CN109120199A

CN109120199A - A kind of method and device of the d axle inductance of determining variable-frequency motor

Info

Publication number: CN109120199A
Application number: CN201810925112.6A
Authority: CN
Inventors: 涂小平; 陈跃; 陈搏
Original assignee: Sichuan Hongmei Intelligent Technology Co Ltd
Current assignee: Sichuan Hongmei Intelligent Technology Co Ltd
Priority date: 2018-08-14
Filing date: 2018-08-14
Publication date: 2019-01-01

Abstract

The present invention provides a kind of method and device of the d axle inductance of determining variable-frequency motor, this method, comprising: the IGBT that PWM wave is acted on to variable-frequency motor, by controlling the duty ratio of PWM wave, by the rotor fixed position of variable-frequency motor to the direction with α axis at first angle；According to the information of PWM wave, the information of IGBT and the first operation information, the phase resistance of variable-frequency motor is determined；After controlling variable-frequency motor electric discharge, PWM wave is acted on into IGBT, the duty ratio by controlling PWM wave determines the second operation information of variable-frequency motor by rotor fixed position to the direction with α axis at second angle；After controlling variable-frequency motor electric discharge, PWM wave is acted on into IGBT, by rotor fixed position to the direction with α axis at second angle, determines the third operation information of variable-frequency motor；According to phase resistance, the second operation information and third operation information, the d axle inductance of variable-frequency motor is determined.The present invention can more accurately determine d axle inductance.

Description

A kind of method and device of the d axle inductance of determining variable-frequency motor

Technical field

The present invention relates to field of mechanical technique, in particular to a kind of method and device of the d axle inductance of determining variable-frequency motor.

Background technique

During using variable-frequency motor, it is often necessary to use the d axle inductance of variable-frequency motor.

In the prior art, when determining d axle inductance, the PWM wave for controlling variable-frequency motor operation immobilizes, in this way, During determining d axle inductance, can there is a problem of that the electric current in electrical-coil is excessive or too small.If the electricity of variable-frequency motor Hinder it is larger, electric current in electrical-coil is too small can cause can not by rotor fixed position to 0 ° or 270 ° equal target positions the problem of.Such as The resistance of fruit variable-frequency motor is smaller, and the electric current in electrical-coil crosses conference, and there are variable-frequency motor demagnetization risks.These problems all make The d axle inductance inaccuracy that must be determined.

As can be seen from the above description, can not accurately determine d axle inductance in the prior art.

Summary of the invention

The embodiment of the invention provides a kind of method and devices of the d axle inductance of determining variable-frequency motor, can be more accurate Determine the d axle inductance of variable-frequency motor in ground.

On the one hand, the embodiment of the invention provides a kind of methods of the d axle inductance of determining variable-frequency motor, comprising:

PWM (Pulse Width Modulation, pulse width modulation) wave is acted on to the IGBT of variable-frequency motor (Insulated Gate Bipolar Transistor, insulated gate bipolar transistor), by controlling accounting for for the PWM wave Empty ratio, by the rotor fixed position of the variable-frequency motor to the direction with α axis in the fixed coordinates axis at first angle；

The first operation information for determining the information of the PWM wave, the information of the IGBT and the variable-frequency motor, according to institute The information of PWM wave, the information of the IGBT and first operation information are stated, determines the phase resistance of the variable-frequency motor；

The variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, passes through control The duty ratio of the PWM wave determines the of the variable-frequency motor by the rotor fixed position to the direction with α axis at second angle Two operation informations；

The variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, described will be turned Son navigates to the direction with α axis at the second angle, determines the third operation information of the variable-frequency motor；

According to the phase resistance, second operation information and the third operation information, the d of the variable-frequency motor is determined Axle inductance.

Further,

It include: the direction of the target phase of the variable-frequency motor at the direction of first angle with α axis in the fixed coordinates axis；

The target of the variable-frequency motor mutually includes: the U phase of the variable-frequency motor, the V phase of the variable-frequency motor and the change Any one in the W phase of frequency motor；

The IGBT that PWM wave is acted on to variable-frequency motor, by controlling the duty ratio of the PWM wave, by the frequency conversion The rotor fixed position of motor is to the direction with α axis in the fixed coordinates axis at first angle, comprising:

The corresponding target phase PWM wave of the target is inputted to the IGBT in real time；

Real-time detection flows into the first coil electric current of the electrical-coil；

When detecting the first coil electric current less than the first predetermined current, increase the duty of the target phase PWM wave Than；

When detecting that the first coil electric current is greater than first predetermined current, reduce the target phase PWM wave Duty ratio；

When detecting that the first coil electric current is equal to first predetermined current, the target phase PWM wave is kept Duty ratio is constant, controls the variable-frequency motor using the target phase PWM wave and runs the first preset duration, pre- by described first If the rotor reaches the direction with α axis at the first angle after duration.

