Contactor and control method thereof

Abstract

The present disclosure relates to a contactor capable of achieving better coil maintenance power consumption control and a control method thereof. The control method of the contactor includes: obtaining a pull-in current of a coil of the contactor under a control voltage; determining a pull-in starting current according to the obtained pull-in current; determining a gravity component of a resistance system according to the pull-in starting current based on a corresponding relationship between the pull-in starting current and the gravity component; and determining a maintenance current of the contactor according to the gravity component and a spring resistance of the resistance system.

Description

Technical Field

[0001] This disclosure relates to contactors and control methods thereof. Background Technology

[0002] In traditional designs, the contactor's engagement and holding characteristics remain unchanged once the design is finalized. A single coil drive strategy can meet the needs of all operating conditions, but this also means that for most non-most demanding applications, the coil's driving capability is excessive, resulting in wasted contactor holding power consumption. Summary of the Invention

[0003] In view of the above, this disclosure provides a contactor and its control method that can achieve better coil holding power consumption control.

[0004] According to one aspect of the present disclosure, a control method for a contactor is provided, comprising: acquiring the pull-in current of the contactor coil under a control voltage; determining a pull-in starting current based on the acquired pull-in current; determining the gravity component based on the pull-in starting current and the gravity component of a resistance system; and determining the holding current of the contactor based on the gravity component and the spring resistance of the resistance system.

[0005] Optionally, determining the holding current of the contactor based on the gravitational component and the spring resistance of the resistance system includes: determining the total resistance of the resistance system based on the gravitational component and the spring resistance of the resistance system; determining the holding electromagnetic force of the contactor as the total resistance plus a predetermined margin; and determining the holding current based on the correspondence between the holding electromagnetic force and the holding current.

[0006] Optionally, the method further includes a step of determining the correspondence between the pull-in starting current and the gravitational component of the resistance system, including: obtaining multiple pull-in currents of the contactor coil for multiple different gravitational components; determining multiple pull-in starting currents corresponding to the multiple different gravitational components based on the multiple pull-in currents; and determining the correspondence between the pull-in starting current and the gravitational component of the resistance system based on the multiple different gravitational components and the multiple pull-in starting currents.

[0007] Optionally, obtaining multiple pull-in currents of the contactor coil for multiple different gravity components includes: establishing a model of the electromagnet based on the structure of the electromagnet of the contactor, and assigning material performance parameters to the model of the electromagnet; establishing a model of the control circuit of the contactor; and, based on the model of the electromagnet and the model of the control circuit, adjusting the gravity component through simulation to obtain the pull-in current of the contactor coil under different gravity components.

[0008] Optionally, the method further includes a step of determining the correspondence between the sustaining electromagnetic force and the sustaining current, including: obtaining multiple sustaining currents of the contactor coil for multiple different sustaining electromagnetic forces; and determining the correspondence between the sustaining electromagnetic force and the sustaining current based on the different sustaining electromagnetic forces and the multiple sustaining currents.

[0009] Optionally, obtaining multiple sustaining currents of the contactor coil for multiple different sustaining electromagnetic forces includes: establishing a model of the electromagnet based on the structure of the electromagnet of the contactor, and assigning material performance parameters to the model of the electromagnet; establishing a model of the control circuit of the contactor; and adjusting the sustaining electromagnetic force through simulation based on the model of the electromagnet and the model of the control circuit, thereby obtaining the sustaining current of the contactor coil under different sustaining electromagnetic forces.

[0010] Optionally, the multiple different gravity components are obtained by using different contactor installation angles.

[0011] Optionally, it also includes: supplementing the correspondence between the pull-in starting current and the gravitational component of the resistance system by interpolation.

[0012] Optionally, it also includes: supplementing the correspondence between the sustaining electromagnetic force and the sustaining current by interpolation.

[0013] Optionally, it may also include: pulse-width modulating the control voltage to adjust the current of the contactor coil to a determined sustaining current.

[0014] Optionally, it further includes: detecting the sustaining current of the contactor coil; and when the sustaining current of the contactor coil is detected to exceed a predetermined threshold, pulse-width modulating the control voltage to increase the current flowing through the contactor coil.

[0015] According to another aspect of the present disclosure, a contactor is provided, comprising: a current acquisition unit for acquiring the pull-in current of the contactor coil under a control voltage; and a processing unit configured to: determine a pull-in starting current based on the acquired pull-in current; determine the gravity component based on the pull-in starting current and the gravity component of the resistance system; and determine the holding current of the contactor based on the gravity component and the spring resistance of the resistance system.

