GB/T 5171.22-2017Small-power motors—Part 22:Test methods for permanent magnet brushless DC motors (English PDF)

6.1 Overview

The purpose of the temperature rise test is to determine the temperature rise of the windings and certain parts of the motor, when the motor is running under specified load conditions when the temperature is higher than that of the cooling medium. The temperature measurement method shall be selected, according to 4.3 and the relevant provisions of this Chapter.

For the motor with an external controller and no dedicated controller, the temperature rise of the motor is measured, using a test frequency converter for power supply.

6.2 General descriptions

General descriptions shall comply with the provisions of 6.2 in GB/T 5171.21-2016.

6.3 Determination of the cooling medium temperature at the end of temperature rise test

The determination of the temperature of the cooling medium, at the end of the temperature rise test, shall comply with the provisions in 6.3 of GB/T 5171.21-2016.

6.4 Measurement method of temperature of motor winding and other parts

The measurement method of the temperature of the motor winding and other parts shall comply with the provisions in 6.4 of GB/T 5171.21-2016.

6.5 Temperature rise test method

The temperature rise test method shall comply with the provisions in 6.5 of GB/T 5171.21-2016.

6.6 Calculation of winding operating temperature theta 2

The calculation of the winding operating temperature theta 2 shall comply with the provisions of 6.6 in GB/T 5171.21-2016.

6.7 Calculation of winding temperature rise deltatheta

The calculation of winding temperature rise deltatheta shall comply with the provisions of 6.7 in GB/T 5171.21-2016.

8.2 Short-term over-torque test

The short-term over-torque test shall comply with the provisions in 9.2 of GB/T 5171.21-2016.

8.3 Determination of maximum torque

The determination of the maximum torque shall comply with the provisions in 9.3 of GB/T 5171.21-2016.

8.4 Determination of minimum torque

The determination of the minimum torque shall comply with the provisions in 9.4 of GB/T 5171.21-2016.

8.5 Determination of moment of inertia

The determination of the moment of inertia shall comply with the provisions in 9.5 of GB/T 5171.21-2016.

8.6 Magnetic stability inspection of permanent magnet motors

The magnetic stability inspection of permanent magnet motors shall comply with the provisions in 9.6 of GB/T 5171.21-2016.

8.7 Determination of noise

The determination of motor noise shall be carried out according to the provisions of GB/T10069.1.

8.8 Measurement of vibration

The determination of motor vibration shall be carried out according to the provisions of JB/T 10490.

8.9 Electric strength test

The electric strength test of the motor shall comply with the provisions in 9.9 of GB/T 5171.21-2016.

8.10 Repeated electric strength test

The repeated electric strength test shall comply with the provisions in 9.10 of GB/T 5171.21-2016.

8.11 Electric strength test of inter-turn insulation

The inter-turn insulation test of the motor winding shall be carried out, to assess the ability of the inter-turn insulation of the winding to withstand overvoltage. The test shall adopt the inter-turn impulse electric strength test method; it shall not use the short-time rising voltage test method.

Impulse voltage waves, which have specified peak value and wave front time, are directly applied to the winding of the tested product or the reference product of the same design alternately (or simultaneously). Whether there is any difference in the attenuation oscillation waveform, which is caused by the impulse voltage between the two, is used to detect whether the inter-turn insulation of the motor winding is good.

For motors, which have a DC voltage UDC above 48 V, the peak value of the impulse voltage wave is calculated according to formula (1); the minimum is 2100 V; the wave front time is 0.2 µs.

For motors, which have a DC voltage UDC of 48 V and below, the peak value of the impulse voltage wave is 800 V; the wave front time is 0.2 µs.

The specific test method for the inter-turn impact electric strength test of the winding is carried out, according to GB/T 22719.1.

Note: The electric strength test of the inter-turn insulation of permanent magnet brushless DC motor windings shall be carried out on the motor windings, during the motor manufacturing process.

8.12 Leakage current test at operating temperature

The leakage current test at the operating temperature of the motor shall comply with the provisions in 9.12 of GB/T 5171.21-2016.

8.13 Accidental overcurrent test

The accidental overcurrent test of the motor shall comply with the provisions in 9.13 of GB/T 5171.21-2016.

8.14 Overspeed test

The motor overspeed test shall comply with the provisions of 9.14 in GB/T 5171.21-2016.

8.15 Test of protection level

The motor protection level test shall comply with the provisions of 9.15 in GB/T 5171.21-2016.

8.16 Damp heat test

the system can be tested by an external simulation device or other methods.

A.1 Requirements for overcurrent protection

The setting value of the overcurrent protection device is determined by the manufacturer, according to the actual application of the motor. When the motor current is too large, the overcurrent protection device shall be able to operate, according to the instructions.

A.2 Slow overload test

The test steps are as follows:

1) Supply power at rated voltage; start the motor, to make it run under rated load until thermally stable; keep the load constant;

2) Measure the winding current of the motor; record it;

3) Increase the load, so that the winding current increases by 10%; let the motor work again, until the heat stabilizes. At this time, keep the power supply voltage constant;

4) Increase the load again, to repeat the above test, until the overcurrent protection device operates or the motor stops;

5) After each overcurrent protection device operates, measure and record the temperature of the motor winding;

6) Record the change of the current value during the test; take records according to Table A.1;

7) Observe whether the overcurrent protection device operates, when the current value exceeds the set value;

8) Repeat the above test, to make the overcurrent protection device operate several times;

9) Observe the action of the motor protective device, until the motor winding temperature exceeds the maximum winding temperature specified in the product manual.

B.1 Judgment of overvoltage and undervoltage

The motor has a protective function against the hazards of overvoltage and undervoltage, within the deviation (±15%) of the rated input voltage. After the motor is connected to the controller, it shall be able to act according to the product manual, to protect the motor in the case of overvoltage or undervoltage.

B.2 Overvoltage protection test

B.2.1 Test procedure

The test procedure are as follows:

1) Start the motor, to make it run to thermal stability under rated load; keep the load constant;

2) Measure the input voltage value Uin of the motor controller terminal of the controller; record it;

3) Start timing; record the time t; increase Uin gradually, until Uin reaches the specified value Uover; observe the motor protection action.

B.2.2 Judgment

The motor shall be able to perform protection actions, according to the requirements of the product manual.

B.3 Undervoltage protection test

B.3.1 Test procedure

The test steps are as follows:

1) Start the motor, to make it run to thermal stability under rated load; keep the load constant;

2) Measure and record the input voltage value Uin at the motor controller end of the controller;

3) Start timing; record the time t; gradually reduce Uin, until Uin reaches the specified […]