A standard for measuring a capacitance loss tangent in the range of 0.0001 to 10

Abstract

The application discloses a standard device for measuring the tangent of a capacitance loss angle in the range of 0.0001-10, comprising a first and a second rotary switch, a capacitor array, a resistor array, a capacitor relay array, a resistor relay array, a power supply, a high-level and a low-level measuring port, a measuring loop being formed between the high-level and the low-level measuring port, and the power supply being connected with the first and the second rotary switch; the power supply is controlled by the first rotary switch to supply power to the capacitor relay array, and one of the capacitors is connected to the measuring loop; the power supply is controlled by the second rotary switch to supply power to the resistor relay array, and one or more of the resistors are connected to the measuring loop; the capacitors and the resistors connected to the measuring loop are controlled by the first and the second rotary switch, and the tangent of the loss angle in the range of 0.0001-10 is realized. The application can realize the output of the tangent of the capacitance loss angle in the range of 0.0001-10, and improve the long-term stability of the standard device.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of standard meter for measurement, and particularly relates to a standard meter for measurement of capacitance loss tangent in the range of 0.0001-10. BACKGROUND

[0002] The commonly used capacitance loss box uses a mechanical rotary switch direct connection structure, and realizes the output of the capacitance loss tangent value 0.0001-1 by selecting different capacitance values and resistance values of resistors for combination and series connection through the cooperation of multiple groups of switches. The existing capacitance loss box belongs to a passive circuit design, and has a complex circuit, a cumbersome structure, a large size and is inconvenient to carry and use. Meanwhile, the existing capacitance loss box relies on a mechanical motion structure, and the structure stability is inevitably deteriorated after long-term use and frequent transportation. Oxidation occurs in the rotary switch, the contact resistance is increased, and the loss value is out of tolerance, so that the overall use reliability is low.

[0003] In addition, the extension of the measurement range of the LCR tester increases the upper limit of the quantity value traceability and transmission of the capacitance loss factor from 1 to 10. However, the existing capacitance loss box adopts a traditional circuit design of mixed assembly of multiple wire bundles. With the increase of the output loss value, the influence of the lead layout and the distribution parameters of the mechanical rotary switch is increasingly prominent, which causes that the capacitance loss box cannot realize accurate reproduction under multiple frequencies in the range of 1-10, and the output value is significantly deviated from the theoretical calculation value. At present, a large number of compensation resistors are relied on for correction, which causes that the manufacturing and debugging process is complicated and has high complexity. Therefore, the existing capacitance loss box has been difficult to meet the actual application requirements, and urgently needs to be updated and replaced. SUMMARY

[0004] The purpose of the present application is to provide a standard meter for measurement of capacitance loss tangent in the range of 0.0001-10, which can realize the output of the capacitance loss tangent value 0.0001-10, and not only can expand the output range, but also can greatly improve the long-term stability of the standard meter.

[0005] In order to achieve the above purpose, one aspect of the present application provides a standard meter for measurement of capacitance loss tangent in the range of 0.0001-10, which comprises a first rotary switch, a second rotary switch, a capacitor array, a resistor array, a capacitance relay array, a resistance relay array, a power supply, a high-level measurement port and a low-level measurement port, a measurement loop is formed between the high-level measurement port and the low-level measurement port, and the power supply is connected with the first rotary switch and the second rotary switch.

[0006] The capacitor array comprises first to third capacitors, the resistor array comprises first to tenth resistors, the capacitor relay array comprises first to third relays connected in series, the first to third relays are connected with the first rotary switch and the first to third capacitors respectively, the first relay is connected with the high-level measurement port, the third relay is connected with the first resistor, and the first to third relays are powered by the power supply through the first rotary switch, so that one of the first to third capacitors can be connected to the measurement loop;

[0007] The resistor relay array comprises fourth to thirteenth relays connected in series, the fourth to thirteenth relays are connected with the second rotary switch and the low-level measurement port and connected with the first to tenth resistors respectively, the fourth to thirteenth relays are powered by the power supply through the second rotary switch, so that one or more of the first to tenth resistors can be connected to the measurement loop;

[0008] The capacitors and resistors connected to the measurement loop are controlled by the first rotary switch and the second rotary switch, so that the capacitance loss tangent value in the range of 0.0001-10 can be realized.

