WO2014174159A1

WO2014174159A1 - Device for supplying direct current for a set of led-based lighting devices used in industrial lighting and tertiary lighting

Info

Publication number: WO2014174159A1
Application number: PCT/FR2013/000112
Authority: WO
Inventors: Jacques Froidefond; Osvald Minghi
Original assignee: Societe D'etudes Et D'economies En Eclairage, Se3
Priority date: 2013-04-24
Filing date: 2013-04-24
Publication date: 2014-10-30

Abstract

The technical sector of the invention is that of a pooled power supply, distributing electrical energy as direct current to a set of lighting devices used in industrial lighting and tertiary lighting and implementing the technology of LEDS, without generating harmonics, or electromagnetic radiation, with a power factor almost equal to one and while minimizing energy consumption by lighting adapted to requirements.

Description

DC power supply device for a set of LED lighting devices used in industrial lighting and tertiary lighting

The field of the invention is that of the centralized DC power supply of a set of lighting devices used in industrial lighting and tertiary lighting using LED technology, this without generating harmonics or electromagnetic radiation, with a power factor of 1 and decreasing consumption.

Lighting is one of the latest technologies to be still largely analogically controlled. Especially in homes where the ON / OFF is the height of sophistication while each member of the household has ultra-sophisticated electronic equipment.

LEDs are to be replaced in their family: they are optoelectronic components of power whose evolution is logically similar to that of the microprocessors which follow the law of Moore. Indeed, LEDs double their luminous flux, every 18-24 months. Therefore, it is easy to conjecture as to the future performance of leds.

Lighting, too, needs to be placed in a broader context. Lighting is a function that meets a need: to see in places deprived of light.

As designers of products whose function is to "light up" using the technologies at their disposal, it is only logical that lighting products adopt the technological evolutions that are available at the time of their design. For several decades, a fundamental movement has been driving technology forward: the transition from analogue to digital. This passage was initiated by transistors in the 40-50s and continued with the evolution of content storage formats. As a result, lighting product technologies are moving along and are increasingly using discrete components that have become available, surface mounted or integrated.

Led lighting is therefore a solution for the future, promising significant savings in energy, but can also generate nuisance produced by poorly adapted food.

At a time of sustainable development, electricity consumption and respect for the environment are the terms that characterize light-emitting diodes (LEDs). A technology dating from the 60s, LEDs currently constitute a large and eclectic set whose applications depend on both the light output and the color of emission.

White LEDs of high power, appeared thanks to the research of S. Nakamura in the 90s, are currently in full swing for use in particular in lighting. The criteria that must be apprehended for the implementation of these LEDs are: the luminous flux, the luminous efficiency, the service life, the quality of the light, the conditions of power supply, the conditions of heat dissipation. One of the major advantages of the implementation of the power LEDs is their luminous efficiency. While the typical luminous efficiency of incandescent lamps is 15 Im / W, that of LEDs is of the order of 95 to 100 Im / W which brings them closer to fluorescent sources whose typical efficiency is close to 100 im / W. moreover, this efficiency continues to increase.

Since the emergence of power LEDs (> 0.25W) in the late 90s and especially white LEDs, optics in different areas has seen a dramatic evolution. Thus, the efficiency of these components, their dimensions and their modes of supply have made it possible to develop and / or improve lighting applications using previously old technologies (incandescent, high-pressure mercury discharges).

However, the available electricity network is an alternating network of variable frequency depending on the country, but 50 Hz in Europe.

In addition, the current is distributed in France under a nominal voltage of 230 V, with a tolerance of +/- 10%, ie from 207 to 253 V.

The electronics associated with these new components (LEDs) have also had to adapt and propose new solutions, in order to follow this strong growth, to allow the development of new optical solutions and above all, to preserve the optical performance of LEDs. by an optimized power mode.

Stabilized power supplies and other controllers provide either a fixed output voltage or a constant output current.

The LEDs must be current-driven, that is to say that the driving electronics of the LEDs must be able to fix the current flowing through them, regardless of the number of LEDs that are placed in series.

