Self-constructing loop-based conductive slip ring contact resistance detection device and detection method

Abstract

The application provides a self-loop-based conductive slip ring contact resistance detection device and method. The detection device comprises a relay array unit, the relay array unit comprises n relay groups, any relay group comprises a first relay and a second relay; a relay array control unit is used for controlling the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on to connect the i-th slip ring channel and the j-th slip ring channel in series into a resistance sampling loop; a signal conditioning unit is connected with the resistance sampling unit and is used for obtaining a conditioned voltage signal according to the voltage output of the resistance sampling unit; a processing unit is connected with the signal conditioning unit and is used for controlling the relay array control unit according to the conditioned voltage signal. The technical scheme of the application can solve the technical problems of large size and high detection cost of the conductive slip ring contact resistance detection device in the prior art.

Description

Technical Field

[0001] This invention relates to the field of resistance detection technology, and in particular to a conductive slip ring contact resistance detection device and method based on a self-constructed circuit. Background Technology

[0002] The main function of a conductive slip ring is to solve the problem of wire entanglement during 360° rotation of equipment. In electrical design, wires need to be connected to rotating parts. When mechanical parts rotate continuously and without restriction at 360°, wire entanglement can occur. To ensure accurate transmission of current or signals to the rotating parts, an electrical rotary connector is needed to complete the rotational connection for transmitting power and signals. The presence of a conductive slip ring greatly simplifies the system structure and prevents wires from twisting during rotation.

[0003] Conductive slip rings can experience various issues, including long-term wear leading to dust accumulation and poor contact or increased contact resistance; brush deformation due to prolonged stress can cause slippage; brush holder deformation can result in no contact with the conductive ring; and contact oxidation or dust accumulation can occur due to prolonged exposure to harsh environments. These changes directly affect the performance of the slip ring turntable, and in some cases, even directly impact electrical results, necessitating re-testing of the conductive slip rings.

[0004] The common method for testing the contact resistance of conductive slip rings is to connect a low-resistance tester to the two measuring terminals of the slip ring to measure the resistance. Conductive slip rings are generally multi-channel, and if multiple channels need to be measured simultaneously, multiple low-resistance testers are required, which increases the testing cost and the size of the testing device. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] According to one aspect of the present invention, a conductive slip ring contact resistance detection device based on a self-constructed circuit is provided. The device comprises: a relay array unit, a resistance sampling unit, a signal conditioning unit, a processing unit, and a relay array control unit. The relay array unit includes n relay groups, each corresponding to one of the n slip ring channels of the conductive slip ring. Each relay group includes a first relay and a second relay. Each first relay is connected to the power supply of the corresponding slip ring channel and the resistance sampling unit, and each second relay is connected to the first terminal of the sampling resistor in the corresponding slip ring channel and the resistance sampling unit. The relay array control unit is connected to each first relay. The relay array control unit is connected to any second relay. It controls the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on, while the remaining relays are turned off, so that the i-th slip ring channel and the j-th slip ring channel are connected in series to the resistance sampling circuit, where i = [1,2,……,n], j = [1,2,……,n], j ≠ i, and n is an integer. The signal conditioning unit is connected to the resistance sampling unit. The signal conditioning unit is used to obtain the conditioned voltage signal based on the voltage output of the resistance sampling unit. The conditioned voltage signal is used to calculate the contact resistance of the conductive slip ring. The processing unit is connected to the signal conditioning unit. The processing unit is used to control the relay array control unit based on the conditioned voltage signal.

[0007] Furthermore, the signal conditioning unit includes a first operational amplifier, a second operational amplifier, a first differential input circuit, and a second differential input circuit. The non-inverting input terminal of the first operational amplifier is connected to the first terminal of the resistor sampling unit, the output terminal of the first operational amplifier is connected to the second differential input circuit, the non-inverting input terminal of the second operational amplifier is connected to the power supply of the resistor sampling unit, and the output terminal of the second operational amplifier is connected to the first differential input circuit. The inverting input terminals of both the first and second operational amplifiers are grounded. The first differential input circuit and the second differential input circuit are used to output the conditioned voltage signal, respectively.

