CN114205970A - Driving circuit - Google Patents
Driving circuit Download PDFInfo
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- CN114205970A CN114205970A CN202111517604.XA CN202111517604A CN114205970A CN 114205970 A CN114205970 A CN 114205970A CN 202111517604 A CN202111517604 A CN 202111517604A CN 114205970 A CN114205970 A CN 114205970A
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
Abstract
The invention discloses a driving circuit which comprises a sampling module, a control module and a load module, wherein the load module is connected with M lamp beads in a lighting branch in parallel, which is equivalent to that M lamp beads are connected with a load in parallel. In the dimming process, the working parameters and the target parameters collected by the control module generate control signals to adjust the equivalent impedance of the load module, so that the equivalent impedance of the M lamp beads connected with the load module in parallel is changed, and the working parameters of other lamp beads in the lighting branch except the M lamp beads are stabilized at the target parameters. In this application, need not control the power of the higher voltage of constant voltage source output, and then reduce the loss on the circuit, and can stabilize the working parameter of lamp pearl at the target parameter, realize the closed loop regulation to the lamp pearl, in addition, load module in this application includes a plurality of lamp pearls, is used for the energy for independent lamp pearl power supply to make and realize illumination or other functions, improved the utilization ratio of energy.
Description
Technical Field
The present invention relates to the field of lighting, and in particular, to a driving circuit.
Background
Referring to fig. 1, fig. 1 is a block diagram illustrating a lighting system in the prior art. The lighting system comprises a constant voltage source and a plurality of lighting branches, each lighting branch comprises a plurality of lamp beads, the constant voltage source outputs constant voltage to supply power for the lighting branches, and at the moment, the output voltage of the constant voltage source needs to be controlled to be greater than the voltage of all the lighting branches, so that the lamp beads in each lighting branch can normally emit light.
However, when the lighting system is used for lighting plants, for example, when the lighting system is applied to indoor lighting of a plant factory or supplementary lighting of plants, all the lamp beads in each lighting branch form one lamp, and since the plant cultivation areas for lighting each lamp are different, when the same constant voltage source is used for supplying power, the power supply line between the constant voltage source and the lamp may be longer, the loss on the power supply line is increased along with the increase of the distance, so that the lamp farther from the constant voltage source is caused, and the obtained voltage is also reduced. However, when the lamp is configured, the lamp is configured in an ideal state, that is, the voltage of the configured lamp is matched with the output voltage of the constant voltage source. Therefore, in actual operation, the lamp farther from the constant voltage source may have a voltage larger than the voltage supplied to the lamp by the constant voltage source, so that the operating current of the lamp is smaller than the rated value, and the brightness of the lamp cannot meet the expectation. However, in the prior art, in order to ensure that the operating current of the lamp far from the constant voltage source reaches the rated value, the output voltage of the constant voltage source is increased, but by using this method, the loss on the power supply line is further increased.
Disclosure of Invention
The invention aims to provide a driving circuit which does not need to control a constant voltage source to output a power supply with higher voltage so as to reduce the loss on a circuit, can stabilize the working parameters of lamp beads at target parameters and realize closed-loop regulation of the lamp beads.
In order to solve the technical problem, the invention provides a driving circuit, which is applied to a lighting system, wherein the lighting system comprises a constant voltage source and a plurality of lighting branches, the positive output end of the constant voltage source is connected with the positive end of each lighting branch, the negative output end of the constant voltage source is connected with the negative end of each lighting branch, each lighting branch comprises N beads, a driving circuit is arranged on at least one lighting branch, the driving circuit comprises a sampling module, a control module and a load module, and the load module comprises a plurality of beads;
the first end of the load module is connected with one end of M lamp beads in the N lamp beads, the second end of the load module is connected with the other end of the M lamp beads, the output end of the sampling module is connected with the input end of the control module, the output end of the control module is connected with the control end of the load module, N & gtM & gt is larger than or equal to 1, and N and M are integers;
the sampling module is used for sampling the working parameters of the lamp beads except for the M lamp beads in the illumination branch circuit connected with the sampling module to obtain sampling parameters;
the control module is used for adjusting the equivalent impedance of the load module based on the sampling parameter and a target parameter so as to enable the working parameter to be stabilized at the target parameter;
the load module is used for changing the equivalent impedance of the load module according to the signal of the control end of the load module to obtain electric energy, and the electric energy is supplied to the plurality of lamp beads included in the load module to enable the lamp beads to emit light.
Preferably, the operating parameter is operating current;
the sampling module is specifically used for sampling the working currents of the lamp beads, except M lamp beads, in the illumination branch circuit connected with the sampling module, so as to obtain the sampling currents.
Preferably, when the working parameter is working voltage;
the sampling module is specifically used for sampling working voltages at two ends of Z lamp beads besides M lamp beads in the illumination branch connected with the sampling module, so as to obtain sampling voltages, wherein Z is not more than N-M and is a positive integer.
