i , decoupling coefficient K c The calculation formula is:

[0010]

[0011] Where ω is the system design bandwidth, R c ′ is the equivalent resistance of the control winding and R c is the resistance of the control winding, R r is the equivalent rotor resistance, ω e is the real-time electrical angular velocity of the dual-winding induction motor, L c is the inductance of the control winding, L r is the rotor equivalent inductance, L m It is the main inductance of the double-winding induction motor.

[0012] A further technical solution is that the complex vector current control method further includes:

[0013] The flux amplitude ψ is obtained based on the phase current of the control winding and the phase current of the power winding of the dual-winding induction motor. r ;

[0014] According to the magnetic flux amplitude ψ r Disturbance compensation items are added to the d-axis current loop and the q-axis current loop respectively to perform disturbance compensation.

[0015] Its further technical solution is to use the magnetic flux amplitude ψ r The disturbance compensation for the d-axis current loop includes:

[0016] For the d-axis current loop Add the d-axis disturbance compensation term to the output of

[0017] Among them, L r is the rotor equivalent inductance, T r is the time constant of the two-winding induction motor and T r =L r / R r ′, R r is the equivalent rotor resistance, L m It is the main inductance of the double-winding induction motor.

[0018] Its further technical solution is to use the magnetic flux amplitude ψ r The disturbance compensation for the q-axis current loop includes:

[0019] For the q-axis current loop Add q-axis disturbance compensation term to the output Among them, ω r is the rotor flux angular velocity and ω r =(1-ζ)·ω e , ζ is the slip rate.

[0020] A further technical solution is to observe the magnetic flux amplitude in:

[0021]

[0022] Among them, T r is the time constant of the two-winding induction motor and T r =L r / R r ′, R r is the equivalent rotor resistance, L r is the rotor equivalent inductance, L m is the main inductance of the double-winding induction motor; p is the differential operator; ω r is the rotor flux angular velocity and ω r =(1-ζ)·ω e ,ζ is the slip rate; i cα and i cβ They are the α-axis current and β-axis current obtained by converting the phase current of the control winding, i pα and i pβ They are the α-axis current and β-axis current obtained by converting the phase current of the power winding.

[0023] A further technical solution is that the complex vector current control method further includes:

[0024] In the d-axis current loop, The output of is passed through the delay compensator and then the d-axis disturbance compensation term is added to obtain the d-axis given voltage;

[0025] In the q-axis current loop, The output of is passed through the delay compensator and then the q-axis disturbance compensation term is added to obtain the q-axis given voltage;

[0026] Among them, the transfer functions of the delay compensators in the d-axis current loop and the q-axis current loop are Phase advance compensation is performed, K is the gain of the delay compensator, T1 and T2 are the zero and pole time constants of the phase advance compensation respectively, and T1>T2.

[0027] Its further technical solution is:

[0028] Where ω is the system design bandwidth, φ m is the desired phase boost angle.

[0029] A further technical solution is that the complex vector current control method further includes:

[0030] In the d-axis current loop, A low-pass filter is also provided between the output and the delay compensator;

[0031] In the q-axis current loop, A low-pass filter is also provided between the output and the delay compensator;

[0032] Among them, the transfer functions of the low-pass filters in the d-axis current loop and the q-axis current loop are T is the cutoff frequency of the low-pass filter.

[0033] A further technical solution is that the cut-off frequency T of the low-pass filter is set to the switching frequency of the switch tube.

[0034] The beneficial technical effects of this application are:

[0035] This application discloses a complex vector current control method for a dual-winding induction AC / DC generator system. This method introduces a complex vector current controller into the current control of the dual-winding induction generator. The method achieves precise tracking of the phase current of the control winding by controlling the phase voltage of the winding. It also takes into account the cross-coupling terms in the counteracting power winding. By designing a complex vector current decoupling control, the interference between the power winding and the control winding is reduced, ensuring that the dual-winding motor system can stably control the current at high speeds. This allows for better decoupling control in the high-speed AC / DC power generation of the dual-winding induction generator, and higher control accuracy in the dynamic performance of the motor. This solution improves the current decoupling effect at high speeds and enhances system performance. It also maintains good control effects when the parameters of the dual-winding induction generator change, effectively improving the system performance and parameter robustness of the dual-winding induction motor during high-speed AC / DC power generation control.

