Current regulator device for luminaire device and method for operating luminaire device
By using a DC voltage source and current regulator in a laser diode device, setting up upper and lower voltage levels and current measurement devices, and generating transformer control signals, the problem of low efficiency in existing laser diode devices is solved, achieving efficient and dynamic current control, and reducing switching losses and flickering effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2026-03-27
AI Technical Summary
Existing technologies struggle to efficiently control laser diode devices, especially at low power levels where efficiency is low and they are susceptible to flicker effects.
A current regulator device with a DC voltage source is used. By setting the upper and lower voltage levels and current measuring devices, a transformer control signal is generated to adjust the current without measuring the voltage. A filter composed of a transformer and an inductor is used to reduce switching losses, achieving high dynamics and high efficiency.
It improves the efficiency and dynamics of laser diode devices, reduces switching losses, lowers control overhead, prevents flickering, and maintains good performance at low power.
Smart Images
Figure CN121753477A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a current regulator device for lighting equipment, particularly laser diode equipment, having a DC voltage source providing upper and lower voltage levels different from ground potential. Furthermore, this invention relates to a method for operating lighting equipment, particularly laser diode equipment. Background Technology
[0002] EP 2 667 687 A1 discloses an operating control device for operating a luminaire, which specifically has light-emitting diodes connected in series. The operating control device includes a transformer controlled by a switching signal from the control device, which provides an output current at its output. Both the luminaire and an output capacitor are connected to this output. A control switch is controlled by the control device via a pulse-width modulation (PWM) control signal and is positioned in series with the luminaire. Before the control switch closes, the output capacitor is charged during a charging period, and the output current increases. This current rise phase occurs before the control switch closes, thus preventing flickering of the luminaire even with a small pulse width of the control signal.
[0003] If laser diodes are to be manipulated as lighting fixtures, this must be done with high dynamics and high efficiency. Summary of the Invention
[0004] Therefore, the object of the present invention is to provide a control concept for lighting equipment, particularly laser diode equipment.
[0005] According to the invention, this objective is achieved by a current regulator device for lighting equipment, particularly laser diode equipment, the current regulator device having a DC voltage source providing an upper voltage level and a lower voltage level different from ground potential, the current regulator device having at least one current regulator connected to the DC voltage source, the at least one current regulator having at least one transformer connected to the upper voltage level and the lower voltage level, wherein a current measuring device for sensing the output current of a converter is provided, the current measuring device being connected to a control device that generates an operating signal for the transformer.
[0006] Because two voltage levels are set, the current regulator does not need to operate over the entire voltage range between 0 volts and the upper voltage level. Because a lower voltage level is set, a smaller voltage range needs to be covered, thus improving efficiency. This results in fewer switching losses in the transformer, allowing it to operate at higher frequencies and be dynamically designed, while achieving higher efficiency for the entire device. The device according to the invention enables the dynamism of the analog drivers, allowing these drivers to be omitted. In particular, the current regulator device according to the invention still maintains good efficiency even when the lighting equipment operates at lower power, for example, only 50% of the maximum power.
[0007] The DC voltage source is preferably configured to generate two voltage levels from the grid voltage. This can be achieved, for example, by using a flyback transformer or a resonant transformer in combination with a rectifier.
[0008] According to the present invention, the current of the lighting equipment is specifically configured to be adjusted only via a current regulator. In particular, voltage measurement is not required. Furthermore, no switch is provided, or a switch is not required, to turn the lighting equipment on and off.
[0009] The transformer may have at least one switching element, which is controlled by a control device. According to the invention, a clock current regulator concept with high dynamics and high efficiency is thus provided. By appropriately controlling the switching element according to the measured current, the current for the lighting equipment can be generated in a particularly reliable and dynamic manner. The current regulator device according to the invention operates according to the invention without measuring the voltage. In particular, the voltage is not adjusted, but only the current supplying power to the lighting equipment is adjusted.
[0010] The lower voltage level can be at least 65%, preferably at least 70%, of the upper voltage level. This allows for adjustment of a small voltage range that must be covered by the transformer. The lower voltage level can be adjusted, particularly according to the lighting equipment to be operated. The lower voltage level is preferably slightly lower than the threshold voltage required to turn on the laser diode.
[0011] A particular advantage arises when the current regulator is arranged in a floating configuration. Therefore, the current regulator is independent of ground potential. This approach enables improved EMC performance and prevents the regulator's operation from being affected by unexpected ground faults. For example, a ground fault can be detected via additional voltage measurements and transmitted to the user.