Preferably, the load module comprises a DC/DC circuit and a load, and the load comprises a plurality of lamp beads;
the first input end of the DC/DC circuit is the first end of the load module, the second input end of the DC/DC circuit is the second end of the load module, the first output end of the DC/DC circuit is connected with one end of the load, and the second output end of the DC/DC circuit is connected with the other end of the load;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the DC/DC circuit based on the sampling parameter and a target parameter, so that the working parameter of the lighting branch circuit is stabilized at the target parameter.
Preferably, when the DC/DC circuit is a Boost circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Boost circuit based on the sampling parameter and a target parameter so as to stabilize the working parameter of the illumination branch circuit at the target parameter;
the voltage value of N lamp beads in the lighting branch circuit applied by the driving circuit is in positive correlation with the duty ratio of the switch tube.
Preferably, when the DC/DC circuit is a Boost circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Boost circuit based on the sampling parameter and a target parameter so as to stabilize the working parameter of the illumination branch circuit at the target parameter;
when the driving circuit is applied to the N lighting branches with the maximum lamp bead voltage value, the control module is specifically used for controlling the duty ratio of the switching tube to be equal to 1;
when the driving circuit is applied to the N lighting branches with the minimum lamp bead voltage value, the control module is specifically used for controlling the duty ratio of the switching tube to be equal to 0.
Preferably, when the DC/DC circuit is a Buck circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Buck circuit based on the sampling parameter and a target parameter so as to enable the working parameter of the illumination branch to be stabilized at the target parameter;
when the DC/DC circuit is a Flyback circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Flyback circuit based on the sampling parameter and the target parameter, so that the working parameter of the illumination branch is stabilized at the target parameter.
Preferably, the control module comprises an operational amplifier, a resistor, a second capacitor and a driving unit;
the input positive end of the operational amplifier inputs the target parameter, the input negative end of the operational amplifier is respectively connected with the output end of the sampling module and the first end of the second capacitor, the other end of the second capacitor is connected with the first end of the resistor, the second end of the resistor is connected with the output end of the operational amplifier, the output end of the operational amplifier is connected with the input end of the driving unit, and the output end of the driving unit is the output end of the control module;
the operational amplifier is used for performing proportional-integral calculation based on the difference value of the target parameter and the sampling parameter and outputting a voltage signal;
the driving unit is used for converting the voltage signal into a control signal.
Preferably, the method further comprises the following steps:
and the current limiting module is arranged in each lighting branch and is used for clamping the working current of the lighting branch below a preset current.
Preferably, a plurality of lamp beads included in the load and N lamp beads in the lighting branch are integrated in the same lamp.
The application provides a drive circuit, including sampling module, control module and load module, wherein, load module is parallelly connected with M lamp pearl in the illumination branch road, has parallelly connected a load for M lamp pearl in other words. In the dimming process, the control module generates a control signal according to the collected working parameters and target parameters of the lighting branch collected by the sampling module except for the M lamp beads to adjust the equivalent impedance of the load module, namely, the equivalent impedance connected with the M lamp beads in parallel, so that the equivalent impedance of the M lamp beads connected with the load module in parallel is changed, and the working parameters of other lamp beads in the lighting branch except for the M lamp beads are stabilized at the target parameters. In this application, need not control the power of the higher voltage of constant voltage source output, and then reduce the loss on the circuit, and can stabilize the working parameter of lamp pearl at the target parameter, realize the closed loop regulation to the lamp pearl, in addition, load module in this application includes a plurality of lamp pearls, is used for the energy for independent lamp pearl power supply to make and realize illumination or other functions, improved the utilization ratio of energy.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a block diagram of a lighting system in the prior art;
FIG. 2 is a block diagram of a driving circuit according to the present invention;
fig. 3 is a block diagram of a first lighting system provided by the present invention;
fig. 4 is a block diagram of a second lighting system provided by the present invention;
FIG. 5 is a block diagram of a third illumination system provided by the present invention;
FIG. 6 is a diagram illustrating an embodiment of a control module according to the present invention;
FIG. 7 is a block diagram of a fourth lighting system according to the present invention;
fig. 8 is a block diagram of a fifth lighting system according to the present invention;
fig. 9 is a block diagram of a sixth lighting system according to the present invention.