[0036] This method further improves the current loop control accuracy and system oscillation issues of dual-winding induction motors at high speeds by designing a flux observer to compensate for the current loop. Secondly, phase compensation compensates for phase lag and delay in the system. A filter design weakens oscillations caused by high-frequency noise and reduces the control system's gain in the high-frequency range, improving the system's frequency response. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a system control block diagram of a complex vector current control method for a dual-winding induction AC / DC generator system according to an embodiment of the present application.

[0038] Figure 2 This is the traditional PI current control block diagram.

[0039] Figure 3 This is a scalar structure diagram of a dual-winding induction motor considering the time delay in this application.

[0040] Figure 4 This is a control block diagram of a complex vector current controller in one embodiment of the present application. DETAILED DESCRIPTION

[0041] The specific implementation of this application will be further described below with reference to the accompanying drawings.

[0042] This application discloses a complex vector current control method for a dual-winding induction AC / DC generator system. Figure 1As shown in the system control block diagram, in the dual-winding induction AC / DC generator system, the dual-winding induction motor includes a control winding and a power winding. The control winding of the dual-winding induction motor is connected to the power converter, and the starting power supply is connected to the DC bus of the power converter. In addition, the control winding is also connected to the DC load for DC power supply. The power winding of the dual-winding induction motor is connected to the AC load for AC power supply. Figure 1 Taking a five-phase to three-phase dual-winding induction motor as an example, the control winding includes five-phase windings A, B, C, D, and E, and the power winding includes three-phase windings F, G, and H.

[0043] During the operation of the dual-winding induction AC / DC generator, the phase currents of each phase of the control winding are collected, such as Figure 1 in,i a 、i b 、i c 、i d 、i e The phase currents of the five-phase control windings A, B, C, D, and E are obtained respectively. Then, the α-axis current i of the control winding in the αβ coordinate system can be obtained by performing Clarke transformation on the phase current of each phase control winding. cα and β-axis current i cβ , further park transformation can be performed to obtain the d-axis current i of the control winding in the dq coordinate system cd and q-axis current i cq The traditional PI current control method is to obtain and convert the d-axis current i cd and q-axis current i cq Afterwards, Figure 2 As shown, the expected value of the d-axis current i cdcmd and d-axis current i cd After the difference is made, it passes through the PI controller to output the d-axis given voltage u cd1 and u cd3 , where u cd1 is the given standard voltage component in the d-axis direction, u cd3 is the third harmonic given voltage component in the d-axis direction. Similarly, the expected value of the q-axis current i cqcmd and q-axis current i cq After the difference is made, it passes through the PI controller to output the q-axis given voltage u cq1 and u cq3 , where u cq1 is the given standard voltage component in the q-axis direction, u cq3 The 3rd harmonic given voltage component in the q-axis direction is then used to control the power converter connected to the control winding of the dual-winding induction AC / DC generator using vector modulation based on the d-axis given voltage and the q-axis given voltage.

[0044] For a dual-winding induction motor, the voltage equation in the dq coordinate system is:

[0045]

[0046] Among them, R c is the control winding resistance, R p is the power winding resistance, R r is the equivalent rotor resistance. cd , ψ cq , ψ pd , ψ pq , ψ rd , ψ rq are all current flux components and:

[0047]

[0048] Among them, u cd and u cq is the phase voltage of the control winding in the dq coordinate system, i cd and i cq is the phase current of the control winding in the dq coordinate system. pd and u pq is the phase voltage of the power winding in the dq coordinate system, i pd and i pq is the phase current of the power winding in the dq coordinate system, i rd and i rq is the current of the rotor equivalent circuit in the dq coordinate system. e is the real-time electrical angular velocity, ω s is the slip frequency. L c is the inductance of the control winding, L p is the inductance of the power winding, L r is the rotor equivalent inductance, L m is the main inductance of the two-winding induction motor. t represents time.

[0049] It can be seen from the above equations (1) and (2) that there is a magnetic field coupling effect between the control winding and the power winding of the dual-winding induction motor. This magnetic field coupling effect gradually intensifies with the increase of the speed, causing the phase current of the control winding and the phase current of the power winding to affect each other and introduce additional cross-coupling terms. It is precisely because of these cross-coupling terms that the use of the following formula will be adopted: Figure 2 The traditional PI current control shown is prone to instability under high speed conditions.

