Photovoltaic measuring instrument

Abstract

The utility model belongs to the technical field of photovoltaic measurement, and particularly relates to a photovoltaic measuring instrument, which comprises a power measuring device, a voltage measuring device and a power output device, and is characterized in that the power measuring device comprises a variable load circuit, a current acquisition circuit and a voltage acquisition circuit; the dip angle measuring device comprises a dip angle measuring module used for generating magnetic parameters and space parameters, and the processing device is used for generating dip angle parameters according to the magnetic parameters and the space parameters; the battery measuring device comprises a battery electric quantity detection circuit which is used for collecting a battery voltage signal of a photovoltaic module to be measured and outputting the battery voltage signal to a processing device; and the display device is used for displaying measurement results of the power measurement device, the inclination angle measurement device and the battery measurement device. On the basis of having a photovoltaic module power measurement function, the equipment integrates a photovoltaic module inclination angle measurement function and a battery measurement function, the application range of the equipment is obviously expanded, and convenience is provided for installation of the photovoltaic module, so that various test requirements can be met, and the measurement functions are comprehensive.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic module measurement, and particularly relates to a photovoltaic measuring instrument. BACKGROUND

[0002] The photovoltaic measuring instrument is used to evaluate the conversion efficiency, power output and other key parameters of the photovoltaic cell by measuring the current-voltage characteristic curve of the photovoltaic cell under different light and temperature conditions. In the related art, the existing photovoltaic measuring instrument has relatively single function and can only test the basic power parameters of the photovoltaic panel, such as voltage and current. In particular, in the installation and test process of the photovoltaic panel, it is crucial to determine and record the optimal light angle, but the existing product lacks the tilt angle test function.

[0003] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the present disclosure, and therefore can include information that does not constitute prior art known to those skilled in the art. SUMMARY

[0004] In view of at least one of the above technical problems, the present application provides a photovoltaic measuring instrument.

[0005] The present application provides a photovoltaic measuring instrument, comprising: a power measuring device, a tilt angle measuring device, a cell measuring device and a processing device;

[0006] The power measuring device comprises a variable load circuit, a current acquisition circuit and a voltage acquisition circuit. The variable load circuit is used to change the load of itself to adjust the current in the photovoltaic module to be measured. The current acquisition circuit is used to acquire the current signal in the photovoltaic module to be measured. The voltage acquisition circuit is used to acquire the voltage signal in the photovoltaic module to be measured. The processing device is used to obtain the circuit parameters of the photovoltaic module according to the current signal and the voltage signal.

[0007] The tilt angle measuring device comprises a tilt angle measuring module. The tilt angle measuring module is used to generate magnetic force parameters and space parameters. The processing device is used to generate tilt angle parameters according to the magnetic force parameters and the space parameters.

[0008] The cell measuring device comprises a cell power detection circuit. The cell power detection circuit is used to acquire the cell voltage signal of the photovoltaic module to be measured and output to the processing device.

[0009] The display device is connected with the processing device and is used to display the measurement results of the power measuring device, the tilt angle measuring device and the cell measuring device.

[0010] The technical scheme has at least one of the following advantages or beneficial effects: the device integrates the inclination measurement function and the battery measurement function on the basis of the photovoltaic module power measurement function, significantly expands the application range of the device, provides convenience for photovoltaic module installation, and thus can meet various testing requirements and measurement functions are comprehensive.

[0011] In some possible implementation manners, the variable load circuit comprises: a PWM control circuit and a variable load controlled circuit, the PWM control circuit is connected with the variable load controlled circuit, the PWM control circuit is configured to provide a PWM signal to the variable load controlled circuit, and the variable load controlled circuit is connected with the photovoltaic module to be tested and configured to adjust the load according to the PWM signal, so as to adjust the current in the photovoltaic module to be tested.