Detailed Description
The core of the invention is to provide a driving circuit, which does not need to control a constant voltage source to output a power supply with higher voltage, so as to reduce the loss on a circuit, and can stabilize the working parameters of the lamp beads at target parameters, thereby realizing closed-loop regulation of the lamp beads.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 2, fig. 2 is a block diagram of a driving circuit according to the present invention, where the driving circuit is applied to a lighting system, the lighting system includes a constant voltage source and multiple lighting branches, an output positive terminal of the constant voltage source is connected to a positive terminal of each lighting branch, an output negative terminal of the constant voltage source is connected to a negative terminal of each lighting branch, each lighting branch includes N beads, at least one lighting branch is provided with a driving circuit, the driving circuit includes a sampling module 11, a control module 12, and a load module 13, and the load module 13 includes multiple beads;
the first end of the load module 13 is connected with one end of M lamp beads in the N lamp beads, the second end of the load module 13 is connected with the other end of the M lamp beads, the output end of the sampling module 11 is connected with the input end of the control module 12, the output end of the control module 12 is connected with the control end of the load module 13, N & gtM & gt 1, and N and M are integers;
the sampling module 11 is used for sampling the working parameters of the lamp beads except for the M lamp beads in the lighting branch connected with the sampling module to obtain sampling parameters;
the control module 12 is used for adjusting the equivalent impedance of the load module 13 based on the sampling parameters and the target parameters so as to stabilize the working parameters at the target parameters;
the load module 13 is configured to change its equivalent impedance according to a signal of its control terminal to obtain electric energy, and supply the electric energy to a plurality of lamp beads included in itself to make the lamp beads emit light.
It should be noted that N, M, etc. mentioned in this application are only an illustration of a number and are not limited, and when there are a plurality of lighting branches, it is not limited that each lighting branch contains the same number of beads. That is, N (or M) in different illumination branches may not be equal.
When the lighting system in the prior art works, because of loss on the power supply line, the voltage of the lighting branch is more likely to be greater than the voltage output to the lighting branch by the constant voltage source, so that the working brightness of the lamp bead on the lighting branch cannot reach the preset brightness, and the working requirement cannot be met.
In order to solve the above problems, the design idea of the present application is: a driving circuit is designed, the output voltage of a constant voltage source does not need to be increased, and the lamp beads in the lighting branch can work at preset voltage so as to work at preset brightness.
Based on this, the application provides a driving circuit, including sampling module 11, control module 12 and load module 13, through connecting a load module 13 in parallel for some lamp pearls (M) in the illumination branch road, then adjust the equivalent impedance of load module 13 based on parameter and working parameter (the equivalent impedance of load module means, in the load module that contains the switch, look into from the input both ends, the ratio between the average value of input voltage and the average value of input current), thereby make the working parameter of other lamp pearls in the illumination branch road except M lamp pearls stabilize at the target parameter, realize the closed-loop regulation to working parameter.
It should be noted that, in the present application, the connection relationship of the N lamp beads is not particularly limited, and all of the N lamp beads may be connected in series, or may be combined in series and parallel, and the following embodiments and the drawings in the specification all use the lamp beads as all of the N lamp beads to be described in series for easy understanding.
As a preferred embodiment, when the operating parameter is the operating current;
the sampling module 11 is specifically configured to sample the operating currents of the lamp beads, other than the M lamp beads, in the lighting branch connected to the sampling module, so as to obtain a sampling current.
Specifically, when the working parameter is working current, the sampling module 11 is a current sampling module 11, and is configured to collect the working currents of the lamp beads other than M in the lighting branch, and feed back the working currents to the control module 12, and if the working currents are not preset currents, the control module 12 adjusts the equivalent impedance of the load module 13, so that the working currents are stabilized at the target current.
Specifically, referring to fig. 3, fig. 3 is a block diagram of a first illumination system provided in the present invention. When all the lamp beads in the lighting branch are connected in series, the working current collected by the sampling module 11 at this time can be the total current of the lighting branch connected with the sampling module, and the total current is the working current of the lamp beads except for the M lamp beads.
Therefore, when the working parameters are working currents, the working states of the lamp beads except the M lamp beads can be sampled, so that the closed-loop control of the lamp beads except the M lamp beads is realized, and the lamp beads except the M lamp beads work at target parameters, namely in a target state.
As a preferred embodiment, when the operating parameter is the operating voltage;
the sampling module 11 is specifically configured to sample working voltages at two ends of Z lamp beads, except for M lamp beads, in the lighting branch connected to the sampling module, so as to obtain a sampling voltage, where Z is equal to or less than N-M, and Z is a positive integer.
Specifically, when the operating parameter is operating voltage, the sampling module 11 is a voltage sampling module 11, and is configured to collect the operating voltages of the M lamp beads in the lighting branch connected to the sampling module 11, and feed back the operating voltages to the control module 12, and if the operating voltages are not preset voltages, the control module 12 adjusts the equivalent impedance of the load module 13 so as to stabilize the operating voltages at the target voltage.
Specifically, referring to fig. 4, fig. 4 is a block diagram of a second illumination system provided in the present invention. When all the lamp beads in the lighting branch are connected in series, the voltage sampling module 11 is connected in a schematic diagram.
Therefore, when the working parameters are working voltages, the working states of the lamp beads except the M lamp beads can be sampled, so that the closed-loop control of the lamp beads except the M lamp beads is realized, and the lamp beads except the M lamp beads work at target parameters, namely, in a target state.
As a preferred embodiment, the load 132 includes a plurality of beads integrated in the same luminaire as the N beads in the lighting branch.
