Switching power supply is a kind of electronic equipment that converts alternating current into direct current and is widely used in various electronic equipment and systems. Since switching power supply will be affected by various electrical and environmental parameters during the working process, a series of protection measures are needed to ensure its safe and reliable operation. The following are some of the commonly used protections for switching power supplies:
1. Overload protection
Overload protection is one of the most basic protection measures for switching power supplies. When the load current exceeds the rated current of the switching power supply, or when a short-circuit fault occurs, the overload protection will immediately cut off the power supply output to prevent the power supply device from overheating or damage. Generally, overload protection is realized by using overcurrent protector, current sensor and other devices at the output of switching power supply.
2. Over-temperature protection
Over-temperature protection means that when the internal temperature of the switching power supply exceeds a certain limit, the power supply output will be cut off automatically to prevent the power supply device from overheating and causing damage. Over-temperature protection is usually realized by installing temperature sensors inside the power supply, once the temperature exceeds the set value, the protection circuit will cut off the power output.
3. Over-voltage protection
Over-voltage protection means that when the input voltage exceeds the rated voltage range of the switching power supply, the output of the power supply will be cut off automatically to prevent the abnormal power supply voltage from causing damage to the load circuit. Over-voltage protection is generally realized by using over-voltage protector, voltage sensor and other devices at the input of the switching power supply.
4. undervoltage protection
Undervoltage protection refers to when the input voltage is lower than the rated voltage range of the switching power supply, automatically cut off the power supply output, in order to prevent the power supply can not work properly and cause damage to the load circuit. Undervoltage protection is generally realized by using undervoltage protector, voltage sensor and other devices at the input of switching power supply.
5. Transient protection
Transient protection refers to the power supply input when an instantaneous voltage or current sudden change occurs, through the power supply output is quickly adjusted to avoid transient interference on the load circuit damage. Transient protection is generally realized by using transient protector, transient voltage suppressor and other devices at the power input.
6. Short circuit protection
Short-circuit protection means that when a short-circuit fault occurs at the output of the switching power supply, the power supply output is cut off immediately to prevent the power supply device from overheating or damage. Short-circuit protection is usually realized by using short-circuit protector, current sensor and other devices at the output of the switching power supply.
7. Overcurrent protection
Overcurrent protection means that when the output current of the switching power supply exceeds the rated current or the load current is too large, the power supply output will be cut off automatically to protect the power supply and load circuit from damage. Overcurrent protection is usually realized by using overcurrent protector, current sensor and other devices in the circuit.
8. Start-up protection
Start-up protection refers to the monitoring of the output voltage to ensure that the output voltage works stably within the set range when the switching power supply is first powered up and started. If the output voltage is abnormal, the start-up protection will immediately cut off the power output to avoid damage to the load equipment. Start-up protection is usually a protection function that comes with the switching power supply system.
In summary, several protections commonly used in switching power supplies include overload protection, over-temperature protection, over-voltage protection, under-voltage protection, transient protection, short circuit protection, over-current protection, and start-up protection. Together, these protections ensure the safe and reliable operation of switching power supplies and prevent unpredictable failures from causing damage to equipment and systems. When designing and selecting a switching power supply for different application scenarios, it is necessary to comprehensively consider the characteristics and requirements of the various protection functions in order to achieve the best protection effect.