[0012] In some possible implementation manners, the variable load controlled circuit comprises: a first adjusting unit, a first variable resistance unit, a second adjusting unit, a second variable resistance unit, a third adjusting unit and a third variable resistance unit, the non-inverting input terminals of the first adjusting unit, the second adjusting unit and the third adjusting unit are connected with the PWM control circuit, the first end of the first variable resistance unit is connected with the first adjusting unit, the second end of the first variable resistance unit is connected with the photovoltaic module to be tested, the first end of the second variable resistance unit is connected with the second adjusting unit, the second end of the second variable resistance unit is connected with the photovoltaic module to be tested, the first end of the third variable resistance unit is connected with the third adjusting unit, the second end of the third variable resistance unit is connected with the photovoltaic module to be tested, and the third ends of the first variable resistance unit, the second variable resistance unit and the third variable resistance unit are connected in common.

[0013] In some possible implementation manners, the first variable resistance unit, the second variable resistance unit and the third variable resistance unit are MOS tubes.

[0014] In some possible implementation manners, the first adjusting unit, the second adjusting unit and the third adjusting unit are operational amplifiers.

[0015] In some possible implementation manners, the inclination measurement module is a chip integrating a magnetometer and an accelerometer.

[0016] In some possible implementation manners, the inclination measurement module is in communication connection with the processing device through IIC.

[0017] In some possible implementation manners, the battery power detection circuit comprises: an analog switch and a battery gear circuit, the battery gear circuit is connected between the photovoltaic module to be tested and the processing device, the analog switch is controlled by the processing device and selectively conducts one branch of the battery gear circuit.

[0018] In some possible implementation manners, the battery gear circuit comprises a first gear branch, a second gear branch and a third gear branch.

[0019] In some possible implementation manners, the analog switch has a first control end and a second control end connected with the processing device respectively.

[0020] When the first control end is low and the second control end is high, the analog switch is connected with the first gear branch.

[0021] When the first control end is high and the second control end is low, the analog switch is connected with the second gear branch.

[0022] When the first control end is high and the second control end is high, the analog switch is connected with the third gear branch.

[0023] The application will be further described below in conjunction with the drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0025] Figure 1 The schematic diagram of the photovoltaic measuring instrument provided by the embodiment of the present application;

[0026] Figure 2 The schematic diagram of the power measuring device provided by the embodiment of the present application;

[0027] Figure 3 The schematic diagram of the variable load circuit provided by the embodiment of the present application;

[0028] Figure 4 The circuit diagram of the variable load circuit provided by the embodiment of the present application;

[0029] Figure 5 The circuit diagram of the battery power detection circuit provided by the embodiment of the present application; DETAILED DESCRIPTION

[0030] In order to make the above objectives, characteristics and advantages of the present application more apparent, more comprehensible, specific embodiments of the present application are described in detail below with reference to the drawings. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many different ways other than those described herein, and one of ordinary skill in the art can make similar improvements without departing from the spirit of the present application, and therefore the present application is not limited to the specific embodiments disclosed below.

[0031] As shown in Figures 1 to 5 The present embodiment provides a photovoltaic measuring instrument, comprising: a power measuring device 100, an inclination measuring device 200, a battery power measuring device 300 and a processing device. The present device integrates the inclination measuring function and the battery measuring function of the photovoltaic module on the basis of the photovoltaic module power measuring function, significantly expands the application range of the device, provides convenience for the installation of the photovoltaic module, and thus can meet various testing requirements and has comprehensive measuring functions. In addition, the present device has the convenient inclination measuring function, which facilitates finding and recording the inclination corresponding to the maximum power; at the same time, the special battery measuring function can identify the power of different batteries; the photovoltaic power measuring function can quickly and conveniently measure the maximum power of the photovoltaic panel.

[0032] It can be understood that the photovoltaic module is a photovoltaic solar device, which includes but is not limited to a photovoltaic panel and a photovoltaic battery.

[0033] The photovoltaic measuring instrument in the present embodiment is described below.