By adjusting the resistance value of the load module 13, it is considered that the load module is a resistor or other linear device, although the adjustment of the operating parameter can be achieved to stabilize the operating parameter at the target parameter. However, energy is converted into heat and consumed, and energy is wasted.
Therefore, the load module 13 in the application uses a plurality of lamp beads, and by adjusting the equivalent impedance of the plurality of lamp beads connected in parallel with the M lamp beads, the adjustment of the working parameters can be realized, so that the working parameters are stabilized at the target parameters, the obtained electric energy can be supplied to the plurality of lamp beads to enable the lamp beads to emit light, and the energy can be recycled. The method for adjusting the equivalent impedance of the plurality of lamp beads in the load module 13 may be to adjust the equivalent impedance of the load module 13 by adjusting a connection relationship between the plurality of lamp beads, or adjusting the number of the plurality of lamp beads, or may be other adjusting methods using a switch circuit (e.g., a DC/DC converter circuit), which is not limited herein.
Through the mode in this application, can carry out reuse with the energy for independent lamp pearl power supply to lamp pearl during operation in load module 13 makes energy effectively utilized in illumination or light filling once more, avoids causing the energy extravagant.
It should be further noted that the lamp beads included in the load module 13 in the present application and the lamp beads in the lighting branch can be integrated in the same lamp, so as to realize the functions of lighting or light supplement.
As a preferred embodiment, the method further comprises the following steps:
and the current limiting module is arranged in each lighting branch and is used for clamping the working current of the lighting branch below the preset current.
Referring to fig. 5, fig. 5 is a block diagram of a third illumination system provided in the present invention. The embodiment aims to provide an implementation mode for improving the safe operation of the lighting system, and particularly, in order to ensure that the lamp beads on each lighting branch in the lighting branches can normally operate, the voltage output by the constant voltage source is generally greater than the maximum voltage of all the lighting branches, so that the working current of the branch with smaller line loss is possibly greater than the preset current for the branch closer to the constant voltage source, thereby possibly generating overcurrent and possibly damaging the lamp beads.
In order to solve the above problem, in the present application, a current limiting module is further disposed in each lighting branch, and it is defined that the working current in the lighting branch does not exceed a preset current, where the preset current may be a rated current of the lamp bead, or may be a certain value smaller than the rated current, and the present application is not limited herein.
It is thus clear that each lamp pearl overflows in can avoiding the illumination branch road through the current limiting module in this application, has further guaranteed the security of each lamp pearl.
To sum up, through the equivalent impedance of adjustment and the parallelly connected load module 13 of M lamp pearls in this application, come to carry out closed loop to the operating parameter of the lamp pearl except that M lamp pearl and adjust, so that it stabilizes at the target parameter, need not control the power of the higher voltage of constant voltage source output, and then reduce the loss on the circuit, and can stabilize the operating parameter of lamp pearl at the target parameter, realize the closed loop to the lamp pearl and adjust, furthermore, load module in this application includes a plurality of lamp pearls, be used for the energy for independent lamp pearl power supply, so that realize illumination or other functions, the utilization ratio of energy has been improved.
On the basis of the above-described embodiment:
as a preferred embodiment, the load module 13 includes a DC/DC circuit 131 and a load 132, and the load 132 includes a plurality of lamp beads;
a first input end of the DC/DC circuit 131 is a first end of the load module 13, a second input end of the DC/DC circuit 131 is a second end of the load module 13, a first output end of the DC/DC circuit 131 is connected with one end of the load 132, and a second output end of the DC/DC circuit 131 is connected with the other end of the load 132;
the control module 12 is specifically configured to adjust the duty cycle or frequency of the switching tube in the DC/DC circuit 131 based on the sampling parameter and the target parameter, so as to stabilize the operating parameter of the lighting branch at the target parameter
The load module 13 in this application may include a DC/DC circuit 131 and a load 132, as shown in fig. 3 and fig. 4, and specifically, the control module 12 adjusts the magnitude of the equivalent impedance of the load module 13 connected to the lighting branch by controlling the duty ratio of the switching tube in the DC/DC circuit 131.
As a preferred embodiment, the control module 12 includes an operational amplifier, a resistor, a second capacitor and a driving unit;
the input positive end of the operational amplifier inputs the target parameter, the input negative end of the operational amplifier is respectively connected with the output end of the sampling module 11 and the first end of the second capacitor, the other end of the second capacitor is connected with the first end of the resistor, the second end of the resistor is connected with the output end of the operational amplifier, the output end of the operational amplifier is connected with the input end of the driving unit, and the output end of the driving unit is the output end of the control module;
the operational amplifier is used for carrying out proportional integral calculation based on the difference value of the target parameter and the sampling parameter and outputting a voltage signal;
the driving unit is used for converting the voltage signal into a control signal.
