CN105116331A - Test method for motor under high-temperature and high-pressure environment - Google Patents

Abstract

The invention relates to a test method for a motor under a high-temperature and high-pressure environment and belongs to the technical field of motor characteristic testing under the high-temperature and high-pressure environment. The test method includes the following steps that: a measured motor and an accompanying motor are arranged in a high-pressure and high-temperature sealed barrel; the measured motor works in a motor state, and the accompanying motor works in a generator state; the stator current of the measured motor is gradually decreased to 0.5-times rated current from 1.5-times rated current; the stray loss of the measured motor working in the motor state is P<Ms>; the measured motor works in a generator state, and the accompanying motor works in a motor state; the stator current of the accompanying motor is gradually decreased to 0.5-times rated current from 1.5-times rated current; the stray loss of the measured motor working in the generator state is P<Gs>; the average value P<->s of the stray loss of the load of the measured motor can be obtained based on the above measured parameters and calculation results. With the test method of the invention adopted, the parameters of the motor can be detected under the high-temperature and high-pressure environment. According to the test method, required parameters are measured through utilizing a motor which has the same specification as the measured motor.

Description

The method of testing of motor under a kind of high temperature and high pressure environment

Technical field

The invention belongs to the technical field of motor characteristic test under high temperature and high pressure environment.

Background technology

Along with the mankind constantly increase the demand of resource and the energy, as the motor of requisite execution and functional part in exploration and exploitation, can more and more be applied in various extreme environment, such as high temperature and high pressure environment, and motor is before practical application, must test accordingly its performance, to verify that can it reach application requirement, also should provide the performance parameter of some necessity simultaneously.But the method for testing of existing motor is applicable in normal temperature and pressure situation more, the environment of environment or High Temperature High Pressure that its some testing apparatuss used can not be operated in High Temperature High Pressure can have a strong impact on its measuring accuracy.

Summary of the invention

The object of this invention is to provide the method for testing of motor under a kind of high temperature and high pressure environment, is that the method for testing in order to solve existing motor is applicable to normal temperature and pressure situation more, can not meet the problem of the test of motor in High Temperature High Pressure situation.

Described object is realized by following scheme: the method for testing of motor under described a kind of high temperature and high pressure environment, and its method step is:

Step one: select one identical with by measured motor 1 specification, or with by measured motor 1, there is identical synchronous rotational speed but power is greater than by the motor of other specification of measured motor 1 as accompanying and serving motor 2; Be in transmission connection by the output revolving shaft of measured motor 1 by shaft coupling 3 and the output revolving shaft of accompanying and serving motor 2, then high pressure-temperature sealing bucket 4 internal fixtion is put into good, be wound around heating cables in the outside of high pressure-temperature sealing bucket 4 or withstand voltage large power, electrically well heater is set in the inside of high pressure-temperature sealing bucket 4, and the insulation material of insulated fireproof is superscribed in outside, high pressure-temperature is sealed bucket 4 inside and be full of experiment oil, the probe temperature sealed by high pressure-temperature in bucket 4 arranges between 100 DEG C ~ 200 DEG C, and oil pressure force value experimentally needs the setting carrying out being correlated with;

Step 2: make to be operated in electric motor state by measured motor 1, accompany and serve motor 2 and be operated in Generator Status; First driver 5 drives by measured motor 1 operation, makes to be worked under rated frequency and rated voltage by measured motor 1; Second driver 6 driving is accompanied and served motor 2 and is worked, and makes to accompany and serve motor 2 relative to being turned to upper applying reverse drive by measured motor 1; The second driver 6 is regulated to make in nominal load situation, to be run to steady state (SS) by measured motor 1;

