Concentric cage secondary linear doubly-fed motor steady-state equivalent model construction method and application

Abstract

The invention discloses a steady-state equivalent model construction method and application of a concentric cage secondary linear doubly-fed motor, and belongs to the technical field of motor design. The method comprises the following steps: firstly, constructing a relational expression of a voltage vector, a current vector and an impedance matrix of a primary winding of any phase of the concentric cage secondary linear doubly-fed motor under the condition of neglecting an edge effect, and then correcting by adopting an equivalent impedance matrix representing power consumed by a static edge effect and a dynamic edge effect; and obtaining a steady-state equivalent model of the concentric cage secondary linear doubly-fed motor. In the process, structural information of the concentric cage secondary linear doubly-fed motor is fully utilized, actual concentric cage parameters are adopted to construct the dynamic end effect equivalent impedance matrix, and the steady-state equivalent model of the motor can be constructed more accurately. In addition, the established steady-state equivalent model can represent the direct relation between motor structure parameters and concentric cage electromagnetic parameters, and design and analysis of the motor can be guided more conveniently.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor design, and more specifically, relates to a method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor and its application. Background Art

[0002] Compared with the rotary traction system of urban rail transit, the linear traction system of urban rail transit has the advantages of strong climbing ability, large acceleration, small turning radius, and small shield area. Among them, the concentric cage secondary linear doubly fed machine (NLS-LDFM) has attracted extensive attention due to its adjustable power factor, flexible operation mode, and low operation and maintenance cost. In order to realize the design and optimization of NLS-LDFM, a steady-state equivalent model is often constructed for it. Therefore, it is of great significance to study the construction method of the steady-state equivalent model of NLS-LDFM.

[0003] The primary core of NLS-LDFM is disconnected, and there are end effects, mainly including static end effects and dynamic end effects. The existence of end effects brings great difficulties to the construction of the steady-state equivalent model of NLS-LDFM.

[0004] In the prior art, the following method is usually used to construct the steady-state equivalent model of NLS-LDFM, which equates the concentric cage to the phase winding, adopts the equivalent circuit of the rotary brushless doubly fed machine (RBDFM), converts the secondary equivalent parameters and the control winding parameters to the power winding side, uses the direct coupling equivalent impedance to characterize the static end effect, and uses the dynamic end effect coefficient K e The secondary equivalent impedance parameters are corrected to characterize the dynamic end effect. However, when characterizing the dynamic end effect, the concentric cage parameters of this method are obtained by finite element simulation fitting, not the actual concentric cage parameters, which leads to the dynamic end effect coefficient K e The dynamic end effects cannot be accurately characterized, and therefore, the steady-state equivalent model of NLS-LDFM cannot be accurately constructed. Summary of the invention

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a method and application for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor, so as to solve the technical problem that the prior art cannot accurately construct a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor.

[0006] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor, comprising:

[0007] Under the condition of ignoring the edge effect, the voltage vector of any phase primary winding of the concentric cage secondary linear doubly fed machine is constructed. With the current vector And the relational expression of impedance matrix R+jX The impedance matrix includes: resistance matrix R and reactance matrix X; j is the imaginary number symbol;

[0008] Using the static end effect equivalent impedance matrix Z av The impedance matrix in the relational expression is corrected to obtain the first corrected expression:

[0009] Among them, Z av is a square matrix of order 2+M; M is the number of cage rings of a nest of concentric cage secondary linear doubly fed motor; Z avp is the equivalent impedance of the static end effect of the power winding; Z avc The conjugate of Z avc To control the equivalent impedance of the static end effect of the winding;

[0010] Using the dynamic end effect equivalent impedance matrix Z eff The impedance matrix in the first correction expression is corrected to obtain the second correction expression: As a steady-state equivalent model of a concentric cage secondary linear doubly-fed machine;

[0011] Among them, Z eff is a square matrix of order 2+M; Z effi is the dynamic end effect equivalent impedance of the i-th cage ring of the concentric cage secondary linear doubly fed machine.

