Explosion-proof lighting lamp and brightness control method thereof

Abstract

The present application relates to the field of explosion-proof lighting technology, and specifically to an explosion-proof lighting lamp and a brightness control method thereof, the method comprising: collecting the temperature of the explosion-proof lighting lamp and the current and voltage of the brightness control circuit; extracting the frequency domain change characteristics of each harmonic frequency of the current to obtain the power influence weight; obtaining the harmonic current; obtaining the temperature influence weight according to the change trend of the lighting lamp temperature and the correlation between the change and the harmonic current; finally, calculating the total reactive power by combining the reactive power of the harmonic and reactive current; determining the reactive compensation amount according to the reactive power, and further determining the capacitor capacity to achieve reactive compensation. The present application aims to reduce the adverse effects of harmonics and reactive currents in the brightness control circuit, thereby enhancing the brightness control stability of the explosion-proof lighting lamp.

Description

Technical Field

[0001] The present application relates to the technical field of explosion-proof lighting, and in particular to an explosion-proof lighting lamp and a brightness control method thereof. Background Art

[0002] Explosion-proof lighting lamps are mainly used in flammable and explosive dangerous places, such as petrochemical, natural gas, coal mines, etc. In these environments, the performance of lighting equipment is crucial to ensure personal safety and property safety, and a very important part of the performance of lighting equipment is the brightness control of the lamp. The existing technology achieves brightness control by adjusting the duty cycle and changing the average current flowing through the lamp.

[0003] However, reactive current will be generated in the circuit, which will reduce the power factor of the lighting lamp, thus affecting its service life and the stability of brightness control. At the same time, harmonics in the circuit will also cause current and voltage fluctuations in the lighting lamp, thereby increasing the operating temperature of the lamp and reducing the stability of brightness control. Although the existing technology has adjusted the average current, it still does not fully consider the influence of reactive current and harmonics, so there is still a certain error in brightness control. Summary of the invention

[0004] In view of the above, it is necessary to provide an explosion-proof lighting lamp and a brightness control method thereof to solve the above problems.

[0005] The first aspect of the present application provides a method for controlling the brightness of an explosion-proof lighting lamp, the method comprising:

[0006] Collect the temperature of the explosion-proof lighting lamp within a preset time period and the current and voltage of the brightness control circuit in the explosion-proof lighting lamp;

[0007] The current of a preset time length is used as the segmented current; each harmonic frequency is preset, and the fluctuation degree of each harmonic frequency is determined based on the discrete degree of the amplitude information and phase information of each harmonic frequency of the segmented current; the difference between the fluctuation degree of each harmonic frequency and all harmonic frequencies is analyzed to determine the power impact weight of each harmonic frequency;

[0008] The amplitude information and phase information of each harmonic frequency of the segmented current are integrated, and the harmonic current of each harmonic frequency is obtained by using inverse Fourier transform; the temperature influence weight is determined according to the peak distribution characteristics and temperature distribution characteristics of the harmonic current of all segmented currents at each harmonic frequency;

[0009] According to the power influence weights of all harmonic frequencies and the reactive power of the corresponding harmonic currents, combined with the temperature influence weights, the reactive compensation amount is confirmed, and the capacitor is selected according to the voltage of the brightness control circuit to control the reactive power generated by the brightness control circuit in the explosion-proof lighting lamp.

[0010] The fluctuation degree of each harmonic frequency is specifically a fusion result of the discrete degree of amplitude information and the discrete degree of phase information of each harmonic frequency.

[0011] The determination of the power impact weight of each harmonic frequency is specifically as follows:

[0012] For all harmonic frequencies except the first harmonic frequency, the cumulative sum of the fluctuation degrees is calculated; based on the ratio of the fluctuation degree of each harmonic frequency except the first harmonic frequency to the cumulative sum, the power impact weight of each harmonic frequency is obtained.

[0013] The process of determining the temperature influence weight includes:

[0014] According to the peak distribution of the harmonic current of all segment currents at each harmonic frequency, the peak sequence of each harmonic frequency is obtained;

[0015] The temperature of the preset time period is divided based on the number of elements in the peak sequence to obtain an average temperature sequence;

[0016] A time series decomposition algorithm is used for the temperature in a preset time period to obtain a trend sequence, and a first-order difference sequence of the trend sequence is obtained;

[0017] Based on the elements of the first-order difference sequence, a temperature change index is obtained;

[0018] The temperature influence weight of the explosion-proof lighting is recorded as B, and its formula is: ;in, is the maximum value of the Pearson correlation coefficient between the mean temperature series and each peak series; is the temperature change index; is the temperature at the last moment in the preset time period, It is the upper limit of the safe operating temperature of explosion-proof lighting lamps.

