The working principle of Schneider SPM6KL online UPS power supply mainly involves rectification, inversion, charging, battery management, monitoring and protection, and other aspects, as follows:
1. Rectification and filtering
AC to DC conversion: When the mains power is input normally, SPM6KL first converts the input AC power into DC power through a rectifier. Rectifiers are usually composed of a set of diodes or thyristors, which utilize their unidirectional conductivity to convert the positive and negative half cycles of AC power into unidirectional DC power, providing stable DC power for subsequent circuits.
Filtering processing: After rectification, the DC power will have certain ripples and noise. In order to obtain a purer and more stable DC voltage, the filtering circuit will filter the rectified DC power. Filter circuits are generally composed of components such as capacitors and inductors. By storing and releasing electrical energy, they smooth the fluctuations of DC voltage, reduce the ripple coefficient of voltage, and provide high-quality DC input for inverter circuits.
2. Inverter and output
DC to AC: The inverter circuit is one of the core components of UPS power supply, which converts rectified and filtered DC electricity into. AC power output to supply power to load equipment. Inverter circuits typically use switching devices such as power MOSFETs or field-effect transistors. By controlling the conduction and cutoff of these switching devices, the DC voltage is converted into a high-frequency pulse width modulation (PWM) signal. Then, through filtering and shaping circuits, the PWM signal is converted into a sine wave AC power and output to the load.
Voltage and frequency stabilization: The online UPS power supply monitors the changes in output voltage and frequency in real time through a precise control circuit, and compares them with the set standard values. When there is a deviation in the output voltage or frequency, the control circuit will automatically adjust the working parameters of the inverter circuit to maintain stable output voltage and frequency, ensuring that the load equipment can work normally in a stable power environment.
3. Battery Charging and Management
Charging control: When the mains power is normal, the UPS power supply not only supplies power to the load, but also charges the battery pack through the charging circuit. The charging circuit will automatically adjust the charging current and voltage based on the type, capacity, and current charging status of the battery, using appropriate charging methods such as constant current charging, constant voltage charging, etc., to ensure that the battery can be fully charged quickly and safely.
Battery monitoring and protection: UPS power supply is equipped with a built-in battery monitoring circuit, which can monitor the voltage, current, temperature, etc. of the battery pack in real time. Parameters. When the battery experiences abnormal conditions such as overcharging, overdischarging, short circuit, high temperature, etc., the monitoring circuit will promptly issue an alarm signal and take corresponding protective measures, such as stopping charging, cutting off the battery circuit, etc., to extend the battery’s service life, prevent battery damage or safety accidents.
4. Handling of mains power faults
Mains power interruption: When the mains power is suddenly interrupted, the UPS power supply will immediately switch to battery power mode, and the battery pack will continue to provide power to the load through the inverter circuit. Due to the online UPS power supply, the inverter is always in operation when the mains power is normal. Therefore, in the event of mains power interruption, it can switch to battery power without interruption, ensuring that the load equipment will not shut down due to mains power interruption.
Abnormal mains power supply: If the mains power supply experiences low or high voltage, abnormal frequency, or waveform distortion, the UPS power supply will automatically detect it. Cut off the quality of the mains power and handle it according to the preset threshold. When the degree of abnormal mains power exceeds the allowable range, the UPS power supply will switch the load to battery power mode to avoid damage to the load equipment caused by abnormal mains power.
5. Monitoring and protection functions
Monitoring System: The SPM6KL online UPS power supply is equipped with a monitoring system, which allows users to view the working status, input and output voltage, current, battery level, load rate, and other information of the UPS power supply in real time through a LCD screen or communication interface. At the same time, the monitoring system can also record the operation history data of UPS power supply, such as mains power interruption records, battery charging and discharging records, etc., which facilitates users’ fault diagnosis and maintenance management.
Protection function: In order to ensure the safety of UPS power supply and load equipment, SPM6KL has multiple protection functions, including input overvoltage protection, input undervoltage protection, output overvoltage protection, output undervoltage protection, overload protection, short circuit protection, overheating protection, etc. When an abnormal situation occurs, the protective circuit will quickly act to cut off the corresponding circuit, prevent equipment damage or safety accidents, and notify the user through the alarm system.