Further,

First operation information of the information of the determination PWM wave, the information of the IGBT and the variable-frequency motor, root According to the information of the PWM wave, the information of the IGBT and first operation information, the phase resistance of the variable-frequency motor is determined, Include:

Determine the duty ratio in first preset duration of the target phase PWM wave, the week of the target phase PWM wave Phase；

Determine the dead time of the IGBT, and, the afterflow two of the forward conduction voltage and the IGBT of the IGBT The sum of pole pipe forward conduction voltage drop；

The first coil electric current of the determining electrical-coil described at the time of terminating first preset duration and the frequency conversion The bus voltage value of motor；

According to formula one, the phase resistance of the variable-frequency motor, the formula one are determined are as follows:

Wherein, r is the phase resistance, E_dcFor the bus of the variable-frequency motor described at the time of terminating first preset duration Voltage value, T_aFor the duty ratio in first preset duration of the target phase PWM wave, T_dFor the IGBT dead zone when Between, V_sFor the forward conduction voltage of the IGBT, V_dFor the freewheeling diode forward conduction voltage drop of the IGBT, T is the target The period of phase PWM wave, I₀For the first coil electric current of the electrical-coil described at the time of terminating first preset duration.

Further,

It is described that the PWM wave is acted on into the IGBT, by controlling the duty ratio of the PWM wave, the rotor is determined Position is arrived with α axis into the direction of second angle, comprising:

For the U phase of the variable-frequency motor, U phase PWM wave is inputted to the IGBT in real time, for the V of the variable-frequency motor Phase inputs V phase PWM wave to the IGBT in real time, for the W phase of the variable-frequency motor, inputs W phase PWM to the IGBT in real time Wave；

By controlling the duty ratio of the U phase PWM wave, the duty of the duty ratio of the V phase PWM wave and the W phase PWM wave Than control electric current flows into the electrical-coil from the W phase of the variable-frequency motor and flows out from the V phase of the variable-frequency motor；

Real-time detection flows into the second coil current of the electrical-coil of the variable-frequency motor；

When detecting that second coil current is greater than the second predetermined current, increase the duty ratio of the V phase PWM wave, Reduce the duty ratio of the W phase PWM wave；

When detecting that second coil current is less than second predetermined current, reduce the duty of the V phase PWM wave Than increasing the duty ratio of the W phase PWM wave；

When detecting that second coil current is equal to second predetermined current, the duty of the U phase PWM wave is kept Duty ratio than, the duty ratio of the V phase PWM wave and the W phase PWM wave is constant, utilizes the U phase PWM wave, the V phase PWM wave and the W phase PWM wave control the variable-frequency motor and run the second preset duration, the institute after second preset duration It states rotor and reaches direction with α axis at the second angle；

It is described that the PWM wave is acted on into the IGBT, by the rotor fixed position to the side with α axis at the second angle To, comprising:

Using the U phase PWM wave, the V phase PWM wave and the W phase PWM wave, the variable-frequency motor operation third is controlled Preset duration, the rotor reaches the direction with α axis at the second angle after the third preset duration, wherein institute The duty ratio for stating the duty ratio of U phase PWM wave, the duty ratio of the V phase PWM wave and the W phase PWM wave is default with described second Duty ratio corresponding in duration is identical.

Further,

Second operation information of the determination variable-frequency motor, comprising:

Determine the second coil current of the electrical-coil described at the time of terminating second preset duration；

The third operation information of the determination variable-frequency motor, comprising:

Determine the tertiary coil electric current of the electrical-coil described at the time of terminating the third preset duration；

It is described according to the phase resistance, second operation information and the third operation information, determine the variable-frequency electric The d axle inductance of machine, comprising:

According to formula two, the d axle inductance of the variable-frequency motor, the formula two are determined are as follows:

Wherein, L_dFor the d axle inductance of the variable-frequency motor, r is the phase resistance, and t is the third preset duration, I_w0For The second coil current of the electrical-coil, I at the time of terminating second preset duration_w1It is default in the end third The tertiary coil electric current of electrical-coil at the time of duration.

Further,

Further comprise: presetting the forward conduction voltage of the IGBT and the positive guide of freewheeling diode of the IGBT Corresponding relationship of the sum of the logical pressure drop with first predetermined current；

According to first predetermined current and the corresponding relationship, determine the forward conduction voltage of the IGBT with it is described The sum of freewheeling diode forward conduction voltage drop of IGBT.

Further,

The duty ratio of the duty ratio of the U phase PWM wave, the duty ratio of the V phase PWM wave and the W phase PWM wave it is initial Value is Tc/2, wherein Tc is the half in the PWM wave corresponding triangular wave carrier period.

Further,

Meet at the direction of the first angle and with α axis at the direction of the second angle with α axis: with α axis at described The direction of second angle is rotated by 90 ° arrival and α axis into the direction of the first angle counterclockwise.

Further,

The U phase of the variable-frequency motor is overlapped with the positive axis of the α axis.

On the other hand, the embodiment of the invention provides a kind of devices of the d axle inductance of determining variable-frequency motor, comprising:

First control unit, for PWM wave to be acted on to the IGBT of variable-frequency motor, by the duty for controlling the PWM wave Than by the rotor fixed position of the variable-frequency motor to the direction with α axis in the fixed coordinates axis at first angle；

Phase resistance determination unit, for determining the information of the PWM wave, the information of the IGBT and the variable-frequency motor First operation information determines the change according to the information of the PWM wave, the information of the IGBT and first operation information The phase resistance of frequency motor；

After the completion of electric discharge, the PWM wave is acted on for controlling the variable-frequency motor electric discharge for second control unit The IGBT, by the rotor fixed position to the direction with α axis at second angle, is determined by controlling the duty ratio of the PWM wave Second operation information of the variable-frequency motor；

After the completion of electric discharge, the PWM wave is acted on for controlling the variable-frequency motor electric discharge for third control unit The IGBT determines the third operation of the variable-frequency motor by the rotor fixed position to the direction with α axis at the second angle Information；

Inductance determination unit is used for according to the phase resistance, second operation information and the third operation information, really The d axle inductance of the fixed variable-frequency motor.

