Variable frequency controller and control system

Abstract

The utility model discloses a frequency conversion controller and a control system, and the frequency conversion controller is characterized in that the frequency conversion controller comprises a power input interface which is used for receiving AC power supply; the rectification module is connected with the power supply input interface and is used for rectification; the current limiting module is located between the rectifier module and the first capacitor; the relay module is located between the rectifier module and the first capacitor; the first capacitor is located between the current limiting module and the driving module and supplies power to the driving module; the driving module drives a load through an output interface; the control module is connected with the driving module and controls the driving module; the control module is also connected with the relay module to control the on and off of the relay module; the capacitor interface is connected with the first capacitor; and the second capacitor is connected with the variable frequency controller through the capacitor interface. The second capacitor is externally hung on the capacitor interface, so that the adaptive capacity of the variable-frequency controller to low input voltage and under the working condition of violent fluctuation of the input voltage is remarkably enhanced, and the application range of the variable-frequency controller is expanded.

Description

Technical Field

[0001] The utility model relates to the technical field of frequency conversion control, and more specifically, to a frequency conversion controller and a control system. Background Art

[0002] With the promotion of energy conservation and emission reduction and the development of domestic agriculture, many remote barren mountains and lands have been transformed into agricultural land such as orchards and woodlands. In the water shortage season, artificial irrigation is required. The rapidly developing permanent magnet high-speed energy-saving deep well water pump in China has the advantages of high speed, small size and light weight. It is particularly suitable for extracting groundwater for irrigation in orchards during the dry season. However, the use of high-speed deep well water pumps usually requires a frequency conversion controller. Since orchards, woodlands, etc. are located in remote areas in the wild, some areas have poor power supply conditions, unstable voltage and frequent power outages. Sometimes generators are needed to generate electricity, and the generators matched by farmers are often not high in power, resulting in violent fluctuations in the power supply voltage provided to the frequency conversion controller. The existing film capacitor type frequency conversion controller cannot adapt to such harsh working conditions.

[0003] In order to enable the equipment to operate stably, it is urgent to design a frequency conversion controller and a corresponding control system to meet the needs under the above-mentioned conditions of severe power supply voltage fluctuations. Utility Model Content

[0004] The utility model aims to provide a frequency conversion controller and a control system to solve the existing technical problems and meet the requirements under the conditions of low input voltage and severe input voltage fluctuation.

[0005] According to one aspect of the utility model, a frequency conversion controller is provided, comprising: a power input interface, connected to a power supply, receiving a DC power supply or an AC power supply; a rectifier module, connected to the power input interface, rectifying the electrical signal of the power input interface; a current limiting module, connected between the rectifier module and a first capacitor, limiting the magnitude of the current; a relay module, connected between the rectifier module and the first capacitor; a first capacitor, connected between the current limiting module and a drive module, supplying power to the drive module; a drive module, driving a load via an output interface; a control module, connected to the drive module, controlling the drive module; the control module is also connected to the relay module, controlling the on and off of the relay module; the output interface, connected to the drive module, for connecting a load; a capacitor interface, connected to the first capacitor; wherein a second capacitor is connected to the frequency conversion controller via the capacitor interface.

[0006] Optionally, the frequency conversion controller includes a first circuit board and a first box body, and the first circuit board is sealed in the first box body.

[0007] Optionally, the power input interface, the rectifier module, the current limiting module, the relay module, the first capacitor, the drive module, the control module and the output interface are all located on a first circuit board.

[0008] Optionally, the first circuit board includes a plurality of wiring positions, and the plurality of wiring positions include a ground wiring position, a power input interface, a capacitor interface, and an output interface.

[0009] Optionally, the power input interface includes a three-phase AC input wiring position, the capacitor interface includes a capacitor positive wiring position and a capacitor negative wiring position, and the output interface includes a three-phase output wiring position.

[0010] Optionally, each of the plurality of wiring positions is provided with a corresponding waterproof interface, the first box body is provided with a sealing ring, and the waterproof grade of the first box body is not lower than IP54.

[0011] Optionally, the first capacitor is a film capacitor, and the second capacitor is an electrolytic capacitor.

