Digital Addressable Lighting Interface Research Articles

Reduction of lighting power consumption through lighting control using the KNX/digital addressable lighting interface protocol in liquefied natural gas carrier accommodation mock-up

Lighting in ships is the main energy consumer in the overall power system and is closely associated with the creation of visual comfort and a safe work environment for the crew. A convergence point between the energy efficiency of ship lighting and a safe work environment for the crew can be achieved in various ways. This study applied the KNX and Digital Addressable Lighting Interface (DALI) systems to a mega-ship. A mock-up identical to an accommodation unit in an actual Liquefied Natural Gas Carrier in construction was developed, where the lighting for ships was installed and the KNX/DALI protocol, and occupancy sensors were applied as the lighting control system. The measurement of the 24 h power consumption with a conventional lighting arrangement design and the KNX/DALI system indicated that the lighting power consumption decreased from 12,935.2 to 2830.3 W h, implying a ≥80% reduction. This lighting solution involves control based on the traffic line of the crew at work, which plays a key role in enhancing the energy efficiency of the ship, promoting a safe work environment and visual comfort for the crew, and maximizing integration with other digital systems of the ship.

DALI Bridge FPGA-Based Implementation in a Wireless Sensor Node for IoT Street Lighting Applications

Smart lighting systems based on the Digital Addressable Lighting Interface (DALI) protocol are the most suitable for street lighting systems, allowing digital lighting control operations. Unfortunately, the microcontrollers, which are commonly used in the Wireless Sensor Network nodes to control the lamps, do not implement this protocol. The DALI protocol implemented by software in the microcontroller consumes hardware resources (timers), processing time and requires a precise temporal analysis of the application, due to the strict bit times and the Manchester coding that it uses. In this work, the design of a bridge is proposed to free the microcontroller from the implementation of the DALI protocol. The novelty of this work is the implementation of the DALI Bridge in a low-cost Field-Programmable Gate Array (FPGA) with low power consumption. The bridge has been described in the hardware description language following the 1076-93 and 1076.3-97 standards, to guarantee its portability. The results of the synthesis show that a minimum amount of logical and routing resources is used, that the power consumption is in the order of tens of mW, that it has a very small latency time and that it supports a high operating frequency, which allows adding new functions. Its operation is verified by implementing a wireless sensor node using an FPGA of the Lattice Semiconductor iCE40 family.

DALI LED Driver Control System for Lighting Operations Based on Raspberry Pi and Kernel Modules

Light emitting diodes (LEDs) as an efficient low-consumption lighting technology are being used increasingly in many applications. The move to LED lighting is also changing the way the lighting control systems are designed. Currently, most electronic ballasts and other digital lighting devices implement the Digital Addressable Lighting Interface (DALI) standard. This paper presents a low-cost, low-power effective DALI LED driver controller, based on open-source Raspberry Pi3 microcontroller prototyping platform. The control software is developed as a Linux kernel module under UBUNTU 18.04.2 LTS patched with PREEMPT_RT (Preemptive Real-time) for real-time processing. This dynamically loaded kernel module performs all the processing, communication and control operations of the Raspberry Pi3-based DALI controller with the DALI LED driver and LED luminaire. Software applications written in C and Python were developed for performance testing purposes. The experimental results showed that the proposed system could efficiently and effectively manage DALI LED drivers and perform lighting operations (e.g. dimming). The system can be used for a variety of purposes from personal lighting control needs and experimental research in control of electronic ballasts and other control gears, devices and sensors, to advanced requirements in professional buildings, including energy management, lighting maintenance and usage.

Investigation of an integrated automated blinds and dimmable lighting system for tropical climate in a rotatable testbed facility

Performance of automated blinds and auto-dimming lighting system in providing lighting energy savings and occupant visual comfort was studied in a rotatable testbed facility located in tropical Singapore. The automated Venetian blinds system, consisting of a daylight-redirecting top portion and a glare-controlling bottom portion, was controlled by an in-house developed control algorithm designed specifically for tropical climate of Singapore to introduce maximum daylight while minimising Daylight Glare Probability (DGP). The auto-dimming lighting system used Digital Addressable Lighting Interface (DALI) controller to control T5 fluorescent and LED luminaries. Energy consumption by the lighting system, working plane illumination distribution and DGP were monitored by a network of sensors and high-dynamic range (HDR) camera systems. Compared to non-dimmable T5 lighting, LED lamps provided about 24% of lighting energy savings. Auto-dimming technology showed about 46% lighting energy savings. LED lamps coupled with auto-dimming showed around 80% lighting energy savings. Without window blinds, the working plane illuminance exceeded the recommended 3000 lx level during certain time of the day and DGP exceeded 0.35. The automated blinds effectively eliminated glare discomfort, and with the automated blinds working in conjunction with the auto-dimming, significant lighting energy savings was achieved without compromising the illuminance level at the working plane. 75% of lighting energy savings was achieved for North orientation and 63% for East orientation. Façade orientation was found to have a significant impact on the lighting energy savings potential, with the North orientation achieving higher daylight savings due to higher daylight redirection possibility throughout the day. The lighting energy savings potential is higher for clearer sky conditions due to higher daylight availability. Implementation of daylight re-directing shading system has significant lighting energy savings in the tropics. These lighting energy savings can be captured by deploying an auto-dimming system. With careful design of the system and control algorithm, the lighting energy savings can be achieved while maintaining good visual comfort.