Step 3: by second driver 6 regulate accompany and serve motor 2, make to be changed to 0.5 times of rated current by the stator current of measured motor 1 gradually from 1.5 times of rated current, read in this course as motor running by the triple-phase line electric current I of measured motor 1 _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor 1; Read work is in the triple-phase line electric current I of accompanying and serving motor 2 of Generator Status simultaneously _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor 1 and the stator copper loss of accompanying and serving motor 2 in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 4: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _mand s _g, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _m, N _g, and with stopwatch record N _m, N _gthe time t of secondary swing _m, t _g; Then following formula is used to determine by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _mand s _g:

$\begin{array}{cc}{s}_M=\frac{N_M}{2t_M{f}_M}\&times;100\%;& s_G=\frac{N_G}{2t_G{f}_G}\&times;100\%,\end{array}$

In formula, f _mfor by the rated frequency of measured motor 1; f _gfor accompanying and serving the frequency of motor 2, this frequency is less than rated frequency;

Step 5: be operated in electric motor state by the rotor copper loss P of measured motor 1 _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P _fe); Be operated in the rotor copper loss P accompanying and serving motor 2 of Generator Status _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P` _fe);

Step 6: be operated under electric motor state by the stray loss P of measured motor 1 _ms: P _ms=∑ P _sp _mcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor 1 and total stray loss of accompanying and serving motor 2, and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 7: and motor 2 will be accompanied and served to shut down work by measured motor 1; Make to be operated in Generator Status by measured motor 1, accompany and serve motor 2 and be operated in electric motor state; Second driver 6 drives and accompanies and serves motor 2 operation, makes to accompany and serve motor 2 and works under rated voltage He under being greater than rated frequency condition; First driver 5 drives and is worked by measured motor 1, makes to be turned to upper applying reverse drive by measured motor 1 relative to accompanying and serving motor 2; The load value regulating the first driver 5 to make to accompany and serve motor 2 be worth equal situation by measured motor 1 nominal load under run to steady state (SS);

Step 8: regulated by measured motor 1 by the first driver 5, is made the stator current of accompanying and serving motor 2 change to 0.5 times of rated current gradually from 1.5 times of rated current, reads the triple-phase line electric current I of accompanying and serving motor 2 as motor running in this course _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor 1; Simultaneously read work at Generator Status by the triple-phase line electric current I of measured motor 1 _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor 1 and the stator copper loss of accompanying and serving motor 2 in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 9: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _gand s _m, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _g, N _m, and with stopwatch record N _g, N _mthe time t of secondary swing _g, t _m; Then following formula is used to determine by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _gand s _m:

$\begin{array}{cc}{s}_G=\frac{N_G}{2t_G{f}_G}\&times;100\%;& s_M=\frac{N_M}{2t_M{f}_M}\&times;100\%,\end{array}$

In formula, f _gfor by the rated frequency of measured motor 1; f _mfor accompanying and serving the frequency of motor 2, this frequency is greater than by the rated frequency of measured motor 1;

Step 10: the rotor copper loss P accompanying and serving motor 2 being operated in electric motor state _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P` _fe); Be operated in Generator Status by the rotor copper loss P of measured motor 1 _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P _fe);

Step 11: be operated under Generator Status by the stray loss P of measured motor 1 _gsfor: P _gs=∑ P _sp _gcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor 1 and total stray loss of accompanying and serving motor 2, but now P _gcu2for by measured motor 1 rotor copper loss, P _mcu2for accompanying and serving motor 2 rotor copper loss, and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 12: ask for by the mean value of measured motor 1 load stray loss in conjunction with the measurement parameter in above-mentioned steps and calculating knot for: by the approximate average of measured motor 1 at motor and Generator Status rotor electric current for: in formula, I ₁for during load test by the stator current of measured motor 1 in above-mentioned steps, namely by the stator current of measured motor 1 under electric motor state and Generator Status, I ₀for during by measured motor 1 no-load test, the stator current that rated voltage is corresponding.

The present invention can carry out parameter testing to motor under high temperature and high pressure environment, high temperature and high pressure acts on motor simultaneously, distribute relatively uniform, structure is simple, utilize one with measured by the motor of measured motor same size needed for parameter, doing so avoids under normal circumstances, some electric machine testing device is unsuitable for the shortcoming of this extreme environment of High Temperature High Pressure.