[0012] Optionally, the relay module includes a controllable switch and a relay coil, the control module controls the on and off of the controllable switch by controlling whether the relay coil is energized, the controllable switch is connected in parallel with the current limiting module, and the controllable switch short-circuits the current limiting module when it is turned on.

[0013] According to another aspect of the utility model, a control system is also provided, including the above-mentioned frequency conversion controller and voltage stabilizer, the voltage stabilizer including: a second capacitor, the second capacitor is connected to a wire, the wire is connected to the capacitor interface, the second capacitor is connected in parallel with the first capacitor; the voltage stabilizer is connected to the capacitor interface of the frequency conversion controller via the wire.

[0014] Optionally, the frequency conversion controller includes a first circuit board and a first box body, and the first circuit board is sealed in the first box body; the voltage stabilizer includes a second circuit board and a second box body, and the second circuit board is sealed in the second box body.

[0015] Optionally, the power input interface, the rectifier module, the current limiting module, the relay module, the first capacitor, the drive module, the control module and the output interface are all located on a first circuit board, the second capacitor is located on a second circuit board, and the second circuit board is connected to the capacitor interface of the first circuit board through the wire to connect the second capacitor to the first capacitor.

[0016] In the above control system, the second box body is connected to the first box body in a pluggable manner.

[0017] Optionally, the first circuit board includes a plurality of wiring positions, and the plurality of wiring positions include a ground wiring position, a power input interface, a capacitor interface, and an output interface.

[0018] Optionally, the power input interface includes a three-phase AC input wiring position, the capacitor interface includes a capacitor positive wiring position and a capacitor negative wiring position, and the output interface includes a three-phase output wiring position.

[0019] Optionally, each of the plurality of wiring positions is provided with a corresponding waterproof interface, the first box body and the second box body are provided with a sealing ring, and the waterproof level of the first box body and the second box body is not lower than IP54.

[0020] Optionally, the first capacitor is a film capacitor, and the second capacitor is an electrolytic capacitor.

[0021] In the above-mentioned control system, the relay module includes a controllable switch and a relay coil. The control module controls the on and off of the controllable switch by controlling whether the relay coil is energized. The controllable switch is connected in parallel with the current limiting module. When the controllable switch is turned on, the current limiting module is short-circuited.

[0022] The frequency conversion controller and control system provided by the utility model realize an external second capacitor by setting a capacitor interface without changing the first capacitor in the frequency conversion controller, thereby significantly enhancing the adaptability of the frequency conversion controller and the corresponding control system to low input voltage and input voltage drastic fluctuation conditions, and expanding the application scope of the frequency conversion controller and the control system. At the same time, due to the use of the external second capacitor, the second capacitor is separated from the high heating environment of the first box body, which is conducive to extending the working life of the second capacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings.

[0024] Figure 1 A schematic diagram of a control system module of an embodiment of the utility model is shown;

[0025] Figure 2 An exploded schematic diagram of a first box body and a second box body of a control system according to an embodiment of the utility model is shown;

[0026] Figure 3 It shows an exploded schematic diagram of a control system according to an embodiment of the utility model after the first box body and the second box body are connected;

[0027] Figure 4 The overall schematic diagram of the control system of the embodiment of the utility model is shown. DETAILED DESCRIPTION

[0028] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, the same elements are represented by similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale. In addition, some well-known parts may not be shown.

[0029] It should be understood that when describing a structure, when a component or a module is said to be located "before" another component or another module, it may mean that it is directly located at the front end of the circuit of the other component or another module and connected to it, or that other components or modules are included between it and the other component or another module. In addition, if some modules are used, their positions and adjacency relationships can be adjusted as needed.

[0030] If it is intended to describe a situation where a component or module is directly located before another component or module, this document will use the expression “directly before” or “before and adjacent to”.

[0031] Many specific details of some embodiments of the present invention are described below, such as the specific circuit composition of the module, the component model, quantity and connection relationship, so as to more clearly understand the present invention. However, as those skilled in the art can understand, the present invention can be implemented without following these specific details.

[0032] The present invention may be embodied in various forms, some examples of which will be described below.

