Power reliability test

4002022-08-18
01 Repeated short circuit test 

Test description: Short-circuit the output of the module under various input and output states, the module should be able to achieve protection or retraction, and short-circuit repeatedly for many times. After the fault is eliminated, the module should automatically resume normal operation.

testing method:

  1. No-load to short-circuit: Within the full range of the input voltage, the module should be able to achieve output current limiting or retraction from no-load to short-circuit. After the short-circuit is eliminated, the module should be able to resume normal operation. Let the module repeatedly work from no-load to short-circuit, the short-circuit time is 1s, the release time is 1s, and the duration is 2 hours. After that, release the short circuit to judge whether the module can work normally;
  2. Full load to short circuit: Within the full range of the input voltage, the module should be able to achieve output current limiting or retraction from full load to short circuit. After the short circuit is removed, the module should be able to resume normal operation. Let the module go from full load to short circuit and then keep short circuit for 2 hours. Then release the short circuit to judge whether the module can work normally;
  3. Short-circuit startup: short-circuit the output of the module first, then power on the power supply, and then power on within the input voltage range of the module. The module should be able to achieve normal current limiting or retraction. After the short-circuit fault is eliminated, the module should be able to Return to normal work, repeat the above test 10 times, release the short circuit, and judge whether the module can work normally.

judgement standard:

After the above test, the power module can work normally when it is turned on; the case is checked, and the circuit board and other parts have no abnormality (such as whether the input relay is stuck during the short circuit process), and it is qualified; otherwise, it is unqualified.

02 Repeated switch test

 

Test description: When the output of the power module is under the maximum load, the input voltage is 220v, (input overvoltage point -5v) and (input undervoltage point +5v), the input is repeatedly switched on and off, and the test power module is repeatedly switched on and off. performance.

testing method:

  1. The input voltage is 220v, the power module is fast with the maximum load, use the contactor to control the voltage input, close for 15s, disconnect for 5s (or you can use ac source for simulation), run continuously for 2 hours, the power module should be able to work normally ;
  2. The input voltage is the overvoltage point -5v, the power module has the maximum load, use the contactor to control the voltage input, close for 15s, disconnect for 5s (or you can use ac source for simulation), run continuously for 2 hours, the power module should can work normally;
  3. The input voltage is the undervoltage point -5v, the power module has the maximum load, use the contactor to control the voltage input, close for 15s, disconnect for 5s (or you can use ac source for simulation), run continuously for 2 hours, the power module should works fine.

Judgment Criteria:

In the above test, the power module works normally. After the test, the power module can work normally, and the performance has no obvious change, which is qualified; otherwise it is unqualified.

03 Input low voltage point loop test

 

Test description: The setting hysteresis of the input undervoltage point protection of the primary power supply module often occurs in the following situations: the input voltage is low, close to the undervoltage point of the primary power supply module, and the power supply module is turned off. Because of the resistance, the voltage will rise after the load is unloaded, which may cause the primary power module to be in a state of repeated development at low voltage.

testing method:

The power module runs with full load, the input voltage changes slowly from (input undervoltage point -3v) to (input undervoltage point +3v), the time is set to 5 to 8 minutes, and the power module should be able to work normally and stably. , continuous operation for at least 0.5 hours, the performance of the power module has no obvious change.

judgement standard:

The primary power module runs normally and continuously, and there is no obvious change in performance after at least 0.5 hours, and it is qualified; otherwise, it is unqualified.

04 Input transient high voltage test

 

Test description: The pfc circuit adopts the average value circuit for over-under-voltage protection, so when the input transient high voltage, the pfc circuit may quickly achieve protection, resulting in damage, test the stable operation ability of the power module under transient conditions to assess reliability.

testing method:

  1. For rated voltage input, use a dual trace oscilloscope to test the input voltage waveform and the overvoltage protection signal, the input voltage jumps from the power limit point plus 5v to 300v, read the number of cycles n before overvoltage protection from the oscilloscope, and use it as the following the basis for the test;
  2. Rated input voltage, the power module runs with full load, superimposes a voltage jump of 300v on the input, the number of superimposed cycles is (n-1), the superimposition frequency is 1 time/30s, and it runs for 3 hours in total.

judgement standard:

The primary power module can run stably under the above conditions without damage or other abnormal phenomena, and it is qualified; otherwise it is unqualified.

 

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