[0050] For this purpose, this application introduces a complex vector current control method. In the dual-winding induction motor power generation vector control, the rotor flux orientation can realize the decoupling control of the current flux component and the torque component. The d-axis of the two-phase rotating coordinate system is fixed on the rotor flux vector. At this time, the flux amplitude ψ r =ψrd And ψ rq =0, from this we can know that:

[0051]

[0052] Substituting equation (3) into equations (1) and (2) for calculation, we can obtain the dq axis phase voltage u of the control winding: cd and u cq The voltage amplitude calculation formula between:

[0053]

[0054] in, Equivalent resistance of control winding T r is the time constant of the two-winding induction motor and T r =L r / R r ′, p is the differential operator. Based on formula (4), the scalar structure diagram of the dual-winding induction motor can be obtained as follows: Figure 3 As shown, It represents the relationship between the given voltage of the control winding and the given current of the power winding. Specifically, Z load represents the power winding load impedance of the double-winding induction motor, S(Φ) represents the magnetic saturation factor of the double-winding induction motor, k w represents the pole arc coefficient, and N2 / N1 is the turns ratio of the stator power winding to the control winding. In fact, there is a calculation delay τ in the above process. d , so the final output is taking into account the calculation delay τ d The phase current of the control winding in the dq coordinate system after and And the phase current of the power winding in the dq coordinate system and

[0055] Based on formula (4), the voltage calculation function of the complex vector current controller suitable for the dual-winding induction AC / DC generator system can be established as follows:

[0056]

[0057] The first part of formula (5) represents the resistance and inductance coupling terms between the phase voltage and phase current of the control winding, and the third part represents the disturbance term of the power winding current. These two parts are the most important considerations when designing a complex vector current controller. The main design goal of the first part of formula (5) in the complex vector current controller is to accurately track the phase current of the control winding by controlling the phase voltage of the control winding. The main design goal of the third part of formula (5) in the complex vector current controller is to counteract the cross-coupling term in the power winding. Based on this consideration, the control block diagram of the complex vector current controller of this application is as follows: Figure 4 As shown. Using the complex vector current controller of the present application, during the operation of the dual-winding induction AC / DC generator system, in addition to collecting the phase current of the control winding, the DC voltage amplitude U across the DC load connected to the control winding of the dual-winding induction AC / DC generator is also obtained. dc And the AC voltage RMS U across the AC load connected to the power winding pac .

[0058] The expected value of DC voltage U dcref The DC voltage amplitude U across the DC load dc The error is input into the PI controller to obtain the q-axis reference current i of the control winding cqref . And the AC voltage expected value U pacref The AC voltage RMS value U across the AC load pac After making the difference, input it into the PI controller to obtain the d-axis reference current i of the control winding cdref .

[0059] Then the d-axis reference current i cdref , q-axis reference current i cqref , d-axis current i cd and q-axis current i cq Input the complex vector current controller designed in this application to obtain the d-axis given voltage u cdref and q-axis given voltage u cqref In the designed complex vector current controller:

[0060] according to Design the d-axis current loop to obtain the d-axis given voltage of the control winding. Design the q-axis current loop to obtain the q-axis given voltage of the control winding. p is the proportional term coefficient, K i is the integral term coefficient, K c is the decoupling term coefficient and is related to the real-time electrical angular velocity ω of the dual-winding induction motor e Related, s is the Laplace transform variable in the complex frequency domain.

[0061] Proportional term coefficient K p, integral term coefficient K i , decoupling coefficient K c The motor parameters of the dual-winding induction motor are tuned and are:

[0062]

[0063] Where ω is the system design bandwidth, R c ' is the equivalent resistance of the control winding and the calculation formula is as recorded above, L c is the inductance of the control winding, L r is the rotor equivalent inductance, L m is the main inductance of the double-winding induction motor. e It is the real-time electrical angular velocity of the dual-winding induction motor, which can be obtained by collecting the speed n of the dual-winding induction motor and then using Calculated, where p0 is the number of generator pole pairs.

[0064] The above method can be used to design complex vector current decoupling to reduce the interference between the power winding and the control winding, thereby ensuring that the dual-winding induction AC / DC generator system can stably control the current at high speed and increase the robustness of the system.