[0009] According to the above aspect of the present application, the 0.0001-10 range capacitance loss tangent measurement standard device can realize the output of the capacitance loss tangent value in the range of 0.0001-10, which not only expands the output range, but also greatly improves the long-term stability of the standard device. BRIEF DESCRIPTION OF DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor:

[0011] Figure 1 is a structure diagram of the 0.0001-10 range capacitance loss tangent measurement standard device of one embodiment of the present application;

[0012] Figure 2 is a circuit principle diagram of the 0.0001-10 range capacitance loss tangent measurement standard device of one embodiment of the present application. DETAILED DESCRIPTION

[0013] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0014] One embodiment of the present invention provides a standard for measuring the capacitance loss tangent in the range of 0.0001 to 10, such as... Figure 1 As shown, the standard device in this embodiment of the invention includes a first rotary switch, a second rotary switch, a capacitor array, a resistor array, a capacitor relay array, a resistor relay array, a power supply, a high-level measurement port Hi, and a low-level measurement port Lo. A measurement loop is formed between the high-level measurement port Hi and the low-level measurement port Lo, and the power supply is connected to the first rotary switch and the second rotary switch.

[0015] like Figure 2 As shown, the capacitor array includes first to third capacitors C1, C2, and C3; the resistor array includes first to tenth resistors R1 to R10; and the capacitor relay array includes first to third relays K1, K2, and K3 connected in series. All three relays are connected to a first rotary switch and to the first to third capacitors respectively. The first relay is connected to a high-level measurement port, and the third relay is connected to the first resistor. The first rotary switch controls the power supply S1 to energize the first to third relays, allowing one of the first to third capacitors to be connected to the measurement circuit.

[0016] The resistor relay array includes the fourth to thirteenth relays K4 to K13 connected in series. The fourth to thirteenth relays are all connected to the second rotary switch and the low-level measurement port, and are respectively connected to the first to tenth resistors. The power supply S1 is controlled by the second rotary switch to energize the fourth to thirteenth relays, which can connect one or more of the first to tenth resistors to the measurement circuit.

[0017] The capacitor and resistor in the measurement circuit are controlled by the first and second rotary switches, and the range of the loss tangent of the capacitor is 0.0001-10. Specifically, the first-third capacitors C1, C2, C3 are connected to the measurement circuit by switching the first rotary switch D1 to select one of the first-third relays K1, K2, K3 to be connected to the power supply S1; one or more of the first-tenth resistors R1-R10 are connected to the measurement circuit by switching the second rotary switch D2 to select one of the fourth-thirteenth relays K4-K10 to be connected to the power supply S1 and to switch the connection point of the resistor array, so that a series circuit of the capacitor and resistor is formed between the high-level measurement port Hi and the low-level measurement port Lo, and the equivalent loss tangent of the circuit can be calculated according to the formula D=2πFRC, where D represents the loss tangent, F represents the measurement frequency, R represents the resistance value, and C represents the capacitance value. The capacitance value ranges from 1nF to 10μF, and the optional values of the capacitor are 1nF, 10nF, 100nF, 1μF, and 10μF. The resistor is a high-precision metal film resistor, and the resistance value ranges from 0.159Ω to 0.160Ω, 1.59Ω to 1.60Ω, 15.9Ω to 16.0Ω, 159Ω to 160Ω, or 1590Ω to 1600Ω, which can be converted to a loss tangent value of 0.0001-10.

[0018] The connection relationship of the capacitor relay array, the resistor relay array, the capacitor array, and the resistor array is described in detail below with reference to the circuit schematic diagram of Figure 2 .

[0019] The first end of the first relay K1 is connected to the third end of the first rotary switch D1, the third end of the first relay K1 is connected to GND, the fourth end of the first relay K1 is connected to the high-level measurement port Hi, the fifth end of the first relay K1 is connected to the fourth end of the second relay K2, the sixth end of the first relay K1 is connected to GND, and the eighth end of the first relay K1 is connected to the fourth end of the first rotary switch D1; the first end of the second relay K2 is connected to the fifth end of the first rotary switch D1, the third end of the second relay K2 is connected to GND, the fifth end of the second relay K2 is connected to the fourth end of the third relay K3, the sixth end of the second relay K2 is connected to GND, and the eighth end of the second relay K2 is connected to the sixth end of the first rotary switch D1; the first end of the third relay K3 is connected to the seventh end of the first rotary switch D1, the third end of the third relay K3 is connected to GND, the fifth end of the third relay K3 is connected to the first end of the first resistor, the sixth end of the third relay K3 is connected to GND, and the eighth end of the third relay K3 is connected to the eighth end of the first rotary switch D1.