[0008] Furthermore, the first differential input circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, and a third operational amplifier. The first resistor is connected to the output terminal of the second operational amplifier and the inverting input terminal of the third operational amplifier, respectively. The second resistor is connected to the inverting input terminal and the output terminal of the third operational amplifier, respectively. The third resistor is connected to the reference voltage and the non-inverting input terminal of the third operational amplifier, respectively. The fourth resistor is connected to the non-inverting input terminal of the third operational amplifier and ground, respectively. The output terminal of the third operational amplifier outputs the first conditioned voltage signal.

[0009] Furthermore, the second differential input circuit includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a fourth operational amplifier. The fifth resistor is connected to the output terminal of the first operational amplifier and the inverting input terminal of the fourth operational amplifier, respectively. The sixth resistor is connected to the inverting input terminal and the output terminal of the fourth operational amplifier, respectively. The seventh resistor is connected to the reference voltage and the non-inverting input terminal of the fourth operational amplifier, respectively. The eighth resistor is connected to the non-inverting input terminal of the fourth operational amplifier and ground, respectively. The output terminal of the fourth operational amplifier outputs the second conditioned voltage signal.

[0010] Furthermore, the processing unit includes an ADC converter and a CPU processor. The ADC converter is connected to the signal conditioning unit and the CPU processor respectively, and is used to acquire digital signals based on the conditioned voltage signals. The CPU processor is connected to the relay array control unit, and is used to control the ADC converter and the relay array control unit based on the digital signals.

[0011] Furthermore, the conductive slip ring contact resistance detection device based on self-constructed circuit also includes a communication unit, which is connected to the DSP processor. The communication unit is used to receive external control commands and output digital signals processed by the DSP processor.

[0012] Furthermore, the communication unit can use an RS422 communication port.

[0013] According to another aspect of the present invention, a method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit is provided. This method uses the conductive slip ring contact resistance detection device based on a self-constructed circuit as described above to detect the contact resistance of the conductive slip ring.

[0014] Furthermore, the gain of both the first operational amplifier and the second operational amplifier is 1.

[0015] Furthermore, the conductive slip ring contact resistance detection method based on a self-constructed circuit includes: the processing unit controls the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on through the relay array control unit, while the remaining relays are turned off; where i = [1,2,……,n], j = [1,2,……,n], j ≠ i, and n is an integer; according to Obtain the total contact resistance of the i-th slip ring channel and the j-th slip ring channel; where R ij R is the total contact resistance of the i-th slip ring channel and the j-th slip ring channel. ij =R i +R j R i Let R be the contact resistance of the i-th slip ring channel to be determined. j R is the contact resistance of the j-th slip ring channel to be determined;c V is the resistance value of the sampling resistor. j V is the output voltage of the resistor sampling unit at the power supply terminal. c V is the output voltage of the resistance sampling unit at the first terminal of the sampling resistor; adj The voltage after the first conditioning step, V adc This is the voltage after the second conditioning; V ref G3 is the reference voltage; G3 is the gain of the third operational amplifier. R1, R2, R3, and R4 represent the resistance values ​​of the first, second, third, and fourth resistors, respectively; G4 represents the gain of the fourth operational amplifier. R5, R6, R7, and R8 are the resistance values ​​of the fifth, sixth, seventh, and eighth resistors, respectively. The processing unit controls the relay array control unit to obtain the total value of i×j contact resistances, and obtains the contact resistance of any slip ring channel based on the total value of i×j contact resistances to complete the detection of the contact resistance of the conductive slip ring.

[0016] This invention provides a conductive slip ring contact resistance detection device and method based on a self-constructed circuit. The device includes multiple first and second relays corresponding one-to-one with multiple conductive slip ring channels. A relay array control unit selects specific first and second relays to connect the corresponding slip ring channel to the resistance sampling circuit. The contact resistance of the conductive slip ring is then calculated based on the voltage signal obtained by the signal conditioning unit. This invention features a simple and rationally designed conductive slip ring contact resistance detection device that meets the measurement accuracy requirements of the circuit or slip ring channel, achieving low-resistance detection of the conductive slip ring. It also enables the detection of both static and dynamic contact resistance. Compared with existing technologies, this invention solves the problems of large size and high cost in existing conductive slip ring contact resistance detection devices. Attached Figure Description

[0017] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0018] Figure 1 A schematic diagram of the structure of a conductive slip ring contact resistance detection device based on a self-constructed circuit according to a specific embodiment of the present invention is shown.

