A voltage output adjustment device for high-precision high-power shunt resistor

Abstract

The invention is applicable to the technical field of resistor production, and provides a voltage output adjustment device for a high-precision high-power shunt resistor, which is connected to a high-power shunt resistor R1, one end of which is provided with a current terminal C1 and a voltage terminal V1, and the other end of which is provided with a current terminal C2 and a voltage terminal V2. The voltage output adjustment device comprises a resistor R2, a resistor R3, a resistor R4 and an adjustable resistor W, one end of the resistor R2 is connected to the voltage terminal V1, and the other end is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, the other end of the resistor R4 is connected to the voltage terminal V2, one end of the adjustable resistor W is connected to a wire between the resistor R2 and the resistor R3, and the other end is connected to a wire between the resistor R3 and the resistor R4, the wire between the resistor R2 and the voltage terminal V1 is connected to an output terminal P1, and the center of the adjustable resistor W is connected to an output terminal P2; the overall structure is simple, the adjustment is convenient, and the precision is high.

Description

Technical Field

[0001] The invention belongs to the technical field of resistor production, and in particular relates to a voltage output adjustment device for a high-precision and high-power shunt resistor. Background Art

[0002] With the vigorous development of new energy electric vehicles, charging piles, photovoltaic and wind power generation, high-precision high-power shunt resistors have been widely used, and the resistance values ​​used have generally reached the micro-ohm level. Due to the small resistance value and high precision requirements, the current main domestic production method is to leave a certain negative margin in the semi-finished product, and then manually adjust it to the required resistance value. In the existing resistor adjustment process, not only is the labor intensity high, but the heat generated during the filing process causes measurement errors. If the adjusted resistance value is biased beyond the error range, the product will be scrapped. If the resistance value of the semi-finished product is biased beyond the error range, it will also be scrapped.

[0003] Therefore, the prior art has defects. Summary of the invention

[0004] The purpose of the present invention is to overcome the disadvantage of the prior art that the resistance value is difficult to adjust, and to provide a voltage output adjustment device for a high-precision high-power shunt resistor.

[0005] The present invention is implemented as follows: a voltage output adjustment device for a high-precision high-power shunt resistor, connected to a high-power shunt resistor R1, one end of the high-power shunt resistor R1 is provided with a current terminal C1 and a voltage terminal V1, and the other end is provided with a current terminal C2 and a voltage terminal V2, the voltage output adjustment device includes a resistor R2, a resistor R3, a resistor R4 and an adjustable resistor W, one end of the resistor R2 is connected to the voltage terminal V1, and the other end is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the voltage terminal V2, one end of the adjustable resistor W is connected to the wire between the resistor R2 and the resistor R3, and the other end is connected to the wire between the resistor R3 and the resistor R4, the wire between the resistor R2 and the voltage terminal V1 is connected to the output terminal P1, and the center of the adjustable resistor W is connected to the output terminal P2.

[0006] Further, the interconnected resistors R2, R3 and R4 are located at a first resistance wire with a fixed resistance value, the two ends of the first resistance wire are respectively connected to the voltage terminal V1 and the voltage terminal V2, the first resistance wire is connected to an electric wire, the connection point between the electric wire and the first resistance wire is the adjustable resistor W, and the output terminal P2 is connected to the connection point. Further, the resistors R2, R3 and R4 are three length segments of a second resistance wire with a certain resistance value divided into three length segments in proportion, a third resistance wire is connected to the length segment of the resistor R3, the third resistance wire is the adjustable resistor W, and the output terminal P2 is connected to the third resistance wire.

[0007] The present invention provides a high-precision high-power shunt resistor voltage output adjustment device. When the high-power shunt resistor R1 is energized through the current terminal C1 and the current terminal C2 at both ends, a voltage is generated on the voltage terminal V1 and the voltage terminal V2 at both ends. Since the resistance value of the high-power shunt resistor R1 has a certain positive margin in the semi-finished product, the voltages at both ends of the resistor R2, the resistor R3 and the resistor R4 are relatively large. According to the required output voltage, the ratio of the resistor R2, the resistor R3 and the resistor R4 is calculated and selected so that the voltage drop on the resistor R3 is within a certain adjustment range. Then, a high-precision output value is adjusted through the adjustable resistor W, so that the voltage output adjustment of the high-power shunt resistor R1 can be realized. The structure is simple, the adjustment is convenient, the precision is high, and the semi-finished product produced will not be scrapped due to the resistance value error. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0009] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0010] Figure 1 The present invention provides a circuit diagram of a voltage output adjustment device for a high-precision high-power shunt resistor.