[0034] As shown in Figures 1 to 5 The power measuring device 100 comprises: a variable load circuit 110, a current acquisition circuit 120 and a voltage acquisition circuit 130. The variable load circuit 110 is used to change the current in the photovoltaic module to be measured. The current acquisition circuit 120 is used to acquire the current signal in the photovoltaic module to be measured. The voltage acquisition circuit 130 is used to acquire the voltage signal in the photovoltaic module to be measured. The processing device is used to obtain the circuit parameters of the photovoltaic module according to the current signal and the voltage signal.

[0035] In actual application, the variable load circuit 110 is connected to the photovoltaic module, thereby achieving the function of changing the current in the photovoltaic module to be measured. The current acquisition circuit 120 is used to acquire the current signal in the photovoltaic module to be measured. The voltage acquisition circuit 130 is used to acquire the voltage signal in the photovoltaic module to be measured. The processing device receives the current signal and the voltage signal, and calculates the circuit parameters of the photovoltaic module.

[0036] It can be understood that the circuit parameters of the photovoltaic module include but are not limited to the open-circuit voltage, the short-circuit voltage and the maximum power point of the photovoltaic battery.

[0037] The inclination measuring device 200 comprises an inclination measuring module for generating magnetic parameters and spatial parameters, and a processing device for generating inclination parameters according to the magnetic parameters and the spatial parameters.

[0038] The inclination measuring module is a chip integrating a magnetometer and an accelerometer. The magnetometer is responsible for measuring magnetic field data and determining the heading angle by measuring the horizontal component of the geomagnetic field, which is the angle between the current direction and magnetic north. In the northern hemisphere, the geomagnetic field direction is tilted towards the ground, and the X-axis and Y-axis data of the magnetometer can be used to calculate the heading angle. When the device is rotated horizontally, the heading angle changes between 0°-360°. The accelerometer is used to measure the inclination.

[0039] The inclination measuring module is connected to the processing device through IIC. The gravity distribution and magnetic field data in three-dimensional space are transmitted to the processing device through IIC by the signal processing and ADC data acquisition part. The processing device generates inclination parameters according to the magnetic parameters and the spatial parameters, wherein the magnetic parameters are collected by the magnetometer, and the spatial parameters are collected by the accelerometer.

[0040] In actual use, first place the photovoltaic measuring instrument horizontally and calibrate the angle to ensure the accuracy of the measurement. After calibration, when the maximum power point of the photovoltaic panel is measured, simply place the photovoltaic measuring instrument parallel to the photovoltaic panel, and the optimal inclination angle of the photovoltaic panel can be read and recorded on the LCD screen. This process simplifies the operation steps and improves the convenience and accuracy of the measurement.

[0041] In addition, the inclination measuring module may encounter various errors during measurement, including sensitivity error, zero point bias, non-linear error, and temperature-induced error. To improve the accuracy of the measurement, the following calibration measures can be taken: First, place the photovoltaic measuring instrument on a known horizontal surface and adjust the zero point of the inclination measuring module to eliminate the zero point bias error. Second, by calibrating the photovoltaic measuring instrument at different temperatures and establishing a temperature compensation model, the influence of temperature changes on the measurement results can be reduced. In addition, linearizing the output data of the inclination measuring device 200 using software algorithms helps to reduce non-linear errors.

[0042] The battery power measuring device 300 comprises a battery power detection circuit for collecting the battery voltage signal of the photovoltaic module to be measured and outputting to the processing device.

[0043] In actual application, the battery power detection circuit collects the battery voltage signal of the photovoltaic module to be measured and outputs it to the processing device, and then displays it on the LCD screen. When the power is sufficient, the LCD screen displays "GOOD", when the power is low, it displays "LOW", and when the power is exhausted, it displays "BAD". When the power display is "BAD", it means that the battery is not available.

[0044] A display device connected to the processing device, for displaying the measurement results of the power measuring device, the inclination measuring device, and the battery measuring device. The display device includes, but is not limited to, an LCD.

