WP6-Brochure-E4 brochure - ELA European Lift Association.

More documents

Recommendations

Info

3 Emerging lift and escalator technologies As already mentioned, technologic development in the lift industry has been mainly driven by factors other than energy efficiency. Safety, travel speed, acoustic noise, ride comfort and occupied space are, traditionally, the main concerns in lift design. However, the demand for energy efficient products and greener buildings has grown, in the last few years, and the lift industry responded accordingly, presenting its customers with solutions that meet these growing demands. Rising electricity prices have also been a major contribution to the demand for more energy efficient solutions. In some applications, electricity costs amount to many times the initial cost of the equipment and, therefore, investing in an energy efficient lift is often cost‐effective in high traffic applications. Energy efficient technological developments take different approaches that tackle different causes for inefficiencies in vertical transportation systems. These causes can be divided into two major groups: direct and indirect. Direct causes are the ones that can be directly related to the equipment. The most common direct losses are: • Friction losses; • Transmission losses; • Motor losses; • Brake losses • Lighting losses • Controller losses Indirect causes are related to the operation of the equipment and are associated with user behaviour or traffic management options. In this section, a brief description of energy efficient technologies applied to lifts is made. 3.1 Premium Efficiency Induction Motors In the past, brushed DC motors were the technology of choice for lifts because they are easy to control, providing the best ride quality and an accurate levelling. Due to increasing stringent regulations worldwide, induction motors have been subject to major efficiency improvements in the last decades. Induction motors have a lower cost, are more robust and require much less maintenance than DC motors. 16
High efficiency motors are typically constructed with superior magnetic materials, larger magnetic circuits with thinner laminations, larger copper/aluminium cross‐section in the stator and rotor windings, tighter tolerances, better quality control and optimised design. These motors, therefore, have lower losses and improved efficiency. Because of lower losses, the operating temperature can be lower, leading to improved reliability [1]. Some of the options to increase induction motors efficiency are presented in Figure 3‐1. Figure 3‐1. Options to increase the efficiency of induction motors [2] Stator losses can be reduced by increasing the cross‐section of stator windings which lowers their electrical resistance reducing I²R losses. This modification is where the largest gains in efficiency are achieved. High efficiency motors typically contain about 20% more copper than standard efficiency models of equivalent size and rating. Increasing the cross‐section of the rotor conductors (conductor bars and end‐plates) and/or increasing their conductivity (e.g. using copper instead of aluminium), and to a lesser extent by increasing the total flux across the air gap between rotor and stator reduces the rotor losses. Magnetic core losses occur in the steel laminations of the stator and rotor and are mainly due to hysteresis effects and to induced eddy currents. Both types of losses approximately increase with the square of the magnetic flux density. Lengthening the lamination stack, which reduces the flux density within the stack, therefore reduces core losses. These losses can be further reduced through the use of magnetic steel with better magnetic properties (e.g. higher permeability and higher resistivity) in the laminations. Another means to reduce the eddy currents magnetic core losses is to reduce the laminations’ thickness. Eddy current losses can also be reduced by ensuring an adequate insulation between laminations, thus minimising the flow of current (and I²R losses) through the stack. 17
Page 1 and 2: E4 ENERGY EFFICIENT ELEVATORS AND E
Page 3 and 4: Contents 1 Introduction ...........
Page 5 and 6: 1 Introduction Means of vertical tr
Page 7 and 8: 2 Lift and Escalator Technologies T
Page 9 and 10: Figure 2‐3. Configuration of Gear
Page 11 and 12: Some manufacturers have gone even f
Page 13 and 14: • Conventional hydraulic units do
Page 15: [2] Sachs, H., “Opportunities for
Page 19 and 20: Figure 3‐3. Effect of load on pow
Page 21 and 22: If the linear motor is mounted on t
Page 23 and 24: 3 Phase AC input 50 Hz AC/DC Conver
Page 25 and 26: preventing the car from falling. Ty
Page 27 and 28: Figure 3‐14. Regenerative operati
Page 29 and 30: occupied by lift support systems. A
Page 31 and 32: Figure 3‐19. Possible configurati
Page 33 and 34: After the introduction of relay log
Page 35 and 36: It is evident that the way lifts ar
Page 37 and 38: When combined with hall call contro
Page 39 and 40: of the torque of the 1:1 roping sch
Page 41 and 42: times as quickly as a 720 mm sheave
Page 43 and 44: LEDs are also a very efficient solu
Page 45 and 46: • Car electronics • Light curta
Page 47 and 48: The major cause of energy consumpti
Page 49 and 50: 3.9 Efficient Escalators and Moving
Page 51 and 52: These bearings feature optimised in
Page 53 and 54: 4 Market Characterisation As part o
Page 55 and 56: Figure 4‐2. Lift Distribution acc
Page 57 and 58: The next three figures show the lif
Page 59 and 60: 5 Results of the Monitoring Campaig
Page 61 and 62: the lift, but does not include addi
Page 63 and 64: Where, E standby Standby Energy use
Page 65 and 66: Figure 5‐4 shows a typical cycle
Page 67 and 68:
Figure 5‐6. Travel cycle consumpt
Page 69 and 70:
Figure 5‐9. Measured standby powe
Page 71 and 72:
Figure 5‐12. Annual Energy consum
Page 73 and 74:
Figure 5‐16. Annual Energy consum
Page 75 and 76:
Figure 5‐19. Annual electricity c
Page 77 and 78:
6.1.1 Determination of the average
Page 79 and 80:
Where, P mech E cycle η system h v
Page 81 and 82:
6.2. Electricity consumption of lif
Page 83 and 84:
6.3. Estimation of potential saving
Page 85 and 86:
The results show that overall savin
Page 87 and 88:
6.5. Estimation of Savings Potentia
Page 89 and 90:
Identification of stakeholders and
Page 91 and 92:
Table 7‐1. Categories of stakehol
Page 93 and 94:
esults were presented and discussed
Page 95 and 96:
We also asked which stakeholder inf
Page 97 and 98:
not rate an item. Reasons for non
Page 99 and 100:
Further barriers We asked responden
Page 101 and 102:
Raising awareness Setting a standar
Page 103 and 104:
Further topics This section address
Page 105 and 106:
The scope of the present study is o
Page 107 and 108:
Table 7‐4. Energy efficiency: Spe
Page 109 and 110:
10 Check system architecture Ropes
Page 111 and 112:
17 Avoid stalled motor door operato
Page 113 and 114:
24 Switch off other lift components
Page 115 and 116:
passenger arrives. However, an addi
show all

WP6-Brochure-E4 brochure - ELA European Lift Association.

Create successful ePaper yourself

Delete template?

Save as template?