阅读说明：本技术 一种共中线拓扑开绕组异步电机驱动控制方法 (common neutral line topology open winding asynchronous motor drive control method ) 是由 杨淑英 胡晓海 符焕 谢震 张兴 于 2019-09-12 设计创作，主要内容包括：本发明公开了一种共中线拓扑开绕组异步电机驱动控制方法,所述共中线拓扑将两个独立直流母线中点通过中线相连形成共中线结构,使得两个逆变器之间存在公共参考点,消除了高频脉动,提升了系统的安全性。同时它还具备共直流母线所不具备的多源混合驱动能力,保留了独立母线配置的灵活性。本发明所述驱动控制方法实现了对共中线开绕组结构中电容C1电压的控制,使其稳定在固定的一个值不发生偏移,从而系统能够稳定运行,提升了系统的驱动性能。(The invention discloses a common neutral line topology open winding asynchronous motor driving control method, wherein the common neutral line topology connects the midpoints of two independent direct current buses through a neutral line to form a common neutral line structure, so that a common reference point exists between two inverters, high-frequency pulsation is eliminated, and the safety of a system is improved.)

The topological structure of the common neutral line topological open winding asynchronous motor related to the driving control method comprises a third direct current source E, a second direct current source E, a 0 th three-phase inverter A, a second three-phase inverter A, a three-phase stator winding D, a neutral line I and 4 filter capacitors, wherein the 4 filter capacitors are respectively marked as a filter capacitor C, a filter capacitor C and a filter capacitor C, 1 end of the filter capacitor C is connected with the positive pole of the 2 nd direct current source E, the end of the filter capacitor C is connected with the negative pole of the third direct current source E, the filter capacitor C is connected with the filter capacitor C in series and then connected with the third phase inverter A in parallel, the common joint point of the filter capacitor C and the filter capacitor C in series is marked as a point a, the end of the filter capacitor C is connected with the positive pole of the second direct current source E, the end of the filter capacitor C is connected with the negative pole of the second direct current source E, the filter capacitor C and the filter capacitor C are connected with the second three-phase inverter A in parallel, the common joint point b of the filter capacitor C and the common joint point b of the three-phase stator winding A;

the drive control method is characterized in that the voltage of the filter capacitor C1 is controlled, and the voltage of the filter capacitor C1 is recorded as a capacitor voltage U₁The method comprises the following specific steps:

step 1, collecting three-phase stator winding current i_a，i_b，i_cCapacitor voltage U₁；

Step 2, the three-phase stator winding current i acquired in the step 1 is processed_a，i_b，i_cα axes are obtained by transforming three-phase stationary coordinates to two-phase stationary coordinates αβ 0Current i_αβ Axis Current i_β0 axis current i₀Then α axis current i_αβ Axis Current i_β0 axis current i₀Converting the two-phase stationary coordinate system into the two-phase synchronous rotating coordinate system dq0 to obtain the d-axis current i_dQ-axis current i_q0 axis current i₀；

The transformation formula for transforming from the three-phase stationary coordinate system to the two-phase stationary coordinate system αβ 0 is:

the transformation formula for transforming from the two-phase stationary coordinate system to the two-phase synchronous rotating coordinate system is as follows:

wherein θ is a given current phase angle;

step 3, collecting the capacitance voltage U₁With a given voltage value

in the formula, k_pProportionality coefficients for closed-loop control of voltage，k_iIs the integral coefficient of voltage closed-loop control, and s is a Laplace operator;

step 4, the 0-axis current reference value obtained in the step 3 is used

wherein k is_p0Proportional coefficient, k, for closed-loop control of 0-axis current_i0Integral coefficient, k, for 0-axis current closed-loop control_pdProportional coefficient, k, for closed-loop control of d-axis current_idIntegral coefficient, k, for closed-loop control of d-axis current_pqProportional coefficient, k, for closed-loop control of q-axis current_iqAn integral coefficient for q-axis current closed-loop control;

step 5, the d-axis voltage U obtained in the step 4 is used_dQ-axis voltage U_qAnd 0 axis voltage U₀A drive signal S1 that drives the th three-phase inverter a1 and a drive signal S2 that drives the second three-phase inverter a2 are generated by PWM wave generation.

Technical Field

The invention belongs to the field of electric drive technology in the power electronic field, and particularly relates to a drive control method of open-winding asynchronous motors with common neutral line topological structures.

