CN117174511B - State light reporting device and method for bypass switch of flexible direct-current transmission power module - Google Patents

Abstract

A state light return device and method of a bypass switch of a flexible direct current transmission power module comprises a body, wherein a slot is formed in the body, a baffle is arranged on the body, the baffle is connected with a movable mechanism of the bypass switch, and the baffle can move along the slot of the body under the drive of the movable mechanism; holes communicated with the grooves are formed in the two sides of the grooves on the body and used for installing optical cables, and optical signal passing holes are formed in the baffle plate; when the bypass switch is in an on state, the baffle moves until the optical signal passing holes are aligned with the optical cables on the two sides, and when the bypass switch is in an off state, the baffle moves until the optical signal passing holes are staggered with the optical cables on the two sides; the fiber optic cable is connected to the PMC board. The invention directly transmits the optical signal without photoelectric conversion, can completely immunity the interference of electromagnetic field, changes the state of the optical signal according to the state of the bypass switch, and does not cause signal oscillation when the state is changed, so that the optical signal directly returns to the PMC board in different forms, and the reported state of the bypass switch is ensured to be accurate.

Description

Status light reporting device and method for flexible DC transmission power module bypass switch

Technical field

The invention belongs to the technical field of flexible direct current transmission, and specifically relates to a status light reporting device and method for a bypass switch of a flexible direct current transmission power module.

Background technique

In the flexible DC transmission system, each power module is equipped with a bypass switch. When the module voltage or current status is abnormal, the power module control board (PMC board) will send a bypass command to the bypass switch. The switch will quickly turn off and short-circuit the internal sub-module to prevent the fault from spreading to the entire system. At the same time, the status of the bypass switch must be accurately sent to the PMC board, otherwise the PMC board will judge that the bypass switch refuses to move, causing the system to trip.

The original bypass switch integrates a detection circuit on the drive circuit. The detection circuit generates an electrical signal, which is connected to the micro switch inside the bypass switch through a wire and then returns to the detection circuit. When the bypass switch acts, the micro switch acts to interrupt the electrical signal, and the detection circuit generates an optical signal based on the state of the electrical signal and sends it to the PMC board.

When the micro switch operates, it is necessary to use a spring to separate the internal copper sheets. During the spring separation process, the copper sheets will inevitably bounce, causing oscillation of the electrical signal, which can easily cause abnormal signal recognition. Moreover, extremely high voltages and currents are applied to the power module, and the electromagnetic environment is extremely complex. Electrical signals are easily affected by the electromagnetic environment, causing changes in electrical signals. Once the electrical signal is wrong and the PMC board thinks that the bypass switch refuses to move, it will cause the system to trip, affecting the operation of the entire converter valve and causing great economic losses. At the same time, the electrical signal needs to be converted into an optical signal before it can be sent to the PMC board, which requires a separate circuit to implement, which not only increases the cost of the module, but also increases the failure rate of the module.

Related existing technologies, such as the patent application with publication number CN105548871A, which discloses "an MMC sub-module bypass switch status detection device and MMC sub-module bypass switch", also have the following shortcomings: 1) The switch status signal is an electrical signal, There are hidden dangers of being affected by the electromagnetic environment. 2) The change of the electrical signal depends on the micro switch inside the switch, and the signal will oscillate when it operates. 3) The signals of the entire device and the control panel are also electrical signals, which may be affected by the electromagnetic environment. 4) If this device is used, the overall structure of the module must be redesigned according to this device, and the original bypass switch cannot be directly replaced.

Contents of the invention

The purpose of the present invention is to provide a status light reporting device and method for the bypass switch of a flexible DC power module in order to solve the above-mentioned problems in the prior art that the status signal of the bypass switch is complex and susceptible to interference. According to the status change of the bypass switch, The state of the optical signal, and when the state changes, it will not cause signal oscillation, so that the optical signal directly returns to the PMC board in different forms, informing the PMC board of the status of the bypass switch at this time, while avoiding additional photoelectric conversion circuits and anti-electromagnetic compatibility circuits the design of.

In order to achieve the above objects, the present invention has the following technical solutions:

In the first aspect, a status light reporting device for a bypass switch of a flexible DC power module is provided, which includes a body, a slot is provided on the body, and a baffle is installed in the slot. The baffle is connected to the movable mechanism of the bypass switch. The baffle Driven by the movable mechanism, it can move along the groove of the body; the body is provided with holes connected to the groove on both sides of the groove, the holes are used to install optical cables, and the baffle is provided with optical signal passage holes; when bypassing When the switch is in the open state, the baffle moves to the position where the optical signal through hole is aligned with the optical cables on both sides. When the bypass switch is in the off state, the baffle moves to the position where the optical signal through hole is misaligned with the optical cables on both sides; the optical cable and PMC board connection.

