CN106814321A - Temperature compensation circuit for measuring battery power and hand-held lamps - Google Patents

Abstract

The invention relates to a temperature compensation electricity measuring circuit. A temperature compensated power measurement circuit, comprising: the processing module is electrically connected with the display module and the temperature detection module; the temperature detection module is used for detecting the temperature value of the battery and sending the temperature value to the processing module; the processing module is used for detecting the voltage of the battery and controlling the display module to display the electric quantity according to the temperature value, the voltage of the battery and a prestored corresponding relation table. Therefore, the problem that the residual electric quantity measured by a voltage method at different temperatures is large in error is solved. The user can know the electric quantity of the battery more accurately, the portable lamp is arranged and used more reasonably, and the use efficiency of the user is improved.

Description

Temperature compensation circuit for measuring battery power and hand-held lamps

technical field

The invention relates to the field of battery power, in particular to a circuit for measuring battery power with temperature compensation.

Background technique

The current power display technology, generally speaking, can remind customers to charge when the power is low (generally less than 20%), but this power display technology does not take into account the influence of temperature, and does not compensate for the influence of temperature . Taking lithium battery as an example, the discharge curve and discharge time of lithium battery are very different at high temperature, normal temperature and low temperature. After actual measurement, when the lithium battery is at high temperature, the voltage drops from 4.2V to 3.5V relatively slowly. The time drops quickly; at low temperature, the lithium battery drops from 4.2V to 3.5V quickly, and after reaching 3.5V, it drops slowly over time. For example, a 1700ma lithium battery at high temperature (25° to 30°) works at a current of 280mA. When the voltage drops to 3.2V, the remaining power is about 2%, and it can only work for more than ten minutes. At a low temperature of -20°, the same Lithium batteries are discharged to 3.2V under common conditions, and the remaining power is about 38%, and they can still work for 70 minutes. There is a huge difference between the two. If the influence of ambient temperature is not distinguished, there will be huge errors in measuring the power of lithium batteries by voltage method.

However, in the actual application of the current portable handheld lamps and mobile lamps using batteries, if there is a huge error in the power indicator, it is impossible to predict the actual power of the current lamp, and it is impossible to judge how long it can be used, whether it needs to be charged, etc. Problems, it is easy to cause untimely charging, affecting the use time of on-site lamps, and thus affecting work efficiency.

Contents of the invention

Based on this, it is necessary to provide a temperature-compensated circuit for measuring battery power in view of the huge error problem existing in the current voltage method for measuring battery power.

A circuit for measuring battery power with temperature compensation, characterized in that it includes: a processing module, a display module and a temperature detection module electrically connected to the processing module;

The temperature detection module is used to detect the temperature value of the battery and send the temperature value to the processing module; the processing module is used to detect the voltage of the battery and control the display module to display the power according to the temperature value, the voltage of the battery and the pre-stored correspondence table.

In one embodiment, the processing module includes a processing unit and a peripheral circuit, and the processing unit is connected to the battery through the peripheral circuit.

In one of the embodiments, the processing unit is a single-chip microcomputer; the peripheral circuit includes a first voltage dividing resistor and a second voltage dividing resistor, the first voltage dividing resistor and the second voltage dividing resistor are connected in parallel and one end is grounded, and the other end is connected to the battery; The processing unit measures the voltage of the battery through the first voltage dividing resistor and the second voltage dividing resistor.

In one of the embodiments, the processing unit pre-stores multiple correspondence tables.

In one embodiment, the multiple correspondence tables are the correspondence between the battery voltage and the battery power obtained according to the battery discharge curve, and the multiple correspondence tables are in one-to-one correspondence with a plurality of preset temperature value ranges.

In one of the embodiments, the temperature detection module is a temperature sensor.

In one of the embodiments, it further includes a voltage stabilizing module, the input terminal of the voltage stabilizing module is connected to the battery, and the output terminal of the voltage stabilizing module is connected to the processing module.

In one of the embodiments, the display module is a liquid crystal display or an LED display.

In one of the embodiments, the voltage stabilizing module is a voltage stabilizing chip.

In one embodiment, the battery power of a hand-held lamp is suitable for measurement by the above-mentioned temperature compensation circuit for measuring battery power.

The above circuit for measuring electric quantity with temperature compensation measures the temperature of the battery through the temperature detection module and sends it to the measurement module. The measurement module measures the voltage of the battery and outputs a control signal according to the pre-stored correspondence table between the battery voltage and the battery thermometer, and controls the display module to display the electric quantity , so as to solve the problem that the voltage method has a large error in measuring the remaining power at different temperatures of high and low temperatures. It enables the user to know the battery power more accurately, arranges the use of portable lamps more reasonably, and improves the user's use efficiency.