[0019] The peak sequence of each harmonic frequency is obtained as follows:

[0020] For the harmonic current of each segment current at each harmonic frequency, the average value of the peak value of each harmonic current is obtained and recorded as the peak value mean; all the peak values ​​at each harmonic frequency are combined into a peak value sequence of each harmonic frequency.

[0021] Wherein, obtaining the average temperature sequence comprises:

[0022] Obtaining the ratio of the number of temperatures in a preset time period to the number of elements in the peak sequence;

[0023] If the ratio is an integer, the ratio is used as the number of segments into which the temperature of the preset time period is divided, and the temperature average of each segment after the division is calculated; the sequence composed of all temperature averages is used as the average temperature sequence;

[0024] If the ratio is not an integer, then The number of temperatures divided into segments is the rounded-down value of the ratio, and all remaining elements constitute the first paragraph; among them, Represents the number of elements in the peak sequence.

[0025] The temperature change index is specifically the proportion of positive numbers in the first-order difference sequence.

[0026] The process of confirming the reactive power compensation amount is as follows:

[0027] The reactive power of the harmonic current corresponding to all subharmonic frequencies is synthesized and combined with the temperature influence weight to obtain the reactive power of the harmonic;

[0028] The reactive power compensation amount is recorded as , its formula form is: ; is the temperature effect weight, is the reactive power of the reactive current, is the reactive power of the harmonics.

[0029] Wherein, the capacity of the selected capacitor is:

[0030] Get the angular frequency in the brightness control circuit, recorded as ; The capacity of the capacitor is recorded as , its formula form is: ;in, is the capacitor capacity, is the reactive power compensation amount, is the voltage of the brightness control circuit.

[0031] In a second aspect, an embodiment of the present application further provides an explosion-proof lighting lamp, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above-mentioned methods when executing the computer program.

[0032] In the above scheme, the temperature of the explosion-proof lighting lamp within a preset time period and the current and voltage of the brightness control circuit in the explosion-proof lighting lamp are collected, which is helpful for subsequent analysis of interference factors when controlling the brightness of the explosion-proof lighting lamp from multiple angles; the amplitude information and phase information of each harmonic frequency are extracted, and the fluctuation degree of each harmonic frequency and the power influence weight are confirmed; its beneficial effect is that it can accurately identify and quantify the impact of each harmonic frequency on system performance, thereby improving the accuracy of subsequent reactive compensation; according to the correlation between the temperature of the lighting lamp and the change of harmonic current, as well as the temperature change trend, the temperature influence coefficient is obtained, which improves the accuracy of measuring the operating status of the lighting lamp and helps to enhance the stability of the brightness control of the lighting lamp; finally, the calculation of the total reactive power improves the accuracy of the reactive power calculation, which helps to reduce the negative impact of harmonics on explosion-proof lighting fixtures, improve the stability and efficiency of the system, and further extend the service life of the equipment. In this way, when controlling the brightness of explosion-proof lighting lamps, not only the influence of harmonics and reactive current in the brightness control circuit is considered, but also the different influences of each harmonic component on the stability of brightness control, as well as the influence of changes in the operating temperature of the explosion-proof lighting lamp on the stability of brightness control are considered. This allows the subsequent reactive compensation to better eliminate the negative influence of harmonics and reactive current in the brightness control circuit, thereby improving the stability of the brightness control of the explosion-proof lighting lamp. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A flowchart of a method for controlling the brightness of an explosion-proof lighting lamp provided in one embodiment of the present application;

[0034] Figure 2 A schematic diagram of the relationship between temperature and harmonic current provided in one embodiment of the present application;

[0035] Figure 3 A schematic diagram of the relationship between temperature and failure rate of electronic components provided in one embodiment of the present application. DETAILED DESCRIPTION

[0036] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" and the like are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "or", "for example" and the like is intended to present related concepts in a concrete manner.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0038] It should also be noted that the terms "first" and "second" in this application and the accompanying drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flow chart includes one or more steps for implementing the method. Without departing from the scope of protection of the present application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0040] The specific scheme of an explosion-proof lighting lamp and a brightness control method thereof provided by the present application is described in detail below with reference to the accompanying drawings.