[0012] Further preferably, the dynamic end effect equivalent impedance of the i-th cage ring of the concentric cage secondary linear doubly-fed motor is:

[0013]

[0014] Among them, R seci is the resistance of the ith cage ring; the leakage reactance of the ith cage ring is X secσi =ω sec L secσi ;ω sec is the angular frequency of the cage current; L secσi is the leakage inductance of the i-th cage ring; the dynamic end effect equivalent resistance in parallel on the i-th secondary concentric cage of the motor Z seci =R seci +jX secσi ; T v =L / v sec is the motion period, L is the longitudinal length of the motor primary core, v sec is the movement speed of the motor concentric cage; T seci is the time constant of the zero-state response process of the ith cage ring.

[0015] Further preferably, when the control winding in the concentric cage secondary linear double-fed motor forms a path,

[0016]

[0017] When the control winding in the concentric cage secondary linear doubly fed motor is disconnected,

[0018] Z avp =jX pavm

[0019] When the power winding in the concentric cage secondary linear doubly fed motor forms a path,

[0020]

[0021] When the power winding in the concentric cage secondary linear doubly fed motor is disconnected,

[0022] Z avc =jX cavm

[0023] Among them, the pulsating magnetic field excitation inductance of the power winding is X pavm =ω p L pavm ;ω p is the current angular frequency of the power winding; L pavm is the pulsating magnetic field excitation inductance of the power winding; the resistance connected in parallel to the direct coupling equivalent impedance of the pulsating magnetic field excitation inductance of the power winding y 1p and 1c N is the pitch of the power winding and the control winding respectively; φp and N φc are the total number of series turns of each phase of the power winding and the control winding respectively; R c is the phase resistance of the control winding; the reactance X is the direct coupling equivalent impedance connected in parallel with the pulsating magnetic field excitation inductance of the power winding av,c =ω p L av,c ; L cσ To control the phase leakage inductance of the winding, L cm is the fundamental excitation inductance in the single-phase equivalent circuit of the control winding; the pulsating magnetic field excitation inductance of the control winding X cavm =ω c L cavm ;ω c is the current angular frequency of the control winding; L cavm The pulsating magnetic field excitation inductance of the control winding is connected in parallel to the direct coupling equivalent impedance of the pulsating magnetic field excitation inductance of the control winding. Rp is the phase resistance of the power winding; the reactance X connected in parallel to the direct coupling equivalent impedance of the control winding pulsating magnetic field excitation inductance av,p =ω c L av,p ; L pσ is the phase leakage inductance of the power winding, L pm is the fundamental excitation inductance in the single-phase equivalent circuit of the power winding.

[0024] Further preferably, the pulsating magnetic field excitation inductance L of the power winding and the control winding is pavm and L cavm They are:

[0025]

[0026]

[0027] Among them, μ0 is the vacuum magnetic permeability, W is the equivalent stacking thickness of the motor silicon steel sheet, K av is the motor pulsation coefficient, L is the longitudinal length of the motor primary core, Z is the number of motor slots, δ e is the equivalent air gap length.

[0028] Further preferably, the voltage vector of the primary winding of the xth phase of the concentric cage secondary linear doubly fed motor is Current vector The resistance matrix R and reactance matrix X are:

[0029]

[0030]

[0031] Among them, x phase is phase A, phase B or phase C; voltage vector and the current vector Both are 2+M dimensional vectors; the resistance matrix R and reactance matrix X are both 2+M order square matrices; is the phase voltage of the xth phase of the motor power winding; is the conjugate of the phase voltage of the xth phase of the motor control winding; is the phase current of the xth phase of the motor power winding; is the conjugate of the phase current of the xth phase of the motor control winding; is the current from the first cage ring to the Mth cage ring of the first nest of the motor secondary; R pwx is the phase resistance of the xth phase of the motor power winding; R cwx is the phase resistance of the xth phase of the control winding; R sec1,1 ……R sec1,M is the resistance from the first cage ring to the Mth cage ring of the first nest of the motor secondary; ωpw is the angular frequency of the motor power winding current; ω cw is the motor control winding current angular frequency; ω sec is the angular frequency of the motor cage current; L pσ is the leakage inductance of the motor power winding; L cσ is the leakage inductance of the motor control winding; L 1σ ...L Mσ is the leakage inductance from the first cage ring to the Mth cage ring of the first nest of the motor; m pw is the phase number of the motor power winding; m cw is the phase number of the motor control winding; L p L is the fundamental self-inductance of each phase of the motor power winding; c It is the fundamental self-inductance of each phase winding of the motor control winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the power winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the control winding; N is the number of nests of the motor concentric cage; L1…L M is the self-inductance from the first cage ring to the Mth cage ring of the first nest of the motor; is the mutual inductance of the i-th and j-th cage rings of the first nest; the single-phase conversion coefficient of the i-th cage ring of the first nest of the motor L is the longitudinal length of the primary core of the motor; τ i is the span of the ith cage ring.