Description of drawings

Fig. 1 is a circuit principle block diagram of temperature compensation measuring battery power of an embodiment;

Fig. 2 is the voltage stabilizing circuit diagram of temperature compensation measuring battery power in the embodiment of Fig. 1;

FIG. 3 is a circuit diagram of temperature compensation measuring battery power in an embodiment shown in FIG. 1 .

detailed description

As can be seen from FIG. 1 , it is a schematic block diagram of a circuit for measuring battery power with temperature compensation according to an embodiment. As can be seen from FIG. 1 , the temperature compensation power display circuit includes: a processing module 10 , a temperature detection module 12 , and a display module 14 , and the processing module 10 is electrically connected to the temperature detection module 12 and the display module 14 .

It can also be seen from FIG. 1 that this embodiment takes the measurement of the electric quantity of a lamp battery as an example. It can be understood that the circuit for measuring electric quantity with temperature compensation can be applied to portable handheld lamps and mobile devices using batteries.

Wherein, the temperature detection module 12 is used for detecting the temperature value of the battery, and sends the detected temperature value to the processing module 10, and the processing module 10 is used for detecting the voltage of the battery and according to the received temperature value, the voltage of the battery and the corresponding relationship stored in advance The meter controls the display module 14 to display the electric quantity.

Further, the processing module 10 includes a processing unit and peripheral circuits of the processing unit (the processing unit and peripheral circuits are not shown in the figure). The processing unit pre-stores a plurality of correspondence tables, all of which are correspondence tables of battery voltage and battery power obtained according to the battery discharge curve, and each correspondence table corresponds to a different range of battery temperature values.

In this embodiment, a commonly used mobile lamp is taken as an example. The operating environment of commonly used mobile lamps is -20°C to 40°C, and they are powered by lithium batteries. Since the discharge time corresponding to the discharge curve of lithium batteries at high temperature, normal temperature and low temperature is very different, the temperature value range of -20°C to 40°C can be subdivided into -20°C to -5°C, -5°C to 15°C, There are four different temperature value ranges of 15°C to 30°C and 30°C to 40°C, and the corresponding relationship table of voltage and power corresponding to the different temperature value ranges is obtained according to the battery discharge curve.

Understandably, the battery operating temperature value range is divided into multiple intervals, and one interval corresponds to a corresponding relationship table. In this way, the more intervals are divided, the smaller the impact of temperature on the remaining battery capacity and the higher the accuracy. With the increase of interval division, the processing function of the processing unit should also increase. The division of the specific temperature range depends on the actual working environment of the electrical appliance and the relationship between the battery discharge curve and the temperature.

Preferably, the processing unit 101 is a single-chip microcomputer, the memory and processing capability of the single-chip microcomputer can meet actual needs, and the peripheral circuits of the single-chip microcomputer are flexible and simple to build.

When the temperature detection module 12 detects the temperature value of the lithium battery, and sends the temperature value to the processing module 10, the processing unit 101 is connected to the battery through the peripheral circuit, measures the voltage value of the battery, and according to the temperature value detected by the temperature detection module 12 Determine the correspondence table, find the power corresponding to the battery voltage in the correspondence table, and control the display module 14 to display the power according to the power in the correspondence table.

In this embodiment, the processing unit 101 determines the corresponding relationship table according to the temperature value detected by the temperature detection module 12. Specifically, the processing unit 101 determines the temperature value range corresponding to the temperature value detected by the temperature detection module 12, and determines that the temperature value range corresponds to The corresponding relationship table, the corresponding relationship table is the corresponding relationship table corresponding to the temperature value.

In this embodiment, the temperature detection module 12 is a temperature sensor. The display module 14 is a liquid crystal display or an LED display. Further, according to specific usage requirements, the temperature detection module 12 includes a control switch and a temperature sensor. Wherein, the control switch is used to control the timing switch of the temperature sensor, so that the temperature sensor measures the temperature of the battery regularly.

Preferably, the temperature-compensated electric quantity display circuit of this embodiment also includes a voltage stabilizing module (the stabilizing module is not shown in FIG. Regulator circuit. This embodiment takes the measurement of the power of 1 to 3 lithium batteries as an example. According to the characteristic that the voltage of 3 lithium batteries does not exceed 12.6V, the voltage stabilizing circuit is composed of chip HT7130, input capacitor C1, and output capacitor C2, which is lower than 12.6V. After the voltage of V passes through the chip HT7130, the output of the chip is Vout=3V, and the specific circuit diagram of the voltage stabilizing circuit is shown in Figure 2.