[0065] On this basis, it can be seen from formula (5) that the calculation formula of the phase voltage of the control winding also includes the second part, which is the flux cross-coupling term. In one embodiment, in order to further improve the current loop control accuracy reduction and system oscillation problem of the dual-winding induction motor in high-speed situations, the constant rotor flux disturbance term of the dual-winding induction motor is also considered when designing the complex vector current controller to perform feedforward compensation. Therefore, in another embodiment, as Figure 1 As shown in Figure 2, during the operation of the dual-winding induction motor, the phase current of the power winding is also collected, such as Figure 1 i in f 、i g 、i h They are the phase currents of the three-phase power windings F, G, and H respectively. Similarly, by performing Clarke transformation on the phase currents of each phase power winding, the α-axis current i of the power winding in the αβ coordinate system can be obtained. pα and β-axis current i pβ .

[0066] Control winding α-axis current i cα and β-axis current i cβ And the α-axis current i of the power winding pα and β-axis current i pβ The flux observer is then used to obtain the flux amplitude ψ according to the phase current of the control winding and the phase current of the power winding of the dual-winding induction motor. r. Magnetic flux amplitude ψ r The observed value of is obtained by taking the root mean square of the magnetic flux on the α-axis and the β-axis:

[0067]

[0068] The magnetic flux on the α-axis and β-axis is obtained by the following formula:

[0069]

[0070] In the above formula, ω r is the rotor flux angular velocity and ω r =(1-ζ)·ω e , ζ is the slip rate.

[0071] The observed magnetic flux amplitude ψ r Then, according to the magnetic flux amplitude ψ r Disturbance compensation items are added to the d-axis current loop and the q-axis current loop respectively to perform disturbance compensation.

[0072] For the d-axis current loop, the d-axis disturbance compensation term is added to After the output of , the added d-axis disturbance compensation term is

[0073] For the q-axis current loop, the q-axis disturbance compensation term is added to After the output of , the added q-axis disturbance compensation term is

[0074] Furthermore, considering that the calculation delay of the dual-winding induction motor is more significant than that of the ordinary asynchronous motor, in another embodiment, a delay compensator is provided in the d-axis current loop and the q-axis current loop respectively. Figure 4 :

[0075] In the d-axis current loop, The output of is passed through the delay compensator and then the d-axis disturbance compensation term is added to obtain the d-axis given voltage.

[0076] In the q-axis current loop, The output of is passed through the delay compensator and then the q-axis disturbance compensation term is added to obtain the q-axis given voltage.

[0077] The delay compensator is used to compensate for the system phase lag caused by processor calculation, sampling processing, and PWM modulation. Phase advance compensation is adopted. The transfer functions of the delay compensators in the d-axis current loop and the q-axis current loop are:

[0078]

[0079] Where K is the gain of the delay compensator, which is freely selected based on the system default gain. T1 and T2 are the zero and pole time constants of the phase lead compensation, respectively, and T1>T2. In one embodiment, the selection configuration of T1 and T2 is adjusted by the following formula:

[0080]

[0081] Where ω is the system design bandwidth, φ m is the required phase boost angle, which can be set according to the actual system conditions. m Compensate for 10 to 30 degrees.

[0082] Furthermore, considering that the system interference noise of the dual-winding induction motor is more significant than that of the ordinary asynchronous motor, in another embodiment, low-pass filters are respectively set in the d-axis current loop and the q-axis current loop. Figure 4 :

[0083] In the d-axis current loop, A low-pass filter is also set between the output and the delay compensator.

[0084] In the q-axis current loop, A low-pass filter is also set between the output and the delay compensator.

[0085] The low-pass filter is used to filter the system interference noise. The transfer functions of the low-pass filters in the d-axis current loop and the q-axis current loop are:

[0086]

[0087] Wherein, T is the cutoff frequency of the low-pass filter. In one embodiment, the cutoff frequency T of the low-pass filter is set to the switching frequency of the switch tube to filter out the high-frequency noise of the current loop in the dual-winding induction motor.

[0088] In summary, in the d-axis current loop, The output of is first filtered by a low-pass filter to remove noise, then passed through a delay compensator to perform phase advance compensation, and finally the d-axis disturbance compensation term is superimposed. The final output d-axis given voltage includes u cd1 and u cd3 In the q-axis current loop, The output of is first filtered by a low-pass filter to remove noise, then passed through a delay compensator to perform phase advance compensation, and finally the q-axis disturbance compensation term is superimposed. The final output q axis given voltage includes u cq1 and u cq3 .