[0045] As shown in FIG. 1, in some embodiments, the variable load circuit 110 includes a PWM control circuit 111 and a variable load controlled circuit 112. The PWM control circuit 111 is connected to the variable load controlled circuit 112, and the PWM control circuit 111 is configured to provide a PWM signal to the variable load controlled circuit 112. The variable load controlled circuit 112 is connected to the photovoltaic module to be tested, and the variable load controlled circuit 112 is configured to adjust the load according to the PWM signal, thereby adjusting the current in the photovoltaic module to be tested. Figures 1 to 5 First, the load of the variable load controlled circuit 112 is adjusted by the PWM signal, thereby adjusting the current in the photovoltaic module to be tested. The PWM control method can achieve high-precision current adjustment, because the duty cycle of the PWM signal can be accurately controlled, and the change of the duty cycle can linearly change the equivalent resistance of the load, thereby finely adjusting the current size in the photovoltaic module. For example, when performing maximum power point tracking (MPPT) test on the photovoltaic module, accurate current adjustment helps to quickly and accurately find the maximum power output point of the photovoltaic module. In addition, the resolution of PWM control is higher, and PWM control can achieve continuous current adjustment in a wide range, which is very beneficial for studying the performance characteristics of the photovoltaic module under different working currents.

[0046] Secondly, due to the flexibility of PWM signal control, the variable load controlled circuit 112 can quickly respond to the control signal and efficiently adjust the load. This enables the entire test circuit to complete the performance test of the photovoltaic module under different load conditions in a short time, thereby improving the test efficiency.

[0047] Thirdly, the PWM adjustment method can avoid damage to the photovoltaic module due to overcurrent and other abnormal conditions during the test. The PWM control circuit can accurately control the rising and falling speed of the current according to the preset parameters. For example, when it is found that the current has a tendency to exceed the safe range, the duty cycle of the PWM signal can be quickly adjusted to reduce the load current, thereby protecting the photovoltaic module. The variable load controlled circuit 112 is connected to the photovoltaic module to be tested, and this connection mode enables the load adjustment process to be closely matched with the photovoltaic module. When testing the limit parameters such as short-circuit current of the photovoltaic module, the load can be gradually changed to approach the short-circuit state by gradually changing the PWM signal, rather than being directly short-circuited, thereby reducing the impact on the photovoltaic module and prolonging the service life of the photovoltaic module.

[0048]

[0049] Figures 1 to 5 ​​As shown, in some embodiments, the variable load control circuit 112 includes: a first regulating unit U1-C, a first variable resistance unit Q1, a second regulating unit U1-B, a second variable resistance unit Q4, a third regulating unit U1-A and a third variable resistance unit Q6, the positive input terminals of the first regulating unit U1-C, the second regulating unit U1-B and the third regulating unit U1-A are connected with the PWM control circuit 111, the first end of the first variable resistance unit Q1 is connected with the first regulating unit U1-C, the second end of the first variable resistance unit Q1 is connected with the photovoltaic module to be tested, the first end of the second variable resistance unit Q4 is connected with the second regulating unit U1-B, the second end of the second variable resistance unit Q4 is connected with the photovoltaic module to be tested, the first end of the third variable resistance unit Q6 is connected with the third regulating unit U1-A, the second end of the third variable resistance unit Q6 is connected with the photovoltaic module to be tested, and the third ends of the first variable resistance unit Q1, the second variable resistance unit Q4 and the third variable resistance unit Q6 are connected in common.

[0050] Specifically, the first variable resistance unit Q1, the second variable resistance unit Q4 and the third variable resistance unit Q6 are MOS tubes.

[0051] Specifically, the first regulating unit U1-C, the second regulating unit U1-B and the third regulating unit U1-A are operational amplifiers.

[0052] The first regulating unit U1-C controls the first variable resistance unit Q1, the second regulating unit U1-B controls the second variable resistance unit Q4, and the third regulating unit U1-A controls the third variable resistance unit Q6. Since the control modes of the first regulating unit U1-C, the second regulating unit U1-B and the third regulating unit U1-A are the same, the first regulating unit U1-C controlling the first variable resistance unit Q1 is taken as an example for description.