Accompanying drawing explanation

Fig. 1 is the structural representation of the device that the inventive method relates to.

Embodiment

Embodiment one: shown in composition graphs 1, illustrates the technical scheme of this embodiment, and its method step is:

Step one: select one identical with by measured motor 1 specification, or with by measured motor 1, there is identical synchronous rotational speed but power is greater than by the motor of other specification of measured motor 1 as accompanying and serving motor 2; Be in transmission connection by the output revolving shaft of measured motor 1 by shaft coupling 3 and the output revolving shaft of accompanying and serving motor 2, then high pressure-temperature sealing bucket 4 internal fixtion is put into good, be wound around heating cables in the outside of high pressure-temperature sealing bucket 4 or withstand voltage large power, electrically well heater is set in the inside of high pressure-temperature sealing bucket 4, and the insulation material of insulated fireproof is superscribed in outside, high pressure-temperature is sealed bucket 4 inside and be full of experiment oil, the probe temperature sealed by high pressure-temperature in bucket 4 arranges between 100 DEG C ~ 200 DEG C, and oil pressure force value experimentally needs the setting carrying out being correlated with;

Step 2: make to be operated in electric motor state by measured motor 1, accompany and serve motor 2 and be operated in Generator Status; First driver 5 drives by measured motor 1 operation, makes to be worked under rated frequency and rated voltage by measured motor 1; Second driver 6 driving is accompanied and served motor 2 and is worked, and makes to accompany and serve motor 2 relative to being turned to upper applying reverse drive by measured motor 1; The second driver 6 is regulated to make in nominal load situation, to be run to steady state (SS) by measured motor 1;

Step 3: by second driver 6 regulate accompany and serve motor 2, make to be changed to 0.5 times of rated current by the stator current of measured motor 1 gradually from 1.5 times of rated current, read in this course as motor running by the triple-phase line electric current I of measured motor 1 _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor 1; Read work is in the triple-phase line electric current I of accompanying and serving motor 2 of Generator Status simultaneously _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor 1 and the stator copper loss of accompanying and serving motor 2 in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 4: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _mand s _g, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _m, N _g, and with stopwatch record N _m, N _gthe time t of secondary swing _m, t _g; Then following formula is used to determine by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _mand s _g:

$\begin{array}{cc}{s}_M=\frac{N_M}{2t_M{f}_M}\&times;100\%;& s_G=\frac{N_G}{2t_G{f}_G}\&times;100\%,\end{array}$

In formula, f _mfor by the rated frequency of measured motor 1; f _gfor accompanying and serving the frequency of motor 2, this frequency is less than rated frequency;

Step 5: be operated in electric motor state by the rotor copper loss P of measured motor 1 _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P _fe); Be operated in the rotor copper loss P accompanying and serving motor 2 of Generator Status _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P` _fe);

Step 6: be operated under electric motor state by the stray loss P of measured motor 1 _ms: P _ms=∑ P _sp _mcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor 1 and total stray loss of accompanying and serving motor 2, and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 7: and motor 2 will be accompanied and served to shut down work by measured motor 1; Make to be operated in Generator Status by measured motor 1, accompany and serve motor 2 and be operated in electric motor state; Second driver 6 drives and accompanies and serves motor 2 operation, makes to accompany and serve motor 2 and works under rated voltage He under being greater than rated frequency condition; First driver 5 drives and is worked by measured motor 1, makes to be turned to upper applying reverse drive by measured motor 1 relative to accompanying and serving motor 2; The load value regulating the first driver 5 to make to accompany and serve motor 2 be worth equal situation by measured motor 1 nominal load under run to steady state (SS);

