Type of emergency power supply

When industrial and civil buildings are in fire emergency state, in order to ensure the success of fire fighting, the independent power supply that is responsible for supplying power to fire electrical equipment is called emergency power supply. The Code for Electrical Design of Civil Buildings clearly stipulates that the first level load shall be powered by two power supplies. When one power supply fails, the other power supply shall not be damaged; The power forms of the first level load include two high-voltage power supplies, one high-voltage power supply and one low-voltage power supply, diesel generator set or battery pack; In addition to the above two power supplies, the emergency power supply must also be added for the special important load in the first level load.

Types of common emergency power supply

1. EPS emergency power supply: It is an emergency power supply composed of charger, inverter, storage battery, isolation transformer, change-over switch and other devices that reverses DC power into AC power. It is applicable to the load with the allowable interruption time of more than 0.25s.

2. UPS: It is mainly a static AC uninterruptible power supply device composed of power converter energy storage device (battery) and switch (electronic and mechanical) to ensure power supply continuity. It is applicable to the load with millisecond interruption time.

3. Self provided emergency diesel generator set: it is a power generation equipment composed of diesel engine driven power frequency AC synchronous generator. The fast self starting generator set is applicable to buildings with a power interruption time of more than 15s. The working time of the emergency power supply shall be considered according to the power failure time allowed in production technology. When it is used in conjunction with the automatically started generator set, it shall not be less than 10min.

4. Special feeder line with automatic switching device independent of normal power supply. The action time applicable to the automatic switching device can meet the emergency power supply with the allowable interruption time of 1.5 s or more. If DC power supply is possible to be used for particularly important loads with millisecond power outage and small capacity, battery pack shall be used as emergency power supply.

5. Self provided emergency gas turbine generator unit; It is a power generation equipment driven by gas turbine and driven by power frequency AC synchronous generator.