Claims

1. A complex vector current control method for a dual-winding induction AC / DC generator system, characterized in that: The complex vector current control method includes: The expected value of DC voltage U dcref The DC voltage amplitude U across the DC load connected to the control winding of a dual-winding induction motor dc The error is input into the PI controller to obtain the q-axis reference current i of the control winding cqref ; Set the AC voltage expected value U pacref The effective value of the AC voltage U across the AC load connected to the power winding of a double-winding induction motor pac After making the difference, input it into the PI controller to get the d-axis reference current i of the control winding cdref ; according to Design the d-axis current loop to obtain the d-axis given voltage of the control winding, according to Design the q-axis current loop to obtain the q-axis given voltage of the control winding; where i cd is the d-axis current of the control winding, i cq is the q-axis current of the control winding, K p is the proportional term coefficient, K i is the integral term coefficient, K c is the decoupling term coefficient and is related to the real-time electrical angular velocity ω of the dual-winding induction motor e Related, s is the Laplace transform variable in the complex frequency domain; A power converter connected to a control winding of a dual-winding induction motor is controlled using vector modulation based on a d-axis given voltage and a q-axis given voltage of the control winding.

2. The complex vector current control method according to claim 1, characterized in that: Proportional term coefficient K p , integral term coefficient K i , decoupling coefficient K c The calculation formula is: Where ω is the system design bandwidth, R c ′ is the equivalent resistance of the control winding and R c is the resistance of the control winding, R r is the equivalent rotor resistance, ω e is the real-time electrical angular velocity of the dual-winding induction motor, L c is the inductance of the control winding, L r is the rotor equivalent inductance, L m It is the main inductance of the double-winding induction motor.

3. The complex vector current control method according to claim 1, characterized in that: The complex vector current control method further includes: The flux amplitude ψ is obtained based on the phase current of the control winding and the phase current of the power winding of the dual-winding induction motor. r ; According to the magnetic flux amplitude ψ r Disturbance compensation items are added to the d-axis current loop and the q-axis current loop respectively to perform disturbance compensation.

4. The complex vector current control method according to claim 3, characterized in that: According to the magnetic flux amplitude ψ r The disturbance compensation for the d-axis current loop includes: For the d-axis current loop Add the d-axis disturbance compensation term to the output of Among them, L r is the rotor equivalent inductance, T r is the time constant of the two-winding induction motor and T r =L r / R r ′, R r is the equivalent rotor resistance, L m It is the main inductance of the double-winding induction motor.

5. The complex vector current control method according to claim 3, characterized in that: According to the magnetic flux amplitude ψ r The disturbance compensation for the q-axis current loop includes: For the q-axis current loop Add q-axis disturbance compensation term to the output Among them, ω r is the rotor flux angular velocity and ω r =(1-ζ)·ω e , ζ is the slip rate.

6. The complex vector current control method according to claim 3, characterized in that: Observed magnetic flux amplitude in: Among them, T r is the time constant of the two-winding induction motor and T r =L r / R′ r , R r is the equivalent rotor resistance, L r is the rotor equivalent inductance, L m is the main inductance of the double-winding induction motor; p is the differential operator; ω r is the rotor flux angular velocity and ω r =(1-ζ)·ω e ,ζ is the slip rate; i cα and i cβ They are the α-axis current and β-axis current obtained by converting the phase current of the control winding, i pα and i pβ They are the α-axis current and β-axis current obtained by converting the phase current of the power winding.

7. The complex vector current control method according to claim 3, characterized in that: The complex vector current control method further includes: In the d-axis current loop, The output of is passed through the delay compensator and then the d-axis disturbance compensation term is added to obtain the d-axis given voltage; In the q-axis current loop, The output of is passed through the delay compensator and then the q-axis disturbance compensation term is added to obtain the q-axis given voltage; Among them, the transfer functions of the delay compensators in the d-axis current loop and the q-axis current loop are Phase advance compensation is performed, K is the gain of the delay compensator, T1 and T2 are the zero and pole time constants of the phase advance compensation respectively, and T1>T2.

8. The complex vector current control method according to claim 7, characterized in that: Where ω is the system design bandwidth, φ m is the desired phase boost angle.

9. The complex vector current control method according to claim 7, characterized in that: The complex vector current control method further includes: In the d-axis current loop, A low-pass filter is also provided between the output and the delay compensator; In the q-axis current loop, A low-pass filter is also provided between the output and the delay compensator; Among them, the transfer functions of the low-pass filters in the d-axis current loop and the q-axis current loop are T is the cutoff frequency of the low-pass filter.

10. The complex vector current control method according to claim 9, characterized in that: The cutoff frequency T of the low-pass filter is set to the switching frequency of the switch tube.

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