[0041] See also Figure 1 , which shows a flowchart of a method for controlling the brightness of an explosion-proof lighting lamp provided by an embodiment of the present application, the method comprising the following steps:

[0042] The first step: collecting the temperature of the explosion-proof lighting lamp within a preset time period and the current and voltage of the brightness control circuit in the explosion-proof lighting lamp.

[0043] The brightness control system of explosion-proof lighting lamps is composed of a brightness signal given module, a brightness signal receiving module and a brightness control adjustment module. The brightness signal given module generates a brightness signal and transmits the signal to the brightness signal receiving module. The brightness signal receiving module converts the brightness signal into a PWM pulse and transmits it to the brightness control adjustment module. The brightness control adjustment module is a brightness control circuit, which controls the driving current of the explosion-proof lighting lamp according to the PWM pulse to achieve brightness control and adjustment of the corresponding lighting lamp. In this process, the reactive current and harmonic waves generated by the brightness control adjustment module will affect the accuracy and stability of the brightness control, so reactive compensation is required.

[0044] By installing a voltage sensor and a current sensor at the input end of the brightness control adjustment module, the voltage and current of the brightness control circuit are collected. In this embodiment, the collection frequency is set to 1KHz, and the collection time is 10 minutes; the implementer can adjust it according to the actual situation; the temperature sensor installed on the explosion-proof lighting lamp housing is used to collect the temperature of the lamp. The collection time is 10 minutes and the collection frequency is once per second. The collected current and voltage are respectively formed into corresponding sequences according to the collection order. In this embodiment, all sequences are normalized using the maximum value normalization method to obtain normalized voltage sequences, current sequences, and temperature sequences. The implementer can select a suitable normalization method on his own, and this application does not limit this.

[0045] The second step: taking the current of a preset time length as the segmented current; preset each harmonic frequency, and confirming the fluctuation degree of each harmonic frequency based on the discrete degree of the amplitude information and phase information of each harmonic frequency of the segmented current; analyzing the difference in the fluctuation degree between each harmonic frequency and all harmonic frequencies, and confirming the power influence weight of each harmonic frequency.

[0046] In the brightness control circuit of explosion-proof lighting, the harmonics in the circuit will cause fluctuations in voltage and current, making the stability of brightness control relatively poor, and harmonics will cause temperature fluctuations when the lamp is working. The increase in harmonics will cause the lamp to generate higher temperatures when working. At the same time, these harmonic components will increase the reactive power in the brightness control circuit, reducing the power factor of the lighting, so reactive compensation is required to eliminate the impact of harmonic components on brightness control. Secondly, reactive current will also cause the power factor of the lighting to decrease, so reactive compensation is also required to improve the power factor of the lighting, thereby ensuring the accuracy and stability of the brightness control of the lighting.

[0047] When harmonic components are generated in the circuit, the harmonics will affect the stability of the brightness control, so reactive compensation is required to weaken its influence. However, harmonics are composed of multiple waves (such as second harmonics and third harmonics), and each wave has a different influence. If the weight of each wave is exactly the same when calculating the reactive compensation amount, some harmonics may still have a large residual component after reactive compensation, resulting in poor compensation effect. In order to achieve a good compensation effect for all harmonics, it is necessary to calculate the influence weight of each harmonic and make weighted adjustments when calculating the reactive power of the harmonic current.

[0048] The current sequence is divided according to the acquisition time. Each current data of a preset time length is a segment. In this embodiment, the preset time length is 10 seconds, and the implementer can set it according to the actual situation. Each segment of data constitutes a corresponding segmented current sequence according to the acquisition time. Fourier transform is used for each segmented current sequence to output a complex sequence of each segmented current sequence, where the complex sequence contains the amplitude and phase information of the signal at different frequencies. Then, the integer multiple frequencies of the fundamental frequency are selected in turn as the harmonic frequencies, and the maximum integer multiple selected is times, in this embodiment, the fundamental frequency is 50 Hz, The value is 20. As Fourier transform is a well-known technology, the specific process will not be described in detail.