[0032] In a second aspect, the present invention provides a method for calculating electromagnetic parameters of a concentric cage secondary linear doubly-fed motor, comprising:

[0033] The structural parameters of the concentric cage secondary linear doubly fed motor are substituted into its steady-state equivalent model to solve the electromagnetic parameters of the concentric cage secondary linear doubly fed motor.

[0034] Among them, the steady-state equivalent model is constructed using the steady-state equivalent model construction method of the concentric cage secondary linear doubly-fed motor provided by the first aspect of the present invention.

[0035] In a third aspect, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory stores a computer program, and the processor executes the method provided in the first aspect or the second aspect of the present invention when executing the computer program.

[0036] In a fourth aspect, the present invention further provides a computer-readable storage medium, which includes a stored computer program, wherein when the computer program is executed by a processor, the device where the storage medium is located is controlled to execute the method provided in the first aspect or the second aspect of the present invention.

[0037] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program or computer instructions, which, when executed by a processor, implements the method provided in the first aspect or the second aspect of the present invention.

[0038] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0039] 1. The present invention provides a method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly fed motor. First, under the condition of ignoring the end effect, the relationship expression between the voltage vector and the current vector and the impedance matrix of the primary winding of any phase of the concentric cage secondary linear doubly fed motor is constructed. Then, the steady-state equivalent model of the concentric cage secondary linear doubly fed motor is obtained after correction using the equivalent impedance matrix representing the extra power consumed by the static end effect and the dynamic end effect. In this process, the present invention makes full use of the structural information of the concentric cage secondary linear doubly fed motor, and uses the actual concentric cage parameters to construct the dynamic end effect equivalent impedance matrix, which can more accurately construct the steady-state equivalent model of the concentric cage secondary linear doubly fed motor.

[0040] 2. The method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor provided by the present invention can characterize the direct relationship between the motor structural parameters and the concentric cage electromagnetic parameters, and the secondary conversion parameters of the steady-state equivalent model do not depend on the FEA finite element results, but can be directly obtained through the structural parameters of the motor, which can guide the design and analysis of the concentric cage secondary linear doubly-fed motor more simply and conveniently. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A flowchart of a method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor provided by an embodiment of the present invention;

[0042] Figure 2 A schematic diagram of the overall structure of a concentric cage secondary linear doubly-fed motor provided in an embodiment of the present invention;

[0043] Figure 3 A schematic diagram of a concentric cage secondary structure of a concentric cage secondary linear doubly-fed motor provided in an embodiment of the present invention;

[0044] Figure 4 A schematic diagram of direct coupling reduced impedance provided by an embodiment of the present invention;

[0045] Figure 5 A schematic diagram of a dynamic end effect resistor provided by an embodiment of the present invention;

[0046] Figure 6 A circuit diagram of a zero-state response process of an i-th cage ring provided by an embodiment of the present invention;

[0047] Figure 7 A comparison chart of the electromagnetic thrust analysis results and the finite element analysis simulation results of the steady-state equivalent model provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] In the present invention, the terms "first", "second", etc. (if any) in the present invention and the accompanying drawings are used to distinguish similar objects but not necessarily to describe a specific order or sequence.