Step 8: regulated by measured motor 1 by the first driver 5, is made the stator current of accompanying and serving motor 2 change to 0.5 times of rated current gradually from 1.5 times of rated current, reads the triple-phase line electric current I of accompanying and serving motor 2 as motor running in this course _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor 1; Simultaneously read work at Generator Status by the triple-phase line electric current I of measured motor 1 _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor 1 and the stator copper loss of accompanying and serving motor 2 in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 9: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _gand s _m, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _g, N _m, and with stopwatch record N _g, N _mthe time t of secondary swing _g, t _m; Then following formula is used to determine by measured motor 1 and the revolutional slip s accompanying and serving motor 2 _gand s _m:

$\begin{array}{cc}{s}_G=\frac{N_G}{2t_G{f}_G}\&times;100\%;& s_M=\frac{N_M}{2t_M{f}_M}\&times;100\%,\end{array}$

In formula, f _gfor by the rated frequency of measured motor 1; f _mfor accompanying and serving the frequency of motor 2, this frequency is greater than by the rated frequency of measured motor 1;

Step 10: the rotor copper loss P accompanying and serving motor 2 being operated in electric motor state _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P` _fe); Be operated in Generator Status by the rotor copper loss P of measured motor 1 _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P _fe);

Step 11: be operated under Generator Status by the stray loss P of measured motor 1 _gsfor: P _gs=∑ P _sp _gcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor 1 and total stray loss of accompanying and serving motor 2, but now P _gcu2for by measured motor 1 rotor copper loss, P _mcu2for accompanying and serving motor 2 rotor copper loss, and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 12: ask for by the mean value of measured motor 1 load stray loss in conjunction with the measurement parameter in above-mentioned steps and calculating knot for: by the approximate average of measured motor 1 at motor and Generator Status rotor electric current for: in formula, I ₁for during load test by the stator current of measured motor 1 in above-mentioned steps, namely by the stator current of measured motor 1 under electric motor state and Generator Status, I ₀for during by measured motor 1 no-load test, the stator current that rated voltage is corresponding.

Principle of work: the hyperbaric environment needed for experiment, high pressure sealing bucket is mainly utilized to realize, its inside is full of experiment oil, then put into by measured motor, accompany the examination motor (motor identical with the tested rating of electric machine, or with by measured motor, there is identical synchronous rotational speed, power is greater than by the motor of other specifications of measured motor) and the equipment of other test prototype performances, then a flexible pipe is used to be connected with high pressure sealing bucket, the other end of flexible pipe is connected with forcing pump, by forcing pump to oiling in high pressure bucket, just can control the pressure in high pressure bucket, its force value reads by the tensimeter be connected with forcing pump, but in view of manometric precision is not very high, pressure transducer can be put into high pressure bucket, in order to measure the force value of high pressure bucket inside.

Hot conditions needed for experiment is by realizing heating cables uniform winding in high pressure bucket outside, then the other end of heating cables is connected in frequency and the controlled AC power of amplitude, by controlling the frequency and the amplitude that flow into heating cables electric current, control the temperature of high pressure bucket inside, and the temperature of high pressure bucket inside is by putting into the temperature sensor measurement of high pressure bucket.In order to make the temperature stabilization of high pressure bucket inside, need wrap up with the heating cables of fire-resistant insulation material by high pressure bucket outside.

Another method realizing high temperature test condition is that withstand voltage large power, electrically well heater directly to be put into high pressure bucket inner, directly heating experiment oil, in order to accelerate the temperature reached needed for test, also can put into several electric heater in high pressure bucket simultaneously.The lead-in wire of electric heater is directly drawn by the sealing wire hole of high pressure bucket end cap, and be directly connected in frequency and the adjustable AC power of amplitude, the temperature of high pressure bucket inside can be controlled by the output controlling AC power, and utilize the temperature putting into the temperature sensor Real-Time Monitoring high pressure bucket inside of high pressure bucket inside.Also for ease of and ensure that high pressure bucket within reaches required equilibrium temperature, insulation material that still need be fire-resistant in high pressure bucket outer wrap.First and examination motor will be accompanied to put into high pressure bucket internal fixtion respectively good by measured motor, and then get out test environment according to the implementation method of above-mentioned High Temperature High Pressure, just can carry out the dependence test of motor characteristic.