[0012] When a transformer is designed as a step-down converter, a particularly simple implementation of the transformer is obtained. Alternatively, it is conceivable to design the transformer as a step-up converter or a flyback transformer.
[0013] To provide a suitable, low-ripple current, it is advantageous if the current regulator includes an inductor. Preferably, the inductor is part of a low-pass filter. According to the invention, a low-pass filter or an EMC filter can therefore be connected downstream of the transformer.
[0014] According to one embodiment of the invention, the current regulator can be configured to have multiple transformers connected in parallel, which are operated in a clock-shifted manner. This measure can further increase dynamics and reduce ripple.
[0015] Furthermore, it is conceivable that the current regulator device has multiple current regulators connected in parallel, which are controlled in a clock-skewed manner. The current regulator device can control different lighting devices, particularly laser diode strings. This measure can also reduce the ripple of laser devices with multiple such laser diode strings.
[0016] The scope of this invention also includes a method for operating lighting equipment, particularly laser diode equipment, the method comprising the following steps: - Provide a first DC voltage level and a second DC voltage level. - Sensing the current at the output of the current regulator. - Based on the measured current, a control signal is generated to control the transformer connected to the current regulator at the first voltage level and the second voltage level, so as to generate a predetermined current through the current regulator.
[0017] Therefore, the current used in lighting equipment is adjusted through current modulation. The current is generated solely by the current regulator, without the need for voltage measurement. Since a transformer is used with two DC voltage levels connected to it, only a small voltage difference needs to be overcome. This reduces potential switching losses at the switching elements in the transformer. Furthermore, a high degree of dynamism is possible.
[0018] Specifically, the duty cycle of the control signal can be adjusted based on the measured current. This allows for adjustment of the output current intensity of the current regulator. Furthermore, this eliminates the need for a switch connected in series with the lighting fixture to turn it on and off. Compared to existing technologies, this significantly reduces control and circuit overhead.
[0019] The control signal can preferably be generated at a frequency in the range of 500 kHz to 2 MHz, particularly 1 MHz. Therefore, the method can be implemented at very high clock frequencies, especially significantly higher clock frequencies than those in the prior art.
[0020] To reduce ripple, multiple transformers can be controlled using clock-shifted control signals. Here, all transformers can be controlled using signals of the same frequency. Attached Figure Description
[0021] Further features and advantages of the invention will become apparent from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings, which illustrate essential details of the invention. Features shown herein are not necessarily drawn to scale, but are shown in a manner that makes the particular features according to the invention clearly visible. In variations of the invention, each feature may be implemented individually or as a plurality in any combination.
[0022] The schematic diagram illustrates exemplary embodiments of the present invention, and the exemplary embodiments are described in more detail in the following description.
[0023] In the attached diagram: Figure 1 A first embodiment of the current regulator device is shown; and Figure 2 A second embodiment of the current regulator device is shown. Detailed Implementation
[0024] Figure 1 A current regulator device 10 for a lighting device 12 is shown, wherein additional lighting devices 14, 16 are also shown in the illustrated exemplary embodiment. In the illustrated exemplary embodiment, lighting devices 12, 14, 16 have a series connection of a laser diode 18. Other connections of the laser diode 18 are also conceivable.
[0025] DC voltage source 20 provides an upper voltage level 22 and a lower voltage level 24. The lower voltage level 24 is different from ground potential. Figure 1 In the exemplary embodiment shown, a plurality of current regulators 26, 28, and 30 are provided, which are connected in parallel to the upper voltage level 22 and the lower voltage level 24. One of the lighting devices 12, 14, and 16 is connected to the output of each of the current regulators 26, 28, and 30.
[0026] Each current regulator 26, 28, 30 has a transformer 40, 42, 44, which, in an exemplary embodiment, are designed as a step-down converter. Each transformer 40, 42, 44 has two switching elements S1, S2. Inductors 46, 48, 50 are connected between the switching elements S1, S2, respectively. The inductors 46, 48, 50 may be components of a low-pass filter. Current measuring devices 52, 54, 56 are arranged at the outputs of the inductors, and therefore at the outputs of the current regulators 26, 28, 30, respectively. These current measuring devices 52, 54, 56 each sense the current supplied by the current regulators 26, 28, 30 and feed the current to the control device 58. Taking into account the measured current, the control device 58 generates a control signal 60 of a predetermined frequency for the transformers 40, 42, 44. Here, the switching elements S1, S2 of the different transformers 40, 42, 44 can be controlled in a clock-shifted manner.