Further,

The first control unit, is used for:

Further,

Second control unit, execute it is described the PWM wave is acted on into the IGBT, pass through the control PWM The duty ratio of wave, by the rotor fixed position to α axis at second angle direction when, be specifically used for:

The third control unit, execute it is described the PWM wave is acted on into the IGBT, the rotor fixed position is arrived With α axis at the second angle direction when, be specifically used for:

Further,

In embodiments of the present invention, PWM wave does not immobilize, and the duty ratio of PWM wave can be according to the fortune of variable-frequency motor Market condition adjusts in real time, and the duty ratio by controlling PWM wave can realize the rotor fixed position of variable-frequency motor to the position needed Accurate positionin to rotor, and then can be according to the operation information of variable-frequency motor, the information of the information of IGBT and PWM wave, more Accurately determine out the d axle inductance of variable-frequency motor.

Detailed description of the invention

In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is the present invention Some embodiments for those of ordinary skill in the art without creative efforts, can also basis These attached drawings obtain other attached drawings.

Fig. 1 is a kind of flow chart of the method for the d axle inductance for determining variable-frequency motor that one embodiment of the invention provides；

Fig. 2 is the circuit diagram of the IGBT for variable-frequency motor that one embodiment of the invention provides a kind of；

Fig. 3 is that the fixed coordinate system that the α axis that one embodiment of the invention provides and β axis are constituted is constituted with U phase, V phase, W phase Relation schematic diagram between fixed coordinate system；

Fig. 4 is the flow chart of the method for the d axle inductance that the another kind that one embodiment of the invention provides determines variable-frequency motor；

Fig. 5 is a kind of schematic diagram of the device of the d axle inductance for determining variable-frequency motor that one embodiment of the invention provides.

Specific embodiment

In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is A part of the embodiment of the present invention, instead of all the embodiments, based on the embodiments of the present invention, those of ordinary skill in the art Every other embodiment obtained without making creative work, shall fall within the protection scope of the present invention.

As shown in Figure 1, this method can the embodiment of the invention provides a kind of method of the d axle inductance of determining variable-frequency motor With the following steps are included:

Step 101: PWM wave is acted on to the IGBT of variable-frequency motor, it, will be described by controlling the duty ratio of the PWM wave The rotor fixed position of variable-frequency motor is to the direction with α axis in the fixed coordinates axis at first angle；

Step 102: determining the first operation letter of the information of the PWM wave, the information of the IGBT and the variable-frequency motor Breath, according to the information of the PWM wave, the information of the IGBT and first operation information, determines the phase of the variable-frequency motor Resistance；

Step 103: the variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, Duty ratio by controlling the PWM wave determines the frequency conversion by the rotor fixed position to the direction with α axis at second angle Second operation information of motor；

Step 104: the variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, By the rotor fixed position to the direction with α axis at the second angle, the third operation information of the variable-frequency motor is determined；

Step 105: according to the phase resistance, second operation information and the third operation information, determining the change The d axle inductance of frequency motor.

As shown in Fig. 2, the circuit diagram of the IGBT of variable-frequency motor provided in an embodiment of the present invention a kind of.Six are shown in figure Metal-oxide-semiconductor, six freewheeling diodes and a resistance R, six metal-oxide-semiconductors are respectively: VT1, VT2, VT3, VT4, VT5, VT6；Six Freewheeling diode is respectively: D1, D2, D3, D4, D5, D6.VT1 and VT2 corresponds to the U phase of variable-frequency motor, and VT3 and VT4 correspond to frequency conversion The V phase of motor, VT5 and VT6 correspond to the W phase of variable-frequency motor.It is high when applying on the grid in metal-oxide-semiconductor for any one metal-oxide-semiconductor When level, metal-oxide-semiconductor conducting, metal-oxide-semiconductor conducting.It powers after VT1 conducting for the U phase of variable-frequency motor, is variable-frequency motor after VT3 conducting V phase power, power after VT5 conducting for the W phase of variable-frequency motor.Variable-frequency motor M is also shown in Fig. 2.

In order to more clearly come describe IGBT VT1, VT3 and VT5 state, can be carried out by way of vector Explanation.Specifically, in vector (x, y, z), x corresponds to VT1, VT1 conducting is indicated when x is 1, it is, U is conducted, when x is VT1 shutdown is indicated when 0, it is, U phase is not turned on；Y corresponds to VT3, and VT3 conducting is indicated when y is 1, it is, V is conducted, VT3 shutdown is indicated when y is 0, it is, V phase is not turned on；Z corresponds to VT5, VT5 conducting is indicated when z is 1, it is, W phase Conducting indicates VT5 shutdown when z is 0, it is, W phase is not turned on.

In addition, generally, the PWM wave that IGBT is received is by the way of three-phase complementary, when the condition for considering dead zone function Under, the PWM wave of upper and lower bridge arm is complementary and differs corresponding dead time.When VT1 conducting, VT2 is not turned on, when VT3 is connected When, VT4 is not turned on, and when VT5 conducting, VT6 is not turned on.