[0050] In order to achieve the above-mentioned object, in the first aspect, the present invention provides a method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor, such as Figure 1 As shown, including:

[0051] A1. Under the condition of ignoring the edge effect, construct the voltage vector of any phase primary winding of the concentric cage secondary linear doubly fed machine With the current vector And the relational expression of impedance matrix R+jX The impedance matrix includes: resistance matrix R and reactance matrix X; j is the imaginary number symbol;

[0052] The overall structure of the concentric cage secondary linear doubly fed motor and the schematic diagram of its concentric cage secondary structure are shown in Figure 2. Figure 2 and Figure 3 As shown, under the condition of ignoring the edge effect, the concentric cage secondary linear doubly fed motor is equivalent to the concentric cage brushless doubly fed induction motor. In an optional implementation, according to the voltage vector of any phase primary winding in the concentric cage brushless doubly fed induction motor With the current vector The relationship expression of the impedance matrix R+jX is used to construct the expression corresponding to the concentric cage secondary linear double-fed machine. The constructed relationship expression is:

[0053]

[0054] Among them, x phase is phase A, phase B or phase C; voltage vector and the current vector Both are 2+M dimensional vectors; M is the number of cage rings in a nest of the concentric cage secondary linear doubly fed machine; the resistance matrix R and the reactance matrix X are both 2+M order square matrices; is the phase voltage of the xth phase of the motor power winding; is the conjugate of the phase voltage of the xth phase of the motor control winding; is the phase current of the xth phase of the motor power winding; is the conjugate of the phase current of the xth phase of the motor control winding; is the current from the first cage ring to the Mth cage ring of the first nest of the motor secondary; R pwx is the phase resistance of the xth phase of the motor power winding; R cwx is the phase resistance of the xth phase of the control winding; R sec1,1 ……R sec1,M is the resistance from the first cage ring to the Mth cage ring of the first nest of the motor secondary; ω pw is the angular frequency of the motor power winding current; ω cw is the motor control winding current angular frequency; ω sec is the angular frequency of the motor cage current; L pσ is the leakage inductance of the motor power winding; L cσ is the leakage inductance of the motor control winding; L 1σ ...L Mσ is the leakage inductance from the first cage ring to the Mth cage ring of the first nest of the motor; m pw is the phase number of the motor power winding; m cw is the phase number of the motor control winding; L p L is the fundamental self-inductance of each phase of the motor power winding; c It is the fundamental self-inductance of each phase winding of the motor control winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the power winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the control winding; N is the number of nests of the motor concentric cage; L1…L M is the self-inductance from the first cage ring to the Mth cage ring of the first nest of the motor; is the mutual inductance of the i-th and j-th cage rings of the first nest; the single-phase conversion coefficient of the i-th cage ring of the first nest of the motor L is the longitudinal length of the primary core of the motor; τ i is the span of the ith cage ring.

[0055] A2. Using the static end effect equivalent impedance matrix Z av The impedance matrix in the relational expression is corrected to obtain the first corrected expression:

[0056] The static end effect refers to the fact that the air gap magnetomotive force generated by the primary winding contains a pulsating component due to the disconnection of both ends of the iron core. The existence of the pulsating magnetic field causes the mutual inductance asymmetry between the three-phase inductors and direct coupling between the two sets of windings. In order to minimize the degree of direct coupling, the winding scheme of NLS-LDFM uses two sets of single-layer full-pitch windings, and the two sets of windings transfer power only through direct coupling of the pulsating magnetic field.

[0057] When the control winding is disconnected, the pulsating magnetic field is only established by the power winding; when the power winding is disconnected, the pulsating magnetic field is only established by the control winding; in the corresponding scenario, the pulsating magnetic field excitation inductance L of the power winding and the control winding is pavm and L cavm They are:

[0058]

[0059]

[0060] Among them, μ0 is the vacuum magnetic permeability, W is the equivalent stacking thickness of the motor silicon steel sheet, K av is the motor pulsation coefficient, L is the longitudinal length of the motor primary core, y 1p and 1c are the pitches of the power winding and the control winding, N φp and N φc are the total number of series turns of each phase of the power winding and the control winding, Z is the number of motor slots, δ e is the equivalent air gap length.

[0061] When the control winding or the power winding forms a path, direct coupling will induce a direct coupling electromotive force in the two sets of windings. Since the induced frequency is different from the fundamental frequency of the corresponding winding, the power generated by the direct coupling induced electromotive force can be averaged to each phase of the primary winding according to the superposition principle, which is equivalent to connecting a direct coupling conversion impedance in parallel to the pulsating magnetic field excitation inductance, such as Figure 4 The resistor R connected in parallel with the direct coupling equivalent impedance of the power winding pulsating magnetic field excitation inductance is shown as follows. av,c and inductor L av,c :

[0062]

[0063] In the formula, R c is the phase resistance of the control winding; L cσ To control the phase leakage inductance of the winding, L cm is the fundamental excitation inductance in the single-phase equivalent circuit of the control winding.