[0049] The amplitude and phase of each harmonic frequency corresponding to each segmented current sequence are obtained, and the amplitude of the same harmonic frequency is used to form the amplitude sequence of the corresponding harmonic frequency according to the sequence of the segmented current sequence elements, and the phase of the same harmonic frequency is used to form the phase sequence of the corresponding harmonic frequency according to the sequence of the segmented current sequence elements, so that the amplitude sequence and phase sequence of all harmonic frequencies can be obtained.

[0050] The result of the fusion of the discrete degree of the amplitude information and the discrete degree of the phase information of each harmonic frequency is used as the fluctuation degree of each harmonic frequency. In this embodiment, the fluctuation degree of each harmonic frequency is measured by the discrete degree of amplitude and phase, that is, ,in, represents the fluctuation degree of the i-th harmonic frequency, , They are respectively the coefficient of variation of the amplitude sequence and the coefficient of variation of the phase sequence of the i-th harmonic frequency; in some other embodiments, the degree of dispersion can be measured by the standard deviation; in some other embodiments, the coefficient of variation can be replaced by the interquartile range.

[0051] Calculate the power impact weight of each harmonic frequency so that weighted adjustment can be made in the subsequent calculation of the reactive power of the harmonic to ensure the stability of brightness adjustment. The formula is: ;in, is the power impact weight of the jth harmonic frequency, , are the fluctuation degrees of the i-th and j-th harmonic frequencies, respectively. It is the maximum multiple of the harmonic frequency relative to the fundamental frequency.

[0052] It should be noted that since the first harmonic is the fundamental wave, the calculation of the harmonic power impact weight should start from the second harmonic, that is, In addition, in order to avoid the fluctuation degree being 0, which results in the power influence weight of the corresponding harmonic frequency being 0, 1 is added to avoid the weight being 0, so that the influence of each harmonic frequency can be considered in the subsequent weighting.

[0053] It is understandable that when the fluctuation of a certain harmonic frequency is large, its control effect on brightness stability is more significant. Therefore, when performing reactive power compensation, it is necessary to pay more attention to the harmonic frequency in order to achieve a more effective compensation effect.

[0054] The third step: synthesize the amplitude information and phase information of each harmonic frequency of the segmented current, use inverse Fourier transform to obtain the harmonic current of each harmonic frequency; obtain the peak sequence of each harmonic frequency according to the peak distribution of the harmonic current of all segmented currents at each harmonic frequency; divide the temperature of the preset time period based on the number of elements in the peak sequence, and confirm the temperature influence weight of the explosion-proof lighting based on the similarity between the distribution characteristics of each temperature segment after division and the peak sequence, combined with the temperature change trend characteristics within the preset time period.

[0055] Harmonics will cause the operating temperature of the lighting to increase. Therefore, in order to ensure the safe operation of the lighting, the reactive power of the harmonics needs to be adjusted according to its temperature change index. When the temperature of the lighting is affected by harmonics, the greater the harmonic current, the greater the temperature increase; conversely, the temperature will decrease when the harmonics are reduced, which shows that there is a positive correlation between temperature and harmonic current. The relationship between temperature and harmonic current is shown in the figure below. Figure 2 However, in addition to the influence of harmonic current, the flow of normal current will also cause the temperature to rise, so overall, the temperature shows an upward trend. Secondly, the increase in the temperature of explosion-proof lighting lamps may cause temperature drift in internal electronic components, thereby increasing the failure rate and affecting the stability of brightness adjustment. Among them, the relationship between temperature and electronic component failure rate is shown in the figure below. Figure 3 As shown, Figure 3 The dotted line in the figure indicates the maximum rated temperature of 70°C. Figure 3 It can be seen that before the maximum rated temperature, the failure rate increases slowly, and after the maximum rated temperature, the failure rate increases faster with the increase of temperature. Therefore, it is necessary to properly adjust the reactive power of harmonics according to the temperature change of explosion-proof lighting lamps to achieve more effective compensation effect and reduce the negative impact on the temperature of lighting lamps.

[0056] Extract the information of the same harmonic frequency from each segmented current sequence to form a corresponding complex sequence of harmonic frequencies; then, take the complex sequence of each harmonic frequency of each segmented current sequence as input, apply inverse Fourier transform, and output the corresponding time domain signal, representing the harmonic current of each segmented current sequence at the harmonic frequency; it should be understood that the harmonic current can reflect the performance of the segmented current sequence at a specific harmonic frequency. Among them, inverse Fourier transform is a well-known technology, and the specific process is not repeated here.