As a preferred solution, a plurality of light signal passage holes are spaced on the baffle, and multiple pairs of holes connected to the groove are provided on both sides of the groove corresponding to each light signal passage hole on the baffle for installing multiple light signal passage holes. When the bypass switch is in the open state, the baffle moves to the position where each optical signal through hole is aligned with the corresponding optical cable on both sides. When the bypass switch is in the off state, the baffle moves to the position where each optical signal passes through the hole. The through holes are misaligned with the corresponding optical cables on both sides.

As a preferred solution, the baffle is also provided with a strip hole, and the body opens a hole between the two side walls of the groove and installs a positioning bolt. The positioning bolt passes through the strip hole of the baffle, and the strip hole Used to limit the range of movement of the baffle.

As a preferred solution, a spring is installed inside the groove of the body, and the spring support is provided at the bottom end of the baffle.

As a preferred solution, the body is arranged inside the bypass switch and is connected to the bypass switch through mounting bolts. The baffle is connected to the movable mechanism of the bypass switch using bolts.

As a preferred solution, the optical cable head of the optical cable uses an MF end. The MF end can be tightly installed in the hole opened on the body. After installation, the distance between the end faces of the optical cables on both sides is ≤5mm.

As a preferred solution, the optical cable uses a POF optical cable, and the core diameter of the POF optical cable is 1 mm.

In the second aspect, a state light reporting method for a bypass switch of a flexible DC power module is provided, including:

A baffle with a hole for optical signal passage is provided between the two optical cables;

Connect the optical cable to the PMC board, and connect the baffle to the movable mechanism of the bypass switch;

When the bypass switch is in the open state, the movable mechanism drives the baffle to move to the position where the optical signal passage hole is aligned with the optical cables on both sides. The optical signal passes through the optical signal passage hole of the baffle, connecting the two optical cables;

When the bypass switch is in the off state, the movable mechanism drives the baffle to move to a position where the optical signal passage hole is misaligned with the optical cables on both sides. The optical signal cannot pass through the optical signal passage hole of the baffle, and there is no signal input to the PMC board.

As a preferred solution, the moving direction of the baffle is kept perpendicular to the arrangement direction of the two optical cables.

As a preferred solution, a plurality of optical signal passage holes are provided at intervals on the baffle, and multiple sets of optical cables are provided on both sides of the baffle corresponding to each optical signal passage hole; when the bypass switch is in the open state, The movable mechanism drives the baffle to move until each optical signal through hole is aligned with the corresponding optical cables on both sides. When the bypass switch is in the off state, the movable mechanism drives the baffle to move until each optical signal through hole is aligned with the corresponding two optical cables. The side optical cable is misplaced.

Compared with the prior art, the present invention at least has the following beneficial effects:

The status light reporting device of the bypass switch of the flexible DC power module of the present invention directly transmits optical signals without the need for photoelectric conversion. It can be completely immune to any interference from electromagnetic fields and ensure that the reported status of the bypass switch is accurate. The baffle is hard-connected to the movable mechanism of the bypass switch. The movable mechanism directly drives the movement of the baffle. It can change its internal light path according to the movable mechanism of the bypass switch to change the opening and closing of the optical signal without causing signal oscillation. Or there is a delay between the switching action and the status signal. The device of the invention is small in size, light in weight, and is a purely mechanical mechanism that does not require power supply. It can directly replace the micro switch in the original bypass switch without redesigning or purchasing the entire bypass switch, and will not affect the performance of the power module. Structure and weight. The invention can directly control the optical signal and return it to the PMC board without using a circuit board to convert the electrical signal into an optical signal and then return it to the PMC board, thereby reducing the module cost and failure rate.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings needed to describe the embodiments. Obviously, the following drawings are only some of the drawings of the embodiments of the present invention. Those of ordinary skill in the art can also obtain drawings of other embodiments based on these drawings without exerting any creative effort.

Figure 1 is a structural front view of a status light reporting device according to an embodiment of the present invention.

Figure 2 is a structural cross-sectional view of a status light reporting device according to an embodiment of the present invention.

Figure 3 is a schematic assembly diagram of the status light reporting device according to the embodiment of the present invention when the bypass switch is turned on.