[0053] In actual application, the first regulating unit U1-C receives the PWM signal and amplifies it, and then outputs it to the first variable resistance unit Q1. The voltage of the gate-source of the first variable resistance unit Q1 changes, so that the first variable resistance unit Q1 is in a variable resistance region and has a certain drain-source resistance.

[0054] For example, when the duty ratio of the PWM signal increases, the output voltage of the first regulating unit U1-C increases, and the voltage of the gate-source of the first variable resistance unit Q1 increases. With the increase of the voltage of the gate-source of the first variable resistance unit Q1, the drain-source resistance of the first variable resistance unit Q1 decreases, which means that the current passing through the first variable resistance unit Q1 increases, thereby changing the voltage of the load connected with the first variable resistance unit Q1.

[0055] As Figures 1 to 5As shown in some embodiments, the battery power detection circuit 300 includes an analog switch U15 and a battery level circuit 310, the battery level circuit is connected between the photovoltaic module to be measured and the processing device, the analog switch U15 is controlled by the processing device to selectively conduct with a branch of the battery level circuit. Through the control of the processing device, the level switching is completed, and different voltage range measurement is realized.

[0056] As shown in some embodiments, the battery level circuit includes a first level branch 311, a second level branch 312 and a third level branch. Figures 1 to 5

[0057] The first level branch 311 is used for measuring 1.5V battery level, and the first level branch 311 has a first load resistor R61 with a resistance of 30Ω. When the analog switch U15 is connected with the first level branch 311, if the battery voltage reaches or exceeds 1.31V, the LCD screen will display "GOOD", indicating that the battery power is in the best state. When the battery voltage is between 1.3V and 0.95V, the LCD screen displays "LOW", meaning that the battery power is low. If the battery voltage drops to 0.94V or below, the LCD screen will display "BAD", indicating that the battery cannot be used any more.

[0058] The second level branch 312 is used for measuring 9V battery level, and the second level branch 312 has a second load resistor R60 with a resistance of 900Ω. When the measured battery voltage is ≥7.8V, the LCD displays GOOD, indicating that the battery power is in the best state. When the battery voltage is in the middle value of 7.7V-5.7V, the LCD displays "LOW", indicating that the battery power is in a low power state. If the measured battery voltage drops to ≤5.6V, the LCD displays BAD state, indicating that the battery cannot be used any more.

[0059] The third level branch 313 is used for measuring 12V battery level, and the third level branch 313 has a third load resistor R63 with a resistance of 240Ω. When the measured battery voltage is ≥10.5V, the LCD displays GOOD, indicating that the battery power is in the best state. When the battery voltage is in the middle value of 10.4V-7.6V, the LCD displays "LOW", indicating that the battery power is in a low power state. If the measured battery voltage drops to ≤7.5V, the LCD displays BAD state, indicating that the battery cannot be used any more.

[0060] As shown in some embodiments, the battery level circuit includes a first level branch 311, a second level branch 312 and a third level branch. Figures 1 to 5 ​As shown, in some embodiments, the analog switch U15 has a first control terminal and a second control terminal connected with the processing device respectively; when the first control terminal is low and the second control terminal is high, the analog switch U15 is connected with the first gear branch 311; when the first control terminal is high and the second control terminal is low, the analog switch U15 is connected with the second gear branch 312; when the first control terminal is high and the second control terminal is high, the analog switch U15 is connected with the third gear branch 313.

[0061] In the description of the present application, it is to be understood that the terms "first", "second", "third" and the like, merely identify features being described and do not imply or imply relative importance or a number of the features being indicated. Thus, a feature with a "first", "second", "third" designation can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0062] In the embodiments of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0063] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Any skilled person in the art can make many possible changes and modifications to the technical solutions of the present application, or modify equivalent embodiments, without departing from the scope of the technical solutions of the present application. Therefore, any equivalent changes made according to the shape, structure and principle of the present application, without departing from the scope of the technical solutions of the present application, should be covered by the protection scope of the present application.