[0064] The resistor R connected in parallel to the direct coupling equivalent impedance of the control winding pulsating magnetic field excitation inductance av,p and inductor Lav,p for:

[0065]

[0066] In the formula, R p is the phase resistance of the power winding, L pσ is the phase leakage inductance of the power winding, L pm is the fundamental excitation inductance in the single-phase equivalent circuit of the power winding.

[0067] Static end effect equivalent impedance Z of power winding avp The static end effect equivalent impedance of the control winding is Z avc They are:

[0068]

[0069]

[0070] Among them, the pulsating magnetic field excitation inductance of the power winding is X pavm =ω p L pavm ;ω p is the current angular frequency of the power winding; the reactance X is the direct coupling equivalent impedance of the excitation inductance of the power winding pulsating magnetic field in parallel av,c =ω p L av,c ;ω c is the current angular frequency of the control winding; the pulsating magnetic field excitation inductance X of the control winding cavm =ω c L cavm ; The reactance X connected in parallel to the direct coupling equivalent impedance of the control winding pulsating magnetic field excitation inductance av,p =ω c L av,p .

[0071] From this we can get the static end effect equivalent impedance matrix Z av for:

[0072]

[0073] Among them, Z av is a square matrix of order 2+M; Z avc The conjugation of.

[0074] A3. Using dynamic end effect equivalent impedance matrix Z eff The impedance matrix in the first correction expression is corrected to obtain the second correction expression: As a steady-state equivalent model of a concentric cage secondary linear doubly-fed machine;

[0075] The dynamic end effect refers to the zero-state response of the cage ring current during the process of the secondary entering and exiting the air gap. The current needs to go through a transition process to change from one stable state to another. After analysis, it can be seen that the cage ring current has a forced component and a free component. The forced component corresponds to the steady-state current component of the concentric cage rotating brushless double-fed motor, while the free component corresponds to the transient current generated when the cage ring enters and exits the air gap. The extra power loss of this transient current on the secondary cage ring resistance is averaged to each secondary cage ring, which is equivalent to connecting a dynamic end effect equivalent resistor in parallel to the secondary concentric cage, such as Figure 5 shown.

[0076] Figure 6 The circuit diagram represents the zero-state response process of the i-th cage ring, where R seci is the resistance of the ith cage ring, L secσi is the leakage inductance of the ith cage ring. seci is the electromotive force generated by the secondary cage ring cutting the air gap magnetic field. List the zero-state response equation and solve the cage ring transient current to be:

[0077]

[0078]

[0079] Among them, p is the differential operator, i secq is the mandatory component, i secz is the free component, is the electromotive force E seci The initial phase angle, is the impedance angle of the cage ring, T seci is the time constant of the circuit (i.e., the time constant of the zero-state response process of the ith cage loop).

[0080] The velocity of the concentric cage is v sec , assuming that the concentric cage enters the air gap in a zero current state after exiting the air gap, the forced component corresponds to the steady-state current component of the concentric cage rotating brushless doubly-fed motor, and its power consumption is not affected by the dynamic edge effect, while the free component corresponds to the transient current generated when the cage ring enters and exits the air gap, so it can be regarded as a harmonic current, and it runs for an infinite number of cycles (T v =L / v sec , L is the longitudinal length of the primary iron core of the motor), the power generated by the harmonic current in the secondary concentric cage can be expressed as:

[0081]

[0082]

[0083] Among them, I iz The free component is equivalent to the effective value of the harmonic current, Pseciz is the average power lost by the harmonic current on the i-th secondary cage ring resistance. Then the dynamic end effect equivalent resistance R effi It can be expressed as:

[0084]

[0085] Among them, Z seci =R seci +jX secσi .

[0086] The dynamic end effect equivalent impedance of the i-th cage ring of the concentric cage secondary linear doubly fed machine is:

[0087]

[0088] Among them, the leakage reactance of the i-th cage ring is X secσi =ω sec L secσi ;ω sec is the angular frequency of the cage current.