[0016] Optionally, the processing unit is configured to determine the holding current of the contactor based on the gravitational component and the spring resistance of the resistance system, including: determining the total resistance of the resistance system based on the gravitational component and the spring resistance of the resistance system; determining the holding electromagnetic force of the contactor as the total resistance plus a predetermined margin; and determining the holding current based on the correspondence between the holding electromagnetic force and the holding current.

[0017] Optionally, the processing unit is configured to pulse-width modulate the control voltage to adjust the current of the contactor coil to a determined sustaining current.

[0018] Optionally, the processing unit is configured to: detect the sustaining current of the contactor coil; and when the sustaining current of the contactor coil exceeds a predetermined threshold, pulse-width modulate the control voltage to increase the current flowing through the contactor coil.

[0019] According to embodiments of this disclosure, better coil sustaining power consumption control can be achieved. Attached Figure Description

[0020] These and / or other aspects, features, and advantages of this disclosure will become clearer and more readily understood from the following description of embodiments in conjunction with the accompanying drawings, wherein:

[0021] Figure 1 This is a flowchart of a contactor control method according to an embodiment of the present disclosure.

[0022] Figure 2 This is a flowchart of the steps for determining the holding current of a contactor according to an embodiment of the present disclosure.

[0023] Figure 3 This is a flowchart of the steps for determining the correspondence between the pull-in starting current and the gravitational component of the resistance system according to an embodiment of the present disclosure.

[0024] Figure 4 This is an example diagram of multiple pull-in currents under multiple different gravity components according to embodiments of the present disclosure.

[0025] Figure 5 This is an example diagram showing the correspondence between the pull-in starting current and the gravitational component of the resistance system according to an embodiment of the present disclosure.

[0026] Figure 6 This is a flowchart of the steps for determining the correspondence between the sustaining electromagnetic force and the sustaining current according to an embodiment of the present disclosure.

[0027] Figure 7 This is an example diagram illustrating the correspondence between the sustaining electromagnetic force and the sustaining current according to embodiments of the present disclosure.

[0028] Figure 8 This is a flowchart of a contactor control method according to another embodiment of the present disclosure.

[0029] Figure 9 This is a schematic block diagram of a contactor according to an embodiment of the present disclosure. Detailed Implementation

[0030] The present disclosure will now be described in detail with reference to exemplary embodiments thereof. However, the present disclosure is not limited to the embodiments described herein, which may be implemented in many different forms. The described embodiments are provided only to make the present disclosure thorough and complete, and to fully convey the concept of the present disclosure to those skilled in the art. Features of the various embodiments described may be combined with or substituted for each other, unless expressly excluded or should be excluded based on the context.

[0031] A contactor is a switching device used to connect and disconnect circuits. A contactor can reliably engage when a circuit needs to be connected and quickly disengage when a circuit needs to be disconnected, based on control commands.

[0032] Traditional contactors rely on a pre-designed, sufficiently large electromagnetic force to ensure reliable contact engagement. This pre-designed electromagnetic force typically considers factors such as shock and vibration resistance, and fluctuations in product parameters, and remains unchanged after the design is finalized. To guarantee this sufficiently large electromagnetic force, a large holding current is required. This single-coil drive strategy can meet the needs of all operating conditions, such as various installation orientations of the contactor. However, this also means that for most non-most demanding operating scenarios, the coil's drive capability is excessive, resulting in wasted contactor holding power consumption.

[0033] In the contactor coil's engagement and maintenance, the main resistances are spring resistance and gravitational force. In this disclosure, the total resistance experienced by the contactor coil in engagement and maintenance is referred to as the resistance system. The gravitational component in the resistance system mainly originates from the weight of the moving iron core. The contribution of the moving iron core's weight to the resistance system varies depending on the contactor's installation orientation. For example, when the contactor's installation method causes the direction of the moving iron core's weight to be completely opposite to the direction of the engagement force, the weight of the moving iron core becomes entirely the gravitational component of the resistance system. If the direction of the moving iron core's weight is not completely opposite to the direction of the engagement force, but has a certain angular deviation, only the component of the moving iron core's weight in the opposite direction of the engagement force becomes the gravitational component of the resistance system. Therefore, even for the same contactor, different installation orientations result in different gravitational components, leading to different total resistances, and consequently requiring different engagement and maintenance electromagnetic forces.