[0019] Figure 2A schematic diagram of the contact resistance detection principle of a conductive slip ring based on a self-constructed circuit, according to a specific embodiment of the present invention, is shown. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0022] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0023] like Figure 1 and Figure 2As shown in the figure, a conductive slip ring contact resistance detection device based on a self-constructed circuit is provided according to a specific embodiment of the present invention. The conductive slip ring contact resistance detection device based on a self-constructed circuit includes: a relay array unit, a resistance sampling unit, a signal conditioning unit, a processing unit, and a relay array control unit. The relay array unit includes n relay groups, each of which corresponds one-to-one with one of the n slip ring channels of the conductive slip ring. Each relay group includes a first relay and a second relay. Each first relay is connected to the power supply of the corresponding slip ring channel and the resistance sampling unit, and each second relay is connected to the first terminal of the sampling resistor in the corresponding slip ring channel and the resistance sampling unit, respectively. The relay array control unit is connected to each first relay... An electrical appliance is connected to any second relay. The relay array control unit controls the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on, while the remaining relays are turned off, so that the i-th slip ring channel and the j-th slip ring channel are connected in series to the resistance sampling circuit, where i = [1,2,……,n], j = [1,2,……,n], j ≠ i, and n is an integer. The signal conditioning unit is connected to the resistance sampling unit. The signal conditioning unit is used to obtain the conditioned voltage signal based on the voltage output of the resistance sampling unit. The conditioned voltage signal is used to calculate the contact resistance of the conductive slip ring. The processing unit is connected to the signal conditioning unit. The processing unit is used to control the relay array control unit based on the conditioned voltage signal.

[0024] This configuration provides a conductive slip ring contact resistance detection device based on a self-constructed circuit. This device includes multiple first and second relays, each corresponding to a different conductive slip ring channel. A relay array control unit selects specific first and second relays to connect the corresponding slip ring channel to the resistance sampling circuit. The contact resistance of the conductive slip ring is then calculated based on the voltage signal obtained by the signal conditioning unit. This invention provides a simple and rationally designed conductive slip ring contact resistance detection device that meets the measurement accuracy requirements of the circuit or slip ring channel, achieving low-resistance detection of the conductive slip ring. It also enables the detection of both static and dynamic contact resistance. Compared with existing technologies, this invention solves the problems of large size and high cost in existing conductive slip ring contact resistance detection devices.

[0025] Furthermore, in this invention, the signal conditioning unit includes a first operational amplifier, a second operational amplifier, a first differential input circuit, and a second differential input circuit. The non-inverting input terminal of the first operational amplifier is connected to the first terminal of the resistor sampling unit, the output terminal of the first operational amplifier is connected to the second differential input circuit, the non-inverting input terminal of the second operational amplifier is connected to the power supply of the resistor sampling unit, and the output terminal of the second operational amplifier is connected to the first differential input circuit. The inverting input terminals of both the first and second operational amplifiers are grounded. The first differential input circuit and the second differential input circuit are respectively used to output the conditioned voltage signal.

[0026] In a specific embodiment of the present invention, to achieve voltage signal conditioning by the differential input circuit, a first differential input circuit can be configured including a first resistor, a second resistor, a third resistor, a fourth resistor, and a third operational amplifier. The first resistor is connected to the output terminal of the second operational amplifier and the inverting input terminal of the third operational amplifier, the second resistor is connected to the inverting input terminal and the output terminal of the third operational amplifier, the third resistor is connected to a reference voltage and the non-inverting input terminal of the third operational amplifier, and the fourth resistor is connected to the non-inverting input terminal of the third operational amplifier and ground. The output terminal of the third operational amplifier outputs a first conditioned voltage signal. Similarly, a second differential input circuit can be configured including a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a fourth operational amplifier. The fifth resistor is connected to the output terminal of the first operational amplifier and the inverting input terminal of the fourth operational amplifier, the sixth resistor is connected to the inverting input terminal and the output terminal of the fourth operational amplifier, the seventh resistor is connected to a reference voltage and the non-inverting input terminal of the fourth operational amplifier, and the eighth resistor is connected to the non-inverting input terminal of the fourth operational amplifier and ground. The output terminal of the fourth operational amplifier outputs a second conditioned voltage signal.