Figure 4 is a schematic assembly diagram of the status light reporting device according to the embodiment of the present invention when the bypass switch is turned off.

Figure 5 is a schematic cross-sectional view of the device with the bypass switch turned on during normal operation of the system according to the embodiment of the present invention.

Figure 6 is a schematic diagram of the circuit in the open state of the bypass switch during normal operation of the system according to the embodiment of the present invention.

Figure 7 is a schematic cross-sectional view of the device in the off state of the bypass switch when the system of the embodiment of the present invention is operating abnormally.

Figure 8 is a schematic diagram of the circuit in the off state of the bypass switch when the system of the embodiment of the present invention is operating abnormally.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention.

Please refer to Figures 1 and 2. The status light reporting device of the bypass switch of the flexible DC power module according to the embodiment of the present invention includes a body 1. The body 1 has a slot and is installed with a baffle 2. The body 1 is provided with openings on both sides of the slot. The hole connected with the slot is used to install the optical cable 3. The baffle 2 is provided with an optical signal passage hole, and the optical cable 3 is connected to the PMC board.

As shown in Figures 3 and 4, the body 1 of the embodiment of the present invention is arranged inside the bypass switch 21 and is connected to the bypass switch 21 through the mounting bolts 24. The baffle 2 is connected to the movable mechanism 22 of the bypass switch 21. Connected with bolts. The baffle 2 can move along the groove of the body 1 driven by the movable mechanism 22 . The baffle 2 is also provided with a strip hole. The body 1 has a hole between the two side walls of the groove and installs a positioning bolt 5. The positioning bolt 5 passes through the strip hole of the baffle 2. The strip hole defines the baffle. 2 range of activities. A spring 4 is installed inside the groove of the body 1, and the spring 4 is supported on the bottom end of the baffle 2.

In one possible implementation, the baffle 2 is provided with two optical signal passage holes at intervals, and the body 1 is provided with two pairs of holes connected to the groove on both sides of the groove corresponding to each optical signal passage hole for installation. For multiple sets of optical cables 3, when the bypass switch 21 is in the open state, the baffle 2 moves to a position where each optical signal passage hole is aligned with the corresponding optical cable 3 on both sides. When the bypass switch 21 is in the off state, the baffle 2 2. Move until each optical signal passage hole is misaligned with the corresponding optical cable 3 on both sides.

As shown in Figure 5, when the system is operating normally according to the embodiment of the present invention, the bypass switch 21 is in the open state, and the baffle 2 moves to a position where the optical signal passage holes are aligned with the optical cables 3 on both sides. The circuit structure is shown in Figure 6 .

As shown in Figure 7, when the system operates abnormally according to the embodiment of the present invention, the bypass switch 21 is in the off state, and the baffle 2 moves to a position where the optical signal passage hole is misaligned with the optical cables 3 on both sides. The circuit structure is shown in Figure 8 .

In one possible implementation, the optical cable head of the optical cable 3 uses an MF end. The MF end can be tightly installed in the hole opened on the body 1. After installation, the distance between the end faces of the optical cables 3 on both sides is ≤5mm.

In one possible implementation, the optical cable 3 uses a POF optical cable. The core diameter of the POF optical cable is 1 mm, which can ensure that when the distance between the optical cable heads on both sides is ≤ 5 mm, the optical signal will not be lost due to scattering.

Another embodiment of the present invention provides a status light reporting method for a bypass switch of a flexible DC power module, including:

A baffle 2 with an optical signal passage hole is provided between the two optical cables 3;

Connect the optical cable 3 to the PMC board, and connect the baffle 2 to the movable mechanism 22 of the bypass switch 21;

When the bypass switch 21 is in the open state, the movable mechanism 22 drives the baffle 2 to move to a position where the optical signal passage holes are aligned with the optical cables 3 on both sides. The optical signal passes through the optical signal passage holes of the baffle 2, and the two optical cables are 3 connected;

When the bypass switch 21 is in the off state, the movable mechanism 22 drives the baffle 2 to move to a position where the optical signal passing hole is misaligned with the optical cables 3 on both sides. The optical signal cannot pass through the optical signal passing hole of the baffle 2, and the PMC board has no signal input.

In a possible implementation, the moving direction of the baffle 2 is kept perpendicular to the arrangement direction of the two optical cables 3 .