[0020] The first end of the fourth relay K4 is connected with the third end of the second rotary switch D2, the second, third and fourth ends of the fourth relay K4 are connected with GND, the fifth end of the fourth relay K4 is connected with the second end of the first resistor R1, the seventh end of the fourth relay K4 is connected with the low level measurement port Lo, the eighth end of the fourth relay K4 is connected with the fourth end of the second rotary switch D2; the first end of the fifth relay K5 is connected with the fifth end of the second rotary switch D2, the second, third and fourth ends of the fifth relay K5 are connected with GND, the fifth end of the fifth relay K5 is connected with the second end of the second resistor R2, the seventh end of the fifth relay K5 is connected with the low level measurement port Lo, the eighth end of the fifth relay K5 is connected with the sixth end of the second rotary switch D2; the first end of the sixth relay K6 is connected with the seventh end of the second rotary switch D2, the second, third and fourth ends of the sixth relay K6 are connected with GND, the fifth end of the sixth relay K6 is connected with the second end of the third resistor R3, the seventh end of the sixth relay K6 is connected with the low level measurement port Lo, the eighth end of the sixth relay K6 is connected with the eighth end of the second rotary switch D2; the first end of the seventh relay K7 is connected with the ninth end of the second rotary switch D2, the second, third and fourth ends of the seventh relay K7 are connected with GND, the fifth end of the seventh relay K7 is connected with the second end of the fourth resistor R4, the seventh end of the seventh relay K7 is connected with the low level measurement port Lo, the eighth end of the seventh relay K7 is connected with the tenth end of the second rotary switch D2; the first end of the eighth relay K8 is connected with the eleventh end of the second rotary switch D2, the second, third and fourth ends of the eighth relay K8 are connected with GND, the fifth end of the eighth relay K8 is connected with the second end of the fifth resistor R5, the seventh end of the eighth relay K8 is connected with the low level measurement port Lo, the eighth end of the eighth relay K8 is connected with the twelfth end of the second rotary switch D2; the first end of the ninth relay K9 is connected with the thirteenth end of the second rotary switch D2, the second, third and fourth ends of the ninth relay K9 are connected with GND, the fifth end of the ninth relay K9 is connected with the second end of the sixth resistor R6, the seventh end of the ninth relay K9 is connected with the low level measurement port Lo, the eighth end of the ninth relay K9 is connected with the fourteenth end of the second rotary switch D2; the first end of the tenth relay K10 is connected with the fifteenth end of the second rotary switch D2, the second, third and fourth ends of the tenth relay K10 are connected with GND, the fifth end of the tenth relay K10 is connected with the second end of the seventh resistor R7, the seventh end of the tenth relay K10 is connected with the low level measurement port Lo, the eighth end of the tenth relay K10 is connected with the sixteenth end of the second rotary switch D2;The first end of the eleventh relay K11 is connected with the seventeenth end of the second rotary switch D2, the second, third and fourth ends of the eleventh relay K11 are connected with GND, the fifth end of the eleventh relay K11 is connected with the second end of the eighth resistor R8, the seventh end of the eleventh relay K11 is connected with the low level measurement port Lo, the eighth end of the eleventh relay K11 is connected with the eighteenth end of the second rotary switch D2; the first end of the twelfth relay K12 is connected with the nineteenth end of the second rotary switch D2, the second, third and fourth ends of the twelfth relay K12 are connected with GND, the fifth end of the twelfth relay K12 is connected with the second end of the ninth resistor R9, the seventh end of the twelfth relay K12 is connected with the low level measurement port Lo, the eighth end of the twelfth relay K12 is connected with the twentieth end of the second rotary switch D2; the first end of the thirteenth relay K13 is connected with the twenty first end of the second rotary switch D2, the second, third and fourth ends of the thirteenth relay K13 are connected with GND, the fifth end of the thirteenth relay K13 is connected with the second end of the tenth resistor R10, the seventh end of the thirteenth relay K13 is connected with the low level measurement port Lo, the eighth end of the thirteenth relay K13 is connected with the twenty second end of the second rotary switch D2.

[0021] Capacitor array: the first end of the first capacitor C1 is connected with the second end of the first relay K1, the second end of the first capacitor C1 is connected with the seventh end of the first relay K1; the first end of the second capacitor C2 is connected with the second end of the second relay K2, the second end of the second capacitor C2 is connected with the seventh end of the second relay K2; the first end of the third capacitor C3 is connected with the second end of the third relay K3, the second end of the third capacitor C3 is connected with the seventh end of the third relay K3.

[0022] Resistor array: the first end of the first resistor R1 is connected with the fifth end of the third relay K3, the second end of the first resistor R1 is connected with the first end of the second resistor R2, the second end of the second resistor R2 is connected with the first end of the third resistor R3, the second end of the third resistor R3 is connected with the first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected with the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected with the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected with the first end of the seventh resistor R7, the second end of the seventh resistor R7 is connected with the first end of the eighth resistor R8, the second end of the eighth resistor R8 is connected with the first end of the ninth resistor R9, the second end of the ninth resistor R9 is connected with the first end of the tenth resistor R10, the second end of the tenth resistor R10 is connected with the fifth end of the thirteenth relay R13.