[0089] Thus, the dynamic end effect equivalent impedance matrix Z eff for:

[0090]

[0091] Among them, Z eff It is a square matrix of order 2+M.

[0092] In summary, after the impedance matrix representing the extra power consumed by the static end effect and the dynamic end effect is corrected, the steady-state equivalent model of the concentric cage secondary linear doubly fed machine is finally obtained.

[0093] In order to further illustrate the method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor provided by the present invention, a specific embodiment is described in detail below:

[0094] In this embodiment, the parameters shown in Table 1 are taken as an example to illustrate the accuracy and optimization effect of the proposed steady-state equivalent model.

[0095] Table 1

[0096]

[0097] The method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor provided by the present invention comprises the following steps:

[0098] Firstly, under the condition of ignoring the edge effect, the relationship expression between the voltage vector, current vector and impedance matrix of any phase primary winding of the concentric cage secondary linear doubly fed machine is constructed.

[0099] Specifically, a voltage equation retaining the x-phase primary winding is constructed, that is, the above relational expression:

[0100]

[0101] Secondly, the impedance matrix in the relational expression is corrected using the static end effect equivalent impedance matrix to obtain the first corrected expression;

[0102] When the control winding is disconnected, the pulsating magnetic field is only established by the power winding; when the power winding is disconnected, the pulsating magnetic field is only established by the control winding; in the corresponding scenario, the pulsating magnetic field excitation inductance L of the power winding and the control winding is pavm and L cavm They are:

[0103]

[0104]

[0105] The resistor R connected in parallel with the direct coupling equivalent impedance of the power winding pulsating magnetic field excitation inductance av,c and inductor L av,c They are:

[0106]

[0107] The resistor R connected in parallel to the direct coupling equivalent impedance of the control winding pulsating magnetic field excitation inductance av,p and inductor L av,p They are:

[0108]

[0109] The static end effect equivalent impedance Z of the power winding can be obtained avp The static end effect equivalent impedance of the control winding is Z avc They are:

[0110]

[0111]

[0112] Then, the impedance matrix in the first equation is modified using the dynamic end effect equivalent impedance matrix to obtain a steady-state model;

[0113] Taking the dynamic end effect equivalent impedance calculation process of the first cage ring as an example, when the control winding is short-circuited, the power winding is connected to the industrial frequency AC with an effective line voltage of 180V, and the secondary concentric cage runs at a speed of 5m / s, the equivalent impedance of the other cage rings can be obtained by the same token, which will not be repeated here.

[0114] The dynamic end effect equivalent resistance of the first cage ring is:

[0115]

[0116] Then the dynamic end effect equivalent impedance of the first cage ring is:

[0117]

[0118] Finally, the steady-state model is used to design or optimize the structural parameters of the concentric cage secondary linear double-fed induction motor.

[0119] Under the condition of cascade asynchronous operation (the control winding is short-circuited, and the power winding is connected to the industrial frequency AC with an effective line voltage of 180V), the electromagnetic thrust of the motor is calculated and analyzed, such as Figure 7 As shown in the figure, the proposed equivalent model is basically consistent with the FEA finite element results.

[0120] In a second aspect, the present invention provides a method for calculating electromagnetic parameters of a concentric cage secondary linear doubly-fed motor, comprising:

[0121] The structural parameters of the concentric cage secondary linear doubly fed motor are substituted into its steady-state equivalent model to solve the electromagnetic parameters of the concentric cage secondary linear doubly fed motor.

[0122] Among them, the steady-state equivalent model is constructed using the steady-state equivalent model construction method of the concentric cage secondary linear doubly-fed motor provided by the first aspect of the present invention.

[0123] It should be noted that the above electromagnetic parameters include the reactance, resistance, etc. of the motor.

[0124] The related technical scheme is the same as the method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor provided in the first aspect of the present invention, and will not be described in detail here.

[0125] In a third aspect, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory stores a computer program, and the processor executes the method provided in the first aspect or the second aspect of the present invention when executing the computer program.

[0126] The related technical solutions are the same as the steady-state equivalent model construction method of the concentric cage secondary linear doubly fed motor provided in the first aspect of the present invention and the electromagnetic parameter calculation method of the concentric cage secondary linear doubly fed motor provided in the second aspect, which will not be described in detail here.