[0034] This disclosure allows for the determination of different sustaining electromagnetic forces and sustaining currents for different gravitational components, thereby enabling the application of different sustaining currents to the coil when the contactor is in different installation orientations, instead of using a uniform sustaining current, thereby reducing the sustaining power consumption of the contactor.

[0035] During the contactor's activation process, a predetermined control voltage is applied to the contactor coil, causing the activation current to gradually increase from 0. After reaching a peak value (called the activation starting current), the current suddenly decreases, drops to a trough, and then continues to increase before eventually stabilizing. Once the contactor coil is stably activated, a sustaining current can be applied to maintain the activated state. This change in activation current is determined by the contactor's inherent activation characteristics and is related to its resistance system. For example, the contactor's activation starting current corresponds to its resistance system or the gravitational component within that system.

[0036] By plotting the pull-in current versus time curves for the same or similar contactors under different gravitational components, it can be observed that the larger the gravitational component (resistance), the larger the pull-in starting current. Therefore, the correspondence between the pull-in starting current and the gravitational component can be obtained through simulation or testing. After obtaining this correspondence, the actual gravitational component of the contactor can be determined by measuring its pull-in current after actual installation and determining the pull-in starting current. Subsequently, the required holding electromagnetic force and holding current of the contactor can be determined based on this actual gravitational component. The resulting holding current takes into account the actual installation orientation of the contactor, thus allowing for more precise control of holding power consumption.

[0037] When determining the holding electromagnetic force and holding current based on the gravitational component, the total resistance can be determined based on the gravitational component and the spring resistance. The holding electromagnetic force is then obtained by adding a predetermined margin to the total resistance. The holding current is then determined based on the correspondence between the holding electromagnetic force and the holding current. The predetermined margin can be determined before the contactor leaves the factory, and can take into account factors such as conventional vibration resistance, friction between components, and / or fluctuations in product parameters.

[0038] The holding current determined according to the above-described method of this disclosure can save holding energy while ensuring normal operation of the contactor. Furthermore, optionally, if the contactor is subjected to an unexpected impact during normal use, the impact can be detected by detecting changes in the holding current. When the contactor is subjected to a sudden impact, the gap between the moving and stationary iron cores may change from a gapless state to one with an air gap. At this time, the magnetic reluctance increases and the inductance decreases, thereby increasing the current. Therefore, when the holding current of the contactor coil is detected to exceed a predetermined threshold, it can be known that the contactor has lost its stable engaged state due to an impact. At this time, the current flowing through the contactor coil can be increased by pulse width modulation of the control voltage, making the holding electromagnetic force greater than a predetermined value, thereby enabling the contactor to be stably engaged again. Thus, the contactor according to the embodiments of this disclosure can not only save holding energy during normal use but also maintain a stable engaged state when subjected to unexpected impacts.

[0039] Figure 1 This is a flowchart of a contactor control method according to an embodiment of the present disclosure.

[0040] In step S1, the pull-in current of the contactor coil under the control voltage is obtained. The magnitude of this control voltage can be predetermined according to the characteristics of the contactor. As mentioned above, the pull-in current of the contactor coil is a current that varies with time. By obtaining the pull-in current over time, the trend of the pull-in current over time can be obtained.

[0041] In step S2, the pull-in starting current is determined based on the acquired pull-in current. For example, a curve showing the pull-in current changing over time can be plotted based on the acquired pull-in current; the first peak of the curve is the pull-in starting current. The curve showing the pull-in current changing over time can be as follows: Figure 4 As shown. Figure 4 The first peak value before the medium current decreases is the pull-in starting current value. Alternatively, instead of plotting a curve, you can judge whether the data decreases in time sequence, and the value before the initial decrease is the pull-in starting current value.

[0042] In step S3, the gravity component is determined based on the correspondence between the pull-in starting current and the gravitational component of the resistance system. For example, the pull-in starting current obtained in step S2 can be substituted into the above correspondence to obtain the gravity component at this time. The correspondence between the pull-in starting current and the gravitational component of the resistance system can be stored in the contactor's memory after pre-testing or simulating the contactor or this type of contactor. The method for determining the correspondence between the pull-in starting current and the gravitational component of the resistance system will be explained in detail below. This correspondence can be in the form of a correspondence table between the pull-in starting current and the gravity component, or it can be in the form of a fitted formula.

