Protection circuit for reducing electromagnetic interference of proportional amplification circuit caused by poor grounding of locomotive

Abstract

The utility model provides a protection circuit for reducing electromagnetic interference of a proportional amplification circuit caused by poor grounding of a locomotive, which is connected between the proportional amplification circuit and a grounding end of a locomotive body and comprises a diode, a capacitor and a proportional amplification circuit grounding loop. The diode and the capacitor are connected to a grounding line of a grounding loop of the proportional amplification circuit, and the diode and the capacitor comprise a diode and a capacitor which are connected in parallel; and the diode is in one-way conduction and reverse cut-off from the proportional amplification circuit to the grounding end of the vehicle body in the conduction and cut-off directions. According to the utility model, the circuit structure is simple and reasonable, the grounding condition of the wheeled locomotive proportional amplifier circuit is improved, the influence of external charge / interference on the amplifier loop is avoided, and the damage of the electrified non-grounding body of the wheeled vehicle to the amplifier loop is reduced; the safety of equipment and personnel is improved; the precision of the control circuit is improved, and more stable and accurate motion control is realized; manufacturing is easy, cost is low, and application and popularization are facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of proportional amplifier circuits, in particular to a protection circuit for reducing electromagnetic interference of proportional amplifier circuits caused by poor grounding of locomotives. Background Art

[0002] The amplifier is an electrical component that connects the electro-hydraulic proportional valve to the locomotive central control unit to achieve fast, smooth and precise motion control.

[0003] The amplifier converts the input reference signal generated by the locomotive central control unit into a current signal supplied to the proportional valve solenoid in proportion. Especially for high-performance proportional amplifiers, the output current is given to the proportional valve solenoid, and the closed-loop control of the output current and the position and pressure of the slide valve / cone valve core is achieved through feedback from corresponding types of detection sensors such as current, displacement, and pressure. Therefore, the proportional amplifier circuit needs to ensure that the power supply, voltage-type command signal, and various detection sensors are well shielded and grounded.

[0004] Conventional non-wheeled vehicles and machinery (track grounding) have good grounding conditions, and the proportional amplifier circuit on the non-wheeled vehicle can be well grounded.

[0005] However, wheeled vehicles and machinery do not have good grounding conditions when they are moving (tire grounding). Since the power supply, voltage command signal, sensor power supply and feedback signal on the wheeled locomotive cannot be well grounded, they are easily affected by the charged body and other electromagnetic interference. The body is prone to generate electrical interference beyond the limit, and it will be transmitted from the connecting wire of the amplifier circuit (connected to the body) to the inside of the proportional amplifier circuit, affecting the normal operation of the proportional amplifier, resulting in errors, reduced control accuracy, affecting the control performance, and even causing serious problems such as burning of the amplifier circuit, causing equipment and personal safety accidents.

[0006] Therefore, there is an urgent need to develop an accurate, stable and safe protection circuit for wheeled vehicles and machinery to reduce the electromagnetic interference of the proportional amplifier circuit caused by poor grounding, so as to solve the current problems of electromagnetic interference in the proportional amplifier circuit caused by poor grounding of wheeled vehicles and machinery, which reduces the control accuracy. Utility Model Content

[0007] In view of this, the purpose of the utility model is to design a protection circuit for reducing electromagnetic interference in a proportional amplifier circuit caused by poor grounding of a wheeled locomotive. A capacitor and a diode are added to the grounding loop of the proportional amplifier. The unidirectional conductivity of the diode is used to allow the voltage at the grounding end of the amplifier to pass through the diode to the vehicle body. The capacitor plays an isolation role in the bypass circuit and provides a low-impedance path for the parallel diode, thereby improving the grounding condition of the proportional amplifier circuit of the wheeled vehicle and machinery. The utility model is simple to manufacture, low-cost, and conducive to popularization and application.

[0008] The utility model provides a protection circuit for reducing electromagnetic interference of a proportional amplifier circuit caused by poor grounding of a locomotive, which is connected between the proportional amplifier circuit and the grounding terminal of the vehicle body and includes the following two parts: a diode and a capacitor, and a grounding loop of the proportional amplifier circuit; the diode and the capacitor are connected to the grounding line of the grounding loop of the proportional amplifier circuit, and the diode and the capacitor include: a diode and a capacitor, and the diode is connected in parallel with the capacitor;

[0009] The capacitor can be used as a bypass capacitor to store the electric charge of the vehicle body, forming a bypass circuit to play an isolation role, thereby preventing the electric charge of the vehicle body from forming direct current and directly being introduced into the proportional amplifier circuit, thereby destroying the proportional amplifier circuit;

[0010] After the diode is connected in parallel with the capacitor and connected to the ground terminal of the vehicle body, it can eliminate the static electricity accumulation at both ends of the capacitor and prevent the capacitor from being broken down.