Background

Compared with the switch utilization rate of 0.159 of 2L-VSI, the utilization rate of 0.138 of the OWEM only increases the relative cost by 15 percent, but greatly increases the power density (IM73 percent and IPM300 percent) and the torque output capacity of the motor, and related researches show that OWEM fault redundancy cost is the lowest.

series of researches are developed at home and abroad aiming at the drive control method of the open winding motor.

An article entitled "High Performance Power Converter for Combined Batteries-Supercalizer Systems" (High Performance Power Converter Power-capacitor hybrid architecture System, Motor International conference in 2018, ICEM). Aiming at a power supply and capacitor hybrid driving system in an independent direct current bus structure, energy storage units with two different power and energy characteristics, namely a storage battery and a super capacitor, are arranged on the direct current sides of two inverters, so that the optimal mixing of different energy sources is realized. However, high frequency pulsation exists between the buses, which causes a safety problem.

An article entitled "double-inverter SVPWM modulation strategy and zero-sequence voltage suppression method" (the report of Motor engineering in China, 36 th volume, fourth period 1042 and 1049 in 2016). Aiming at the zero-sequence circulating current problem of the common direct current bus, the acting time of the zero vector is redistributed, and zero-sequence circulating current suppression is realized. However, the common bus cannot realize multi-source hybrid drive and cannot meet the hybrid drive requirement of the new energy automobile.

An article entitled "Power Enhancement of Dual Inverter for Open-end Permanent magnet Motor" (Open winding Permanent magnet Motor Power Enhancement, IEEE conference, 2013, APEC). The advantages of the common-neutral open-winding configuration are mentioned, but no study is made on its drive control strategy.

In summary, the following problems still exist in the prior art relating to open-winding motor drive:

1. the research content mainly lies in the drive control of a common direct current bus structure and an independent direct current bus structure, but the common direct current bus structure cannot realize multi-source hybrid drive and cannot meet the requirements of new energy automobiles. High-frequency pulsation exists between two buses of an independent direct-current bus structure, so that the problem of electromagnetic compatibility is caused;

2. the common neutral line structure can realize multi-source hybrid drive, high-frequency pulsation does not exist between buses, the electromagnetic compatibility is good, and research on a drive control method of the common neutral line structure is lacked.

Disclosure of Invention

The invention discloses a drive control method of common neutral line topology open-winding asynchronous motors, which explores and researches the drive control of a common neutral line structure of a new energy automobile, fills the blank of the field, realizes the control of the voltage of a common neutral line structure filter capacitor C1 under the drive control method, and improves the performance of a system.

The invention aims to realize the driving control method of the common neutral line topological open winding asynchronous motor, wherein the topological structure of the common neutral line topological open winding asynchronous motor related to the driving control method comprises a third direct current source E, a second direct current source E, a 0 th three-phase inverter A, a second three-phase inverter A, a three-phase stator winding D, a neutral line I and 4 filter capacitors, wherein the 4 filter capacitors are respectively marked as a filter capacitor C, a filter capacitor C and a filter capacitor C, 1 end of the filter capacitor C is connected with the positive pole of the 2 nd direct current source E, the end of the filter capacitor C is connected with the negative pole of the second direct current source E, the filter capacitor C is connected with the filter capacitor C in series and then connected with the third phase inverter A in parallel, the common connection point of the filter capacitor C and the filter capacitor C in series is marked as a, the positive pole of the second direct current source E of the filter capacitor C is connected with the negative pole of the second direct current source E, the filter capacitor C is connected with the common connection point of the filter capacitor C in series, the common connection point of the filter capacitor C is marked as a point a, the connection point of the third direct current source E is connected with the third phase inverter A, the neutral line B is connected with the three-phase stator winding A, and the three-phase stator winding A;

the drive control method is to control the voltage of the filter capacitor C1, and the voltage of the filter capacitor C1 is recorded as the capacitor voltage U₁The method comprises the following specific steps:

step 1, collecting three-phase stator winding i_a，i_b，i_cCapacitor voltage U₁；

Step 2, the three-phase stator winding current i acquired in the step 1 is processed_a，i_b，i_cConversion to a two-phase stationary coordinate αβ 0 by a three-phase stationary coordinate yields a α -axis current i_αβ Axis Current i_β0 axis current i₀Then α axis current i_αβ Axis Current i_β0 axis current i₀Converting the two-phase stationary coordinate system into the two-phase synchronous rotating coordinate system dq0 to obtain the d-axis current i_dQ-axis current i_q0 axis current i₀；