[0057] For the harmonic current of each segmented current sequence at each harmonic frequency, the mean of all peak values ​​in each harmonic current is calculated, and the peak mean values ​​of all segmented current sequences are arranged in the order of the segmented current sequences to form a peak sequence of the harmonic current corresponding to the harmonic frequency. In this way, the peak sequence of each harmonic frequency is obtained.

[0058] It can be understood that the number of elements of the peak sequence is the same as the number of segmented current sequences, so the number of elements of the peak sequences of different subharmonic frequencies is the same.

[0059] Get the ratio of the number of temperatures in the preset time period to the number of elements in the peak sequence; if the ratio is an integer, use the ratio as the number of segments into which the temperature in the preset time period is divided, and calculate the temperature mean of each segment after division; take the sequence composed of all temperature means as the average temperature sequence; if the ratio is not an integer, The number of temperatures divided into segments is the rounded-down value of the ratio, and all remaining elements constitute the first paragraph; among them, Represents the number of elements in the peak sequence.

[0060] The temperature sequence is used as input, and the seasonal trend decomposition using Loess (STL) algorithm is used to output the trend sequence, and then the first-order difference sequence of the trend sequence is calculated. Among them, the STL decomposition algorithm is a well-known technology, and the specific process is not repeated here.

[0061] Based on the above analysis, the temperature impact weight of the lighting lamp is calculated, and the reactive power of the harmonic is adjusted to ensure the operating safety of the lighting lamp and the stability of the brightness control. The temperature impact weight of the explosion-proof lighting lamp is recorded as B, and its formula is: ;in, is the maximum value of the Pearson correlation coefficient between the average temperature series and each peak series, is the temperature change index, specifically the proportion of positive numbers in the first-order difference sequence; is the last element in the temperature sequence, i.e. is the temperature at the last moment in the preset time period; It is the upper limit of the safe working temperature of explosion-proof lighting. The purpose of the exponential function is to avoid the denominator being 0; the purpose of the denominator plus 1 is to limit the increase speed of the temperature influence weight, to avoid the exponential function falling too fast. Increase rapidly.

[0062] It should be understood that when the temperature of the lighting lamp caused by the harmonic current continues to increase and is close to the safe temperature of the lighting lamp, the change of the harmonic current and the change of the temperature should show a positive correlation, that is, The temperature series shows an increasing trend as a whole, that is, At the same time, when the temperature sequence is closer to the safe temperature of the lighting lamp, in order to ensure the safe operation of the lighting lamp, a greater weight needs to be given to the temperature, that is, the more serious the impact of the temperature, Smaller; therefore, when the harmonic current has a more serious impact on the temperature of the lighting lamp, the temperature influence weight On the contrary, when the harmonic current has a smaller impact on temperature, the temperature influence weight The smaller it is, even 0.

[0063] The fourth step: obtain the reactive power of the harmonic current of each harmonic frequency; confirm the reactive compensation amount according to the power influence weights of all harmonic frequencies and the reactive power of the corresponding harmonic current, combined with the temperature influence weights, select the capacitor according to the voltage of the brightness control circuit, and control the reactive power generated by the brightness control circuit in the explosion-proof lighting lamp.

[0064] When calculating the reactive power caused by harmonic current, it is necessary to first calculate the reactive power caused by each harmonic component separately, and then take the cumulative sum of the reactive powers corresponding to all harmonic components as the total reactive power. However, since different harmonic components have different degrees of influence on the stability of the brightness control of the lighting lamp, it is necessary to introduce power impact weights for weighted accumulation. This method ensures that the harmonic components that have a more significant impact on the brightness control have a higher weight in the reactive compensation process, thereby more effectively improving the stability of the overall brightness control; secondly, since harmonics will cause changes in the temperature of the lighting lamp, affecting the safe use of the lighting lamp and the stability of the brightness control, it is also necessary to introduce temperature impact weights to ensure the safe operation of the lighting lamp.