It in an embodiment of the present invention, include: the frequency conversion at the direction of first angle with α axis in the fixed coordinates axis The direction of the target phase of motor；

In embodiments of the present invention, the first coil of electrical-coil is controlled by controlling the duty ratio of target phase PWM wave Electric current, to reach the first predetermined current.

In embodiments of the present invention, after the duty ratio every time to target phase PWM wave is adjusted, mesh adjusted is utilized Mark phase PWM wave is input to IGBT.

In embodiments of the present invention, it can be the direction of any one phase of variable-frequency motor at the direction of first angle with α axis. Wherein, the U phase, V phase of variable-frequency motor are also fixed coordinate system with the coordinate system that W phase is constituted.

For example, the U phase of variable-frequency motor is overlapped with the positive axis of α axis, then, when the direction with α axis at first angle For variable-frequency motor U phase when, first angle be 0 °, when with α axis at first angle direction be variable-frequency motor V phase when, first Angle be 120 °, when with α axis at first angle direction be variable-frequency motor W phase when, first angle be 240 °.Here first Angle, which refers to, rotates counterclockwise to the angle passed through with α axis at the direction of first angle by α axis.

In embodiments of the present invention, by inputting the corresponding target phase PWM wave of target to IGBT, so that in variable-frequency motor Only target mutually has electric current inflow.For example, target is mutually U phase, then, it is right to the corresponding U phase PWM wave of IGBT input U For IGBT, the state switched on the grid of the corresponding VT1 of U for high level and low level, and the grid of the corresponding VT3 of V Low level is remained on the upper and grid of the corresponding VT5 of W, when VT1 is connected, electric current is flowed into the motor of variable-frequency motor by VT1 Coil, VT3 and VT5 remain shutdown.Described by vector be exactly, on IGBT alternately apply (1,0,0) and (0,0, 0), it is, U phase inputs U phase PWM wave, and V phase is always maintained at shutdown with W phase.It can be with by adjusting the duty ratio of U phase PWM wave First coil electric current is adjusted.

Specifically, first coil electric current can be adjusted in the following manner:

Preset duty ratio increment Delta T；

When first coil electric current is less than the first predetermined current, increase on the basis of the current duty cycle of target phase PWM wave Add Δ T；

When first coil electric current is greater than the first predetermined current, subtract on the basis of the current duty cycle of target phase PWM wave Small Δ T.

The variation tendency of first coil electric current are as follows: it is gradually increased since 0, when reaching near the first predetermined current, First predetermined current nearby fluctuates, until equal with the first predetermined current.

When detecting that first coil electric current is equal to the first predetermined current, the current duty cycle Ta of target phase PWM wave is determined, The duty ratio for keeping target phase PWM wave is that Ta is constant, and control variable-frequency motor runs the first preset duration.

In embodiments of the present invention, to the corresponding target phase PWM wave of IGBT input target, pass through target phase PWM wave control The direction of rotor processed to the target phase of variable-frequency motor is mobile, when first coil electric current is equal to the first predetermined current, reaches frequency conversion The direction of the target phase of motor.

In an embodiment of the present invention, the information of the determination PWM wave, the information of the IGBT and the variable-frequency electric First operation information of machine determines institute according to the information of the PWM wave, the information of the IGBT and first operation information State the phase resistance of variable-frequency motor, comprising:

In embodiments of the present invention, the information of PWM wave includes: the duty in the first preset duration of target phase PWM wave Than the period with target phase PWM wave.The information of IGBT includes: the forward conduction voltage and IGBT of the dead time of IGBT, IGBT The sum of freewheeling diode forward conduction voltage drop.First operation information of variable-frequency motor includes: to terminate the first preset duration The first coil electric current of moment electrical-coil and the bus voltage value of variable-frequency motor.

Wherein it is possible to determine the first coil electricity of electrical-coil at the time of terminating the first preset duration in the following manner Stream: sampling first coil electric current in the first preset duration, calculates average value, using the average value as in end first The first coil electric current of electrical-coil at the time of preset duration.

Similarly, the bus voltage value of variable-frequency motor at the time of terminating the first preset duration can be determined.

In an embodiment of the present invention, this method further comprises: preset the forward conduction voltage of the IGBT with The corresponding relationship of the sum of freewheeling diode forward conduction voltage drop of the IGBT and first predetermined current；

In an embodiment of the present invention, described that the PWM wave is acted on into the IGBT, by controlling the PWM wave Duty ratio, by the rotor fixed position to the direction with α axis at second angle, comprising:

In embodiments of the present invention, pass through duty ratio, the duty ratio of V phase PWM wave and the W phase PWM wave of control U phase PWM wave Duty ratio, to control the second coil current of electrical-coil.

In embodiments of the present invention, after the duty ratio every time to V phase PWM wave is adjusted, V phase adjusted is utilized PWM wave is input to IGBT, after the duty ratio every time to W phase PWM wave is adjusted, is input to using W phase PWM wave adjusted IGBT。

Specifically, the second coil current can be adjusted in the following manner:

Tu [n]=Tc/2, Tv [n]=Tc/2- △ Tu [n], Tw [n]=Tc/2+ △ Tu [n] are set, wherein Tu [n] is The duty ratio of U phase PWM wave when the n-th detection, the duty ratio of V phase PWM wave when Tv [n] is the n-th detection, W when Tw [n] is the n-th detection The duty ratio of phase PWM wave, the initial value of Tu [n], Tv [n] and Tw [n] all can be Tc/2, Tc is the corresponding triangular wave of PWM wave The half of carrier cycle.