[0043] In step S4, the holding current of the contactor is determined based on the gravitational component and the spring resistance of the resistance system. The resistance system mainly includes the gravitational component and the spring resistance. For a specific contactor, the spring resistance is fixed in the holding state. Therefore, after determining the gravitational component, the total resistance of the resistance system can be determined based on the gravitational component and the spring resistance. Based on the total resistance, the holding electromagnetic force of the contactor can be determined. Generally, the holding electromagnetic force needs to be greater than a certain value of the total resistance. The holding current corresponds to the holding electromagnetic force, thus the holding current can be further determined. Of course, when determining the holding current, in addition to considering the gravitational component and the spring resistance, other factors such as friction can also be considered.

[0044] According to the contactor control method of the present disclosure, the determination of the holding current not only takes into account the influence of spring resistance, but also the influence of the actual gravity component. Therefore, targeted control can be performed so that the holding current matches the changes in gravity component under different operating conditions, making the holding current relatively small, thereby achieving better coil holding power consumption control.

[0045] Figure 2 This is a flowchart of the steps for determining the holding current of a contactor according to an embodiment of the present disclosure.

[0046] In step S41, the total resistance of the resistance system is determined based on the gravitational component and the spring resistance of the resistance system. For example, the total resistance can be obtained by superimposing the gravitational component and the spring resistance of the resistance system. Alternatively, other factors such as friction can be considered in addition to the gravitational component and the spring resistance to determine the total resistance.

[0047] In step S42, the holding electromagnetic force of the contactor is determined to be the total resistance plus a predetermined margin. The predetermined margin can be pre-determined and can be based on at least one of the following factors: conventional vibration resistance, friction between components, fluctuations in product parameters, etc. The predetermined margin is determined only to ensure that the contactor maintains a stable engaged state during normal operation, thus enabling stable operation of the contactor at a relatively small holding current.

[0048] In step S43, the holding current is determined based on the correspondence between the holding electromagnetic force and the holding current. For example, the holding electromagnetic force obtained in step S42 can be substituted into the above correspondence to obtain the holding current. The correspondence between the holding electromagnetic force and the holding current can be stored in the contactor's memory after pre-testing or simulating the contactor or this type of contactor. The method for determining the correspondence between the holding electromagnetic force and the holding current will be explained in detail below. This correspondence can be in the form of a correspondence table between the holding electromagnetic force and the holding current, or it can be in the form of a fitted formula.

[0049] Figure 3This is a flowchart of the steps for determining the correspondence between the pull-in starting current and the gravitational component of the resistance system according to an embodiment of the present disclosure.

[0050] In step S301, multiple pull-in currents of the contactor coil are obtained for multiple different gravity components. Different gravity components can be obtained, for example, by different contactor mounting angles. Specifically, the contactor can be mounted by rotating it by a predetermined angle, gravity can be measured to obtain the corresponding gravity component, and the current can be measured under different gravity components to obtain the corresponding contactor coil pull-in current. Furthermore, a finite element simulation model can be used to simulate the changing trend of the pull-in current under different gravity components. For example, obtaining multiple pull-in currents of the contactor coil for multiple different gravity components may include: establishing a model of the electromagnet based on the structure of the contactor's electromagnet, assigning material performance parameters to the electromagnet model; establishing a model of the contactor's control circuit; and adjusting the gravity component through simulation based on the electromagnet model and the control circuit model to obtain the contactor coil pull-in current under different gravity components. Specifically, a three-dimensional solid model of the electromagnet of the contactor coil can be established in finite element simulation software, and corresponding material property parameters can be assigned to each solid part. Based on electromagnetic principles, corresponding boundary conditions (e.g., the equations or laws satisfied by the electromagnetic fields on both sides of the interface of different media) can be set to simulate reality. Then, a circuit model can be established based on the actual control circuit. Under the excitation of the control voltage, the motion process of the moving iron core can be calculated based on the motion principle. Simulations can be performed for different gravity components, thereby obtaining the curves of the contactor coil current changing with time under different gravity components. Figure 4 This is an example diagram of multiple pull-in currents under different gravity components according to embodiments of the present disclosure. It is an example diagram illustrating the changing trends of the pull-in current under different gravity components, obtained by establishing a finite element simulation model after applying a control voltage to the F2600 contactor. Figure 4 In the diagram, the horizontal axis represents time, and the vertical axis represents the pull-in current flowing through the contactor coil. Figure 4 It can be seen that the pull-in current starts from 0, increases after reaching the first peak, then decreases, increases again after reaching a trough, and finally stabilizes. The first peak is the pull-in initiation current. Similarly, if the pull-in current is obtained using actual measurement methods, a similar result can be obtained. Figure 4 The result.