FIG. 3 is a circuit diagram of temperature compensation measuring battery power in an embodiment shown in FIG. 1 . It can be seen from Fig. 3 that in this embodiment, the temperature sensing module is specifically a temperature sensor DS18B20, the processing module is composed of a single-chip microcomputer tiny1634 and peripheral circuits of the single-chip microcomputer tiny1634, and the display module is a segmented liquid crystal display. Specifically, the peripheral circuit of the single chip microcomputer tiny1634 includes a first voltage dividing resistor R10 and a second voltage dividing resistor R11, the first voltage dividing resistor R10 and the second voltage dividing resistor R11 are connected in parallel, one end is grounded, and the other end is connected to the battery. The single chip microcomputer tiny1634 can measure the voltage of the battery through the first voltage dividing resistor R10 and the second voltage dividing resistor R11.

The temperature sensor DS18B20 has three interfaces, which are the ground port GND, the port DQ connected with the microcontroller tiny1634, and the VDD port for sensing the battery temperature.

The temperature sensor DS18B20 detects the temperature value of the battery, and the single-chip microcomputer queries the corresponding table to obtain the current power, and displays the current battery power through the display module.

In this embodiment, the segment liquid crystal display is composed of a liquid crystal screen and a driving circuit, and the driving circuit 30 is used to control the display contrast brightness of the liquid crystal screen. In this embodiment, the drive circuit 30 is a commonly used LCD drive circuit, with eight pins of COM1, COM2, COM3, COM4 and SEG1, SEG2, SEG3, and SEG4 corresponding to the IO port of the single-chip microcomputer, and the COM1 pin is passed through The piezoresistor R2 is connected to the IO port of the single-chip microcomputer tiny1634 (the IO port of the single-chip microcomputer is not shown in the figure), the other end is grounded through the voltage dividing resistor R3, the COM2 pin is connected to the IO port of the single-chip microcomputer tiny1634 through the voltage dividing resistor R4, and the other end The pin COM3 is connected to the IO port of the microcontroller tiny1634 through the voltage dividing resistor R5, the other end is grounded through the voltage dividing resistor R7, the COM4 pin is connected to the IO port of the microcontroller tiny1634 through the voltage dividing resistor R8, and the other end Grounded through the voltage divider resistor R9.

According to the driving principle of LCD, only AC voltage can be applied to the LCD pixels. The contrast of the LCD display is determined by the voltage value on the COM pin minus the voltage value on the SEG pin. When the voltage difference is greater than the saturation voltage of the LCD The pixels can be turned on, and the pixels can be turned off when the threshold voltage of the LCD is lower than the LCD threshold voltage, and the driving of the LCD is completed.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A circuit for measuring battery power with temperature compensation, comprising: a processing module, a display module and a temperature detection module electrically connected to the processing module; The temperature detection module is used to detect the temperature value of the battery and send the temperature value to the processing module; the processing module is used to detect the voltage of the battery and according to the temperature value, the voltage of the battery and the corresponding The relationship table controls the display module to display the electric quantity. 2 . The circuit for measuring battery power with temperature compensation according to claim 1 , wherein the processing module includes a processing unit and a peripheral circuit, and the processing unit is connected to the battery through the peripheral circuit. 3 . 3. The circuit for measuring battery power with temperature compensation according to claim 2, wherein the processing unit is a single-chip microcomputer; the peripheral circuit includes a first voltage dividing resistor and a second voltage dividing resistor, and the first dividing resistor The piezoresistor and the second voltage dividing resistor are connected in parallel with one end connected to the ground and the other end connected to the battery; the processing unit measures the voltage of the battery through the first voltage dividing resistor and the second voltage dividing resistor. 4 . The circuit for measuring battery power with temperature compensation according to claim 3 , wherein the processing unit pre-stores a plurality of correspondence tables. 5. The circuit for measuring battery power with temperature compensation according to claim 4, wherein the plurality of correspondence tables are the correspondence between battery voltage and battery power obtained according to the battery discharge curve, and the plurality of correspondence tables The relational table is in one-to-one correspondence with a plurality of preset temperature value ranges. 6. The circuit for measuring battery power with temperature compensation according to claim 1, wherein the temperature detection module is a temperature sensor. 7. The circuit for measuring battery power with temperature compensation according to claim 1, further comprising a voltage stabilizing module, the input end of the voltage stabilizing module is connected to the battery, and the output end of the voltage stabilizing module is connected to the processing module. 8. The circuit for measuring battery power with temperature compensation according to claim 1, wherein the display module is a liquid crystal display or an LED display. 9. The circuit for measuring battery power with temperature compensation according to claim 7, wherein the voltage stabilizing module is a voltage stabilizing chip. 10. A hand-held lamp, comprising a battery, characterized in that it further comprises a circuit for measuring battery power with temperature compensation according to any one of claims 1 to 9.