[0023] The positive terminal of the power supply is connected with the ninth terminal of the first rotary switch D1 and the twenty-third terminal of the second rotary switch D2; the negative terminal of the power supply is connected with the tenth terminal of the rotary switch D1 and the twenty-fourth terminal of the rotary switch D2.

[0024] In summary, the capacitor loss tangent measuring standard device with the range of 0.0001-10 of the embodiment of the application realizes the output of the capacitor loss tangent value of 0.0001-10 by controlling the value combination of the capacitor and the resistor in the circuit through the switching action of the relay. The rotary switch is only used for controlling the power supply of the relay, and the aging and performance of the rotary switch are not directly related, and no additional distributed parameters are introduced. At the same time, the distributed parameters are significantly reduced through the high-frequency optimization of the device layout and grounding design. This design not only expands the output range, but also greatly improves the long-term stability of the device.

[0025] The above only describes certain exemplary embodiments of the application by way of illustration, and it is needless to say that the described embodiments can be modified in various ways without departing from the spirit and scope of the application for those skilled in the art. Therefore, the above drawings and descriptions are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the application.

Claims

1. A standard for measuring a loss tangent of a capacitance in a range of 0.0001 to 10, characterized by, It includes first and second rotary switches, capacitor array, resistor array, capacitor relay array, resistor relay array, power supply, high-level measurement port and low-level measurement port, a measurement loop is formed between the high-level measurement port and the low-level measurement port, and the power supply is connected to the first rotary switch and the second rotary switch; The capacitor array includes a first to a third capacitor, the resistor array includes a first to a tenth resistor connected in series, and the capacitor relay array includes a first to a third relay connected in series. The first to third relays are all connected to a first rotary switch and are respectively connected to the first to the third capacitor. The first relay is connected to a high-level measurement port, and the third relay is connected to the first resistor. The power supply is controlled by the first rotary switch to energize the first to the third relays, so that one of the first to the third capacitors can be connected to the measurement circuit. The resistor relay array includes a fourth to a thirteenth relay connected in series. The fourth to thirteenth relays are all connected to a second rotary switch and are respectively connected between the first to tenth resistors and the low-level measurement port. The power supply is controlled by the second rotary switch to energize the fourth to thirteenth relays, so that one or more of the first to tenth resistors can be connected to the measurement circuit. By controlling the capacitors and resistors connected to the measurement circuit through the first and second rotary switches, a capacitance loss tangent value in the range of 0.0001 to 10 can be achieved. The first and second rotary switches are only used to control the power supply of the corresponding relays and do not introduce additional distributed parameters. The first to thirteenth relays are all grounded. Through device layout and grounding design, the distributed parameters are reduced.

2. The standard of claim 1, wherein The first terminal of the first relay is connected to the third terminal of the first rotary switch, the third terminal of the first relay is grounded, the fourth terminal of the first relay is connected to the high-level measurement port, the fifth terminal of the first relay is connected to the fourth terminal of the second relay, the sixth terminal of the first relay is grounded, and the eighth terminal of the first relay is connected to the fourth terminal of the first rotary switch. The first terminal of the second relay is connected to the fifth terminal of the first rotary switch, the third terminal of the second relay is grounded, the fifth terminal of the second relay is connected to the fourth terminal of the third relay, the sixth terminal of the second relay is grounded, and the eighth terminal of the second relay is connected to the sixth terminal of the first rotary switch. The first terminal of the third relay is connected to the seventh terminal of the first rotary switch, the third terminal of the third relay is grounded, the fifth terminal of the third relay is connected to the first terminal of the first resistor, the sixth terminal of the third relay is grounded, and the eighth terminal of the third relay is connected to the eighth terminal of the first rotary switch. The first terminal of the first capacitor is connected to the second terminal of the first relay, and the second terminal of the first capacitor is connected to the seventh terminal of the first relay; the first terminal of the second capacitor is connected to the second terminal of the second relay, and the second terminal of the second capacitor is connected to the seventh terminal of the second relay; the first terminal of the third capacitor is connected to the second terminal of the third relay, and the second terminal of the third capacitor is connected to the seventh terminal of the third relay.