[0127] In a fourth aspect, the present invention further provides a computer-readable storage medium, which includes a stored computer program, wherein when the computer program is executed by a processor, the device where the storage medium is located is controlled to execute the method provided in the first aspect or the second aspect of the present invention.

[0128] The related technical solutions are the same as the steady-state equivalent model construction method of the concentric cage secondary linear doubly fed motor provided in the first aspect of the present invention and the electromagnetic parameter calculation method of the concentric cage secondary linear doubly fed motor provided in the second aspect, which will not be described in detail here.

[0129] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program or computer instructions, which, when executed by a processor, implements the method provided in the first aspect or the second aspect of the present invention.

[0130] The related technical solutions are the same as the steady-state equivalent model construction method of the concentric cage secondary linear doubly fed motor provided in the first aspect of the present invention and the electromagnetic parameter calculation method of the concentric cage secondary linear doubly fed motor provided in the second aspect, which will not be described in detail here.

[0131] The related technical solutions are the same as the steady-state equivalent model construction method of the concentric cage secondary linear doubly fed motor provided in the first aspect of the present invention and the electromagnetic parameter calculation method of the concentric cage secondary linear doubly fed motor provided in the second aspect, which will not be described in detail here.

[0132] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for constructing a steady-state equivalent model of a concentric cage secondary linear doubly-fed motor, characterized in that: include: Under the condition of ignoring the edge effect, the voltage vector of any phase primary winding of the concentric cage secondary linear doubly fed machine is constructed. With the current vector And the relational expression of impedance matrix R+jX The impedance matrix includes: a resistance matrix R and a reactance matrix X; j is an imaginary number symbol; Using the static end effect equivalent impedance matrix Z av The impedance matrix in the relational expression is corrected to obtain the first corrected expression: Among them, Z av is a square matrix of order 2+M; M is the number of cage rings of a nest of concentric cage secondary linear doubly fed motor; Z avp is the equivalent impedance of the static end effect of the power winding; Z avc The conjugate of Z avc To control the equivalent impedance of the static end effect of the winding; Using the dynamic end effect equivalent impedance matrix Z eff The impedance matrix in the first correction expression is corrected to obtain the second correction expression: As a steady-state equivalent model of a concentric cage secondary linear doubly-fed machine; Among them, Z eff is a square matrix of order 2+M; Z effi is the dynamic end effect equivalent impedance of the i-th cage ring of the concentric cage secondary linear doubly fed machine.

2. The method for constructing a steady-state equivalent model according to claim 1, characterized in that: The dynamic end effect equivalent impedance Z of the i-th cage ring of the concentric cage secondary linear doubly fed machine effi for: Among them, R seci is the resistance of the ith cage ring; the leakage reactance of the ith cage ring is X secσi =ω sec L secσi ;ω sec is the angular frequency of the cage current; L secσi is the leakage inductance of the i-th cage ring; the dynamic end effect equivalent resistance in parallel on the i-th secondary concentric cage of the motor Z seci =R seci +jX secσi ; T v =L / v sec is the motion period, L is the longitudinal length of the motor primary core, v sec is the movement speed of the motor concentric cage; T seci is the time constant of the zero-state response process of the ith cage ring.

3. The method for constructing a steady-state equivalent model according to claim 1, characterized in that: When the control winding in the concentric cage secondary linear doubly fed motor forms a path, When the control winding in the concentric cage secondary linear doubly fed motor is disconnected, Z avp =jX pavm When the power winding in the concentric cage secondary linear doubly fed motor forms a path, When the power winding in the concentric cage secondary linear doubly fed motor is disconnected, Z avc =jX cavm Among them, the pulsating magnetic field excitation inductance of the power winding is X pavm =ω p L pavm ;ω p is the current angular frequency of the power winding; L pavm is the pulsating magnetic field excitation inductance of the power winding; the resistance connected in parallel with the direct coupling equivalent impedance of the pulsating magnetic field excitation inductance of the power winding y 1p and 1c are the pitches of the power winding and the control winding respectively; N φp and N φc are the total number of series turns of each phase of the power winding and the control winding respectively; R c is the phase resistance of the control winding; the reactance X is the direct coupling equivalent impedance connected in parallel with the pulsating magnetic field excitation inductance of the power winding av,c =ω p L av,c ; L cσ To control the phase leakage inductance of the winding, L cm is the fundamental excitation inductance in the single-phase equivalent circuit of the control winding; the pulsating magnetic field excitation inductance of the control winding X cavm =ω c L cavm ;ω c is the current angular frequency of the control winding; L cavm The pulsating magnetic field excitation inductance of the control winding is connected in parallel to the direct coupling equivalent impedance of the pulsating magnetic field excitation inductance of the control winding. R p is the phase resistance of the power winding; the reactance X connected in parallel to the direct coupling equivalent impedance of the control winding pulsating magnetic field excitation inductance av,p =ω c L av,p ; L pσ is the phase leakage inductance of the power winding, L pm is the fundamental excitation inductance in the single-phase equivalent circuit of the power winding.