[0011] The conduction and cutoff directions of the diode are one-way conduction from the proportional amplifier circuit (proportional amplifier) ​​to the vehicle body ground terminal and reverse cutoff. By using the unidirectional conductivity of the unidirectional diode, the voltage of the ground terminal of the proportional amplifier circuit (proportional amplifier) ​​reaches the vehicle body ground terminal through the diode, thereby improving the grounding condition of the proportional amplifier circuit.

[0012] Furthermore, the grounding loop of the proportional amplifier circuit includes: a power supply and command signal module, a shielding wire, and a proportional amplifier circuit. The power supply and command signal module is connected in series with the proportional amplifier circuit, and the shielding wire is arranged on the outside of the connecting wire between the power supply and command signal module and the proportional amplifier circuit.

[0013] Furthermore, the low level point of the shielding wire is set on a side close to the grounding end of the vehicle body. The low level point of the shielding wire cannot be set between the grounding loop of the proportional amplifier circuit and the parallel circuit of the diode and the capacitor to avoid interference of the low level point voltage of the shielding wire on the proportional amplifier circuit.

[0014] Furthermore, the power supply and command signal module includes: a power supply and a voltage-type command signal unit, the power supply is electrically connected to the voltage-type command signal unit, the voltage-type command signal unit is connected to the proportional amplifier circuit voltage signal, and the low level point of the power supply is set on a side close to the vehicle body grounding terminal.

[0015] The protection circuit of the utility model does not set the low level point of the power supply between the grounding loop of the proportional amplifier circuit and the parallel circuit of the diode and the capacitor, thereby avoiding the interference of the low level point voltage of the power supply on the proportional amplifier circuit.

[0016] Furthermore, the low level point of the voltage-type command signal unit is arranged on a side close to the ground terminal of the vehicle body.

[0017] The protection circuit does not set the low level point of the voltage type command signal unit between the proportional amplifier circuit grounding loop and the parallel circuit of the diode and the capacitor to avoid interference of the low level point voltage of the voltage type command signal unit on the proportional amplifier circuit.

[0018] Furthermore, the ground end of the shielding wire is grounded, and the shielding wire is suspended at one end of the proportional amplifier circuit and one end of the detection sensor element, thereby preventing current from being generated in the shielding wire and forming a current loop.

[0019] Furthermore, the diode is a unidirectional TVS transient voltage suppression diode.

[0020] The main feature of transient voltage suppression diode (TVS) is that under reverse application conditions, when subjected to a high-energy large pulse, its working impedance immediately drops to an extremely low conduction value, thereby allowing large current to pass through, while clamping the voltage at a predetermined level, and its response time is only 10-12 milliseconds, so it can effectively protect precision components in electronic circuits. The forward surge current allowed by TVS can reach 50-200A under the conditions of TA=250C, T=10ms. Unidirectional TVS is generally used in DC circuits and can be used to prevent overvoltage, resist interference, absorb surge power, etc.

[0021] Furthermore, the capacitor is a tantalum capacitor. The capacitance value of the tantalum capacitor is highly accurate and stable, and has a very low equivalent series resistance (ESR). The capacitor acts as a decoupling capacitor to filter out interference from the output signal of the proportional amplifier circuit, prevent the interference signal from returning to the proportional amplifier circuit, and provide a low impedance path for the parallel unidirectional TVS diode.

[0022] Furthermore, the unidirectional TVS transient voltage suppression diode adopts a patch TVS diode. The patch TVS diode is in a sheet shape, and compared with the corresponding general diode, it has a small volume, a small power dissipation, and other parameters do not change much.

[0023] Preferably, the reverse voltage value of the unidirectional TVS transient voltage suppression diode is set to 18V, and the capacitance value of the capacitor is set to 10μF.

[0024] Furthermore, the ground terminal of the power supply, the ground terminal of the voltage-type command signal unit, the ground terminal of the detection sensor element, and the ground terminal of the shielding wire are all arranged at the remote ground terminal of the proportional amplifier circuit to prevent the ground terminal voltage of the power supply, the voltage-type command signal unit, the detection sensor element, and the shielding wire from interfering with the proportional amplifier circuit.