[0051] In step S302, multiple pull-in currents corresponding to multiple different gravitational components are determined based on the multiple pull-in currents. For example, a curve showing the trend of the pull-in current over time can be plotted based on the pull-in currents obtained for multiple different gravitational components, such as... Figure 4As shown, the first peak of the curve corresponding to each gravitational component is the pull-in current under that gravitational component. Optionally, instead of plotting curves, the pull-in current can be determined sequentially over time to see if it decreases; the value before the pull-in current initially decreases is the pull-in current value.

[0052] In step S303, the correspondence between the pull-in starting current and the gravitational components of the resistance system is determined based on multiple different gravitational components and multiple pull-in starting currents. This correspondence can be in the form of a table showing the relationship between the pull-in starting current and the gravitational components, or it can be in the form of a fitted formula. For example, a table can be created based on the multiple pull-in starting currents determined in step S302 and their corresponding gravitational components, or a fitted formula can be obtained through data fitting. Figure 5 This is an example diagram showing the correspondence between the pull-in starting current and the gravitational component of the resistance system according to an embodiment of the present disclosure. Figure 5 The horizontal axis represents the pull-in starting current, and the vertical axis represents the gravitational component; the two are approximately linearly related. Furthermore, interpolation can be used to supplement the correspondence between the pull-in starting current and the gravitational component of the resistance system. For example, if only 10 pull-in starting currents are obtained for 10 gravitational components, interpolation can be performed between adjacent gravitational components and adjacent pull-in starting currents to obtain more gravitational components and pull-in starting currents, thereby obtaining a more refined correspondence. After obtaining the correspondence between the pull-in starting current and the gravitational component of the resistance system in step S303, it can be stored in the contactor's memory so that the contactor can use it to obtain the actual gravitational component, as described in step S3.

[0053] Figure 6 This is a flowchart of the steps for determining the correspondence between the sustaining electromagnetic force and the sustaining current according to an embodiment of the present disclosure.

[0054] In step S601, multiple holding currents of the contactor coil are obtained for multiple different holding electromagnetic forces. For example, the holding current can be adjusted by pulse width modulation of the control voltage, thereby adjusting the holding electromagnetic force. The holding electromagnetic force is measured, and the holding current is measured under different holding electromagnetic forces to obtain the corresponding holding current of the contactor coil. Alternatively, a finite element simulation model can be used to simulate the changes in holding current under different holding electromagnetic forces. For example, obtaining multiple holding currents of the contactor coil for multiple different holding electromagnetic forces may include: establishing a model of the electromagnet based on the structure of the electromagnet of the contactor, assigning material property parameters to the electromagnet model; establishing a model of the control circuit of the contactor; and adjusting the holding electromagnetic force through simulation based on the electromagnet model and the control circuit model to obtain the holding current of the contactor coil under different holding electromagnetic forces. Specifically, a three-dimensional solid model of the electromagnet of the contactor coil can be established in finite element simulation software, and corresponding material property parameters can be assigned to each solid part. Based on electromagnetic principles, corresponding boundary conditions (e.g., the equations or laws satisfied by the electromagnetic fields on both sides of the interface of different media) can be set to simulate reality. Then, a circuit model can be established based on the actual control circuit, and simulation can be performed for different holding electromagnetic forces, thereby obtaining the curve of the correspondence between holding electromagnetic force and holding current.

[0055] In step S602, the correspondence between the sustaining electromagnetic force and the sustaining current is determined based on different sustaining electromagnetic forces and multiple sustaining currents. This correspondence can be in the form of a correspondence table between sustaining electromagnetic forces and multiple sustaining currents, or it can be in the form of a fitted formula. For example, a correspondence table can be created based on the multiple sustaining currents and their corresponding multiple sustaining electromagnetic forces obtained in step S601, or a fitted formula can be obtained by data fitting. Figure 7 This is an example diagram illustrating the correspondence between the sustaining electromagnetic force and the sustaining current according to embodiments of the present disclosure. Figure 7 The horizontal axis represents the electromagnetic force, and the vertical axis represents the sustaining current. Furthermore, the correspondence between the sustaining electromagnetic force and the sustaining current can be supplemented by interpolation. For example, if only 10 sustaining currents are obtained for 10 sustaining electromagnetic forces, interpolation can be performed between sustaining electromagnetic forces and between adjacent sustaining currents to obtain more sustaining electromagnetic forces and sustaining currents, thereby obtaining a more refined correspondence. After obtaining the correspondence between sustaining electromagnetic force and sustaining current in step S602, it can be stored in the contactor's memory so that the contactor can use it to determine the sustaining current, as described in steps S4 and S43.