In one possible implementation, a plurality of optical signal passage holes are provided at intervals on the baffle 2 , and multiple sets of optical cables 3 are provided on both sides of the baffle 2 corresponding to each optical signal passage hole. When the bypass switch 21 When the bypass switch 21 is in the off state, the movable mechanism 22 drives the baffle 2 to move until each optical signal passage hole is aligned with the corresponding optical cable 3 on both sides. Each optical signal passage hole is misaligned with the corresponding optical cables 3 on both sides.

As shown in Figure 5, when the bypass switch 21 is turned on and the power module operates normally, the movable mechanism 22 of the bypass switch 21 presses the baffle 2 into the body 1. The optical signal passage hole opened on the baffle 2 is just aligned with the optical cables 3 on both sides. At this time, the optical signal can pass through the optical signal passage hole, so that the optical signal is input to the PMC board from another optical cable 3. At this time, the PMC board will It is determined that the bypass switch 21 is in the open state.

As shown in Figure 7, when the bypass switch 21 is in the off state, the sub-module is cut off at this time. As shown in Figure 8, since the movable mechanism 22 of the bypass switch 21 pulls out the baffle 2, the opening on the baffle 2 The optical signal is displaced through the hole. At this time, the optical signal cannot be sent to the optical cable 3 at the other end through the baffle 2, and the optical signal cannot be input to the PMC board. At this time, the PMC board will judge that the bypass switch 21 is in an off state.

The spring 4 of the status light reporting device of the bypass switch of the flexible DC power module in the embodiment of the present invention serves as a limiting function, allowing the baffle 2 to always move perpendicular to the arrangement direction of the two optical cables 3, preventing the baffle 2 from tilting and interfering with the main body. 1 or optical cable 3 collides. The positioning bolt 5 plays a positioning function. It is inserted from the threaded hole on the body 1 and passes through the strip hole in the middle of the baffle 2, so that the end face of the baffle 2 is always perpendicular to the optical cable 3 and will not rotate internally, causing it to interfere with the optical cable 3. A collision occurs.

The front end of the baffle 2 is provided with a thread of a certain length, and the nut 23 can be used to connect the movable mechanism 22 of the bypass switch 21 with bolts. When the bypass switch 21 operates, the baffle 2 and the bypass switch 21 move synchronously to ensure the return of light. There is no delay between the signal and the action of bypass switch 21. At the same time, it can be ensured that the baffle 2 will not bounce during the pulling process, causing signal oscillation.

The status light reporting device of the bypass switch of the flexible DC transmission power module of the present invention has a purely mechanical structure, has high reliability and long life. This device can be used to transmit optical signals. The PMC board directly sends optical signals to the device. The device changes its internal optical path according to the status of the bypass switch, so that the optical signal returns directly to the PMC board in different forms, informing the PMC board of this state of the bypass switch while avoiding the design of additional photoelectric conversion circuits and anti-electromagnetic compatibility circuits.

The device according to the embodiment of the present invention can change the state of the optical signal according to the state of the bypass switch, and will not cause signal oscillation when the state changes. At the same time, the device has multiple optical channels, which can meet the cross-communication function of the flexible DC transmission power module.

In the embodiment of the present invention, the status light reporting device of the bypass switch of the flexible DC transmission power module is connected by an optical cable 3, which can directly transmit optical signals. According to the movable mechanism 22 of the bypass switch 21, it changes its internal optical path to change the opening and closing of the optical signal. The baffle 2 and the movable mechanism 22 are hard connected. The movable mechanism 22 directly drives the baffle 2 to move, rather than relying on the elastic force of the spring 4. Therefore, when the bypass switch 21 moves, the baffle 2 will not bounce due to The signal oscillates without causing a delay between the switching action and the status signal. Since the status signal is an optical signal, it can be completely immune to any interference from the electromagnetic field, ensuring that the reported switch status is accurate. The status light reporting device of the bypass switch of the flexible DC power module according to the embodiment of the present invention is small in size and light in weight. It can directly replace the micro switch in the original bypass switch 21 without redesigning or purchasing the entire bypass switch 21. It does not affect the structure and weight of the power module. It can directly control the optical signal and return it to the PMC board. There is no need to use a circuit board to convert the electrical signal into an optical signal and then return it to the PMC board, so the module cost and failure rate can be reduced. It also supports simultaneous transmission of multiple status signals to meet the cross-communication function of flexible DC transmission power modules.

The above-described embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still implement the above-mentioned implementations. The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions in the embodiments of this application, and should be included in within the protection scope of this application.