[0025] Compared with the prior art, the beneficial effects of the utility model are:

[0026] The utility model has a simple and reasonable structure and strong integrity of a protection circuit for reducing electromagnetic interference in a proportional amplifier circuit caused by poor grounding of a locomotive. By adding a capacitor and a diode in a grounding loop of the proportional amplifier, the unidirectional conductivity of the diode is utilized to allow the voltage at the grounding end of the amplifier to pass through the diode to the vehicle body. The capacitor plays an isolating role in the bypass circuit and provides a low-impedance path for the parallel diode, thereby improving the grounding condition of the proportional amplifier circuit of wheeled vehicles and machinery, avoiding the influence of external charges / interference on the operation of the amplifier circuit, and reducing the damage to the amplifier circuit circuit caused by the non-grounded body of the wheeled vehicle due to the charge; improving the safety of equipment and personnel; compared with the existing directly grounded amplifier circuit, the accuracy of the control circuit is effectively improved, and more stable and precise motion control is achieved; and the protection circuit is simple to manufacture, low in cost, and has broad prospects for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those skilled in the art. The accompanying drawings are only for the purpose of illustrating the preferred embodiment and are not to be considered as limiting the present invention.

[0028] In the attached picture:

[0029] Figure 1 This is the overall structure diagram of the protection circuit for reducing electromagnetic interference of the proportional amplifier circuit caused by poor grounding of the locomotive in the utility model;

[0030] Figure 2 This is a schematic diagram of the electrical connection of a diode and a capacitor according to an embodiment of the present utility model.

[0031] The symbols in the accompanying drawings are:

[0032] 1. Proportional amplifier circuit, 2. Diode and capacitor,

[0033] 3. Shielded wire, 4. Power supply and command signal module,

[0034] 5. Diode, 6. Capacitor. DETAILED DESCRIPTION

[0035] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0036] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0037] It should be understood that although the terms first, second, and third may be used in the present disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0038] The utility model provides a protection circuit for reducing electromagnetic interference of the proportional amplifier circuit caused by poor locomotive grounding, which is connected between the proportional amplifier circuit and the grounding terminal of the vehicle body. Figure 1 , 2 As shown, it includes the following two parts: a diode and a capacitor 2, and a proportional amplifier circuit grounding loop; the diode and the capacitor 2 are connected to the grounding line of the proportional amplifier circuit grounding loop,

[0039] The diode and capacitor 2 includes: a diode 5 and a capacitor 6, wherein the diode 5 and the capacitor 6 are connected in parallel;

[0040] The grounding loop of the proportional amplifier circuit includes: a power supply and command signal module 4, a shielding wire 3, and a proportional amplifier circuit 1. The power supply and command signal module 4 is connected in series with the proportional amplifier circuit 1, and the shielding wire 3 is set on the outside of the connecting wire between the power supply and command signal module 4 and the proportional amplifier circuit 1. The low level point of the shielding wire 3 is set on the side close to the grounding end of the vehicle body. The low level point of the shielding wire 3 is not set between the grounding loop of the proportional amplifier circuit and the parallel circuit of the diode and the capacitor 2, so as to avoid the interference of the low level point voltage of the shielding wire 3 on the proportional amplifier circuit 1. The grounding end of the shielding wire 3 is grounded, and the shielding wire 3 is suspended at one end of the proportional amplifier circuit and at one end of the detection sensor element, so as to avoid the generation of current in the shielding wire 3 and the formation of a current loop.

[0041] The power supply and command signal module 2 includes: a power supply and a voltage command signal unit. The power supply is electrically connected to the voltage command signal unit, and the voltage command signal unit is voltage-connected to the proportional amplifier circuit 1. The low level point of the power supply is set on the side close to the grounding end of the vehicle body. In this embodiment, the protection circuit does not set the low level point of the power supply between the grounding loop of the proportional amplifier circuit and the parallel circuit of the diode and the capacitor 2, thereby avoiding the interference of the low level point voltage of the power supply on the proportional amplifier circuit 1.

[0042] The low level point of the voltage type command signal unit is set on the side close to the ground terminal of the vehicle body. The low level point of the voltage type command signal unit is not set between the ground loop of the proportional amplifier circuit and the parallel circuit of the diode and the capacitor 2 to avoid the interference of the low level point voltage of the voltage type command signal unit on the proportional amplifier circuit 1.

[0043] In this embodiment, the ground terminal of the power supply, the ground terminal of the voltage-type command signal unit, the ground terminal of the detection sensor element, and the ground terminal of the shielding wire are all arranged at the remote ground terminal of the proportional amplifier circuit 1, which effectively prevents the ground terminal voltage of the power supply, the voltage-type command signal unit, the detection sensor element, and the shielding wire from interfering with the proportional amplifier circuit 1.

[0044] Capacitor 6 acts as a bypass capacitor, which can store the charged charge of the vehicle body, forming a bypass circuit to play an isolation role, thereby preventing the charged charge of the vehicle body from forming a direct current directly introduced into the interior of the proportional amplifier circuit 1, thereby destroying the proportional amplifier circuit 1; diode 5 is connected to the ground terminal of the vehicle body after being connected in parallel with capacitor 6, which can eliminate the static electricity accumulation of charge at both ends of capacitor 6 and prevent capacitor 6 from being broken down.

