What are the main reasons for the hot hand of LED switching power supply during use?

Heat generated during normal operation

1.Power loss. When the switching power supply is working, the internal electronic components (such as transistors, diodes, etc.) will produce power loss due to the current passing through, and then generate heat. These heat will be transferred to the power supply housing, making the power supply heat up.

2.Electromagnetic induction heating occurs when magnetic components like transformers in LED switching power supplies operate. When current flows through a transformer's primary coil, it generates a magnetic field that induces voltage in the secondary coil. During this process, the transformer generates heat due to hysteresis losses and eddy current losses. Hysteresis losses arise from magnetic hysteresis in ferromagnetic materials, where energy consumption during magnetic domain reorientation generates heat. Eddy current losses occur when magnetic field variations induce circulating currents in the transformer's core and other conductive materials, producing heat through their flow. For example, in high-frequency switching power supplies, the transformer's high operating frequency results in significant hysteresis and eddy current losses, causing the transformer to overheat and subsequently raising the entire power supply's temperature.

3.The switching frequency determines the operation of switching power supplies, named after their internal components' switching mechanisms. Higher switching frequencies mean electronic components perform more switching operations per unit time. While this boosts efficiency by reducing component sizes like transformers, it also increases switching losses. Each switching cycle generates energy dissipation, which is converted into heat during the process.

Abnormal conditions cause fever

1.Component failure: When an internal component in an LED power supply fails, it may cause abnormal overheating. For instance, aging capacitors may experience changes in capacitance and increased internal resistance. When current flows through them, these capacitors with higher internal resistance consume more energy and generate heat. Additionally, if a transistor fails (e.g., short-circuit), the current surges dramatically, leading to sharp increases in power loss. The resulting heat rapidly raises the power supply's temperature. Moreover, this failure-induced heating can damage other components, further exacerbating the overheating issue.

2.Effective heat dissipation is critical in LED switching power supplies. When the cooling fan malfunctions or heatsinks become clogged with dust, heat cannot be efficiently expelled. Normally, heatsinks transfer heat generated by components to the surrounding air, but dust blocks this process. It's like putting on a thick "coat" over the heatsinks, trapping heat inside the power supply and causing it to overheat and become uncomfortably hot to touch.