[0056] Figure 8 This is a flowchart of a contactor control method according to another embodiment of the present disclosure.

[0057] like Figure 8As shown, the control method of this disclosure, in addition to Figure 1 In addition to steps S1-S4 shown, step S5 may also be included, which involves pulse-width modulating the control voltage to adjust the current of the contactor coil to a predetermined sustaining current. That is, the current of the contactor coil can be adjusted to a predetermined sustaining current by adjusting the duty cycle of the control voltage.

[0058] Furthermore, the control method of this disclosure may also include step S6, detecting the holding current of the contactor coil; when the holding current of the contactor coil exceeds a predetermined threshold, pulse-width modulation is applied to the control voltage to increase the current flowing through the contactor coil. Step S6 can maintain a stable engaged state even when the contactor is subjected to an unexpected impact. If the contactor is subjected to an unexpected impact during normal use, the impact can be detected by detecting changes in the holding current. When the contactor is subjected to a sudden impact, the gap between the moving and stationary iron cores may change from a gapless state to one with an air gap. At this time, the magnetic reluctance increases and the inductance decreases, thereby increasing the current. Therefore, when the holding current of the contactor coil is detected to exceed the predetermined threshold, it can be known that the contactor has lost its stable engaged state due to the impact. At this time, the current flowing through the contactor coil can be increased by pulse-width modulation of the control voltage, making the holding electromagnetic force greater than a predetermined value, thereby enabling the contactor to be stably engaged again. Thus, the contactor according to the embodiments of this disclosure can not only save holding energy during normal use, but also maintain a stable engaged state when subjected to unexpected impacts. After the contactor re-engages stably, the holding current can be restored to the value determined in step S4.

[0059] Figure 9 This is a schematic block diagram of a contactor according to an embodiment of the present disclosure.

[0060] Figure 9 The contactor 1 shown may include a current acquisition unit 11 and a processing unit 12.

[0061] The current acquisition unit 11 is used to acquire the pull-in current of the contactor coil under the control voltage.

[0062] The processing unit 12 can be configured to perform other steps described in the contactor control method of this disclosure, for details of which are given above in the description of the contactor control method and will not be repeated hereafter.

[0063] Where there is no conflict, each unit in this disclosure can be separated into multiple sub-units, multiple units can be combined into one unit, the parallel and inclusion relationships between units can be changed, and the order of each method step can be changed.

[0064] The block diagrams of circuits, devices, apparatuses, equipment, and systems disclosed herein are merely illustrative examples and are not intended to require or imply that connections, arrangements, or configurations must be made in the manner shown in the block diagrams. As those skilled in the art will recognize, these circuits, devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner that achieves the desired purpose.

[0065] Those skilled in the art should understand that the specific embodiments described above are merely examples and not limitations. Various modifications, combinations, partial combinations, and substitutions can be made to the embodiments of this disclosure according to design requirements and other factors, as long as they are within the scope of the appended claims or their equivalents, and thus fall within the scope of the rights to be protected by this disclosure.

[0066] According to embodiments of this disclosure, the methods described above can also be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program tangibly embodied on a machine-readable medium, the computer program containing program code for performing the methods described above.

Claims

1. A method for controlling a contactor, comprising: Obtain the pull-in current of the contactor coil under the control voltage; Determine the pull-in start current based on the obtained pull-in current; Based on the correspondence between the pull-in starting current and the gravitational component of the resistance system, the gravitational component is determined according to the pull-in starting current, wherein the resistance system is the sum of the resistances experienced by the contactor coil during pull-in maintenance, and the gravitational component is associated with the installation orientation of the contactor. The correspondence is obtained through simulation or testing. as well as The holding current of the contactor is determined based on the gravity component and the spring resistance of the resistance system.