Manufacturers of LED lamps and tubes have developed various types of power supply to transform this AC current into direct current and thus be able to use their products directly in existing installations.

These devices have also been the subject of multiple patent filings, such as for example:

• FR 2919457: Electroluminescent diode supply device mainly RGB (LED);

EP 1411750: This patent describes a power supply system;

EP 1555860: This patent relates to DC power supply modules for a lighting device driving electrical equipment with a rectifier, with an electrical equipment module, mechanically connected. and electrically removably to the central unit:

EP 2110937: This patent relates to the manufacture of an AC-DC type isolation converter in which the input current from the network is converted to obtain a direct current;

EP 2107859: This patent relates to the control of lighting for which LEDs are used as lighting means. According to the invention, the transforming current of the supply network is converted into a direct current on a free oscillation blocking transformer;

EP 2079156: This patent relates to a DC power supply device;

EP 2079157: DC device for power supply;

EP 2278861: This patent relates to a system for controlling power devices for lighting means;

• WO 2011001369: This patent relates to a power supply circuit that includes an LLC converter stage for converting a DC voltage input into a DC voltage output;

WO 20 0002199: This patent relates to an LED lighting circuit in which a periodically varying AC power supply is applied and converted into a DC power supply and converted DC power supply;

WO 9750168: This patent relates to an apparatus (10) delivering to a network of light-emitting diodes (12) a direct current in regulated voltage;

• WO 2010134721: This patent relates to a multilayer power factor correction circuit (PFC).

The latter patent shows the problem generated by all the above mentioned devices whose function is to miniaturize the transformation of an AC power supply to direct current.

The adopted electronic devices have the disadvantage, in addition to the multiplication of costs and components used, to be generators of harmonics, electromagnetic radiation and have a bad power factor that must be compensated by capacitors ( as for the neon tubes, whether they are with ferromagnetic or electronic ballasts).

The present invention proposes to adapt the device that is the subject of the patents cited below, to supply DC power to a set of LED devices:

• Method and device for supplying discharge lamps

Publication EP 0970593 (A1) - 2000-01-12 Priority Date: 1997-03-27

• System and apparatus for supplying discharge lamps of a lighting network Publication FR 2761564 (A1) - 1998-10-02

Publication FR 2761564 (B1) - 2001-07-27 Priority Date: 997-03-27

• Protection device against overloads and circuit currents of a DC power supply

Publication FR 2941825 (A1) - 2010-08-06 Priority Date: 2009-01-30

• Apparatus contributing to the safety of people and the preservation of heritage in a power network supplying direct current and galvanically isolated especially in public lighting

• Publication FR 2908242 (A1) - 2008-05-09 Priority Date: 2006-11-03

The object of this process mentioned in the aforementioned patents is to supply a group of discharge lamps for public lighting, situated downstream of a connection point to the 50 Hz energy network, by a unit. Central which isolates it electrically from 50 Hz and which transmits to the generators associated with the lamps, a constant power in direct current whose value is independent of the fluctuations of the tension of the network 50 Hz, this value being variable according to a setpoint. The Central Unit takes from the network with a low harmonic current phase sinusoidal current (patent FR 2761564).

The aim of the invention is to propose a solution that avoids the electrical stresses induced by the solutions usually used by directly supplying at 50 Hz the sets of LED tubes intended to replace the fluorescent tubes by accomplishing the following objectives:

• Reduce installation costs,

• Reduce operating costs,

• Remove harmonics,

· Avoid electromagnetic radiation

• Get a power factor close to 1.

• Reduce the number of electronic components implemented by pooling the production functions of the DC current naturally planned to circulate in the LEDs and necessary to achieve the electronic control and control functions.

• Realize a power supply stabilizing the operation of a set of leds put in series in a LED tube, then in parallel with each other and having finally a characteristic [U-1] compatible with that delivered by the central unit. Indeed, the hyperbole is certainly the most suitable [U] characteristic for a stable and controlled operation of a set of LEDs placed in series then in parallel and having statistically different [UI] characteristics whose variance depends on the method of manufacturing used.