3. The standard of claim 2, wherein The first end of the fourth relay is connected with the third end of the second rotary switch, the second, third and fourth ends of the fourth relay are grounded, the fifth end of the fourth relay is connected with the second end of the first resistor, the seventh end of the fourth relay is connected with the low level measurement port, and the eighth end of the fourth relay is connected with the fourth end of the second rotary switch; The first end of the fifth relay is connected with the fifth end of the second rotary switch, the second, third and fourth ends of the fifth relay are grounded, the fifth end of the fifth relay is connected with the second end of the second resistor, the seventh end of the fifth relay is connected with the low level measurement port, and the eighth end of the fifth relay is connected with the sixth end of the second rotary switch; The first end of the sixth relay is connected with the seventh end of the second rotary switch, the second, third and fourth ends of the sixth relay are grounded, the fifth end of the sixth relay is connected with the second end of the third resistor, the seventh end of the sixth relay is connected with the low level measurement port, and the eighth end of the sixth relay is connected with the eighth end of the second rotary switch; The first end of the seventh relay is connected with the ninth end of the second rotary switch, the second, third and fourth ends of the seventh relay are grounded, the fifth end of the seventh relay is connected with the second end of the fourth resistor, the seventh end of the seventh relay is connected with the low level measurement port, and the eighth end of the seventh relay is connected with the tenth end of the second rotary switch; The first end of the eighth relay is connected with the eleventh end of the second rotary switch, the second, third and fourth ends of the eighth relay are grounded, the fifth end of the eighth relay is connected with the second end of the fifth resistor, the seventh end of the eighth relay is connected with the low level measurement port, and the eighth end of the eighth relay is connected with the twelfth end of the second rotary switch; The first end of the ninth relay is connected with the thirteenth end of the second rotary switch, the second, third and fourth ends of the ninth relay are grounded, the fifth end of the ninth relay is connected with the second end of the sixth resistor, the seventh end of the ninth relay is connected with the low level measurement port, and the eighth end of the ninth relay is connected with the fourteenth end of the second rotary switch; The first end of the tenth relay is connected with the fifteenth end of the second rotary switch, the second, third and fourth ends of the tenth relay are grounded, the fifth end of the tenth relay is connected with the second end of the seventh resistor, the seventh end of the tenth relay is connected with the low level measurement port, and the eighth end of the tenth relay is connected with the sixteenth end of the second rotary switch; The first end of the eleventh relay is connected with the seventeenth end of the second rotary switch, the second, third and fourth ends of the eleventh relay are grounded, the fifth end of the eleventh relay is connected with the second end of the eighth resistor, the seventh end of the eleventh relay is connected with the low level measurement port, and the eighth end of the eleventh relay is connected with the eighteenth end of the second rotary switch; The first end of the twelfth relay is connected with the nineteenth end of the second rotary switch, the second, third and fourth ends of the twelfth relay are grounded, the fifth end of the twelfth relay is connected with the second end of the ninth resistor, the seventh end of the twelfth relay is connected with the low level measurement port, and the eighth end of the twelfth relay is connected with the twentieth end of the second rotary switch; The first end of the thirteenth relay is connected with the twenty-first end of the second rotary switch, the second, third and fourth ends of the thirteenth relay are grounded, the fifth end of the thirteenth relay is connected with the second end of the tenth resistor, the seventh end of the thirteenth relay is connected with the low level measurement port, and the eighth end of the thirteenth relay is connected with the twenty-second end of the second rotary switch; The first end of the first resistor is connected with the fifth end of the third relay, the second end of the first resistor is connected with the first end of the second resistor, the second end of the second resistor is connected with the first end of the third resistor, the second end of the third resistor is connected with the first end of the fourth resistor, the second end of the fourth resistor is connected with the first end of the fifth resistor, the second end of the fifth resistor is connected with the first end of the sixth resistor, the second end of the sixth resistor is connected with the first end of the seventh resistor, the second end of the seventh resistor is connected with the first end of the eighth resistor, the second end of the eighth resistor is connected with the first end of the ninth resistor, the second end of the ninth resistor is connected with the first end of the tenth resistor, and the second end of the tenth resistor is connected with the fifth end of the thirteenth relay.

4. The standard of claim 3, wherein The positive end of the power supply is connected with the ninth end of the first rotary switch and the twenty-third end of the second rotary switch, and the negative end of the power supply is connected with the tenth end of the first rotary switch and the twenty-fourth end of the second rotary switch.

5. A standard according to any one of claims 1 to 4, wherein The capacitance value of the first to third capacitors ranges from 1nF to 10uF, the first to tenth resistors are high-precision metal film resistors, and the resistance value ranges from 0.159 to 0.160Ω, 1.59 to 1.60Ω, 15.9 to 16.0Ω, 159 to 160Ω or 1590 to 1600Ω.

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