Now measure the no-load characteristic of motor, under being allowed to condition at rated voltage and rated frequency respectively, no-load running is stablized to mechanical loss, then by regulating the voltage be applied on stator winding, carries out the no-load test of motor.No-load test is mainly determined by measured motor and core loss and the mechanical loss of accompanying examination motor.P is counted by the core loss of measured motor and mechanical loss _feand P _Δ, accompany the core loss of examination motor and mechanical loss to count and P` _Δ, owing to being operated in the motor of high-temperature high-pressure state, the resistance of its stator winding can be subject to the joint effect of temperature and pressure, therefore must read at every turn survey parameter while read this value.

The load test of motor forms primarily of two processes, needs to calibrate measurement instrument used, in order to avoid affect measurement result before doing experiment.

Claims (1)

1. the method for testing of motor under high temperature and high pressure environment, is characterized in that its method step is:

Step one: select one identical with by measured motor (1) specification, or with by measured motor (1), there is identical synchronous rotational speed but power is greater than by the motor of other specification of measured motor (1) as accompanying and serving motor (2), be in transmission connection by the output revolving shaft of measured motor (1) by shaft coupling (3) and the output revolving shaft of accompanying and serving motor (2), then high pressure-temperature sealing bucket (4) internal fixtion is put into good, be wound around heating cables in the outside of high pressure-temperature sealing bucket (4) or withstand voltage large power, electrically well heater is set in the inside of high pressure-temperature sealing bucket (4), and the insulation material of insulated fireproof is superscribed in outside, high pressure-temperature is sealed bucket (4) inside and be full of experiment oil, the probe temperature sealed by high pressure-temperature in bucket (4) arranges between 100 DEG C ~ 200 DEG C, oil pressure force value experimentally needs the setting carrying out being correlated with,

Step 2: make to be operated in electric motor state by measured motor (1), accompany and serve motor (2) and be operated in Generator Status; First driver (5) drives by measured motor (1) operation, makes to be worked under rated frequency and rated voltage by measured motor (1); Second driver (6) drives accompanies and serves motor (2) work, makes to accompany and serve motor (2) and turns to upper applying reverse drive relative to by measured motor (1); The second driver (6) is regulated to make in nominal load situation, to be run to steady state (SS) by measured motor (1);

Step 3: regulated by the second driver (6) and accompany and serve motor (2), make to be changed to 0.5 times of rated current by the stator current of measured motor (1) gradually from 1.5 times of rated current, read in this course as motor running by the triple-phase line electric current I of measured motor (1) _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor (1); Read work is in the triple-phase line electric current I of accompanying and serving motor (2) of Generator Status simultaneously _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor (1) and the stator copper loss of accompanying and serving motor (2) in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 4: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor (1) and the revolutional slip s accompanying and serving motor (2) _mand s _g, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _m, N _g, and with stopwatch record N _m, N _gthe time t of secondary swing _m, t _g; Then following formula is used to determine by measured motor (1) and the revolutional slip s accompanying and serving motor (2) _mand s _g:

$\begin{array}{cc}{s}_M=\frac{N_M}{2t_M{f}_M}\&times;100\%;& s_G=\frac{N_G}{2t_G{f}_G}\&times;100\%,\end{array}$

In formula, f _mfor by the rated frequency of measured motor (1); f _gfor accompanying and serving the frequency of motor (2), this frequency is less than rated frequency;

Step 5: be operated in electric motor state by the rotor copper loss P of measured motor (1) _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P _fe); Be operated in the rotor copper loss P accompanying and serving motor (2) of Generator Status _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P` _fe);

