Mr. Amir Bahram DARAEİ - Job responsibilities are CTO is Arian Asansor Co. and CEO in Part Danafoss Co.

daraei@arianasansor.com  - www.linkedin.com/in/amir-bahram-41ab2b35

Mrs. Mojgan FATEMİ - Sales manager in Part Danafoss Co.

fatemi@partdanafoss.com -www.linkedin.com/in/mojgan-fatemi-755982231

1. Introduction

Saving energy in elevator is very important and different brands compete for saving in energy. In this rivalry, the index is energy label determined after launching based on VID4707 Standards which is usually examined by Standby and Running.

The purpose of this paper is examining different conditions for decreasing energy consumption and increasing efficiency in emergency rescue state which is assessed from different aspects.

2. Effective elements in emergency rescue mode
The following diagram thoroughly illustrates effective elements:

As we see the main elements include the four mentioned elements and in the following the role of each element will be presented with details.

2-1) Using drive which smart UPS function
Using a drive which its direction detection algorithm is optimal. One of the best methods is that the software should be smart always saving the consumption rate of the elevator and according to the starts it understands that during black out which direction has less consumption rate.

2-2) Using smart control system
During black out the purpose is the elevator movement and reaching the elevator to the floor and taking out the passenger.

Therefore, we can create a more optimal movement by changing movement diagram (acceleration and jerk).

Therefore, after detecting the black out by control system, it can inform the drive and change the amounts of acceleration, jerk and so on and create faster movement with lower energy consumption .

This can be done easily with high precision and quality when the drive and control board have serial communication in the context of Modbus or Can bus.

2-3) Using UPS with high efficiency
If the UPS output is a complete sinuous ware form its efficiency increases, of course this UPS model raises the cost and we should evaluate if this change is appropriate or it is better to use UPS with semi-sinuous waveform.

In addition to output waveform, two other factors can add to the capability and intelligence of the system that we examine it in the following:
• Smart charger based on new algorithms and it can increase the life time of batteries.
• Serial communication between control system and UPS. This can facilitate transferring the information of two systems and in addition to reporting battery condition, we can make the elevator smart and movement efficiency increases during black out.

2-4) Battery
Battery is very important in emergency rescue system and because of that in this paper we examine it from different aspects:

2-4-1) Building battery and evaluating the builder
One of the most steps in the quality of every product is the used methods and raw materials in producing the product. For the battery, this is very important. The producer should have a good experience in producing this product according to European standards (CE) and they should have valid certificate in guaranteeing the quality and they should increase the quality of product by rigorously testing the raw materials and final product. The buyer should pay attention to the mentioned issues and consider the battery weight and its date of manufacture as these two factors are highly important for life time and quality of the battery. Meanwhile by the help of the smart machines, we can measure the ampere hour (AH) of batteries through sampling.

2-4-2) Charger
Generally, there are four methods for charging sealed acid batteries that we explain them breifly in the following:

1-Fixed voltage charger: this method is one of the most common for charging sealed acid batteries. It should be mentioned that the firstcharge current should be restricted so that the battery wouldn’tbe damaged.

2-Fixed current charger: we can use this method for a 2V cell and for charging a number of cells connected serially it isn’t recommended in batteries.

3-Conical current charger: this method isnot recommended for sealed acid batteries as it often can decrease the battery life time due to weak control of final charger voltage. Of course according to the simplicity of circuit and low cost of charging, the number of serial batteries are used. In this method it is recommended that the time of charge is limited and controlled.

4- Fixed voltage two-steps charger: this method is recommended for charging sealed acid batteries in short time and finally it keeps them in “suspended” charging (ready to use) state.

Each of the above mentioned methods has its own benefits and disadvantages. But by using a simple charger design, it wouldn’t be cost effective in long term. Examining the battery condition, replacing the battery are costly and non-environmental. Therefore, designing charger for maximizing battery longevity is very important. Another important factor that we should consider about sealed acid battery is its temprature. When the temprature increases, the electrochemical activity increases in a battery as its charger increases the voltage to prevent enegy loss.Using a combination of fixed corrent and two techniques of fixed voltage charger and also by monitoring voltage and temperature of battery we can propose a multiple stage charger for decreasing stress on the battery in the shortest time.

2-4-3)Environmental conditions
As an ideal condition for use and battery function, we can refer to 20 degrees centigrade. According to the following graph, when the temperature reaches from 25 to 35 degrees about 50% of battery service life decreases. We recommend you to consider the appropriate ventillation conditions and environment temprature and pay attention to factors like putting the battery close to heating equipment putting the battery inside closed box or direct sunlight (note that the battery should at least have 100 centimeters away from lateral barriers).

2-4-5) Consumer duties
Note the above graph, you observe that if environment temperature comes down then storage time increases. of course in this subject presupposes that the capacity is 100% at the earlier time of storage and by passing time and increasing environmen temperature, the battery capaciy decreases.

Another important issues examining and inspecting the battery periodically. In each inspection, it should be noted that connections between the batteries are stable and conductor section of the batteries shouldn’t be oxidized and also the battery shouldn’t be too hot or swollen.Increase of oxidation, at first take out the battery from circuit and then clean the battery conductor setion with hot water and abrasive to maintain its conductivity at the conductor setion and during cleaning the battery conductor section, keep the sulfate off from skin or clothes. It should be noted that by observing the above instructions, the battery efficient life service increases and we use optimally the total battery capacities.

Summary
In each control system, if we have the stronger serial connection , then elevator becomes smarter. If we use these capabilities, we can have a normal movement with limited start times in blackout by increasing UPS power.