2. The control method of claim 1, wherein determining the holding current of the contactor based on the gravity component and the spring resistance of the resistance system comprises: The total resistance of the resistance system is determined based on the gravity component and the spring resistance of the resistance system. The holding electromagnetic force of the contactor is determined to be the total resistance plus a predetermined margin. as well as Based on the correspondence between the sustaining electromagnetic force and the sustaining current, the sustaining current is determined according to the sustaining electromagnetic force.

3. The control method as described in claim 1, further comprising the step of determining the correspondence between the pull-in starting current and the gravitational component of the resistance system, including: Multiple pull-in currents of the contactor coil are obtained for multiple different gravity components; Based on the plurality of pull-in currents, determine a plurality of pull-in start currents corresponding to the plurality of different gravity components; as well as The correspondence between the pull-in starting current and the gravitational component of the resistance system is determined based on the multiple different gravitational components and the multiple pull-in starting currents.

4. The control method as described in claim 3, wherein obtaining multiple pull-in currents of the contactor coil for multiple different gravity components includes: Based on the structure of the electromagnet of the contactor, a model of the electromagnet is established, and material property parameters are assigned to the model of the electromagnet. Establish a model of the control circuit of the contactor; as well as Based on the models of the electromagnet and the control circuit, the gravity component is adjusted through simulation to obtain the contactor coil pull-in current under different gravity components.

5. The control method as described in claim 2, further comprising the step of determining the correspondence between the maintaining electromagnetic force and the maintaining current, including: Multiple holding currents are obtained for contactor coils with multiple different holding electromagnetic forces; The correspondence between the sustaining electromagnetic force and the sustaining current is determined based on the different sustaining electromagnetic forces and the plurality of sustaining currents.

6. The control method of claim 5, wherein acquiring multiple sustaining currents of the contactor coil for multiple different sustaining electromagnetic forces includes: Based on the structure of the electromagnet of the contactor, a model of the electromagnet is established, and material property parameters are assigned to the model of the electromagnet. Establish a model of the control circuit of the contactor; as well as Based on the models of the electromagnet and the control circuit, the holding electromagnetic force is adjusted through simulation to obtain the holding current of the contactor coil under different holding electromagnetic forces.

7. The control method as described in claim 3, wherein The multiple different gravity components are obtained by using different contactor installation angles.

8. The control method as described in claim 3, further comprising: The correspondence between the pull-in starting current and the gravitational component of the resistance system is supplemented by interpolation.

9. The control method as described in claim 5, further comprising: The correspondence between the sustaining electromagnetic force and the sustaining current is supplemented by interpolation.

10. The control method according to any one of claims 1 to 9, further comprising: The control voltage is pulse-width modulated to adjust the current in the contactor coil to a predetermined sustaining current.

11. The control method according to any one of claims 1-9, further comprising: Detect the holding current of the contactor coil; as well as When the sustaining current of the contactor coil is detected to exceed a predetermined threshold, the control voltage is pulse-width modulated to increase the current flowing through the contactor coil.

12. A contactor, comprising: The current acquisition unit is used to acquire the pull-in current of the contactor coil under the control voltage; as well as The processing unit is configured as follows: Determine the pull-in start current based on the obtained pull-in current; Based on the correspondence between the pull-in starting current and the gravitational component of the resistance system, the gravitational component is determined according to the pull-in starting current, wherein the resistance system is the sum of the resistances experienced by the contactor coil during pull-in maintenance, and the gravitational component is associated with the installation orientation of the contactor. The correspondence is obtained through simulation or testing. as well as The holding current of the contactor is determined based on the gravity component and the spring resistance of the resistance system.

13. The contactor of claim 12, wherein the processing unit is configured to determine the holding current of the contactor based on the gravity component and the spring resistance of the resistance system, comprising: The total resistance of the resistance system is determined based on the gravity component and the spring resistance of the resistance system. The holding electromagnetic force of the contactor is determined to be the total resistance plus a predetermined margin. as well as Based on the correspondence between the sustaining electromagnetic force and the sustaining current, the sustaining current is determined according to the sustaining electromagnetic force.

14. The contactor as claimed in claim 12 or 13, wherein The processing unit is configured as follows: The control voltage is pulse-width modulated to adjust the current in the contactor coil to a predetermined sustaining current.

15. The contactor as claimed in claim 12 or 13, wherein The processing unit is configured as follows: Detect the holding current of the contactor coil; When the sustaining current of the contactor coil is detected to exceed a predetermined threshold, the control voltage is pulse-width modulated to increase the current flowing through the contactor coil.

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