[0027] In this embodiment, to simplify the detection calculation process, the first and second operational amplifiers can be configured as instrumentation amplifiers with a gain of 1; the third and fourth operational amplifiers are high-precision operational amplifiers. The reference voltage is provided by a reference power supply. The first and third resistors have equal resistance values, the second and fourth resistors have equal resistance values, the fifth and seventh resistors have equal resistance values, and the sixth and eighth resistors have equal resistance values. The contact resistance of each relay contact is less than 40mΩ.

[0028] In this configuration, after the relay array control unit turns on the first relay of the i-th relay group and the second relay of the j-th relay group, the i-th slip ring channel is used as a common channel. The i-th and j-th slip ring channels are connected in series in the resistance sampling circuit, forming a contact resistance detection circuit with the sampling resistor and the signal conditioning unit. This contact resistance detection circuit satisfies... Among them, Vadj G1 represents the voltage after the first conditioning step, and G3 represents the gain of the third operational amplifier. R1, R2, R3, and R4 are the resistance values ​​of the first, second, third, and fourth resistors, respectively; V ref Reference voltage; V is the output voltage of the second operational amplifier, and G2 is the gain of the second operational amplifier; j V is the output voltage of the resistor sampling unit at the power supply terminal. adc G1 represents the voltage after the second conditioning step, and G4 represents the gain of the fourth operational amplifier. R5, R6, R7, and R8 are the resistance values ​​of the fifth, sixth, seventh, and eighth resistors, respectively. V is the output voltage of the first operational amplifier, and G1 is the gain of the first operational amplifier; c R is the output voltage of the resistance sampling unit at the first terminal of the sampling resistor; c R is the resistance value of the sampling resistor. ij R is the total contact resistance of the i-th slip ring channel and the j-th slip ring channel. ij =R i +R j R i Let R be the contact resistance of the i-th slip ring channel to be determined. j Let be the contact resistance of the j-th slip ring channel to be determined.

[0029] In an embodiment of the present invention, G1 = 1, G2 = 1, from which it can be deduced that the total contact resistance of the i-th slip ring channel and the j-th slip ring channel can be determined according to... Obtain.

[0030] By selectively activating multiple first relays and multiple second relays through the relay array control unit, the total value of i×j contact resistances can be obtained. Based on the total value of i×j contact resistances, the contact resistance of any slip ring channel can be obtained.

[0031] In this invention, the number of relay groups in the relay array unit can be specifically set according to the number of slip ring channels of the conductive slip ring. As a specific embodiment of this invention, the relay array unit includes 8 relay groups, with each of the 8 relay groups corresponding one-to-one with one of the 8 slip ring channels of the conductive slip ring. Using the above-described conductive slip ring contact resistance detection device based on a self-constructed circuit, the total contact resistance value R of 56 contacts can be obtained sequentially. 12 R 13 R 14 …R 23 …By selecting the sum of three relevant contact resistance values, the corresponding slip ring channel contact resistance can be obtained. For example, based on… The contact resistances R1, R2, and R3 of the 1st, 2nd, and 3rd slip ring channels can then be obtained. This process can be repeated to obtain the contact resistances of each of the eight slip ring channels.

[0032] Furthermore, in this invention, in order to enable the processing unit to control the relay array control unit, the processing unit can be configured to include an ADC converter and a CPU processor. The ADC converter is connected to the signal conditioning unit and the CPU processor respectively, and the ADC converter is used to acquire digital signals based on the conditioned voltage signals. The CPU processor is connected to the relay array control unit, and the CPU processor is used to control the ADC converter and the relay array control unit based on the digital signals.

[0033] In a specific embodiment of the present invention, the ADC converter performs the conversion from analog to digital signals, which can be accomplished by a high-speed ADC chip. The CPU processor can be a DSP processor. The DSP processor controls the A / D conversion timing, and the digital result converted by the ADC converter is transmitted to the DSP processor for processing through the DSP processor's external storage interface.