When the second coil current is greater than the second predetermined current, △ Tu [n]=△ Tu [n-1]-△ Tu；

When the second coil current is less than the second predetermined current, △ Tu [n]=△ Tu [n-1]+△ Tu；

Wherein, it is constant to be always maintained at Tc/2 for the duty ratio of U phase PWM wave.

In embodiments of the present invention, the duty ratio of U phase PWM wave, the duty ratio of the duty ratio of V phase PWM wave and W phase PWM wave It is identical as the duty ratio corresponding in the second preset duration, in particular to, in the duty ratio of U phase PWM wave and the second preset duration U phase PWM wave duty ratio it is identical, the duty ratio phase of the duty ratio of V phase PWM wave and the V phase PWM wave in the second preset duration Together, the duty ratio of W phase PWM wave is identical as the duty ratio of W phase PWM wave in the second preset duration.

In embodiments of the present invention, control electric current flows into the electrical-coil from the change from the W phase of the variable-frequency motor The V phase of frequency motor flows out, and can be accomplished by the following way:

Vector (0,0,1), (1,0,1), and (0,0,0) and/or (1,1,1) are alternately issued on IGBT.

In an embodiment of the present invention, the duty ratio of the U phase PWM wave, the duty ratio of the V phase PWM wave and the W phase The initial value of the duty ratio of PWM wave is Tc/2, wherein Tc is the half in the PWM wave corresponding triangular wave carrier period.

In an embodiment of the present invention, the second operation information of the determination variable-frequency motor, comprising:

In embodiments of the present invention, electrical-coil at the time of terminating the second preset duration can be determined in the following manner The second coil current: the second coil current is sampled in the second preset duration, calculate average value, which is made For the second coil current of electrical-coil at the time of terminating the second preset duration.

The tertiary coil electric current of electrical-coil at the time of terminating third preset duration can be determined in the following manner: Tertiary coil electric current is sampled in third preset duration, calculates average value, is preset using the average value as in end third The tertiary coil electric current of electrical-coil at the time of duration.

In an embodiment of the present invention, with α axis at the direction of the first angle and with α axis at the side of the second angle To satisfaction: being rotated by 90 ° arrival and α axis counterclockwise into the direction of the first angle at the direction of the second angle with α axis.

In embodiments of the present invention, can refer to the positive axis of α axis at the direction of first angle into first angle with α axis Direction, correspondingly, can refer at the direction of second angle the direction with the positive axis of α axis at second angle with α axis.

For example, first angle is 0 °, then, second angle is 270 °.First angle be 120 ° so, second angle It is 30 °.First angle is 240 °, then, second angle is 150 °.

In an embodiment of the present invention, the U phase of the variable-frequency motor is overlapped with the positive axis of the α axis.

As shown in figure 3, between the fixed coordinate system that the fixed coordinate system that α axis and β axis are constituted is constituted with U phase, V phase, W phase Relationship.In figure, positive axis and the U of α axis coincide.

As shown in figure 4, this method can the embodiment of the invention provides a kind of method of the d axle inductance of determining variable-frequency motor With the following steps are included:

Step 401: in real time to the corresponding U phase PWM wave of U of the IGBT of variable-frequency motor input variable-frequency motor.

Specifically, keeping VT3 and VT5 is the state of shutdown, and electric current flows into electrical-coil by U phase, flowed out by V phase with W phase.

Step 402: real-time detection flows into the first coil electric current of electrical-coil, when detecting first coil electric current less than the When one predetermined current, increase the duty ratio of U phase PWM wave；When detecting that first coil electric current is greater than the first predetermined current, reduce The duty ratio of U phase PWM wave；When detecting that first coil electric current is equal to the first predetermined current, the duty ratio of U phase PWM wave is kept It is constant, the first preset duration is run using U phase PWM wave control variable-frequency motor, rotor reaches and α axis after the first preset duration At 0 ° of direction, the first coil electric current of electrical-coil and the bus of variable-frequency motor at the time of terminating the first preset duration are determined Voltage value.

Step 403: determining the duty ratio in the first preset duration of U phase PWM wave, the period of U phase PWM wave, determine The dead time of IGBT, and, the sum of forward conduction voltage and the freewheeling diode forward conduction voltage drop of IGBT of IGBT.

Step 404: according to formula one, determining the phase resistance of variable-frequency motor, formula one are as follows:

Step 405: control variable-frequency motor electric discharge, it is defeated to IGBT in real time for the U phase of variable-frequency motor after the completion of electric discharge Enter U phase PWM wave, for the V phase of variable-frequency motor, in real time to IGBT input V phase PWM wave, for the W phase of variable-frequency motor, in real time to IGBT inputs W phase PWM wave.

Specifically, it by stopping inputting various PWM waves to IGBT, discharges to realize variable-frequency motor, in variable-frequency motor weight After multiple electric discharge, PWM wave is being inputted to IGBT.