[0011] Figure 2 It is a circuit diagram of a second embodiment of a voltage output adjustment device for a high-precision and high-power shunt resistor provided by the present invention.

[0012] Figure 3It is a circuit diagram of a third embodiment of a voltage output adjustment device for a high-precision and high-power shunt resistor provided by the present invention. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0014] See also Figure 1-Figure 3 , is a high-precision high-power shunt resistor voltage output adjustment device disclosed in the invention, which is connected to the high-power shunt resistor R1. One end of the high-power shunt resistor R1 is provided with a current terminal C1 and a voltage terminal V1, and the other end is provided with a current terminal C2 and a voltage terminal V2. The high-power shunt resistor R1 is connected to a power supply through the current terminals C1 and C2 at both ends to be energized.

[0015] The voltage output adjustment device includes a resistor R2, a resistor R3, a resistor R4 and an adjustable resistor W. Figure 1 As shown, the adjustable resistor W is a sliding rheostat, that is, the adjustable resistor W has a central sliding arm, and the resistance value of the adjustable resistor W can be adjusted by sliding the central sliding arm. One end of the resistor R2 is connected to the voltage terminal V1, and the other end is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the voltage terminal V2, that is, the resistor R2, the resistor R3 and the resistor R4 are connected in series in sequence. One end of the adjustable resistor W is connected to the wire between the resistor R2 and the resistor R3, and the other end is connected to the wire between the resistor R3 and the resistor R4, that is, the adjustable resistor W is connected in parallel with the resistor R3. The wire between the resistor R2 and the voltage terminal V1 is connected to the output terminal P1, and the center of the adjustable resistor W, that is, the central sliding arm, is connected to the output terminal P2. Among them, the output terminal P1 is the voltage output common terminal of the high-power shunt resistor R1.

[0016] When the high-power shunt resistor R1 is energized through the current terminals C1 and C2 at both ends, a voltage is generated at the voltage terminals V1 and V2 at both ends. Since the resistance value of the high-power shunt resistor R1 has a certain positive margin in the semi-finished product, the voltage across the resistors R2, R3 and R4 is relatively large. According to the required output voltage, the ratio of the resistors R2, R3 and R4 is calculated and selected so that the voltage drop on the resistor R3 is within a certain adjustment range, and then the high-precision output value is adjusted through the adjustable resistor W, so that the voltage output adjustment of the high-power shunt resistor R1 can be achieved.

[0017] This embodiment uses an example to illustrate the voltage output adjustment of the high-power shunt resistor R1: if a 750A, 75mV shunt needs to be produced, and the resistance value accuracy is required to be ±0.5, then the resistance value of the high-power shunt resistor needs to be in the range of 0.0995mΩ-0.1005mΩ, and the output voltage value of the output terminal P1 needs to be in the range of 74.625mV-75.375mV. If the semi-finished product of the high-power shunt resistor is 0.1030mΩ, the output voltage of the output terminal P1 is 77.25mV. Since the detection voltage is at the millivolt level, the ports of the detection device are all in a high impedance state, so the resistance values ​​of the resistor R2, the resistor R3, the resistor R4 and the adjustable resistor W can be selected within a wider range. In this example, the resistor R2 is selected as 15Ω, the resistor R3 is selected as 1Ω, the resistor R4 is selected as 0Ω (short circuit), and the adjustable resistor W is selected as 100Ω. By calculation, it can be obtained that the voltage across the resistor R3 is 4.828V, and the voltage value between the resistor R2 and the resistor R3 is 72.422mV. In this way, by adjusting the adjustable resistor W, the output voltage of P1 and P2 can be changed within the range of 72.422mV and 77.25mV. Therefore, a high-precision output voltage of 75mV can be adjusted. If we need an output voltage of 50mV, R2 can be selected as 10Ω, R3 can be selected as 1Ω, R4 can be selected as 5Ω, and W can be selected as 100Ω. By calculation, it can be obtained that by adjusting the adjustable resistor W, the output voltage of the output terminal P1 and the output terminal P2 can be changed within the range of 48.281mV and 53.109mV, that is, a high-precision output voltage of 50mV can be adjusted. In summary, the voltage output adjustment device can adjust any required high-precision output value within the maximum output voltage range of the high-power shunt resistor R1 through the resistance ratio distribution of the resistor R2, the resistor R3, the resistor R4 and the adjustable resistor W to meet different needs. It has a simple structure, convenient adjustment, high precision, and the semi-finished products produced will not be scrapped due to resistance errors.