[0027] The current generated by the corresponding current regulators 26, 28, and 30 can be adjusted by adjusting the duty cycle of the control signal 60, which can have a frequency of 1 MHz. Therefore, there is no need to install additional switches connected in series with the lighting devices 12, 14, and 16. Furthermore, there is no need to measure the voltage and to take that voltage into account when generating the control signal. It can also be seen that the current regulators 26, 28, and 30 are arranged in a floating configuration. Only the voltage difference between the upper voltage level 22 and the lower voltage level 24 corresponding to voltage U2 needs to be switched via transformers 40, 42, and 44. Therefore, the concept according to the invention has high dynamics and high efficiency.
[0028] According to Figure 2 In one embodiment of the current regulator device 10a, a DC voltage source 20 is also provided, which provides an upper voltage level 22 and a lower voltage level 24. In this embodiment, the current regulator 26a assigned to the lighting device 12 has multiple transformers 40, 40a, and 40b, which are connected in parallel to the upper voltage level 22 and the lower voltage level 24. Therefore, inductors 46, 46a, and 46b are connected downstream of the transformers 40, 40a, and 40b. Current measuring devices 52, 52a, and 52b are respectively provided at the outputs of the inductors 46, 46a, and 46b. Current measuring devices 52, 52a, and 52b sense the output current at the corresponding inductors 46, 46a, and 46b. Specifically, the current measuring devices 52, 52a, and 52b... Figure 1The current measuring devices 52, 54, and 56 described herein are arranged between inductors 46, 48, 50, 46, 46a, and 46b and lighting fixtures 12, 14, and 16. The sensed current is considered by control device 58 to generate control signals 60 for transformers 40, 40a, and 40b. Here, the switching elements S1 and S2 of each transformer 40, 40a, and 40b are controlled in a clock-shifted manner to reduce ripple.
Claims
1. A current regulator device (10, 10a) for lighting equipment (12, 14, 16), particularly for laser diode equipment, the current regulator device having a DC voltage source (20) providing an upper voltage level and a lower voltage level (22, 24) different from ground potential, characterized in that... At least one current regulator (26, 28, 30, 26a) is connected to the DC voltage source (20), the at least one current regulator having at least one transformer (40, 42, 44, 40a, 40b), the at least one transformer being connected to the upper voltage level and the lower voltage level (22, 24), wherein a current measuring device (52, 54, 56, 52a, 52b) is provided for sensing the output current of the current regulator (26, 28, 30, 26a), the current measuring device being connected to a control device (58), the control device generating a control signal (60) for the transformer (40, 42, 44, 40a, 40b).
2. The current regulator device according to claim 1, characterized in that, The transformers (40, 42, 44, 40a, 40b) have at least one switching element (S1, S2) which is operated by the control device (58).
3. The current regulator device according to any one of the preceding claims, characterized in that, The lower voltage level (24) is at least 65%, preferably at least 70%, of the upper voltage level (22).
4. The current regulator device according to any one of the preceding claims, characterized in that, The current regulators (26, 28, 30, 26a) are arranged in a floating configuration.
5. The current regulator device according to any one of the preceding claims, characterized in that, The transformers (40, 42, 44, 40a, 40b) are designed as step-down converters.
6. The current regulator device according to any one of the preceding claims, characterized in that, The current regulators (26, 28, 30, 26a) have inductors (46, 48, 50, 46a, 46b), which are preferably components of a low-pass filter.
7. The current regulator device according to any one of the preceding claims, characterized in that, The current regulator (26a) has multiple transformers (40, 40a, 40b) connected in parallel, which are operated in a clock-shifted manner.
8. The current regulator device according to any one of the preceding claims, characterized in that, The current regulator device (10) has a plurality of current regulators (26, 28, 30) connected in parallel, which are operated in a clock-off manner.
9. A method for operating lighting equipment (12, 14, 16), particularly laser diode equipment, the method comprising the following steps: - Provides a first DC voltage level and a second DC voltage level (22, 24). - Current at the output of the sensing current regulator (26, 28, 30, 26a) - Based on the measured current, a control signal (60) is generated to control the transformers (40, 42, 44, 40a, 40b) of the current regulator (26, 28, 30, 26a) connected to the first voltage level and the second voltage level (22, 24) to generate a predetermined current through the current regulator (26, 28, 30, 26a).
10. The method according to claim 9, characterized in that, The duty cycle of the control signal (60) is adjusted according to the measured current.
11. The method according to claim 9 or 10, characterized in that, The control signal (60) is generated at a frequency in the range of 500 kHz to 2 MHz, preferably 1 MHz.
12. The method according to any one of the preceding claims, characterized in that, Multiple transformers (40, 42, 44, 40a, 40b) are controlled by a clock-biased control signal (60).