Application of EC300 Four Quadrant Intelligent Whole Machine In the Elevator Energy Saving Reformation in a Construction Site

Abstract:Through the application of EC300 four quadrant intelligent whole machine in the elevator energy reformation in a construction site in Wuxi, this article has reflected the energy-saving effect after adopting EC300 and the products features and advantages of EC300.

Keywords:four quadrant, energy saving, green and environmental protection, safe and comfortable

1. Preface
A building in Wuxi City adopts six elevator group control with high elevator usage frequency and frequent braking, the original inverter brake adopts the energy dissipation resistance with huge heat and energy consumption. In order to reduce energy consumption, now we conduct the energy-saving transformation to a lift, the original system will be replaced by EC300 four quadrant whole machine to achieve energy-saving effect.

2. Configuration and description before the transformation:
Elevator load 1350KG, speed 2.5m / s motor power 23.2KW, frequency power table 30KW, 30 layers 30 stations
The original system is the elevator controller + inverter + brake resistor
The usage place is an office building.

We all know that most of the elevators used in our country are traction elevators, the elevator car is on the one side and the balanced counterpoise is on the another side of the elevator. When the elevator is descending (or rising), braking is needed to keep the uniform or decelerate running. In the process, a large number of mechanical energy is changed into electrical energy via the motor, and it consumes the power in the form of heat energy via the brake resistor, resulting in a serious waste. The brake resistor emits heat and has a certain impact on the machine room temperature, it often needs to install air conditioning and ventilation equipment for the heat dissipation, which has increased more extra cost, following is the illustration of braking state.

Figure 2.1 the total weight of elevator car and people is less than the elevator counterpoise
Figure 2.2 the total weight of elevator car and people is more than the elevator counterpoise

Figure 2.3 The host and control cabinet before the transformation

3. Energy saving transformation program
The original system is all replaced by 30KW EC300 four quadrant intelligent whole machine, in the braking state of elevator, the power generated by motor is feedbacked to the power grid via the EC300 four quadrant feedback technology to achieve the purpose of energy saving, meanwhile the system external reactor, the feedback current harmonic<5%, to meet the green standards. As shown below:

Figure 3.1 the total weight of elevator car and people is less than the elevator counterpoise
Figure 3.2 the total weight of elevator car and people is more than the elevator counterpoise

Figure 3.3 The control cabinet after the transformation

4. Feedback principle of EC300 four quadrant intelligent whole machine

Inverting and rectification design principle of EC300 four quadrant intelligent whole machine EC300 rectifier part is IGBT six pulse control rectifier,in the electric state, after the bus is lifted to a certain degree, the energycan be feedbacked to the power grid to achieve the purpose of energy saving.

5. Energy - saving test methods and energy - saving ratestatistics
5.1 Adopted test equipment
1 set StandardelSDT871 bi - directional meter
5.2 Energy-saving rate calculation method
Energy-saving rate calculation method: power generation /(power consumption + power generation) * 100%
As shown in the following table on May 23, the measuredrate is calculated as follows:
The current cumulative generating capacity is 175.8
The current cumulative power consumption is 319.3
Saving rate:energy-saving rate calculation method: power generation / (power consumption +power generation) * 100% = 175.8 / (175.8 + 319.3) * 100% = 35.5%
5.3 Energy saving statistics

The elevator is put into use from April 28, 2016, the data statistics to May 23, we can see from the above data, the power generated by the motor after the usage of INVT EC300 products, the energy-saving rate can up to 35%.

The user of energy-saving electricity: the owners public lighting, fans, air conditioning, water pumps and other equipment, so the whole system is energy saving, that is in the same conditions, adopting four quadrant products can save more than 30% electricity per month for the owners. The energy saving is more pronounced in the following case

a.the higher floor the elevator is, the more frequent braking , the more energy saving;

b.the new installation of the elevator, the larger mechanical inertia, the more energy saving;

c.the longer the elevator is used, the greater friction is, the more energy saving;

d.the faster the elevator is, the more frequency brake, the more energy saving;

e.the more frequent the elevator is used, the more frequent brake, the more energy saving.

f.product highlights of EC300 four quadrant intelligent whole machine

1.More efficient energy saving

The driver uses the six-pulse controllable rectifier, which has the power supply feedback function. When the elevator control system is in the power generation state, the regenerative energy is fed back to the power grid via the energy feedback technology (without braking resistance, the braking heat loss is converted into electrical energy).