Referring to fig. 6, fig. 6 is a schematic diagram illustrating a specific implementation manner of a control module 12 according to the present invention, wherein a negative input terminal of an operational amplifier inputs a sampling parameter (working current Ic or working voltage Vc), and a non-inverting input terminal of the operational amplifier is connected to a reference signal for setting a preset value of current or voltage, that is, a target parameter Vr. The output end of the operational amplifier is connected with a driving unit, and the control signal is output according to the output result of the operational amplifier. Specifically, the output of the operational amplifier may be, but is not limited to, a voltage signal, and the driving unit outputs a PWM (Pulse Width Modulation) signal based on the magnitude of the voltage signal output by the operational amplifier, wherein the duty ratio or frequency of the PWM signal varies with the output voltage of the operational amplifier. The PWM signal is output to the control terminal of the switching tube in the DC/DC circuit 131, and the equivalent impedance of the connected load module 13 is controlled by controlling the on and off of the switching tube.
Specifically, for example, in a manner that the lamp beads in the lighting branch are connected in series, the sampling module 11 samples the total current of the lighting branch connected to the input end of the DC/DC circuit 131 to obtain a sampling current of the total current of the lighting branch, and inputs the sampling current and the target current to the input negative terminal and the input positive terminal of the operational amplifier, so that the output voltage amplitude of the operational amplifier is proportional-integral with the difference, where the difference is the difference between the sampling current and the target current; the output voltage of the operational amplifier controls the switching tube in the DC/DC circuit 131 through the driving unit to adjust the duty ratio or frequency of the switching tube, which is equivalent to make the equivalent impedance of the load module 13 connected to the lighting branch change, and the change of the switching tube of the DC/DC circuit 131 corresponds to the change of the input power, that is, the input power of the DC/DC circuit 131 changes along with the amplitude change of the output voltage of the operational amplifier, and further, the total current of the lighting branch of the present path is adjusted to be equal to the target current through the adjustment of the input power of the DC/DC circuit 131.
The sampling module 11 samples voltages at two ends of any other lamp bead except for the M lamp beads in the lighting branch to obtain a sampling voltage, and inputs the sampling voltage and a target voltage into the operational amplifier to enable an output voltage amplitude of the operational amplifier to be in a proportional-integral relationship with a difference value, wherein the difference value is a difference value between the sampling voltage and the target voltage; the output voltage of the operational amplifier controls the switching tube in the DC/DC circuit 131 to adjust the duty ratio or frequency of the switching tube, which is equivalent to changing the equivalent impedance of the load module 13 connected to the lighting branch, so that the input power of the DC/DC circuit 131 changes with the amplitude change of the output voltage of the operational amplifier, and the voltages at the two ends of the Z lamp beads are adjusted to be equal to the target voltage by adjusting the input power of the DC/DC circuit 131.
For example, when the output voltage of the constant voltage source is less than the voltage of the lighting branch, at this time, the total current of the lighting branch will be lower than the target current, the sampling current will be lower than the target current, and the sampling voltage will be lower than the target voltage, at this time, the output voltage of the operational amplifier will be increased, and the duty cycle or frequency of the switching tube in the DC/DC circuit 131 is controlled, so that the input power of the DC/DC circuit 131 changes in the direction of increasing, the total current of the lighting branch will be increased, and this adjustment process is circulated until the working current collected by the sampling module 11 is equal to the target current, and the sampling voltage is equal to the target voltage.
It can be seen that the function of regulating the current on the illumination branch to stabilize it at the target current can be achieved by the DC/DC circuit 131 and the load 132. That is, through the implementation manner of the control module 12, the closed-loop adjustment of the operating states of the lamp beads other than the M lamp beads can be realized, so that the lamp beads are stabilized at the target parameters.
As a preferred embodiment, the voltage values of N lamp beads in the lighting branch applied by the driving circuit are in positive correlation with the duty ratio of the switching tube.
Specifically, the lighting system may include a plurality of lighting branches, and because there is a difference between each of the lamp beads (for example, when two lamp beads having the same specification are both operated at a rated current, voltages at two ends of the two lamp beads may be respectively 3V and 3.3V), even if the current passed by each lamp bead is the same, the voltages of the lamp beads may be different, and therefore, even if each lighting branch includes N lamp beads having the same specification, the voltage values of the lighting branches are not the same. Specifically, the set duty cycle should be larger for the lighting branch with larger voltage value, and correspondingly, the set duty cycle is smaller for the lighting branch with smaller voltage value. Thus setting different duty cycles for different lighting branches.
As a preferred embodiment, when the DC/DC circuit 131 is a Boost circuit;
the control module 12 is specifically configured to adjust a duty ratio or a frequency of a switching tube in the Boost circuit based on the sampling parameter and the target parameter, so that a working parameter of the lighting branch is stabilized at the target parameter;
for the lighting branch circuit with the maximum voltage value of N lamp beads, the duty ratio can be set to 1 or close to 1, and for the lighting branch circuit with the minimum voltage value, the duty ratio can be set to 0 or close to 0.