The transformation formula for transforming from the three-phase stationary coordinate system to the two-phase stationary coordinate system αβ 0 is:

the transformation formula for transforming from the two-phase stationary coordinate system to the two-phase synchronous rotating coordinate system is as follows:

wherein θ is a given current phase angle;

step 3, collecting the capacitance voltage U₁With a given voltage valueMaking a difference to obtain a voltage difference U_erI.e. by

Then the voltage difference U is measured_erObtaining a 0-axis current reference value through a PI regulator 1

The expression is as follows:

in the formula, k_pProportionality coefficient, k, for closed-loop control of voltage_iIs the integral coefficient of voltage closed-loop control, and s is a Laplace operator;

step 4, the 0-axis current reference value obtained in the step 3 is used

And the 0-axis current i obtained in the step 2₀Obtaining a 0-axis current difference i by difference_0erI.e. by

Then 0 axis current difference i_0erObtaining a 0-axis voltage U through a PI regulator 2₀(ii) a D-axis current i obtained in step 2_dWith a given d-axis current value

Obtaining d-axis current difference i by difference_derI.e. by

Then the d-axis current difference i_derObtaining d-axis voltage U through PI regulator 3_d(ii) a The q-axis current i obtained in the step 2_qWith a given q-axis current valueObtaining a q-axis current difference i by difference_qerI.e. byThen the q-axis current difference i_qerThe q-axis voltage U is obtained through a PI regulator 4_q(ii) a The expressions are respectively:

wherein k is_p0Proportional coefficient, k, for closed-loop control of 0-axis current_i0Integral coefficient, k, for 0-axis current closed-loop control_pdProportional coefficient, k, for closed-loop control of d-axis current_idIntegral coefficient, k, for closed-loop control of d-axis current_pqProportional coefficient, k, for closed-loop control of q-axis current_iqAn integral coefficient for q-axis current closed-loop control;

step 5, the d-axis voltage U obtained in the step 4 is used_dQ-axis voltage U_qAnd 0 axis voltage U₀A drive signal S1 that drives the th three-phase inverter a1 and a drive signal S2 that drives the second three-phase inverter a2 are generated by PWM wave generation.

Compared with the existing common neutral line topology open winding asynchronous motor driving technology, the invention has the beneficial effects that:

1. under the drive control method, the control of the voltage of the common neutral open winding structure filter capacitor C1 is realized, so that the common neutral open winding structure filter capacitor C1 is stabilized at a fixed value of and does not deviate;

2. the control of the voltage of the common neutral open winding structure filter capacitor C1 enables the system to operate stably, improves the safety of the system, and improves the driving performance of the motor.

Drawings

Fig. 1 is a topological structure of a common neutral line topological open winding asynchronous motor.

FIG. 2 is a schematic diagram of two coordinate transformations in the present invention.

Fig. 3 is a control block diagram of the voltage of the common neutral line topology open winding filter capacitor C1 according to the present invention.

Fig. 4 shows the simulation result of the voltage control of the common neutral line topology open winding filter capacitor C1 according to the present invention.

Detailed Description

Referring to fig. 1, the topology structure of the common neutral line topology open-winding asynchronous motor according to the present invention includes th dc source E1, second dc source E2, th three-phase inverter a1, second three-phase inverter a2, three-phase stator winding D, neutral line I and 4 filter capacitors.

The method comprises the steps of respectively marking 4 filter capacitors as a filter capacitor C1, a filter capacitor C1 and a filter capacitor C4, connecting a1 of the filter capacitor C1 with the positive electrode of a 1-th direct current source E1, connecting a1 of the filter capacitor C1 with the negative electrode of the 1-th direct current source E1, connecting the filter capacitor C1 and the filter capacitor C1 in series and then connecting the filter capacitor C1 with the three-phase inverter A1 in parallel, marking a common junction of the filter capacitor C1 and the filter capacitor C1 in series as a point a, connecting the 1 of the filter capacitor C1 with the positive electrode of the second direct current source E1, connecting the 1 of the filter capacitor C1 with the negative electrode of the second direct current source E1, connecting the filter capacitor C1 with the common junction of the filter capacitor C1 and the filter capacitor C1 in series as a point b, and connecting a neutral line I connecting point b, connecting the three-phase inverter winding 1A with the three-phase stator winding 1D, and connecting the three-phase stator 1 with the three-phase inverter.