• Use the adjustable power level of the central unit to adjust simple the level of illumination of all LED tubes in accordance with the needs knowing the luminous flux has for image a power.

The lighting market for LED devices made up of department stores and their associated warehouses is divided into two parts:

· New installations,

• Replacement of existing lighting devices (relamping).

For new installations, the process saves money on the manufacture of LED devices by removing the built-in AC-DC converter.

For relamping, the method can make it possible to avoid disassembly of the strips for the suppression of ballasts and compensation capacitors. However, with electromagnetic ballasts whose lifetime is significantly lower than that of leds, this may generate subsequent interventions to eliminate the source of failure, the ballast may cause a circuit break.

To illustrate the interest of the process, here are the results of measurements that we carried out on T8 tubes of length 120 cm, respectively neon, then leds in supply with the 50 Hz AC network, then with our method:

• E1: 1 120 cm fluorescent tube 50 Hz AC power supply (with compensation capacitor and electromagnetic ballast)

• E2: 1 T8 120 cm AC power 50 Hz leds

· E3: 1 T8 120cm DC power supply leds

We aknowledge :

That the passage of neons in leds generates a saving of 50% of the apparent power;

That the DC power supply (using a constant power) LED tube generates an additional saving of 80%, an economy of 87% compared to neon tubes;

That the power factor is 1;

That there are almost no harmonics (they are caused by the central AC / DC transformation device and less than 5%.

In addition, we have all the advantages developed in the patents filed: • Short circuit protection;

• Galvanic isolation;

• Security of property and people;

• Possibility of dimming.

· Cos φ close to 1

In the context of a new installation, the power being reduced, this allows to realize significant savings in sizing cables, and more generally all the equipment of the installation from the transformer.

The disappearance of the harmonics also avoids over sizing the neutral wire.

The device is intended for lighting by LED tubes of the stores, generally classified ERP, it therefore provides an inverter allowing in case of electronic failure a direct supply in 50 Hz of all the leds tubes concerned: it eliminates the central unit of the supply circuits.

A particular embodiment of the invention is shown in FIGS. 1 and 2.

Figure 1 shows an embodiment for a single-phase AC power supply. It consists of a control unit (2) called: pilot module and a power unit (1) called power module.

It is thus possible according to the configuration of the installation, to control several power modules (1) with a single pilot module (2).

The device is inserted directly at the output of the existing control cabinet at the power supply outlet of the lamp or tube circuits.

The industrial application of the invention is its use for the supply of lighting of medium and large surfaces, whether industrial or commercial, intended to be equipped with a lighting device generating significant energy savings , and therefore CO2.

FIG. 2 represents the operation by means of an inverter (4), making it possible to feed directly via the 50 Hz network all the devices to LEDs, which are then no longer powered by the central unit.

The present invention relates to a device located at the point of connection to the source of electrical energy distributed by the 50 or 60 Hz electrical network called "central unit" taking, at the 50 or 60 Hz network, a sinusoidal current in phase to feed through a dc source, a set of LED devices galvanically isolated from the 50 Hz electrical power source, supplying and injecting a constant DC power, independent of the 50 Hz mains voltage and adjustable according to one or more setpoints. Each central unit comprising a control module called pilot module, associated with at least one power module corresponding to a power injected into all of the LED devices, included and adjustable between a hundred watts and at least 2000 W, the power modules can according to the nominal power to provide be coupled in parallel to the receiver assembly consisting of LED devices, this set being able to must be connected directly to the 50 Hz network.

The power module (1) comprises

• A diode bridge in the case of a 50 or 60 Hz energy network.

At least one rectified voltage converter or DC voltage to a DC voltage, using a transformer whose primary is connected to the rectified or continuous voltage for a time T1 depending on the operating setpoint C, the connection being established by a switch of power then interrupted for a time T2 + ts during which the energy accumulated in the primary of the transformer is transmitted to the secondary thereof through a rectifying diode supplying a storage capacitor and then all the devices to leds in direct current . The conversion process used is that of the flyback, the transformer of which can cause leaks and losses when switching the switch.