[0034] Furthermore, in this invention, the conductive slip ring contact resistance detection device based on a self-constructed circuit also includes a communication unit. The communication unit is connected to a DSP processor and is used to receive external control commands and output digital signals processed by the DSP processor. In this invention, the DSP processor receives control commands from the communication port through the communication unit, and then controls the on / off state of the corresponding relays through the relay array control unit; after receiving and processing the digital signals from the ADC converter, the DSP processor outputs them to the outside world through the communication unit.

[0035] In a specific embodiment of the present invention, the communication unit may use an RS422 communication port. The control commands received by the DSP processor may adopt a frame protocol format. After receiving the control commands sent from the outside via the asynchronous RS422 communication interface, the DSP processor software processes and analyzes them to determine whether the control command is a correct frame. If it is, the DSP provides control signals through the input / output GPIO ports. After analyzing the control commands, the DSP processor software provides response information and sends the response information to the outside via the asynchronous RS422 communication interface, realizing the handshake of data communication and ensuring the reliability of communication.

[0036] The conductive slip ring contact resistance detection device based on a self-constructed circuit of the present invention utilizes the principle of Ohm's law. By designing a reasonable sampling circuit and equipping it with a detection element of reasonable precision, it meets the measurement accuracy requirements of the circuit or slip ring channel, realizes low resistance detection of conductive slip rings, and can also detect the static and dynamic contact resistance of conductive slip rings, thereby expanding the conductive slip ring detection technology.

[0037] According to another aspect of the present invention, a method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit is provided. This method uses the conductive slip ring contact resistance detection device based on a self-constructed circuit as described above to detect the contact resistance of the conductive slip ring.

[0038] Further, in this invention, the conductive slip ring contact resistance detection method based on a self-constructed circuit includes: a processing unit controls the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on through a relay array control unit, while the remaining relays are turned off; where i = [1,2,……,n], j = [1,2,……,n], j ≠ i, and n is an integer; according to The processing unit obtains the total contact resistance of the i-th and j-th slip ring channels; the processing unit controls the relay array control unit to obtain the total contact resistance of i×j channels, and obtains the contact resistance of any slip ring channel based on the total contact resistance of i×j channels to complete the detection of the contact resistance of the conductive slip ring.

[0039] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figure 1 and Figure 2 The conductive slip ring contact resistance detection device based on a self-constructed circuit of the present invention will be described in detail.

[0040] like Figure 1 and Figure 2 As shown, a specific embodiment of the present invention provides a conductive slip ring contact resistance detection device based on a self-constructed circuit. The conductive slip ring contact resistance detection device based on a self-constructed circuit includes a relay array unit, a resistance sampling unit, a signal conditioning unit, a processing unit, a relay array control unit, and a communication unit.

[0041] The relay array unit includes n relay groups k1, k2, ..., kn, each corresponding to one of the n slip ring channels of the conductive slip ring. Each relay group includes a first relay and a second relay. The first relays include k1a, k2a, ..., kna, and the second relays include k1b, k2b, ..., knb. Each first relay is connected to the power supply of the corresponding slip ring channel and the resistance sampling unit, and each second relay is connected to the sampling resistor R in the corresponding slip ring channel and the resistance sampling unit. c The first end is connected.

[0042] The relay array control unit is connected to any first relay and any second relay. The relay array control unit is used to control the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on, while the remaining relays are turned off, so as to connect the i-th slip ring channel and the j-th slip ring channel in series into the resistance sampling circuit, where i = [1,2,……,n], j = [1,2,……,n], j ≠ i, and n is an integer.

[0043] The signal conditioning unit is connected to the resistor sampling unit. The signal conditioning unit is used to obtain the conditioned voltage signal based on the voltage output of the resistor sampling unit. The conditioned voltage signal is used to calculate the contact resistance of the conductive slip ring.