In this embodiment, the dc-side voltage of the th dc source E1 is 400V, the capacitance of the filter capacitor C1 is 2048 μ F, the capacitance of the filter capacitor C2 is 2048 μ F, the dc-side voltage of the second dc source E2 is 400V, the capacitance of the filter capacitor C1 is 2048 μ F, and the capacitance of the filter capacitor C2 is 2048 μ F.

Referring to fig. 2 and 3, the driving control method is to control the voltage of the filter capacitor C1, and the voltage of the filter capacitor C1 is recorded as the capacitor voltage U₁The method comprises the following specific steps:

step 1, collecting three-phase stator winding i_a，i_b，i_cCapacitor voltage U₁。

Step 2, the three-phase stator winding current i acquired in the step 1 is processed_a，i_b，i_cConversion to a two-phase stationary coordinate αβ 0 by a three-phase stationary coordinate yields a α -axis current i_αβ Axis Current i_β0 axis current i₀Then α axis current i_αβ Axis Current i_β0 axis current i₀Converting the two-phase stationary coordinate system into the two-phase synchronous rotating coordinate system dq0 to obtain the d-axis current i_dQ-axis current i_q0 axis current i₀。

The transformation formula for transforming from the three-phase stationary coordinate system to the two-phase stationary coordinate system αβ 0 is:

the transformation formula for transforming from the two-phase stationary coordinate system to the two-phase synchronous rotating coordinate system is as follows:

where θ is a given current phase angle.

Step 3, collecting the capacitance voltage U₁With a given voltage value

Making a difference to obtain a voltage difference U_erI.e. by

Then the voltage difference U is measured_erObtaining a 0-axis current reference value through a PI regulator 1

The expression is as follows:

in the formula, k_pProportionality coefficient, k, for closed-loop control of voltage_iAnd s is a Laplace operator, which is an integral coefficient of voltage closed-loop control. In this example

At 200V, take k_p＝10，k_i＝0。

Step 4, the 0-axis current reference value obtained in the step 3 is used

And the 0-axis current i obtained in the step 2₀Obtaining a 0-axis current difference i by difference_0erI.e. by

Then 0 axis current difference i_0erObtaining a 0-axis voltage U through a PI regulator 2₀(ii) a D-axis current i obtained in step 2_dWith a given d-axis current value

Obtaining d-axis current difference i by difference_derI.e. by

Then the d-axis current difference i_derObtaining d-axis voltage U through PI regulator 3_d(ii) a The q-axis current i obtained in the step 2_qWith a given q-axis current valueObtaining a q-axis current difference i by difference_qerI.e. by

Then the q-axis current difference i_qerThe q-axis voltage U is obtained through a PI regulator 4_q(ii) a The expressions are respectively:

wherein k is_p0Proportional coefficient, k, for closed-loop control of 0-axis current_i0Integral coefficient, k, for 0-axis current closed-loop control_pdProportional coefficient, k, for closed-loop control of d-axis current_idIntegral coefficient, k, for closed-loop control of d-axis current_pqProportional coefficient, k, for closed-loop control of q-axis current_iqIs an integral coefficient of the q-axis current closed-loop control.

In this examplek_p0＝100，k_i0＝0，k_pd＝150，k_id＝1000，k_pq＝150，k_iq＝1000。

Step 5, the d-axis voltage U obtained in the step 4 is used_dQ-axis voltage U_qAnd 0 axis voltage U₀A drive signal S1 that drives the th three-phase inverter a1 and a drive signal S2 that drives the second three-phase inverter a2 are generated by PWM wave generation.

FIG. 4 is a simulation result of voltage control of the common neutral line topology open winding filter capacitor C1. the DC side voltages of the DC source E1 and the second DC source E2 are both 400V, and the filter capacitor C1 gives a voltage value

Is 200V. From the results of the simulation of figure 4,voltage value U of filter capacitor C1₁Stabilized at a given voltage value

And deviation does not occur, which shows that the driving control method can effectively stabilize the voltage of the capacitor C1 and improve the driving performance of the system.