Claims

1. A photovoltaic measuring instrument, characterized in that: include: Power measuring device, tilt measuring device, battery measuring device and processing device; The power measurement device includes: a variable load circuit, a current acquisition circuit, and a voltage acquisition circuit. The variable load circuit is used to change its own load to adjust the current in the photovoltaic module to be tested. The current acquisition circuit is used to collect the current signal of the photovoltaic module to be tested. The voltage acquisition circuit is used to collect the voltage signal of the photovoltaic module to be tested. The processing device is used to obtain the circuit parameters of the photovoltaic module according to the current signal and the voltage signal. The inclination measurement device includes: an inclination measurement module, the inclination measurement module is used to generate magnetic parameters and spatial parameters, and the processing device is used to generate the inclination parameters according to the magnetic parameters and the spatial parameters; The battery measuring device includes: a battery power detection circuit, which is used to collect the battery voltage signal of the photovoltaic module to be tested and output it to the processing device; The display device is connected to the processing device and is used to display the measurement results of the power measuring device, the tilt measuring device, and the battery measuring device.

2. The photovoltaic measuring instrument according to claim 1, characterized in that: The variable load circuit includes: a PWM control circuit and a variable load controlled circuit, the PWM control circuit is connected to the variable load controlled circuit, the PWM control circuit is used to provide a PWM signal to the variable load controlled circuit, the variable load controlled circuit is connected to the photovoltaic component to be tested, and the variable load controlled circuit is used to adjust the load according to the PWM signal, thereby adjusting the current in the photovoltaic component to be tested.

3. The photovoltaic measuring instrument according to claim 2, characterized in that: The variable load controlled circuit includes: a first adjustment unit, a first variable resistance unit, a second adjustment unit, a second variable resistance unit, a third adjustment unit, and a third variable resistance unit. The non-inverting input ends of the first adjustment unit, the second adjustment unit, and the third adjustment unit are all connected to the PWM control circuit. The first end of the first variable resistance unit is connected to the first adjustment unit, and the second end of the first variable resistance unit is connected to the photovoltaic component under test. The first end of the second variable resistance unit is connected to the second adjustment unit, and the second end of the second variable resistance unit is connected to the photovoltaic component under test. The first end of the third variable resistance unit is connected to the third adjustment unit, and the second end of the third variable resistance unit is connected to the photovoltaic component under test. The third ends of the first variable resistance unit, the second variable resistance unit, and the third variable resistance unit are connected in common.

4. The photovoltaic measuring instrument according to claim 3, characterized in that: The first variable resistance unit, the second variable resistance unit, and the third variable resistance unit are all MOS tubes.

5. The photovoltaic measuring instrument according to claim 3, characterized in that: The first regulating unit, the second regulating unit, and the third regulating unit are all operational amplifiers.

6. The photovoltaic measuring instrument according to claim 1, characterized in that: The tilt angle measurement module is a chip integrating a magnetometer and an accelerometer.

7. The photovoltaic measuring instrument according to claim 1, characterized in that: The tilt angle measurement module is communicatively connected to the processing device via IIC.

8. The photovoltaic measuring instrument according to claim 1, characterized in that: The battery power detection circuit includes: an analog switch and a battery gear circuit. The battery gear circuit is connected between the photovoltaic component to be tested and the processing device. The analog switch is controlled by the processing device and selectively conducts with a branch of the battery gear circuit.

9. The photovoltaic measuring instrument according to claim 8, characterized in that: The battery gear circuit includes a first gear branch, a second gear branch and a third gear branch.

10. The photovoltaic measuring instrument according to claim 9, characterized in that: The analog switch has a first control terminal and a second control terminal respectively connected to the processing device; When the first control terminal is at a low level and the second control terminal is at a high level, the analog switch is connected to the first gear branch; When the first control terminal is at a high level and the second control terminal is at a low level, the analog switch is connected to the second gear branch; When the first control terminal is at a high level and the second control terminal is at a high level, the analog switch is connected to the third gear branch.

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