Step 406: duty ratio, the duty ratio of the duty ratio of V phase PWM wave and W phase PWM wave by controlling U phase PWM wave, Control electric current flows into electrical-coil from the W phase of variable-frequency motor and flows out from the V phase of variable-frequency motor.

Step 407: real-time detection flows into the second coil current of the electrical-coil of variable-frequency motor；When detecting the second coil When electric current is greater than the second predetermined current, increase the duty ratio of V phase PWM wave, reduces the duty ratio of W phase PWM wave；When detecting second When coil current is less than the second predetermined current, reduce the duty ratio of V phase PWM wave, increases the duty ratio of W phase PWM wave；When detecting When second coil current is equal to the second predetermined current, duty ratio, the duty ratio of V phase PWM wave and the W phase PWM of U phase PWM wave are kept The duty ratio of wave is constant, using U phase PWM wave, V phase PWM wave and W phase PWM wave, when control variable-frequency motor operation second is default Long, rotor reaches with α axis into 270 ° of direction after the second preset duration, determines electric at the time of terminating the second preset duration Second coil current of machine coil.

Step 408: control variable-frequency motor electric discharge, it is defeated to IGBT in real time for the U phase of variable-frequency motor after the completion of electric discharge Enter U phase PWM wave, for the V phase of variable-frequency motor, in real time to IGBT input V phase PWM wave, for the W phase of variable-frequency motor, in real time to IGBT inputs W phase PWM wave.

Step 409: U phase PWM wave, V phase PWM wave and W phase PWM wave are utilized, control variable-frequency motor runs third preset duration, Rotor reaches with α axis into 270 ° of direction after third preset duration, determines motor at the time of terminating third preset duration The tertiary coil electric current of coil, wherein the duty ratio of the duty ratio of U phase PWM wave, the duty ratio of V phase PWM wave and W phase PWM wave is equal It is identical as the duty ratio corresponding in the second preset duration.

Step 410: according to formula two, determining the d axle inductance of variable-frequency motor, formula two are as follows:

In embodiments of the present invention, by controlling the duty ratio of PWM wave, control is in phase resistance identification in electrical-coil Electric current, and the electric current in the identification of d axle inductance in electrical-coil is controlled, the difference of phase resistance and inductance is avoided, motor is caused When parameter identification, cannot effectively identifying motor parameter and it is existing because identification electric current it is excessive caused by motor demagnetize the problems such as, It is suitble to the general parameter identification of motor.

As shown in figure 5, the embodiment of the invention provides a kind of devices of the d axle inductance of determining variable-frequency motor, comprising:

First control unit 501, for PWM wave to be acted on to the IGBT of variable-frequency motor, by controlling accounting for for the PWM wave Empty ratio, by the rotor fixed position of the variable-frequency motor to the direction with α axis in the fixed coordinates axis at first angle；

Phase resistance determination unit 502, for determining the information, the information of the IGBT and the variable-frequency electric of the PWM wave First operation information of machine determines institute according to the information of the PWM wave, the information of the IGBT and first operation information State the phase resistance of variable-frequency motor；

After the completion of electric discharge, the PWM wave is acted on for controlling the variable-frequency motor electric discharge for second control unit 503 In the IGBT, by controlling the duty ratio of the PWM wave, by the rotor fixed position to the direction with α axis at second angle, really Second operation information of the fixed variable-frequency motor；

After the completion of electric discharge, the PWM wave is acted on for controlling the variable-frequency motor electric discharge for third control unit 504 In the IGBT, by the rotor fixed position to the direction with α axis at the second angle, the third fortune of the variable-frequency motor is determined Row information；

Inductance determination unit 505 is believed for being run according to the phase resistance, second operation information and the third Breath, determines the d axle inductance of the variable-frequency motor.

The first control unit, is used for:

In an embodiment of the present invention, second control unit, it is described executing described for the PWM wave and acting on IGBT, by controlling the duty ratio of the PWM wave, by the rotor fixed position arrive with α axis at second angle direction when, specific use In:

In an embodiment of the present invention, the phase resistance determination unit, is used for:

In an embodiment of the present invention, second control unit is executing the second of the determination variable-frequency motor When operation information, it is specifically used for: determines the second coil electricity of the electrical-coil described at the time of terminating second preset duration Stream；

The third control unit is specifically used for when executing the third operation information of the determination variable-frequency motor: Determine the tertiary coil electric current of the electrical-coil described at the time of terminating the third preset duration；

The inductance determination unit, for determining the d axle inductance of the variable-frequency motor, the formula two according to formula two Are as follows:

In an embodiment of the present invention, which further comprises:

Setting unit, for the forward conduction voltage of the IGBT and the freewheeling diode forward conduction of the IGBT to be arranged The corresponding relationship of the sum of pressure drop and first predetermined current；According to first predetermined current and the corresponding relationship, determine The forward conduction voltage of the IGBT and the sum of the freewheeling diode forward conduction voltage drop of the IGBT.

The each embodiment of the present invention at least has the following beneficial effects:

1, in embodiments of the present invention, PWM wave does not immobilize, and the duty ratio of PWM wave can be according to variable-frequency motor Operating condition adjusts in real time, and the duty ratio by controlling PWM wave can be by the rotor fixed position of variable-frequency motor to the position needed, in fact Now to the accurate positionin of rotor, and then can be according to the operation information of variable-frequency motor, the information of the information of IGBT and PWM wave, more Add the d axle inductance for accurately determining out variable-frequency motor.