[0033] Figure 1 The module schematic diagram of the control system of the embodiment of the utility model is shown; the control system includes a first circuit board 110 and a second circuit board 120, the two circuit boards correspond to the variable frequency controller and the voltage stabilizer respectively, the power supply 200 of the variable frequency controller is, for example, a three-phase AC power supply, including R, S, T three-phase power supply; the load of the variable frequency controller is, for example, a motor 300. The first circuit board 110 is, for example, located in the first box body, and the second circuit board 120 is, for example, located in the second box body. Among them, the first circuit board 110 includes a power input interface 111, a rectifier module 112, a current limiting module 113, a first capacitor 114, a capacitor interface 115, a relay module 116, a control module 117, a drive module 118 and an output interface 119; the second circuit board 120 includes a second capacitor 121, and the positive electrode P+ and the negative electrode N- of the second capacitor 121 on the second circuit board 120 are respectively connected to the capacitor interface 115 of the first circuit board 110 through wires, so that the positive electrode P+ and the negative electrode N- of the first capacitor 114 are respectively connected to the positive electrode P+ and the negative electrode N- of the second capacitor 121, so as to realize the parallel connection of the second capacitor 121 and the first capacitor 114. Furthermore, the negative electrode of the capacitor interface 115 is also connected to the rectifier module 112. The first capacitor 114 is, for example, a thin film capacitor, and the second capacitor 121 is, for example, an electrolytic capacitor.

[0034] Specifically, in the first circuit board 110, the power input interface 111 is connected to the rectifier module 112, and the output of the rectifier module 112 is divided into two branches, one of which is connected to the current limiting module 113, and the other is connected to the relay module 116. The current limiting module 113 and the relay module 116 are both connected to the first capacitor 114. The first capacitor 114 is connected in parallel with the second capacitor 121 and the first capacitor 114 is connected to the drive module 118 to provide power for the drive module 118. The control module 117 is connected to the relay module 116 and the drive module 118. The control module 117 is used to control the relay module 116 and the drive module 118. The drive module 118 is connected to the output interface 119, which is, for example, a three-phase output interface, including three phases U, V, and W, which are respectively connected to each phase of the motor 300. Furthermore, the relay module 116 includes a controllable switch for controlling the on and off of the busbar, and a relay coil. The control module 117 can control the on and off of the controllable switch by controlling whether the relay coil is energized, thereby connecting or disconnecting the busbar.

[0035] The power supply 200 is connected to the rectifier module 112 inside the frequency conversion controller through the power input interface 111. The power supply 200 provides alternating current, for example. The alternating current passes through the rectifier module 112 to output direct current, and the direct current passes through the current limiting module 113 or the relay module 116 to supply power to the first capacitor 114 and the driving module 118.

[0036] The operation of the frequency conversion controller includes: in the initial state, the first capacitor 114 is not fully charged, the control module 117 controls the controllable switch in the relay module 116 to be disconnected, the direct current after passing through the rectifier module 112 is limited by the current limiting module 113, and a small current is charged to the first capacitor 114 until it is fully charged;

[0037] When the first capacitor 114 is fully charged, the control module 117 controls the controllable switch in the relay module 116 to close. Since the relay module 116 is connected in parallel with the current limiting module 113, the current limiting module 113 is short-circuited, and the DC power is supplied to the first capacitor 114 and the driving module 118 through the controllable switch in the relay module 116. Since the current on the line is not limited, the current increases compared to when passing through the current limiting module 113, and the driving ability of the motor 300 is improved. The driving module 118 drives the motor to work via the output interface 119.