Claims (8)

1. The utility model provides a flexible direct current transmission power module bypass switch's state light repayment device which characterized in that: the device comprises a body (1), wherein a groove is formed in the body (1), a baffle (2) is arranged in the groove, the baffle (2) is connected with a movable mechanism (22) of a bypass switch (21), and the baffle (2) can move along the groove of the body (1) under the drive of the movable mechanism (22); holes communicated with the grooves are formed in the two sides of the grooves on the body (1), the holes are used for installing optical cables (3), and the baffle (2) is provided with optical signal passing holes; when the bypass switch (21) is in an on state, the baffle plate (2) moves to a position where the optical signal passing holes are aligned with the optical cables (3) on two sides, and when the bypass switch (21) is in an off state, the baffle plate (2) moves to a position where the optical signal passing holes are staggered with the optical cables (3) on two sides; the optical cable (3) is connected with the PMC plate; a plurality of optical signal passing holes are formed in the baffle plate (2) at intervals, a plurality of pairs of holes communicated with the grooves are formed in the two sides of the grooves corresponding to each optical signal passing hole in the body (1) and are used for installing a plurality of groups of optical cables (3); when the bypass switch (21) is in an on state, the baffle plate (2) moves to a position where each optical signal passing hole is aligned with the corresponding two-side optical cables (3), and when the bypass switch (21) is in an off state, the baffle plate (2) moves to a position where each optical signal passing hole is dislocated with the corresponding two-side optical cables (3); the baffle plate (2) is further provided with a strip-shaped hole, the body (1) is provided with holes between two side wall surfaces of the groove and is provided with positioning bolts (5), the positioning bolts (5) penetrate through the strip-shaped hole of the baffle plate (2), and the strip-shaped hole is used for limiting the movable range of the baffle plate (2).

2. The status light reporting device of claim 1 wherein the flexible dc power module bypass switch is configured to: a spring (4) is arranged in the groove of the body (1), and the spring (4) is supported and arranged at the bottom end of the baffle plate (2).

3. The status light reporting device of claim 1 wherein the flexible dc power module bypass switch is configured to: the body (1) is arranged in the bypass switch (21) and is connected with the bypass switch (21) through a mounting bolt (24), and the baffle (2) is connected with a movable mechanism (22) of the bypass switch (21) through a bolt.

4. The status light reporting device of claim 1 wherein the flexible dc power module bypass switch is configured to: the optical cable head of the optical cable (3) uses an MF end head, the MF end head can be tightly installed in a hole formed in the body (1), and the end face distance of the optical cables (3) on two sides after the installation is less than or equal to 5mm.

5. The status light reporting device of claim 4 wherein the flexible dc power module bypass switch is configured to: the optical cable (3) uses a POF optical cable, and the core diameter of the POF optical cable is 1mm.

6. A status light reporting method for a bypass switch of a flexible direct current transmission power module, which is characterized in that the status light reporting device based on the bypass switch of the flexible direct current transmission power module according to any one of claims 1 to 5 is realized, comprising:

a baffle plate (2) provided with an optical signal passing hole is arranged between the two optical cables (3);

connecting the optical cable (3) with the PMC plate, and connecting the baffle plate (2) with a movable mechanism (22) of a bypass switch (21);

when the bypass switch (21) is in an on state, the movable mechanism (22) drives the baffle plate (2) to move to a position where the optical signal passing holes are aligned with the optical cables (3) on two sides, and the optical signals penetrate through the optical signal passing holes of the baffle plate (2) to communicate the two optical cables (3);

when the bypass switch (21) is in an off state, the movable mechanism (22) drives the baffle plate (2) to move to a position where the optical signal passing holes are staggered with the optical cables (3) on two sides, and optical signals cannot penetrate through the optical signal passing holes of the baffle plate (2) and no signal is input to the PMC plate.

7. The status light reporting method of the bypass switch of the flexible direct current transmission power module according to claim 6, wherein the moving direction of the baffle plate (2) is kept perpendicular to the arrangement direction of the two optical cables (3).

8. The status light return method of the bypass switch of the flexible direct current transmission power module according to claim 6, characterized in that a plurality of light signal passing holes are formed on the baffle plate (2) at intervals, and a plurality of groups of optical cables (3) are arranged on two sides of the baffle plate (2) corresponding to each light signal passing hole; when the bypass switch (21) is in an on state, the movable mechanism (22) drives the baffle plate (2) to move until each optical signal passing hole is aligned with the corresponding two-side optical cables (3), and when the bypass switch (21) is in an off state, the movable mechanism (22) drives the baffle plate (2) to move until each optical signal passing hole is staggered with the corresponding two-side optical cables (3).