• Known ways to recover as much as possible leaks and switching losses.

Power supply electronics of the power card comprising a filter stage connected to a phase line and a neutral line.

The pilot module (2) see Figure 1 comprises:

• Means for creating the orders addressed to the control triggers of the electronic power switches corresponding to the cycles T1 + (T2 + ts), see FIG. 3, T1 being the closing and connecting time of the primary on the energy network, T2 the discharge time of the secondary and ts the rest period for zero-current switching.

• An instruction block and correction of it depending on the voltage of the energy network transmitting to each power module the operating setpoint and allowing it to develop the value of T1 common to each power module.

The pilot module receives the state of the DC voltage of the secondary: value of the voltage higher than an adjustable value up to 250V or that corresponding to a short circuit, it triggers in this case actions giving T1 the value 0 when the security of the means used imposes it (see device 3 figure 1).

Claims

1 - Device, located at the point of connection to the source of electrical energy distributed by the 50 or 60 Hz electrical network. Called "central unit" taking, at the 50 or 60 Hz network, a sinusoidal current in phase to supply DC power , a set of LED devices galvanically isolated from the electrical power source 50 Hz, supplying and injecting a constant DC power, independent of the effective voltage of the 50 Hz network and adjustable according to one or more setpoints, characterized in that each central unit comprises a control module called pilot module, associated with at least one power module corresponding to a power input into the set of LED devices, included and adjustable between a hundred watts and at least 2000 W, the power modules that can, depending on the nominal power to be supplied, be coupled in parallel to the receiver assembly constituted by the devices to be leds, each leds device of this set may or may not be equipped with its power 50hz often called driver or controller

2 - Device according to claim 1, characterized in that the power module (1) comprises:

• A diode bridge in the case of a 50 or 60 Hz energy network.

· At least one rectified voltage converter or DC voltage to a DC voltage using a transformer whose primary is connected to the rectified or continuous voltage for a time T1 depending on the operating setpoint C, the connection being established by a power switch and then interrupted for a time T2 + ts during which the energy accumulated in the primary of the transformer is transmitted to the secondary thereof through a rectifying diode supplying a storage capacitor and all the devices to leds in direct current. Means for recovering as much as possible leaks and switching losses.

3 - Device according to claims 1 and 2, characterized in that the pilot module (2) comprises:

• Means for creating orders addressed to power electronic switch control triggers

A set and correction block of the latter as a function of the voltage of the energy network transmitting to each power module the operating setpoint and allowing it to develop the T1 value common to each power module. -Dispositif according to claims 1, 2 and 3 characterized in that it immediately imposes on T1 the value 0, if the value of the DC voltage of the secondary exceeds an adjustable setpoint value less than 250V, or if the secondary is short circuit. Device according to claims 1, 2, 3 and 4, providing to the set of LED devices, connected in series and in parallel with a hyperbolic voltage current characteristic ensuring a very high stability of operation to the generator set receivers, the devices to leds being or not equipped with their usual device of alimentation.50 or 60 hz

Device according to claims 1, 2, 3 and 4, and 5 for injecting into

the set of devices with adjustable DC power allowing the centralized variation of their illuminate to adjust the level of it to the needs required especially when the LED devices are not equipped with their usual power supply device. or 60 hz Device according to claims 1, 2, 3 and 4, 5 and 6 for limiting, in the event of non-operation of a number of LED devices, the DC power supply voltage, of the set of LED devices still functional, at an adjustable value compatible with their proper operation. Device according to claims 1, 2, 3 and 4, 5, 6 and 7 which achieves the pooling of AC / DC conversion functions, protection, illumination variation LED devices powered by the device, making unnecessary your power supplies 50hz of each leds device and greatly reducing the losses of each of the leds devices thus significantly prolonging their lifetime