As the core power component in fields such as industrial testing, medical imaging, and semiconductor manufacturing, the long-term load operation stability of high-voltage power supplies directly determines the reliability of downstream equipment. Aging testing is not a simple power-on "burn-in", but a key process to screen out early failure products by simulating extreme working conditions. Compared with consumer-grade power supplies, the aging testing of industrial-grade high-voltage power supplies focuses more on refined parameter monitoring and multi-dimensional working condition simulation. The following several easily overlooked inspection steps are precisely the core to determine the effectiveness of aging testing.

1. Precise Calibration of Bias Voltage Stress Application

Bias voltage aging is a unique testing link for high-voltage power supplies. Different from the conventional constant voltage and constant current testing, it needs to set the output voltage to 1.2-1.5 times the rated value to accelerate the aging process of components. The key of this step is not to simply increase the voltage, but to real-timely calibrate the voltage stress applied to the power module through a high-precision programmable power supply.

During the test, it is necessary to use a differential probe to monitor the voltage fluctuation across the power switch tube to avoid device breakdown caused by voltage overshoot. At the same time, the bias time should be adjusted according to the topological structure of the power supply. For example, the bias aging time of the resonant high-voltage power supply needs to be extended by 30% compared with the hard-switching power supply, so as to fully expose the loss problem of the capacitor inside the resonant cavity. Many manufacturers ignore the precise control of voltage stress, resulting in the failure of aging tests to effectively screen out products with hidden faults.

2. Dynamic Parameter Capture Under Full Working Condition Cycle

Aging test under a single working condition is difficult to simulate the actual working scene of high-voltage power supply, so cycle aging test has become a core inspection step. This step requires the power supply to cycle switch among four working conditions: constant voltage, constant current, no-load and overload, and the switching frequency should match the actual operating frequency of downstream equipment.

During the test, it is necessary to focus on capturing the voltage response time and current overshoot at the moment of working condition switching, which directly reflect the stability of the power supply control loop. For example, in the test of high-voltage power supply for semiconductor ion implantation equipment, when the working condition switches from constant current to constant voltage, the voltage overshoot should be controlled within ±0.5%, otherwise it will affect the energy accuracy of the ion beam. Recording the parameter changes in each cycle through a high-speed data acquisition card can effectively find the temperature drift problem of the feedback resistor in the control circuit.

3. Thermal Characteristic Monitoring in Closed Environment

The power density of high-voltage power supplies is generally high, and the heat dissipation capacity in a closed environment directly determines its service life, so thermal characteristic monitoring is a key step in aging testing. This step requires placing the power supply in a closed chassis simulating the actual installation environment, and monitoring the temperature distribution of key components such as power devices, transformers and filter capacitors through a thermistor array.

During the test, we should not only pay attention to the maximum temperature of a single point, but also analyze the temperature gradient. For example, the temperature difference between the transformer core and the winding should be controlled within 15℃, otherwise it will accelerate the aging of the insulation layer. At the same time, it is necessary to record the temperature change curve over time. When the power supply enters thermal steady state, the temperature fluctuation range should be less than ±2℃. Some manufacturers only monitor the shell temperature and ignore the temperature distribution of internal devices, resulting in product failure due to local overheating in actual use.

4. Parameter Consistency Verification After Aging

The aging test is not qualified by the non-damage of the power supply, and it is more important to verify the consistency of parameters before and after aging. This step needs to compare the core indicators such as voltage accuracy, current ripple and efficiency of the power supply before and after aging, and the parameter change rate should be controlled within 1%.

For example, if the change of tube voltage accuracy of the high-voltage power supply for medical X-ray machines exceeds 0.8% after aging, it will directly affect the definition of X-ray imaging. Full-parameter retesting with high-precision digital multimeters and oscilloscopes, combined with statistical methods to analyze the parameter dispersion of products in the same batch, can effectively evaluate the stability of the power supply production process. Many manufacturers omit this step, resulting in large differences in the reliability of products in the same batch.

The aging test of high-voltage power supply is a systematic project. The above four steps are interrelated and indispensable. Only through refined quality inspection can the long-term reliability of high-voltage power supplies be truly improved, escorting the stable operation of downstream high-end equipment.

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