2, in embodiments of the present invention, by controlling the duty ratio of PWM wave, control is in phase resistance identification in electrical-coil Electric current, and control the electric current in the identification of d axle inductance in electrical-coil, avoid the difference of phase resistance and inductance, cause electricity When machine parameter identification, cannot effectively identifying motor parameter and it is existing because identification electric current it is excessive caused by motor demagnetization etc. ask Topic is suitble to the general parameter identification of motor.

It should be noted that, in this document, such as first and second etc relational terms are used merely to an entity Or operation is distinguished with another entity or operation, is existed without necessarily requiring or implying between these entities or operation Any actual relationship or order.Moreover, the terms "include", "comprise" or its any other variant be intended to it is non- It is exclusive to include, so that the process, method, article or equipment for including a series of elements not only includes those elements, It but also including other elements that are not explicitly listed, or further include solid by this process, method, article or equipment Some elements.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that including There is also other identical factors in the process, method, article or equipment of the element.

Those of ordinary skill in the art will appreciate that: realize that all or part of the steps of above method embodiment can pass through The relevant hardware of program instruction is completed, and program above-mentioned can store in computer-readable storage medium, the program When being executed, step including the steps of the foregoing method embodiments is executed；And storage medium above-mentioned includes: ROM, RAM, magnetic disk or light In the various media that can store program code such as disk.

Finally, it should be noted that the foregoing is merely presently preferred embodiments of the present invention, it is merely to illustrate skill of the invention Art scheme, is not intended to limit the scope of the present invention.Any modification for being made all within the spirits and principles of the present invention, Equivalent replacement, improvement etc., are included within the scope of protection of the present invention.

Claims

1. a kind of method of the d axle inductance of determining variable-frequency motor characterized by comprising

The insulated gate bipolar transistor IGBT that pulse width modulation (PWM) wave is acted on to variable-frequency motor, by controlling the PWM The duty ratio of wave, by the rotor fixed position of the variable-frequency motor to the direction with α axis in the fixed coordinates axis at first angle；

The first operation information for determining the information of the PWM wave, the information of the IGBT and the variable-frequency motor, according to described The information of PWM wave, the information of the IGBT and first operation information, determine the phase resistance of the variable-frequency motor；

The variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, by described in control The duty ratio of PWM wave determines the second fortune of the variable-frequency motor by the rotor fixed position to the direction with α axis at second angle Row information；

The variable-frequency motor electric discharge is controlled, after the completion of electric discharge, the PWM wave is acted on into the IGBT, the rotor is determined Position, at the direction of the second angle, determines the third operation information of the variable-frequency motor to α axis；

According to the phase resistance, second operation information and the third operation information, the d axis electricity of the variable-frequency motor is determined Sense.

2. the method according to claim 1, wherein

The target of the variable-frequency motor mutually includes: the U phase of the variable-frequency motor, the V phase of the variable-frequency motor and the variable-frequency electric Any one in the W phase of machine；

The IGBT that PWM wave is acted on to variable-frequency motor, by controlling the duty ratio of the PWM wave, by the variable-frequency motor Rotor fixed position to the direction with α axis in the fixed coordinates axis at first angle, comprising:

When detecting the first coil electric current less than the first predetermined current, increase the duty ratio of the target phase PWM wave；

When detecting that the first coil electric current is greater than first predetermined current, reduce the duty of the target phase PWM wave Than；

When detecting that the first coil electric current is equal to first predetermined current, the duty of the target phase PWM wave is kept Than constant, control the variable-frequency motor using the target phase PWM wave and run the first preset duration, by described first it is default when The rotor reaches the direction with α axis at the first angle after length.

3. according to the method described in claim 2, it is characterized in that,

First operation information of the information of the determination PWM wave, the information of the IGBT and the variable-frequency motor, according to institute The information of PWM wave, the information of the IGBT and first operation information are stated, determines the phase resistance of the variable-frequency motor, comprising:

Determine the duty ratio in first preset duration of the target phase PWM wave, the period of the target phase PWM wave；

Determine the dead time of the IGBT, and, the forward conduction voltage of the IGBT and the freewheeling diode of the IGBT The sum of forward conduction voltage drop；

Determine the first coil electric current and the variable-frequency motor of the electrical-coil described at the time of terminating first preset duration Bus voltage value；

Wherein, r is the phase resistance, E_dcFor the busbar voltage of the variable-frequency motor described at the time of terminating first preset duration Value, T_aFor the duty ratio in first preset duration of the target phase PWM wave, T_dFor the dead time of the IGBT, V_s For the forward conduction voltage of the IGBT, V_dFor the freewheeling diode forward conduction voltage drop of the IGBT, T is the target phase The period of PWM wave, I₀For the first coil electric current of the electrical-coil described at the time of terminating first preset duration.