[0018] As a second embodiment of this solution, Figure 2 As shown, the position of the resistors R2, R3 and R4 connected to each other is a first resistor wire with a fixed resistance value, that is, the resistors R2, R3 and R4 connected in series can be replaced by the first resistor wire with a fixed resistance value, the two ends of the first resistor wire are respectively connected to the voltage terminal V1 and the voltage terminal V2, the first resistor wire is connected with a wire, and the connection point between the wire and the first resistor wire is the adjustable resistor W, that is, in this embodiment, the resistance value of the adjustable resistor W is also fixed, and the connection between the wire and the first resistor wire can be a welding connection, because there is no terminal on the first resistor wire, and the use of welding connection can improve the stability of the connection to a limited extent, and the output terminal P2 is connected to the wire. Since the first resistor wire has a fixed resistance value, in practical applications, the scheme in the above embodiment can be adopted if the voltage adjustment accuracy is not high, and the structure is simpler, which can ensure the adjustment of the voltage while greatly reducing the production cost.

[0019] As the third embodiment of this solution, Figure 3 As shown, the resistor R2, the resistor R3 and the resistor R4 are three length segments of a second resistor wire with a certain resistance value divided into three length segments in proportion, and different lengths represent different resistance values. A third resistor wire is connected in parallel to the length segment of the resistor R3, and the resistance value of the third resistor wire is greater than the resistance value of the resistor R3. The third resistor wire is equivalent to the adjustable resistor W. The output terminal P2 is connected to the third resistor wire, which is equivalent to the output terminal P2 being connected to the central sliding arm of the adjustable resistor W. After calculating the resistance value of the adjustable resistor W, the output terminal P2 is connected to the third resistor wire by welding to confirm the resistance value of the adjustable resistor W. The second resistance wire is divided into three segments according to different length segment ratios, so that the resistance values ​​of the resistors R2, R3 and R4 can be adjusted to a certain extent. The resistance values ​​of the resistors R2, R3, R4 and the adjustable resistor W can be selected more accurately than the second embodiment. While controlling the cost, the voltage adjustment accuracy is also higher than the second embodiment. In practical applications, those who have certain requirements on the voltage adjustment accuracy can select the above embodiment.

[0020] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-precision high-power shunt resistor voltage output adjustment device, connected to a high-power shunt resistor R1, wherein one end of the high-power shunt resistor R1 is provided with a current terminal C1 and a voltage terminal V1, and the other end is provided with a current terminal C2 and a voltage terminal V2, characterized in that: The voltage output adjustment device includes a resistor R2, a resistor R3, a resistor R4 and an adjustable resistor W, one end of the resistor R2 is connected to the voltage terminal V1, and the other end is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the voltage terminal V2, one end of the adjustable resistor W is connected to the wire between the resistor R2 and the resistor R3, and the other end is connected to the wire between the resistor R3 and the resistor R4, the wire between the resistor R2 and the voltage terminal V1 is connected to the output terminal P1, and the center of the adjustable resistor W is connected to the output terminal P2.

2. The voltage output adjustment device of a high-precision high-power shunt resistor according to claim 1, characterized in that: The position of the interconnected resistors R2, R3 and R4 is a first resistance wire with a fixed resistance, the two ends of the first resistance wire are respectively connected to the voltage terminal V1 and the voltage terminal V2, the first resistance wire is connected to an electric wire, the connection point between the electric wire and the first resistance wire is the adjustable resistor W, and the output terminal P2 is connected to the connection point.

3. The voltage output adjustment device of a high-precision high-power shunt resistor according to claim 1, characterized in that: The resistors R2, R3 and R4 are a second resistance wire with a certain resistance value, which divides the resistance value into three length segments in proportion. A third resistance wire is connected to the length segment of the resistor R3. The third resistance wire is the adjustable resistor W. The output terminal P2 is connected to the third resistance wire.

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