[0038] Figure 2 and Figure 3 The exploded schematic diagram of the first box body and the second box body of the frequency conversion controller according to the utility model embodiment and the exploded schematic diagram after being connected are respectively shown; Figure 2 and Figure 3It can be seen that the first box body includes a first box body upper cover 1 and a first box body lower shell 7. The first circuit board 110 in the first box body is provided with a terminal 2 on one side thereof. The terminal 2 includes, for example, a plurality of wiring positions. Specifically, the plurality of wiring positions include, from left to right, a ground wiring position, a power input interface (three-phase alternating current R, S, T input wiring position), a capacitor interface (capacitor positive wiring position and capacitor negative wiring position), and an output interface (three-phase output U, V, W wiring position); the first box body lower shell 7 is provided with waterproof interfaces 3, 4, and 5, wherein the waterproof interface 3 corresponds to, for example, the ground wiring position and the power input interface, the waterproof interface 4 corresponds to, for example, the capacitor interface, the waterproof interface 5 corresponds to, for example, the output interface, and the interface 6 is, for example, other auxiliary interfaces. The external wires (for example, the capacitor positive lead 9 and the capacitor negative lead 8) pass through the corresponding waterproof interfaces and enter the first box body, and are fixedly connected to the terminal 2 by the screws on the terminal 2 and realize the corresponding electrical connection. The second box body includes a second box body upper cover 12 and a second box body lower shell 10. One end of the capacitor negative lead 8 and the capacitor positive lead 9 are, for example, welded through the waterproof interface of the second box body and connected to the second circuit board 120. The other end of the capacitor negative lead 8 and the capacitor positive lead 9 are connected to the capacitor interface through the waterproof interface 4 of the first box body. Specifically, the capacitor negative lead 8 and the capacitor positive lead 9 are provided with a connection terminal at one end connected to the capacitor interface. The connection terminal is, for example, a nickel sheet. When the waterproof interface 4 is loosened, the wire with the nickel sheet passes through the waterproof interface 4, and the nickel sheet is plugged into the wiring position of the capacitor interface of the first circuit board 110 to realize the connection between the second capacitor and the first capacitor.

[0039] The wire for inputting the power supply is a wire including three R, S, and T phase wires. When the waterproof interface 3 is loosened, the wire passes through the waterproof interface 3 and is welded to the R, S, and T input wiring positions of the power input interface. The wire for output connected to the load is, for example, a wire including three U, V, and W phase wires. When the waterproof interface 5 is loosened, the wire passes through the waterproof interface 5 and is welded to the U, V, and W output wiring positions of the output interface. After the connection is completed, the waterproof interfaces 3, 4, and 5 are tightened to seal.

[0040] The second circuit board 120 is provided with a second capacitor, which is aligned with the mounting post of the second box body lower shell 10 through a positioning hole and connected and fixed by screws, and the second capacitor in the second box body is connected in parallel with the first capacitor in the first box body through the capacitor negative lead 8 and the capacitor positive lead 9. Of course, the second capacitor may not be sealed in the second box body.

[0041] Figure 4The overall schematic diagram of the frequency conversion controller of the embodiment of the utility model is shown. The first box body and the second box body respectively seal the first circuit board 110 and the second circuit board 120 therein. Specifically, the first box body and the second box body are both waterproof, and a sealing ring is provided between the upper cover and the lower shell for sealing, and each interface is a waterproof interface, so that the first box body and the second box body meet the waterproof requirements of IP54 to meet the harsh working conditions such as deep wells.

[0042] The frequency conversion controller and control system provided by the utility model realize an external second capacitor by setting a capacitor interface without changing the first capacitor in the frequency conversion controller, thereby significantly enhancing the adaptability of the frequency conversion controller and the corresponding control system to low input voltage and input voltage drastic fluctuation conditions, and expanding the application scope of the frequency conversion controller and the control system. At the same time, due to the use of the external second capacitor, the second capacitor is separated from the high heating environment of the first box body, which is conducive to extending the working life of the second capacitor.

[0043] In the above description, the technical details such as the position combination and connection mode of each component are not described in detail. However, those skilled in the art should understand that various technical means can be used to form the required connection relationship, etc. In addition, in order to have the same function, those skilled in the art can also design a structure that is not completely the same as the structure described above. In addition, although each embodiment is described above separately, this does not mean that the measures in each embodiment cannot be used in combination to advantage.