As a preferred embodiment, when the DC/DC circuit 131 is a Boost circuit;
the control module 12 is specifically configured to adjust a duty ratio or a frequency of a switching tube in the Boost circuit based on the sampling parameter and the target parameter, so that a working parameter of the lighting branch is stabilized at the target parameter;
when the driving circuit is applied to the N lighting branches with the largest lamp bead voltage values, the control module 12 is specifically configured to control the duty ratio of the switching tube to be equal to or close to 1;
when the driving circuit is applied to the lighting branch with the minimum voltage value of the N lamp beads, the control module 12 is specifically used for controlling the duty ratio of the switching tube to be equal to or close to 0.
It should be noted that the above "N lamp bead voltage values" refer to voltage values of N lamp beads that are presented when the same current value flows through N lamp beads in different lighting branches when the DC/DC does not operate. Due to the reasons of the production process of the lamp beads and the like, even if the lamp beads with the same specification flow through the same current, the voltages at two ends of the lamp beads are different, and after the N lamp beads are connected in series, the voltages of the series branches of different series branches appearing when the same current flows are also different, so that when a plurality of lighting branches exist, the voltage values of the N lamp beads in the different lighting branches are different.
The present embodiment aims to provide a specific implementation manner of the DC/DC circuit 131, which can be implemented by a Boost circuit, specifically referring to fig. 7, fig. 7 is a structural block diagram of a fourth lighting system provided by the present invention, and the sampling module 11 is used to collect a total current in the lighting branch. When the DC/DC circuit 131 is a Boost circuit, since the Boost circuit is a Boost circuit, the input end and the output end of the Boost circuit are connected with the lamp beads of the same specification, and the number of the lamp beads connected to the output end needs to be greater than the number of the lamp beads connected to the input end. When the voltage that the constant voltage source provided is less than the comparison in the illumination branch road more, for the normal drive of the lamp pearl in the assurance illumination branch road, first switch can keep on-state (also duty cycle D equals 1) or the state that the duty cycle is close to 1, and at this moment, the equivalent impedance of parallelly connected load module 13 is minimum, and that part of lamp pearl (M lamp pearl) that is parallelly connected with DC/DC circuit 131 input in the illumination branch road is short-circuited, has guaranteed the normal luminousness (N-M lamp pearl) of other lamp pearls.
In addition, because there is the difference between every lamp pearl, supply voltage probably also different, in the illumination branch road that the voltage is higher, sampling current can be less than target current, and control duty cycle D at this moment rises until sampling current equals target current. In the branch with the lowest voltage, the first open tube may be kept in an off state (i.e., the duty ratio D is 0) or a state where the duty ratio is close to 0, and the equivalent impedance of the parallel load module 13 is the largest. Due to the characteristics of the Boost circuit, the designed output voltage is higher than the input voltage, so that the voltage of the lamp beads connected to the output end is higher than the voltage of the M lamp beads connected to the input end; therefore, when duty ratio D control is 0, the lamp pearl of connecting at the output is not driven, has guaranteed the normal drive of connecting at the M lamp pearl of input.
In a preferred embodiment, the DC/DC circuit 131 is a Buck circuit;
the control module 12 is specifically configured to adjust a duty cycle or a frequency of a switching tube in the Buck circuit based on the sampling parameter and a target parameter, so that an operating parameter of the lighting branch is stabilized at the target parameter.
When a Buck circuit (Buck circuit) is selected, please refer to fig. 8 in detail, and fig. 8 is a block diagram of a fifth lighting system according to the present invention. Because the characteristic of Buck circuit, the output voltage of design must be less than input voltage, consequently connects the voltage that is less than the voltage of connecting the M lamp pearls of input at the lamp pearl of output. When the specifications of the lamp beads are the same, the number of the lamp beads connected to the output end is less than M.
In addition, a Boost circuit, such as a Boost-Buck circuit, may also be used in the present application, and is not described herein again.
It should be noted that, in the selection of the topology of the DC/DC circuit 131, a Boost circuit or a buck-Boost circuit, such as a Boost circuit, is preferentially selected, which has the beneficial effect that, for the lighting branch with higher voltage, the input power of the DC/DC circuit 131 controlled by the control switch tube is larger, resulting in that the input voltage of the DC/DC circuit 131 is also relatively lower.
Thus, the highest voltage lighting branch, whose DC/DC circuit 131 has the lowest input voltage; conversely, the lighting branch with the lowest voltage has the highest input voltage of the DC/DC circuit 131.
The problem of the lighting branch with higher voltage is the most advanced or urgent need to be solved in the driving system, if the Boost circuit is selected to realize the DC/DC circuit 131, the minimum input power of the DC/DC circuit 131 is set according to the path with the lowest voltage in the lighting branch, so that in the branches with higher voltage of the lighting branch, the input power of the DC/DC circuit 131 is higher than the minimum input power, and the problem that the output voltage of the constant voltage source is smaller than the voltage of the lighting branch can be solved under all conditions.