[0044] The signal conditioning unit includes a first operational amplifier A1, a second operational amplifier A2, a first differential input circuit, and a second differential input circuit. The non-inverting input terminal of the first operational amplifier A1 is connected to the first terminal of the resistor sampling unit, and the output terminal of the first operational amplifier A1 is connected to the second differential input circuit. The non-inverting input terminal of the second operational amplifier A2 is connected to the power supply VCC1 of the resistor sampling unit, and the output terminal of the second operational amplifier A2 is connected to the first differential input circuit. The inverting input terminals of both the first operational amplifier A1 and the second operational amplifier A2 are grounded. The first differential input circuit and the second differential input circuit are used to output the conditioned voltage signal, respectively.

[0045] The first differential input circuit includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a third operational amplifier A3. The first resistor R1 is connected to the output terminal of the second operational amplifier A2 and the inverting input terminal of the third operational amplifier A3. The second resistor R2 is connected to both the inverting input terminal and the output terminal of the third operational amplifier A3. The third resistor R3 is connected to the reference voltage V. ref The fourth resistor R4 is connected to the positive input terminal of the third operational amplifier A3 and ground, respectively. The output terminal of the third operational amplifier A3 outputs the first conditioned voltage signal V. adj .

[0046] The second differential input circuit includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a fourth operational amplifier A4. The fifth resistor R5 is connected to the output terminal of the first operational amplifier A1 and the inverting input terminal of the fourth operational amplifier A4. The sixth resistor R6 is connected to both the inverting input terminal and the output terminal of the fourth operational amplifier A4. The seventh resistor R7 is connected to the reference voltage V. ref The fourth operational amplifier A4 is connected to its positive input terminal, and the eighth resistor R8 is connected to both the positive input terminal of the fourth operational amplifier A4 and ground. The output terminal of the fourth operational amplifier A4 outputs the second conditioned voltage signal V.adc .

[0047] The processing unit is connected to the signal conditioning unit and is used to control the relay array control unit based on the conditioned voltage signal. The processing unit includes an ADC converter and a CPU processor. The ADC converter is connected to both the signal conditioning unit and the CPU processor, and is used to acquire digital signals based on the conditioned voltage signal. The CPU processor is connected to the relay array control unit and is used to control both the ADC converter and the relay array control unit based on the digital signals.

[0048] The communication unit connects to the DSP processor and is used to receive external control commands and output digital signals processed by the DSP processor. The communication unit can use an RS422 communication port.

[0049] In summary, this invention provides a conductive slip ring contact resistance detection device and method based on a self-constructed circuit. This device includes multiple first and second relays, each corresponding to a different conductive slip ring channel. A relay array control unit selects specific first and second relays to connect the corresponding slip ring channel to the resistance sampling circuit. The contact resistance of the conductive slip ring is then calculated based on the voltage signal obtained by the signal conditioning unit. The conductive slip ring contact resistance detection device of this invention has a simple and reasonable structure, meets the measurement accuracy requirements of the circuit or slip ring channel, achieves low-resistance detection of the conductive slip ring, and can detect both static and dynamic contact resistance. Compared with existing technologies, this invention solves the problems of large size and high detection cost in existing conductive slip ring contact resistance detection devices.