[0044] The embodiments of the present invention are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, a person skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A frequency conversion controller, characterized in that: include: A power input interface, connected to a power supply, to receive DC power or AC power; A rectifier module, connected to the power input interface, for rectifying the electrical signal of the power input interface; A current limiting module, connected between the rectifier module and the first capacitor, to limit the current; A relay module is connected between the rectifier module and the first capacitor; A first capacitor is connected between the current limiting module and the driving module to supply power to the driving module; A driving module drives a load via an output interface; A control module connected to the driving module, the control module controls the driving module; the control module is also connected to the relay module, the control module controls the on and off of the relay module; The output interface is connected to the driving module and is used to connect to a load; A capacitor interface connected to the first capacitor; Wherein, the second capacitor is connected to the frequency conversion controller through the capacitor interface.

2. The frequency conversion controller according to claim 1, characterized in that: The frequency conversion controller comprises a first circuit board and a first box body, wherein the first circuit board is sealed in the first box body.

3. The frequency conversion controller according to claim 2, characterized in that: The power input interface, the rectifier module, the current limiting module, the relay module, the first capacitor, the drive module, the control module and the output interface are all located on a first circuit board.

4. The frequency conversion controller according to claim 2, characterized in that: The first circuit board includes a plurality of wiring positions, and the plurality of wiring positions include a ground wiring position, a power input interface, a capacitor interface, and an output interface.

5. The frequency conversion controller according to claim 4, characterized in that: The power input interface includes a three-phase AC input wiring position, the capacitor interface includes a capacitor positive electrode wiring position and a capacitor negative electrode wiring position, and the output interface includes a three-phase output wiring position.

6. The frequency conversion controller according to claim 5, characterized in that: The plurality of wiring positions are each provided with a corresponding waterproof interface, the first box body is provided with a sealing ring, and the waterproof grade of the first box body is not lower than IP54.

7. The frequency conversion controller according to claim 1, characterized in that: The first capacitor is a film capacitor, and the second capacitor is an electrolytic capacitor.

8. The frequency conversion controller according to claim 1, characterized in that: The relay module includes a controllable switch and a relay coil. The control module controls the on and off of the controllable switch by controlling whether the relay coil is energized. The controllable switch is connected in parallel with the current limiting module. When the controllable switch is turned on, the current limiting module is short-circuited.

9. A control system, characterized in that: It includes a frequency conversion controller and a voltage stabilizer as described in any one of claims 1 to 8, wherein the voltage stabilizer includes: a second capacitor, the second capacitor is connected to a wire, the wire is connected to the capacitor interface, and the second capacitor is connected in parallel with the first capacitor; the voltage stabilizer is connected to the capacitor interface of the frequency conversion controller via the wire.

10. The control system according to claim 9, characterized in that: The frequency conversion controller comprises a first circuit board and a first box body, wherein the first circuit board is sealed in the first box body; the voltage stabilizer comprises a second circuit board and a second box body, wherein the second circuit board is sealed in the second box body.

11. The control system according to claim 10, characterized in that: The power input interface, the rectifier module, the current limiting module, the relay module, the first capacitor, the drive module, the control module and the output interface are all located on a first circuit board, the second capacitor is located on a second circuit board, and the second circuit board is connected to the capacitor interface of the first circuit board through the wire to connect the second capacitor to the first capacitor.

12. The control system according to claim 10, characterized in that: The second box body is connected to the first box body in a pluggable manner.

13. The control system according to claim 10, characterized in that: The first circuit board includes a plurality of wiring positions, and the plurality of wiring positions include a ground wiring position, a power input interface, a capacitor interface, and an output interface.

14. The control system according to claim 13, characterized in that: The power input interface includes a three-phase AC input wiring position, the capacitor interface includes a capacitor positive electrode wiring position and a capacitor negative electrode wiring position, and the output interface includes a three-phase output wiring position.

15. The control system according to claim 13, characterized in that: The plurality of wiring positions are each provided with a corresponding waterproof interface, the first box body and the second box body are both provided with a sealing ring, and the waterproof level of the first box body and the second box body is not lower than IP54.

16. The control system according to claim 9, characterized in that: The first capacitor is a film capacitor, and the second capacitor is an electrolytic capacitor.

17. The control system according to claim 9, characterized in that: The relay module includes a controllable switch and a relay coil. The control module controls the on and off of the controllable switch by controlling whether the relay coil is energized. The controllable switch is connected in parallel with the current limiting module. When the controllable switch is turned on, the current limiting module is short-circuited.

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