[0045] The conduction and cutoff directions of the diode 5 are unidirectional conduction from the proportional amplifier circuit 1 to the vehicle body ground terminal and reverse cutoff. By using the unidirectional conductivity of the unidirectional diode, the voltage at the ground terminal of the proportional amplifier circuit 1 reaches the vehicle body ground terminal through the diode 5, thereby improving the grounding condition of the proportional amplifier circuit 1.

[0046] In this embodiment, diode 5 is a SMD TVS diode with a reverse voltage of 18V; capacitor 6 is a tantalum capacitor with a capacitance of 10μF. The SMD TVS diode is small in size and has a small power dissipation; the capacitance value of the tantalum capacitor is highly accurate and stable, and has a very low ESR. Capacitor 6 acts as a decoupling capacitor to filter out interference from the output signal of the proportional amplifier circuit 1, prevent the interference signal from returning to the proportional amplifier circuit 1, and provide a low impedance path for the parallel unidirectional TVS diode with a reverse voltage of 18V.

[0047] The protection circuit provided in this embodiment for reducing electromagnetic interference of the proportional amplifier circuit caused by poor grounding of the locomotive has a simple and reasonable structure and strong integrity. By adding a capacitor and a diode in the grounding loop of the proportional amplifier, the unidirectional conductivity of the diode is used to allow the voltage at the grounding end of the amplifier to pass through the diode to the vehicle body. The capacitor plays an isolation role in the bypass circuit and provides a low-impedance path for the parallel diode, thereby improving the grounding condition of the proportional amplifier circuit of the wheeled vehicle and machinery, avoiding the influence of external charge / interference on the operation of the amplifier circuit, and reducing the damage to the amplifier circuit loop due to the charge of the non-grounded body of the wheeled vehicle; improving the safety of equipment and personnel; compared with the existing directly grounded amplifier circuit, the accuracy of the control circuit is effectively improved, and more stable and precise motion control is achieved; and the protection circuit is simple to manufacture, low cost, and has broad prospects for promotion and application.

[0048] So far, the technical solution of the utility model has been described in conjunction with the preferred embodiments shown in the accompanying drawings, but it is easy for those skilled in the art to understand that the protection scope of the utility model is obviously not limited to these specific embodiments. Without departing from the principle of the utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the utility model.

[0049] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model may have various modifications and changes. Any modification, replacement, and improvement made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A protection circuit for reducing electromagnetic interference in a proportional amplifier circuit caused by poor grounding of a locomotive, characterized in that: Connected between the proportional amplifier circuit and the vehicle body grounding terminal, including the following two parts: a diode and a capacitor, and a proportional amplifier circuit grounding loop; the diode and the capacitor are connected to the grounding line of the proportional amplifier circuit grounding loop, the diode and the capacitor include: a diode and a capacitor, the diode and the capacitor are connected in parallel; The conducting and cutting-off directions of the diode are one-way conduction from the proportional amplifier circuit to the vehicle body ground terminal and reverse cutting-off.

2. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 1, characterized in that: The grounding loop of the proportional amplifier circuit includes: a power supply and command signal module, a shielding wire, and a proportional amplifier circuit. The power supply and command signal module is connected in series with the proportional amplifier circuit, and the shielding wire is arranged on the outside of the connecting wire between the power supply and command signal module and the proportional amplifier circuit.

3. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 2, characterized in that: The power supply and command signal module includes: a power supply and a voltage-type command signal unit. The power supply is electrically connected to the voltage-type command signal unit. The voltage-type command signal unit is connected to the proportional amplifier circuit voltage signal. The low level point of the power supply is set on a side close to the vehicle body grounding terminal.

4. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 3, characterized in that: The low level point of the voltage type command signal unit is arranged on a side close to the grounding end of the vehicle body.

5. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 2, characterized in that: The low level point of the shielding line is arranged on a side close to the grounding end of the vehicle body.

6. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 3, characterized in that: The grounding end of the shielding wire is grounded, and the shielding wire is suspended at one end of the proportional amplifier circuit and one end of the detection sensor element.

7. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 6, characterized in that: The grounding terminal of the power supply, the grounding terminal of the voltage-type command signal unit, the grounding terminal of the detection sensor element, and the grounding terminal of the shielding wire are all arranged at the remote grounding terminal of the proportional amplifier circuit.

8. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 1, characterized in that: The diode is a unidirectional TVS transient voltage suppression diode.

9. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 8, characterized in that: The capacitor is a tantalum capacitor.

10. The protection circuit for reducing electromagnetic interference of proportional amplifier circuit caused by poor grounding of locomotive according to claim 8, characterized in that: The unidirectional TVS transient voltage suppression diode adopts a surface-mount TVS diode.

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