Introduction

HTFPL electronic load bank with energy-feedback function is an advanced functional load testing equipment for UPS, generator sets, power supplies. It can serve as the harmonic and reactive compensation tester for the AHFs and SVGs or work together with generator test bench.

It employs modular design concept and is based on IGBT-based AC-DC-AC converter topology with capacity up to 600A per cabinet.

Challenges of Traditional Resistive Load Bank

Performance test, aging process and load testing are indispensable steps for manufacturing of equipment including:

● Voltage stabilizers

● UPS

● DC power supplies

● Battery chargers 

● Diesel generators 

Traditional method to do so is simply using resistors as loads. This method causes large power loses during those processes. 

In addition, in many occasions, more complex non-linear load profiles with specific power factor requirement, such as three-wire rectifier and four-wire rectifier, are needed for aging or performance test purpose. Besides that, during aging process and performance test of Active Harmonic Filters (AHF) and Static Var Generators (SVG), a simulated load with programmable parameters including three-phase active power unbalance, reactive power, harmonic orders are required. For these two purposes, traditional resistive 

How Does HTFPL Work?

To solve the power losses issue and provide complex load profiles mentioned above, Hoteam HTFPL electronic load banks with energy-feedback function are the foolproof solution.

HTFPL electronic load bank with energy-feedback function employs modular design concept and is based on back-to-back AC-DC-AC converter topology. Specifically, one load unit and one regenerative unit are connected in pair and then several such load/regenerative pairs operate in parallel. And all load units are connected to three-phase, four-wire grid via load bus while the regenerative units being connected to three-phase, three-wire grid via feedback bus. The DC buses with same polarity of the load unit and regenerative unit of each pair are connected. 

The HMI controls and monitors all load/regenerative pairs via RS485 bus. When simulating low-current load, only one load/regenerative pair will operate alone and when simulating high-current load, multiple load/regenerative pairs will work together. Every pair can adjust the output current independently to ensure output accuracy. 

The current waveform characteristics of common load types have been pre-stored in the controller of every load unit and can be loaded with one touch via HMI. Moreover users can customize load current via self-programming function on the HMI. 

When simulating load step change, all load units are synchronized by signals transmitted via glass fibers to ensure good synchronization.

Features

- Capability of simulating multiple load types 

● Resistive loads, inductive loads, capacitive loads and the combinations of those three load types 

● Unbalanced loads such as single-phase loads connected between L-N or L-L

● Three-phase, four-wire rectifiers and single-phase rectifiers 

● Three-phase, three-wire, six-pulse rectifiers and three-phase, three-wire, twenty-pulse rectifiers 

● Single-phase and three-phase generators 

● Loads with current waveforms customized by user 

● Step-change load with programmable step speed to ease the response time test of tested samples 

- The control accuracy >97% for whole output range from 30A to 600A 

- Modular design concept for higher availability and easy maintenance

- High energy efficiency 

● Patented constant-frequency PWM technology for low ripple current and power losses 

● Energy efficiency higher than 92% at full load condition 

● Energy feedback function feedback the active power into grid 

- User-friendly HMI and easy operation 

● Common load types can be loaded with one button on HMI 

● Multiple load profiles prestored and can be programmed by user 

● User program can be stored for future use 

● Centralized control of all load units can be done via the HMI. Any unit can be powered on and off dependently on