[0065] Based on the above analysis, the reactive power compensation amount is calculated by combining the power impact weight, temperature impact weight and reactive power of reactive current: ;in, is the reactive power compensation amount, is the temperature effect weight, is the reactive power of the reactive current, is the reactive power of the harmonic. In this embodiment, is the weighted cumulative sum of the harmonic current reactive power corresponding to all harmonic frequencies, that is, , It is The power impact weight of subharmonic frequencies, It is The subharmonic frequency corresponds to the reactive power of the harmonic current, It is the maximum multiple of the harmonic frequency relative to the fundamental frequency. The calculation of reactive power of reactive current is a well-known technique, and the specific process will not be repeated here.

[0066] In the brightness control circuit, capacitors are connected in parallel, and the switching of capacitors is adjusted according to the reactive compensation amount, so that the capacitors can be used for reactive compensation. Specifically, according to the capacitor capacity calculation formula: ;in, is the capacitor capacity, is the reactive power compensation amount, is the angular frequency, calculated from the AC frequency, is the voltage of the brightness control circuit. After the capacitor capacity is calculated, the capacitor capacity connected to the circuit is adjusted using the capacitor automatic switching device, thereby compensating for the reactive power caused by harmonics and reactive current.

[0067] In this way, when using PWM technology to control the brightness of explosion-proof lighting, the problem that harmonics and reactive currents in the circuit will cause the brightness control of the lighting to be unstable is taken into consideration. Harmonics and reactive currents are suppressed through reactive compensation, making the brightness control more stable. However, when calculating the reactive power of harmonics, different harmonic currents have different effects on the stability of brightness control, and the increase in the operating temperature of the lighting caused by harmonics will also affect the stability of the brightness control of the lighting. Therefore, when calculating the reactive power, both the weights of different harmonic frequencies and the weights of the temperature are considered, so that more stable brightness control and safe operation of explosion-proof lighting can be achieved after reactive compensation.

[0068] Based on the same inventive concept as the above method, an embodiment of the present application also provides an explosion-proof lighting lamp, including a memory, a processor, and a computer program stored in the memory and running on the processor, and when the processor executes the computer program, the steps of any one of the above-mentioned methods for controlling the brightness of an explosion-proof lighting lamp are implemented.

[0069] In summary, the embodiment of the present application collects the temperature of the explosion-proof lighting lamp within a preset time period and the current and voltage of the brightness control circuit in the explosion-proof lighting lamp, which is helpful for subsequent analysis of interference factors when controlling the brightness of the explosion-proof lighting lamp from multiple angles; extracts the amplitude information and phase information of each harmonic frequency, and confirms the fluctuation degree of each harmonic frequency and the power influence weight; its beneficial effect is that it can accurately identify and quantify the impact of each harmonic frequency on the system performance, thereby improving the accuracy of subsequent reactive compensation; according to the correlation between the temperature of the lighting lamp and the change of the harmonic current, as well as the temperature change trend, the temperature influence coefficient is obtained, thereby improving the accuracy of measuring the operating status of the lighting lamp, and helping to enhance the stability of the brightness control of the lighting lamp; finally, the calculation of the total reactive power improves the accuracy of the reactive power calculation, which helps to subsequently reduce the negative impact of harmonics on explosion-proof lighting fixtures, improve the stability and efficiency of the system, and further extend the service life of the equipment. In this way, when controlling the brightness of explosion-proof lighting lamps, not only the influence of harmonics and reactive current in the brightness control circuit is considered, but also the different influences of each harmonic component on the stability of brightness control, as well as the influence of changes in the operating temperature of the explosion-proof lighting lamp on the stability of brightness control are considered. This allows the subsequent reactive compensation to better eliminate the negative influence of harmonics and reactive current in the brightness control circuit, thereby improving the stability of the brightness control of the explosion-proof lighting lamp.