4. The method for constructing a steady-state equivalent model according to claim 3, characterized in that: Pulsating magnetic field excitation inductance L of power winding and control winding pavm and L cavm They are: Among them, μ0 is the vacuum magnetic permeability, W is the equivalent stacking thickness of the motor silicon steel sheet, K av is the motor pulsation coefficient, L is the longitudinal length of the motor primary core, Z is the number of motor slots, δ e is the equivalent air gap length.

5. The method for constructing a steady-state equivalent model according to any one of claims 1 to 4, characterized in that: The voltage vector of the primary winding of the xth phase of the concentric cage secondary linear doubly fed machine Current vector The resistance matrix R and reactance matrix X are: Among them, x phase is phase A, phase B or phase C; voltage vector and the current vector Both are 2+M dimensional vectors; the resistance matrix R and reactance matrix X are both 2+M order square matrices; is the phase voltage of the xth phase of the motor power winding; is the conjugate of the phase voltage of the xth phase of the motor control winding; is the phase current of the xth phase of the motor power winding; is the conjugate of the phase current of the xth phase of the motor control winding; is the current from the first cage ring to the Mth cage ring of the first nest of the motor secondary; R pwx is the phase resistance of the xth phase of the motor power winding; R cwx is the phase resistance of the xth phase of the control winding; R sec1,1 ……R sec1,M is the resistance from the first cage ring to the Mth cage ring of the first nest of the motor secondary; ω pw is the angular frequency of the motor power winding current; ω cw is the motor control winding current angular frequency; ω sec is the angular frequency of the motor cage current; L pσ is the leakage inductance of the motor power winding; L cσ is the leakage inductance of the motor control winding; L 1σ ...L Mσ is the leakage inductance from the first cage ring to the Mth cage ring of the first nest of the motor; m pw is the phase number of the motor power winding; m cw is the phase number of the motor control winding; L p L is the fundamental self-inductance of each phase of the motor power winding; c It is the fundamental self-inductance of each phase winding of the motor control winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the power winding; is the mutual inductance between the i-th cage ring of the first nest of the motor and the x-th phase of the control winding; N is the number of nests of the motor concentric cage; L1…L M is the self-inductance from the first cage ring to the Mth cage ring of the first nest of the motor; is the mutual inductance of the i-th and j-th cage rings of the first nest; the single-phase conversion coefficient of the i-th cage ring of the first nest of the motor L is the longitudinal length of the primary core of the motor; τ i is the span of the ith cage ring.

6. A method for calculating electromagnetic parameters of a concentric cage secondary linear doubly-fed motor, characterized in that: include: The structural parameters of the concentric cage secondary linear doubly fed motor are substituted into its steady-state equivalent model to solve the electromagnetic parameters of the concentric cage secondary linear doubly fed motor. Wherein, the steady-state equivalent model is constructed by using the steady-state equivalent model construction method of the concentric cage secondary linear doubly-fed motor described in any one of claims 1-5.

7. An electronic device, characterized in that: include: A memory and a processor, wherein the memory stores a computer program, and the processor executes the method according to any one of claims 1 to 6 when executing the computer program.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored computer program, wherein when the computer program is executed by a processor, the device where the storage medium is located is controlled to execute the method according to any one of claims 1 to 6.

9. A computer program product, characterized in that The method comprises a computer program or a computer instruction, and when the computer program or the computer instruction is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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