Introduction; Functional Explanation; Principles Of Operation - GE Digital Energy LP 31 Series Product Description

1. INTRODUCTION

The LP 31 Series / 8 – 10 – 15 - 20 kVA UPS series is a compact, truly On-line 3-phase in 1-phase out
system which incorporates the most advanced power electronics technology to provide exceptional
protection for electrical equipment.

2. FUNCTIONAL EXPLANATION

2.1 Principles of Operation

The UPS stores electric energy in batteries housed in the unit.
This allows the system to supply output power even when the incoming mains power is cut off
completely.
Energy is stored as Direct Current (DC), but input and output energy must be Alternating Current (AC) in
sine wave form.
The UPS therefore contains an input converter (AC to DC) and an output converter (DC to AC) (Figure 1).
The LP 31 Series / 8 – 10 – 15 - 20 kVA UPS is a SECOND GENERATION On-line UPS with:
• battery not in line with the DC link, resulting in:
- enhanced battery life;
- optimal battery charging;
• full wave input converter with power factor correction;
• extremely wide input voltage and input frequency tolerance;
• output converter (inverter) using IGBT technology.
The UPS needs two separate mains:
One three phase + neutral input mains and a single phase bypass mains. The neutral is essential.
Modifications reserved
PRD_LPS_31E_8K0_20K_1GB_V021.doc
Figure 1 - Block diagram of the LP 31 Series / 8-10-15-20 kVA UPS, mains present
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Product Description LP 31 Series