[0070] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two continuous boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two continuous operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0071] For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the basic features of the present application. Therefore, no matter from which point of view, the above embodiments of the present application should be regarded as exemplary and non-restrictive; the technical solutions recorded in the above embodiments are modified, or some of the technical features are replaced by equivalents, which does not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for controlling the brightness of an explosion-proof lighting lamp, characterized in that: The method comprises the following steps: Collect the temperature of the explosion-proof lighting lamp within a preset time period and the current and voltage of the brightness control circuit in the explosion-proof lighting lamp; The current of a preset time length is used as the segmented current; each harmonic frequency is preset, and the fluctuation degree of each harmonic frequency is determined based on the discrete degree of the amplitude information and phase information of each harmonic frequency of the segmented current; the difference between the fluctuation degree of each harmonic frequency and all harmonic frequencies is analyzed to determine the power impact weight of each harmonic frequency; The amplitude information and phase information of each harmonic frequency of the segmented current are integrated, and the harmonic current of each harmonic frequency is obtained by using inverse Fourier transform; the temperature influence weight is determined according to the peak distribution characteristics and temperature distribution characteristics of the harmonic current of all segmented currents at each harmonic frequency; According to the power influence weights of all harmonic frequencies and the reactive power of the corresponding harmonic currents, combined with the temperature influence weights, the reactive compensation amount is determined, and the capacitor is selected according to the voltage of the brightness control circuit to control the reactive power generated by the brightness control circuit in the explosion-proof lighting lamp; The process of determining the temperature influence weight includes: According to the peak distribution of the harmonic current of all segment currents at each harmonic frequency, the peak sequence of each harmonic frequency is obtained; The temperature of the preset time period is divided based on the number of elements in the peak sequence to obtain an average temperature sequence; A time series decomposition algorithm is used for the temperature in a preset time period to obtain a trend sequence, and a first-order difference sequence of the trend sequence is obtained; Based on the elements of the first-order difference sequence, a temperature change index is obtained; The temperature influence weight of the explosion-proof lighting is recorded as B, and its formula is: ;in, is the maximum value of the Pearson correlation coefficient between the mean temperature series and each peak series; is the temperature change index; is the temperature at the last moment in the preset time period, It is the upper limit of the safe operating temperature of explosion-proof lighting lamps.

2. A method for controlling the brightness of an explosion-proof lighting lamp as claimed in claim 1, characterized in that: The fluctuation degree of each harmonic frequency is specifically a fusion result of the discrete degree of the amplitude information and the discrete degree of the phase information of each harmonic frequency.

3. The method for controlling the brightness of an explosion-proof lighting lamp according to claim 1, characterized in that: The power impact weight of each harmonic frequency is determined as follows: For all harmonic frequencies except the first harmonic frequency, the cumulative sum of the fluctuation degrees is calculated; based on the ratio of the fluctuation degree of each harmonic frequency except the first harmonic frequency to the cumulative sum, the power impact weight of each harmonic frequency is obtained.

4. The method for controlling the brightness of an explosion-proof lighting lamp according to claim 1, characterized in that: The peak sequence of each harmonic frequency is obtained as follows: For the harmonic current of each segment current at each harmonic frequency, the average value of the peak value of each harmonic current is obtained and recorded as the peak value mean; all the peak values ​​at each harmonic frequency are combined into a peak value sequence of each harmonic frequency.

5. The method for controlling the brightness of an explosion-proof lighting lamp as claimed in claim 1, characterized in that: The step of obtaining the average temperature sequence comprises: Obtaining the ratio of the number of temperatures in a preset time period to the number of elements in the peak sequence; If the ratio is an integer, the ratio is used as the number of segments into which the temperature of the preset time period is divided, and the temperature average of each segment after the division is calculated; the sequence composed of all temperature averages is used as the average temperature sequence; If the ratio is not an integer, then The number of temperatures divided into segments is the rounded-down value of the ratio, and all remaining elements constitute the first paragraph; among them, Represents the number of elements in the peak sequence.

6. The method for controlling brightness of explosion-proof lighting according to claim 1, characterized in that: The temperature change index is specifically the proportion of positive numbers in the first-order difference sequence.

7. The method for controlling brightness of explosion-proof lighting according to claim 1, characterized in that: The process of confirming the reactive power compensation amount is as follows: The reactive power of the harmonic current corresponding to all subharmonic frequencies is synthesized and combined with the temperature influence weight to obtain the reactive power of the harmonic; The reactive power compensation amount is recorded as , its formula form is: ; is the temperature effect weight, is the reactive power of the reactive current, is the reactive power of the harmonics.

8. The method for controlling brightness of explosion-proof lighting according to claim 1, characterized in that: The capacity of the selected capacitor is: Get the angular frequency in the brightness control circuit, recorded as ; The capacity of the capacitor is recorded as , its formula form is: ;in, is the capacitor capacity, is the reactive power compensation amount, is the voltage of the brightness control circuit.

9. An explosion-proof lighting lamp, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

Images