4. method according to claim 1 to 3, which is characterized in that

It is described that the PWM wave is acted on into the IGBT, by controlling the duty ratio of the PWM wave, the rotor fixed position is arrived With α axis at the direction of second angle, comprising:

For the U phase of the variable-frequency motor, U phase PWM wave is inputted to the IGBT in real time, it is real for the V phase of the variable-frequency motor When to the IGBT input V phase PWM wave, for the W phase of the variable-frequency motor, in real time to the IGBT input W phase PWM wave；

By controlling duty ratio, the duty ratio of the duty ratio of the V phase PWM wave and the W phase PWM wave of the U phase PWM wave, Control electric current flows into the electrical-coil from the W phase of the variable-frequency motor and flows out from the V phase of the variable-frequency motor；

When detecting that second coil current is greater than the second predetermined current, increase the duty ratio of the V phase PWM wave, reduces The duty ratio of the W phase PWM wave；

When detecting that second coil current is less than second predetermined current, reduce the duty ratio of the V phase PWM wave, Increase the duty ratio of the W phase PWM wave；

When detect second coil current be equal to second predetermined current when, keep the U phase PWM wave duty ratio, The duty ratio of the duty ratio of the V phase PWM wave and the W phase PWM wave is constant, utilizes the U phase PWM wave, the V phase PWM Wave and the W phase PWM wave control the variable-frequency motor and run the second preset duration, described after second preset duration Rotor reaches the direction with α axis at the second angle；

It is described that the PWM wave is acted on into the IGBT, by the rotor fixed position to the direction with α axis at the second angle, Include:

Using the U phase PWM wave, the V phase PWM wave and the W phase PWM wave, it is default to control the variable-frequency motor operation third Duration, the rotor reaches the direction with α axis at the second angle after the third preset duration, wherein the U phase The duty ratio of the duty ratio of PWM wave, the duty ratio of the V phase PWM wave and the W phase PWM wave with second preset duration Interior duty ratio corresponding is identical.

5. according to the method described in claim 4, it is characterized in that,

It is described according to the phase resistance, second operation information and the third operation information, determine the d of the variable-frequency motor Axle inductance, comprising:

Wherein, L_dFor the d axle inductance of the variable-frequency motor, r is the phase resistance, and t is the third preset duration, I_w0To tie Second coil current of the electrical-coil, I at the time of the second preset duration of Shu Suoshu_w1To terminate the third preset duration At the time of the electrical-coil tertiary coil electric current.

6. according to the method described in claim 3, it is characterized in that,

Further comprise: presetting the forward conduction voltage of the IGBT and the freewheeling diode forward conduction pressure of the IGBT Corresponding relationship of the sum of the drop with first predetermined current；

According to first predetermined current and the corresponding relationship, determine the forward conduction voltage of the IGBT with the IGBT's The sum of freewheeling diode forward conduction voltage drop.

7. according to the method described in claim 4, it is characterized in that,

The initial value of the duty ratio of the duty ratio of the U phase PWM wave, the duty ratio of the V phase PWM wave and the W phase PWM wave is equal For Tc/2, wherein Tc is the half in the PWM wave corresponding triangular wave carrier period.

8. any method in -7 according to claim 1, which is characterized in that

Meet at the direction of the first angle and with α axis at the direction of the second angle with α axis: with α axis at described second The direction of angle is rotated by 90 ° arrival and α axis into the direction of the first angle counterclockwise；

And/or

9. a kind of device of the d axle inductance of determining variable-frequency motor characterized by comprising

First control unit, for pulse width modulation (PWM) wave to be acted on to the insulated gate bipolar transistor of variable-frequency motor IGBT, by controlling the duty ratio of the PWM wave, by the rotor fixed position of the variable-frequency motor to α in the fixed coordinates axis Axis at first angle direction；

Phase resistance determination unit, for determining the first of the information of the PWM wave, the information of the IGBT and the variable-frequency motor Operation information determines the variable-frequency electric according to the information of the PWM wave, the information of the IGBT and first operation information The phase resistance of machine；

Second control unit after the completion of electric discharge, the PWM wave is acted on described for controlling the variable-frequency motor electric discharge The rotor fixed position is arrived the direction with α axis at second angle by controlling the duty ratio of the PWM wave by IGBT, described in determination Second operation information of variable-frequency motor；

Third control unit after the completion of electric discharge, the PWM wave is acted on described for controlling the variable-frequency motor electric discharge IGBT determines the third operation letter of the variable-frequency motor by the rotor fixed position to the direction with α axis at the second angle Breath；

Inductance determination unit, for determining institute according to the phase resistance, second operation information and the third operation information State the d axle inductance of variable-frequency motor.

10. device according to claim 9, which is characterized in that

The first control unit, is used for:

When detecting that the first coil electric current is equal to first predetermined current, the duty of the target phase PWM wave is kept Than constant, control the variable-frequency motor using the target phase PWM wave and run the first preset duration, by described first it is default when The rotor reaches the direction with α axis at the first angle after length；

And/or

Second control unit, execute it is described the PWM wave is acted on into the IGBT, pass through the control PWM wave Duty ratio, by the rotor fixed position to α axis at second angle direction when, be specifically used for:

The third control unit, execute it is described the PWM wave is acted on into the IGBT, the rotor fixed position is arrived and α Axis at the second angle direction when, be specifically used for:

Using the U phase PWM wave, the V phase PWM wave and the W phase PWM wave, it is default to control the variable-frequency motor operation third Duration, the rotor reaches the direction with α axis at the second angle after the third preset duration, wherein the U phase The duty ratio of the duty ratio of PWM wave, the duty ratio of the V phase PWM wave and the W phase PWM wave with second preset duration Interior duty ratio corresponding is identical；

And/or