If the step-down circuit is selected, in order to ensure that the DC/DC circuit 131 can work under any condition, the minimum input power of the DC/DC circuit 131 needs to be set according to the path with the highest voltage of the lighting branch (the input power of the DC/DC circuit 131 corresponding to the path with the highest voltage of the lighting branch needs to be the largest, that is, the input voltage of the DC/DC circuit 131 is the lowest), which results in that the designed DC/DC circuit 131 restricts that the voltage of the lighting branch cannot be too high, and restricts the use occasions of the DC/DC power processing circuit.
As a preferred embodiment, the DC/DC circuit 131 is a Flyback circuit including a first switch, an isolation transformer, a first diode, and a first capacitor;
the first end of the primary winding of the isolation transformer is a first input end of the DC/DC circuit 131, the second end of the primary winding is connected with the first end of the first switch, the second end of the first switch is a second input end of the DC/DC circuit 131, the first end of the secondary winding of the isolation transformer is connected with the anode of the first diode, the cathode of the first diode is connected with the first end of the first capacitor and serves as the first output end of the DC/DC circuit 131, the second end of the secondary winding is connected with the second end of the first capacitor and serves as the second output end of the DC/DC circuit 131, the control end of the first switch is connected with the output end of the control module 12, and the first end of the primary winding and the second end of the secondary winding are the same-name ends;
the control module 12 is specifically configured to adjust a duty ratio of the first switch based on the sampling parameter and the target parameter, so that the operating parameter of the lighting branch is stabilized at the target parameter.
In this embodiment, in addition to the non-isolated circuits such as the Boost circuit, the Buck circuit, and the Boost-Buck circuit described above, an isolated circuit may be used to implement the DC/DC circuit 131, for example, a Flyback circuit, specifically referring to fig. 9, fig. 9 is a structural block diagram of a sixth lighting system provided by the present invention.
It is to be noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A driving circuit is characterized by being applied to a lighting system, wherein the lighting system comprises a constant voltage source and a plurality of lighting branches, the positive output end of the constant voltage source is connected with the positive end of each lighting branch, the negative output end of the constant voltage source is connected with the negative end of each lighting branch, each lighting branch comprises N lamp beads, a driving circuit is arranged on at least one lighting branch, the driving circuit comprises a sampling module, a control module and a load module, and the load module comprises a plurality of lamp beads;
the first end of the load module is connected with one end of M lamp beads in the N lamp beads, the second end of the load module is connected with the other end of the M lamp beads, the output end of the sampling module is connected with the input end of the control module, the output end of the control module is connected with the control end of the load module, N & gtM & gt is larger than or equal to 1, and N and M are integers;
the sampling module is used for sampling the working parameters of the lamp beads except for the M lamp beads in the illumination branch circuit connected with the sampling module to obtain sampling parameters;
the control module is used for adjusting the equivalent impedance of the load module based on the sampling parameter and a target parameter so as to enable the working parameter to be stabilized at the target parameter;
the load module is used for changing the equivalent impedance of the load module according to the signal of the control end of the load module to obtain electric energy, and the electric energy is supplied to the plurality of lamp beads included in the load module to enable the lamp beads to emit light.
2. The drive circuit of claim 1, wherein the operating parameter is an operating current;
the sampling module is specifically used for sampling the working currents of the lamp beads, except M lamp beads, in the illumination branch circuit connected with the sampling module, so as to obtain the sampling currents.
3. The drive circuit of claim 1, wherein when the operating parameter is an operating voltage;
the sampling module is specifically used for sampling working voltages at two ends of Z lamp beads besides M lamp beads in the illumination branch connected with the sampling module, so as to obtain sampling voltages, wherein Z is not more than N-M and is a positive integer.
4. The driving circuit of claim 1, wherein the load module comprises a DC/DC circuit and a load, the load comprising a plurality of lamp beads;
the first input end of the DC/DC circuit is the first end of the load module, the second input end of the DC/DC circuit is the second end of the load module, the first output end of the DC/DC circuit is connected with one end of the load, and the second output end of the DC/DC circuit is connected with the other end of the load;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the DC/DC circuit based on the sampling parameter and a target parameter, so that the working parameter of the lighting branch circuit is stabilized at the target parameter.
5. The drive circuit according to claim 4, wherein when the DC/DC circuit is a Boost circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Boost circuit based on the sampling parameter and a target parameter so as to stabilize the working parameter of the illumination branch circuit at the target parameter;
the voltage value of N lamp beads in the lighting branch circuit applied by the driving circuit is in positive correlation with the duty ratio of the switch tube.
6. The drive circuit according to claim 4, wherein when the DC/DC circuit is a Boost circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Boost circuit based on the sampling parameter and a target parameter so as to stabilize the working parameter of the illumination branch circuit at the target parameter;
when the driving circuit is applied to the N lighting branches with the maximum lamp bead voltage value, the control module is specifically used for controlling the duty ratio of the switching tube to be equal to 1;
when the driving circuit is applied to the N lighting branches with the minimum lamp bead voltage value, the control module is specifically used for controlling the duty ratio of the switching tube to be equal to 0.
