EPS solution based on Delta inverter

1 Introduction
EPS (Emergency Power
Supply) is the abbreviation of emergency power supply. EPS is widely used in industrial and civil buildings, where sudden power outages will cause significant economic losses to normal production and life. It is an important part of modern building safety protection facilities. EPS is generally used as a backup power supply for firefighting or production in emergency situations. For example, in high-rise buildings, shopping malls, hospitals, rail transit, underground shopping malls and other places with many people, few exits and limited natural light sources, once a fire occurs or the power grid is damaged, the light source disappears and it is pitch black. At the same time, there are many people and few exits, and the consequences will be disastrous. At the same time, the fire brigade will be unable to carry out disaster relief work due to the lack of power supply, which will aggravate the degree of the disaster. It can be seen that EPS plays an increasingly important role in the safety of modern society and is
the guardian of the "urban lifeline system".

At present, EPS adopts different control methods and control means. The loads carried by EPS can be summarized into three types: one is EPS mainly used for emergency lighting and accident lighting; the second is three-phase series EPS used for mixed loads such as air conditioners, elevators, rolling doors, exhaust fans, and water pumps in addition to emergency lighting and accident lighting; the third is variable frequency series EPS that directly supplies power to motors. This article introduces the most comprehensive three-phase series EPS power supply for mixed loads.
2 EPS system based on Delta inverter
Delta EPS solution mainly uses inverters to play the inverter AC motor drive function of the fan, water pump, rolling door of the fire protection system. Delta EPS customized dedicated inverter can truly realize the connection of the common DC bus, so it can be applied not only to the EPS industry, but also to the chemical fiber and glass manufacturing industries. Delta dedicated inverter and synchronous card are used in combination to achieve the same input and output phases, thus meeting the application of special occasions. In view of the particularity of motor drive in the EPS industry, Delta inverter mainly adds parameters such as automatic torque compensation, torque compensation limit, and abnormal restart to meet the needs of special industries. The EPS charging module matched with the inverter reduces the cost for customers, reduces the heavy transformer and reduces the transportation cost.
2.1 Overview of EPS special machine
One of the main features of Delta EPS special machine is that it can realize the common DC bus, thus expanding the application field of EPS special machine. At the same time, the DC conversion of the internal contactor and soft start circuit meets the battery direct start requirement of EPS special machine. Delta EPS special inverter can form a highly reliable hybrid load special inverter by matching with appropriate low-pass filter and transformer. And ensure the output voltage stability and waveform smoothness of the inverter. Delta EPS emergency power supply special inverter must meet the application of most occasions in the EPS industry and is the first choice of EPS manufacturers.
2.2 Functional features of Delta EPS special machine
(1) The auxiliary power supply and soft start circuit contactor of the inverter are all DC, so direct DC power supply can be fully realized.
(2) Super strong hardware and software protection functions ensure the reliability of the inverter.
(3) It contains multiple modulation modes, so it can be used with a variety of transformers, thus ensuring that the output voltage waveform is closer to a sine wave.
(4) Delta EPS dedicated inverters have two specifications: AC380V and AC220V, with a power range from 0-220KW, which can meet the needs of customers in different occasions.
(5) The use of synchronization cards ensures that the input and output phases are the same.

2.3 Delta EPS dedicated inverter application design
(1) Electrical principle design. The principle of the EPS with AC and DC dual power supply is shown in Figure 1. The principle of the EPS with DC single power supply is shown in Figure 2.