위상각 제어에 의한 DALI 프로토콜 기반의 LED조명 제어방법

Generally, the phase control dimmer has been widely used due to simple interface and easy handling. However, the electrical characteristics are not good for the method in which the phase control dimmer cuts the input voltage. This paper has researched about DALI(Digital Addressable Lighting Interface) controller, that is the digital lighting control method, and implemented DALI protocol satisfied with the IEC-62386 standard. In addition, the existing phase control dimmer was used as the controller of DALI and not only individual control but also group control was possible. And the performance was proved to be good by applying our theory to 30[W] LED lighting control system.

Building lighting automation through the integration of DALI with wireless sensor networks

This paper focuses on the integration of Digital Addressable Lighting Interface (DALI) devices in wireless sensor networks. Since different manufacturers usually deal with one aspect of building automation - e.g. heating ventilation and air conditioning, lighting control, different kinds of alarms, etc. - final building automation system has different subsystems which are finally taken to an integrated building management system. The cost of this process is consequently increased due to additional hardware investment. Our main purpose is to provide the end consumer with an economical fully centralized system in which home appliances are managed by an IEEE 802.15.4-based wireless sensor network. Not only is it necessary to focus on the initial investment, but maintenance and energy consumption costs must also be considered. This paper explains the developed system along with a brief introduction to usual building automation protocols. Finally it presents future work in this field.

Low-rate wireless personal area networks applied to street lighting

This paper focuses on the development of an energy-efficient street lighting remote management system making use of low-rate wireless personal area networks and the digital addressable lighting interface (DALI) protocol to get the bidirectional communication necessary for checking lamp parameters like lamp status, current level, etc. Because of the fact that two-thirds of the installed street lighting systems use old and inefficient technologies, there exists a huge potential to renew street lighting and save energy consumption. The proposed system uses the DALI protocol in street lighting, increasing the maximum number of ballasts that can be controlled with DALI – originally it can only drive up to 64 ballasts. Some aspects of the wireless communication system and experimental measurements are presented and discussed.

The New York Times Headquarters daylighting mockup: Monitored performance of the daylighting control system

A 9-month monitored field study of the performance of automated roller shades and daylighting controls was conducted in a 401 m 2 unoccupied, furnished daylighting mockup. The mockup mimicked the southwest corner of a new 110 km 2 commercial building in New York, New York, where The New York Times will be the major tenant. This paper focuses on evaluating the performance of two daylighting control systems installed in separate areas of an open plan office with 1.2-m high workstation partitions: (1) Area A had 0–10 V dimmable ballasts with an open-loop proportional control system and an automated shade controlled to reduce window glare and increase daylight, and (2) Area B had digital addressable lighting interface (DALI) ballasts with a closed-loop integral reset control system and an automated shade controlled to block direct sun. Daylighting control system performance and lighting energy use were monitored. The daylighting control systems demonstrated very reliable performance after they were commissioned properly. Work plane illuminance levels were maintained above 90% of the maximum fluorescent illuminance level for 99.9 ± 0.5% and 97.9 ± 6.1% of the day on average over the monitored period, respectively, in Areas A and B. Daily lighting energy use savings were significant in both Areas over the equinox-to-equinox period compared to a non-daylit reference case. At 3.35 m from the window, 30% average savings were achieved with a sidelit west-facing condition in Area A while 50–60% were achieved with a bilateral daylit south-facing condition in Area B. At 4.57–9.14 m from the window, 5–10% and 25–40% savings were achieved in Areas A and B, respectively. Average savings for the 7-m deep dimming zone were 20–23% and 52–59% for Areas A and B, respectively, depending on the lighting schedule. The large savings and good reliability can be attributed to the automatic management of the interior shades. The DALI-based system exhibited faulty behavior that remains unexplained, but operational errors are expected to be resolved as DALI products reach full maturity. The building owner received very competitive bids ($30–75 US/DALI ballast) and was able to justify use of the daylighting control system based on operational cost savings and increased amenity. Additional energy savings due to reduced solar and lighting heat gains were not quantified but will add to the total operational cost savings.

A Novel Lighting Control System Integrating High Dynamic Range Imaging and DALI

Conventional photosensor-based lighting control systems rely on an integrated photosensor signal that senses the overall illuminance within a space and is calibrated to address performance at a specific critical task point. All surfaces within the field of view (FOV) of the photosensor influence this signal. This paper presents a new method of lighting control that applies an inexpensive image sensor as the light sensing device in conjunction with a computer graphics technique known as High Dynamic Range imaging. A wide range of lighting levels can be evaluated using this technique, and a single sensor is capable of estimating the illuminance levels simultaneously at multiple locations on the work plane. This paper describes a calibration procedure to derive space illuminance information from the images during system operation. It also provides an algorithm to control individual luminaires to achieve different target illuminances at different points on the work plane. The solution takes full advantage of the powerful features of digital technologies, including both digital imaging and Digital Addressable Lighting Interface (DALI) ballasts. This novel solution, described as CamSensor in this paper, is a proof-of-concept for the application of High Dynamic Range imaging in the field of lighting control.