To achieve the purpose of energy conservation, power saving rate up to 30%, energy saving efficiency is relative to the elevator power, the whole elevator system, the elevator balance system and other aspects, the energy efficiency is better in the following circumstances.

2.More safe and comfortable

a.Safe hardware enable detection, in line with EN81 standard;

   When the safety and door lock detection time of 1ms, running when the security or door lock switch action in the elevator, direct block IGBT to avoid contactor arcing;

b.The system uses dual-core control, high communication speed, fast curve tracking, high control accuracy, high security redundancy;

Functional safety can meet the SIL3 standard (extended STO card);

c.Shaft switch and position real-time monitoring to prevent the fault layer operation

d.Output short circuit protection

The elevator output shorts out at rated load and the system is immediately protected to avoid the damage to the machine

3.High voltage input

The system has a safety circuit high-pressure detection, car door lock loop high-pressure detection, hall lock loop high-pressure detection

a.Brake force self-detection function, perfect UCMP car accidental protection program;

b.Advanced torque ripple suppression technology, dead zone compensation technology, current sampling, current loop control technology, notch filter, speed observer, to enhance the operation comfort and reduce the running noise;

c.Shaft switch and position real-time monitoring to prevent the fault layer operation.

4.More green and environmental protection

a.AFE active front end, feedback current harmonics <5%

System external reactor, ensure that the feedback current harmonic <5%, in line with IEC61000-3-2 and GB / T14549 requirements for the power grid harmonic, replacing the traditional braking resistor energy consumption.

b.Configuration of the system to make the elevator manufacturers easier get "VD44707" elevator energy consumption A-level certification

5.More intelligent and reliable

a.Intelligent learning

   Motor current loop intelligent learning, hoist floor and switch intelligent learning, door machine logic intelligent learning, call-out address self-adaptive

b.Fault classification processing, braking force intelligent detection

c.Built-in data black box

    The system monitors and records the running status of the elevator in real-time. When the elevator appears an instant fault, it can record the running state of the elevator before the fault and the running state after the fault, it’s convenient for analyzing the reason.

d.Configurable i-ESM elevator safe operation monitoring and management system

    Simple configuration, that is, easy to use, you can achieve remote alarm, fault analysis statistics and fault early warning function to facilitate maintenance personnel to maintain the elevator and guide the maintenance personnel quickly troubleshooting

6.More convenient and easy to use

a.Various debugging tools

Support a variety of debugging tools (LCD operator, mobile phone APP, PC computer, remote expert assistance)

b.Synchronous mechanical potential static recognition technology

c.High performance no load cell starting compensation technology

d.Encoder direction automatic judgment

7.More economical and compact

Through product integration design, integrate the controllable rectifier, inverting in a module, the structure is more compact and cost-effective

8.Conclusion

With the sustainable development of national economy, elevators is now more and more used, in the electricity survey statistics of hotel, office buildings, the elevator electricity consumption accounts for 17% -25% of total electricity consumption, which is lower than the air conditioning electricity consumption, but higher than the lighting, water supply and other electricity consumption.

At present, in the foreign nations, elevators have been divided into " Energy dissipation type" and advanced "feedback type", when the customers purchase elevator, more and more people select the "feedback" type elevator, so the application of four quadrants inverter in the elevator industry will be more and more extensive.

References:

 [1] EC300 four quadrant intelligent whole machine manual: INVT Elevator Control Technology (Wuxi) Co., Ltd.

 [2] EC300 four quadrant intelligent whole machine quick debugging manual: INVT Elevator Control Technology (Wuxi) Co., Ltd.