7. The drive circuit of claim 4, wherein when the DC/DC circuit is a Buck circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Buck circuit based on the sampling parameter and a target parameter so as to enable the working parameter of the illumination branch to be stabilized at the target parameter;
or, when the DC/DC circuit is a Flyback circuit;
the control module is specifically used for adjusting the duty ratio or the frequency of a switching tube in the Flyback circuit based on the sampling parameter and the target parameter, so that the working parameter of the illumination branch is stabilized at the target parameter.
8. The driving circuit of claim 1, wherein the control module comprises an operational amplifier, a resistor, a second capacitor, and a driving unit;
the input positive end of the operational amplifier inputs the target parameter, the input negative end of the operational amplifier is respectively connected with the output end of the sampling module and the first end of the second capacitor, the other end of the second capacitor is connected with the first end of the resistor, the second end of the resistor is connected with the output end of the operational amplifier, the output end of the operational amplifier is connected with the input end of the driving unit, and the output end of the driving unit is the output end of the control module;
the operational amplifier is used for performing proportional-integral calculation based on the difference value of the target parameter and the sampling parameter and outputting a voltage signal;
the driving unit is used for converting the voltage signal into a control signal.
9. The drive circuit of claim 1, further comprising:
and the current limiting module is arranged in each lighting branch and is used for clamping the working current of the lighting branch below a preset current.
10. The driver circuit according to any of claims 4-9, wherein the load comprises a plurality of beads integrated in the same luminaire as the N beads in the lighting branch.
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| CN202111517604.XA CN114205970A (en) | 2021-12-13 | 2021-12-13 | Driving circuit |
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| CN202111517604.XA CN114205970A (en) | 2021-12-13 | 2021-12-13 | Driving circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117039610A (en) * | 2023-10-10 | 2023-11-10 | 深圳市柠檬光子科技有限公司 | Laser driving circuit and driving method, lighting system and laser radar |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101730968A (en) * | 2007-06-15 | 2010-06-09 | 费希尔控制产品国际有限公司 | The input regulated DC to DC converter that is used for power scavenging |
| CN102595680A (en) * | 2011-01-07 | 2012-07-18 | 英飞特电子（杭州）有限公司 | Multi-output LED (Light-Emitting Diode) constant-current driving circuit |
| CN102833903A (en) * | 2011-06-14 | 2012-12-19 | 英飞特电子（杭州）股份有限公司 | Load drive circuit |
| US20150312981A1 (en) * | 2013-01-22 | 2015-10-29 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | Current adjusting device and adjustment method thereof |
| CN106787088A (en) * | 2017-01-18 | 2017-05-31 | 西北工业大学 | It is applied to the self powered supply management circuit of discontinuous piezoelectric energy acquisition system |
| CN109462339A (en) * | 2018-10-16 | 2019-03-12 | 台州宏远电力设计院有限公司 | Impedance matching methods based on circuit duty ratio |
| CN113473676A (en) * | 2021-06-07 | 2021-10-01 | 四维生态科技（杭州）有限公司 | Control method and device of LED driving circuit for plant illumination and terminal |
-
2021
- 2021-12-13 CN CN202111517604.XA patent/CN114205970A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101730968A (en) * | 2007-06-15 | 2010-06-09 | 费希尔控制产品国际有限公司 | The input regulated DC to DC converter that is used for power scavenging |
| CN102595680A (en) * | 2011-01-07 | 2012-07-18 | 英飞特电子（杭州）有限公司 | Multi-output LED (Light-Emitting Diode) constant-current driving circuit |
| CN102833903A (en) * | 2011-06-14 | 2012-12-19 | 英飞特电子（杭州）股份有限公司 | Load drive circuit |
| US20150312981A1 (en) * | 2013-01-22 | 2015-10-29 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | Current adjusting device and adjustment method thereof |
| CN106787088A (en) * | 2017-01-18 | 2017-05-31 | 西北工业大学 | It is applied to the self powered supply management circuit of discontinuous piezoelectric energy acquisition system |
| CN109462339A (en) * | 2018-10-16 | 2019-03-12 | 台州宏远电力设计院有限公司 | Impedance matching methods based on circuit duty ratio |
| CN113473676A (en) * | 2021-06-07 | 2021-10-01 | 四维生态科技（杭州）有限公司 | Control method and device of LED driving circuit for plant illumination and terminal |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117039610A (en) * | 2023-10-10 | 2023-11-10 | 深圳市柠檬光子科技有限公司 | Laser driving circuit and driving method, lighting system and laser radar |
| CN117039610B (en) * | 2023-10-10 | 2024-01-16 | 深圳市柠檬光子科技有限公司 | Laser driving circuit and driving method, lighting system and laser radar |
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