1、 Definition and Function
Energy Storage Converter (PCS) is a device specifically designed to control the charging and discharging processes of batteries, with the function of AC/DC conversion. It is composed of DC/AC bidirectional converters, control units, etc., and can achieve bidirectional flow of electrical energy, that is, converting direct current into alternating current, and can also convert alternating current into direct current. The PCS controller receives backend control instructions through communication and controls the inverter to charge or discharge the battery based on the symbol and size of the power instruction, thereby achieving the adjustment of active and reactive power in the power grid. In addition, PCS can communicate with the Battery Management System (BMS) to obtain battery pack status information, achieve protective charging and discharging of the battery, and ensure safe battery operation.
Uninterruptible power supply (UPS) is a type of uninterruptible power supply that includes energy storage devices, mainly used to provide uninterrupted power to some devices that require high power stability. When the mains power input is normal, UPS supplies the load with stabilized mains power and charges the internal battery; When the mains power is interrupted (due to an accident power outage), UPS immediately supplies AC power to the load by switching the DC energy of the battery through an inverter, maintaining normal operation of the load and protecting the load’s software and hardware from damage. UPS equipment usually provides protection against high or low voltage to avoid damage to electrical equipment caused by voltage fluctuations.
2、 Technical characteristics
Energy storage PCS has the characteristics of bidirectional current conversion, precise control, high efficiency and stability in technology. It can achieve flexible conversion of electrical energy, accurately control the charging and discharging process of the battery according to requirements, and ensure the safe operation of the battery. In addition, the energy storage PCS also has functions such as real-time monitoring and information management of battery pack status, intelligent charging and discharging management and optimization. It can obtain and monitor key parameters of the battery pack in real time, such as voltage, current, temperature, and internal resistance, and intelligently adjust charging and discharging strategies based on this information to achieve the best charging and discharging effect.
UPS focuses on functions such as power stability, emergency power supply, and overload protection. It can adjust voltage, current, and frequency when the power supply quality fluctuates or fluctuates greatly, ensuring stable output power and avoiding damage to electrical equipment. When a sudden situation leads to a power outage in the power grid, UPS can immediately switch to internal battery power supply mode to ensure the normal operation of the equipment. In addition, UPS also has overload protection function. When the equipment load exceeds the rated value, it will automatically limit the output current or cut off the output power to protect the equipment.
3、 Application scenarios
Energy storage PCS is mainly used in AC coupled energy storage systems such as grid connected energy storage and microgrid energy storage. In these systems, energy storage PCS regulate the active and reactive power of the power grid by controlling the charging and discharging process of batteries, thereby balancing the differences between supply and demand and achieving peak shaving and valley filling of the power system. In addition, energy storage PCS can also be combined with solar and wind power generation systems to store the electricity generated by the power generation system and release it when needed to smooth the output of the power generation system and improve energy utilization.
UPS is widely used in fields such as data centers, medical equipment, industrial automation, and communication equipment. In these fields, devices have high requirements for power stability. Once power is interrupted, it may lead to data loss, equipment failure, and even endanger life safety. Therefore, UPS has become an indispensable power guarantee equipment in these fields. It can provide stable and uninterrupted power supply to devices, avoiding equipment failures and data loss caused by power outages or fluctuations.
4、 Development trends
With the continuous development of renewable energy and energy storage technology, both energy storage PCS and UPS will have broader application prospects. Energy storage PCS will pay more attention to functions such as efficiency, stability, and intelligent control to meet the growing demand for energy storage and utilization. Meanwhile, with the continuous application of technologies such as the Internet of Things and big data, energy storage PCS will achieve more intelligent management and control, improving energy utilization efficiency. UPS will pay more attention to functions such as power stability and emergency power supply, and will also develop towards more efficient and environmentally friendly directions. In addition, with the popularization and application of new energy vehicles, UPS will also play an important role in fields such as electric vehicle charging stations.
5、 Summary
In summary, there are significant differences between energy storage PCS and UPS in terms of definition, function, technical characteristics, and application scenarios. Energy storage PCS is mainly used to control the charging and discharging process of batteries, achieve bidirectional flow of electrical energy, and regulate the active and reactive power of the power grid; UPS, on the other hand, is mainly used to provide uninterrupted power supply guarantee for devices that require high power stability. In practical applications, both have their own advantages and together provide important support for the stable operation of the power system and the efficient utilization of energy.