[0050] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0051] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit, characterized in that, The method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit employs a conductive slip ring contact resistance detection device based on a self-constructed circuit to detect the contact resistance of the conductive slip ring. The conductive slip ring contact resistance detection device based on a self-constructed circuit includes: a relay array unit, a resistance sampling unit, a signal conditioning unit, a processing unit, and a relay array control unit. The relay array unit includes n relay groups, each corresponding to one of the n slip ring channels of the conductive slip ring. Each relay group includes a first relay and a second relay. Each first relay is connected to the power supply of the corresponding slip ring channel and the resistance sampling unit, and each second relay is connected to the first terminal of the sampling resistor in the corresponding slip ring channel and the resistance sampling unit. The relay array control unit is connected to each first relay and each second relay, and is used for... The first relay of the i-th relay group and the second relay of the j-th relay group are turned on, while the remaining relays are turned off, so that the i-th slip ring channel and the j-th slip ring channel are connected in series to the resistance sampling circuit, where i=[1,2,……,n], j=[1,2,……,n], j≠i, and n is an integer; the signal conditioning unit is connected to the resistance sampling unit, and the signal conditioning unit is used to obtain a conditioned voltage signal based on the voltage output of the resistance sampling unit, and the conditioned voltage signal is used to calculate the contact resistance of the conductive slip ring; the processing unit is connected to the signal conditioning unit, and the processing unit is used to control the relay array control unit based on the conditioned voltage signal; The signal conditioning unit includes a first operational amplifier, a second operational amplifier, a first differential input circuit, and a second differential input circuit. The non-inverting input of the first operational amplifier is connected to a first terminal of the resistor sampling unit. The output of the first operational amplifier is connected to the second differential input circuit. The non-inverting input of the second operational amplifier is connected to the power supply of the resistor sampling unit. The output of the second operational amplifier is connected to the first differential input circuit. The inverting inputs of both the first and second operational amplifiers are grounded. The first differential input circuit and the second differential input circuit are used to output conditioned voltage signals. The first differential input circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, and a third operational amplifier. The first resistor is connected to the output terminal of the second operational amplifier and the inverting input terminal of the third operational amplifier. The second resistor is connected to the inverting input terminal and the output terminal of the third operational amplifier. The third resistor is connected to a reference voltage and the non-inverting input terminal of the third operational amplifier. The fourth resistor is connected to the non-inverting input terminal of the third operational amplifier and ground. The output terminal of the third operational amplifier outputs a first conditioned voltage signal. The second differential input circuit includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a fourth operational amplifier. The fifth resistor is connected to the output terminal of the first operational amplifier and the inverting input terminal of the fourth operational amplifier, respectively. The sixth resistor is connected to the inverting input terminal and the output terminal of the fourth operational amplifier, respectively. The seventh resistor is connected to the reference voltage and the non-inverting input terminal of the fourth operational amplifier, respectively. The eighth resistor is connected to the non-inverting input terminal of the fourth operational amplifier and ground, respectively. The output terminal of the fourth operational amplifier outputs a second conditioned voltage signal. The gain of both the first operational amplifier and the second operational amplifier is 1; The conductive slip ring contact resistance detection method based on self-constructed circuits includes: The processing unit controls the first relay of the i-th relay group and the second relay of the j-th relay group to be turned on through the relay array control unit, while the remaining relays are turned off; where i=[1,2,……,n], j=[1,2,……,n], j≠i, and n is an integer; according to Obtain the total contact resistance of the i-th slip ring channel and the j-th slip ring channel; where R ij This represents the combined contact resistance of the i-th and j-th slip ring channels. R i Let R be the contact resistance of the i-th slip ring channel to be determined. j R is the contact resistance of the j-th slip ring channel to be determined; c V is the resistance value of the sampling resistor. j V is the output voltage of the resistor sampling unit at the power supply terminal. c V is the output voltage of the resistance sampling unit at the first terminal of the sampling resistor; adj The voltage after the first conditioning step, V adc This is the voltage after the second conditioning; V ref G3 is the reference voltage; G3 is the gain of the third operational amplifier. , These are the resistance values ​​of the first, second, third, and fourth resistors, respectively; G4 is the gain of the fourth operational amplifier. , These are the resistance values ​​of the fifth, sixth, seventh, and eighth resistors, respectively. Processing unit controls relay array control unit to obtain The total value of the contact resistance, based on The total value of each contact resistance is used to obtain the contact resistance of any slip ring channel in order to complete the detection of the contact resistance of the conductive slip ring.

2. The method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit according to claim 1, characterized in that, The processing unit includes an ADC converter and a CPU processor. The ADC converter is connected to the signal conditioning unit and the CPU processor respectively, and the ADC converter is used to acquire digital signals based on the conditioned voltage signals. The CPU processor is connected to the relay array control unit, and the CPU processor is used to control the ADC converter and the relay array control unit based on the digital signals.

3. The method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit according to claim 2, characterized in that, The conductive slip ring contact resistance detection device based on self-constructed circuit also includes a communication unit, which is connected to the CPU processor. The communication unit is used to receive external control commands and output digital signals processed by the CPU processor.

4. The method for detecting the contact resistance of a conductive slip ring based on a self-constructed circuit according to claim 3, characterized in that, The communication unit may use an RS422 communication port.

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