Step 6: be operated under electric motor state by the stray loss P of measured motor (1) _ms: P _ms=∑ P _sp _mcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor (1) and total stray loss of accompanying and serving motor (2), and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 7: and motor (2) will be accompanied and served to shut down work by measured motor (1): make to be operated in Generator Status by measured motor (1), accompany and serve motor (2) and be operated in electric motor state; Second driver (6) drives and accompanies and serves motor (2) operation, makes to accompany and serve motor (2) and works under rated voltage He under being greater than rated frequency condition; First driver (5) drives by measured motor (1) work, makes to be turned to upper applying reverse drive by measured motor (1) relative to accompanying and serving motor (2); The load value regulating the first driver (5) to make to accompany and serve motor (2) be worth equal situation by measured motor (1) nominal load under run to steady state (SS);

Step 8: regulated by measured motor (1) by the first driver (5), make the stator current of accompanying and serving motor (2) change to 0.5 times of rated current gradually from 1.5 times of rated current, read the triple-phase line electric current I of accompanying and serving motor (2) as motor running in this course _m1, power input P _m1, stator winding resistance value R _m1, need in process of the test to keep being always ratings by the frequency and voltage of measured motor (1); Simultaneously read work at Generator Status by the triple-phase line electric current I of measured motor (1) _g1, output power P _g2, stator winding resistance value R _g1; The experimental data utilizing above-mentioned measurement to obtain also just can calculate by measured motor (1) and the stator copper loss of accompanying and serving motor (2) in conjunction with following formula:

$\begin{array}{cc}{P}_{Mcu1}=1.5I_{M1}{R}_{M1}^2;& P_{Gcu1}=1.5I_{G1}{R}_{G1}^2;\end{array}$

Step 9: the method measuring rotor one phase current with tong-type ammeter is determined by measured motor) 1) and accompany and serve the revolutional slip s of motor (2) _gand s _m, adopt the method mainly to consider that motor measurement environment constrains other in order to determine the use of the experimental facilities of motor slip ratio; First the number of oscillations N of record current list index _g, N _m, and with stopwatch record N _g, N _mthe time t of secondary swing _g, t _m; Then following formula is used to determine by measured motor (1) and the revolutional slip s accompanying and serving motor (2) _gand s _m:

$s_G=\frac{N_G}{2t_G{f}_G}\&times;100\%;s_M=\frac{N_M}{2t_M{f}_M}\&times;100\%,$

In formula, f _gfor by the rated frequency of measured motor (1); f _mfor accompanying and serving the frequency of motor (2), this frequency is greater than by the rated frequency of measured motor (1);

Step 10: the rotor copper loss P accompanying and serving motor (2) being operated in electric motor state _mcu2: P _mcu2=s _m(P _m1-P _mcu1-P` _fe); Be operated in Generator Status by the rotor copper loss P of measured motor (1) _gcu2: P _gcu2=s _g(P _g2-P _gcu1-P _fe);

Step 11: be operated under Generator Status by the stray loss P of measured motor (1) _gsfor: P _gs=∑ P _sp _gcu2/ (P _gcu2+ P _mcu2), in formula, ∑ P _sfor by measured motor (1) and total stray loss of accompanying and serving motor (2), but now P _gcu2for by measured motor (1) rotor copper loss, P _mcu2for accompanying and serving motor (2) rotor copper loss, and ∑ P _scomputing formula be:

∑P _s＝P _M1-P _G2-P _Mcu1-P _Gcu1-P _Mcu2-P _Gcu2-P _fe-P` <sub>fe</sub>-P <sub>Δ</sub>-P` _Δ；

Step 12: ask for by the mean value of measured motor (1) load stray loss in conjunction with the measurement parameter in above-mentioned steps and calculating knot for: by the approximate average of measured motor (1) at motor and Generator Status rotor electric current for: in formula, I ₁for during load test by measured motor (1) stator current in above-mentioned steps, namely by measured motor (1) stator current under electric motor state and Generator Status, I ₀for during by measured motor (1) no-load test, the stator current that rated voltage is corresponding.