Marine dynamic advanced capacitive power compensation device and method

Abstract

The invention discloses a dynamic advanced capacitive power compensation device and method for a ship. The device comprises a capacitive power compensation starting module, a capacitive power compensation module, a load inductive reactance starting module and a power factor detection module, the capacitive power compensation module comprises an adjustable reactor, an adjustable control switch and a compensation capacitor unit; the load inductive reactance starting module is connected with the three-phase high-voltage bus and an external load inductive reactance module; the power factor detection module is arranged at the output end of the external load inductive reactance module; the power factor detection module is electrically connected with the adjustable control switch; the input end of the adjustable reactor is electrically connected with the three-phase high-voltage bus through the capacitive power compensation starting module; the output end of the adjustable reactor is electrically connected with the compensation capacitor unit in series; and the adjustable control switch is electrically connected with the control end of the adjustable reactor. According to the scheme, the starting torque of the load is ensured on the basis of reducing or eliminating the impact of starting on the power grid.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of power grid compensation, and in particular to a ship-based dynamic leading capacitive power compensation device and method. Background Art

[0002] At present, when starting large-load inductive devices (such as motors), ship power stations usually use reduced voltage starting or variable frequency starting to reduce the impact on the power grid. Commonly used reduced voltage starting methods include star-delta starting, auto-coupling reduced voltage starting and soft starter starting. These reduced voltage starting methods reduce the starting current, which will reduce the starting torque of large-load inductive devices, thereby reducing the ability of large-load inductive devices to start with load. In particular, variable frequency starting will also reduce the starting torque of the equipment due to the principle of variable frequency starting, thereby reducing the ability of the equipment to start with load. Summary of the invention

[0003] The present invention provides a marine dynamic leading capacitive power compensation device and method, so as to provide sufficient capacitive reactive power when a large inductive load is started, reduce the requirement for reactive power output of the power grid, reduce or eliminate the impact of starting on the power grid, and ensure the starting torque of the load at the same time.

[0004] To achieve the above objectives, in a first aspect, an embodiment of the present invention provides a marine dynamic leading capacitive power compensation device, the device comprising: a capacitive power compensation starting module, a capacitive power compensation module, a load inductive reactance module starting module and a power factor detection module; the capacitive power compensation module comprises an adjustable reactor, an adjustable control switch and a compensation capacitor unit;

[0005] The load inductive reactance starting module is connected to the three-phase high-voltage bus and the external load inductive reactance module; the power factor detection module is arranged at the output end of the external load inductive reactance module; the power factor detection module is electrically connected to the adjustable control switch;

[0006] The input end of the adjustable reactor is electrically connected to the three-phase high-voltage bus through the capacitive power compensation starting module; the output end of the adjustable reactor is electrically connected in series with the compensation capacitor unit; and the adjustable control switch is electrically connected to the control end of the adjustable reactor.

[0007] Optionally, the device further includes: a work start control module and a transformer; the first end of the primary coil of the transformer is connected to the A-phase high-voltage bus; the second end of the primary coil of the transformer is connected to the C-phase high-voltage bus; the first end of the secondary coil of the transformer is connected to the A-phase low-voltage bus; the second end of the secondary coil of the transformer is connected to the C-phase low-voltage bus;

[0008] The load inductive reactance module starting module includes a first starting switch and a first starting coil; the first starting switch is coupled to the first starting coil;

[0009] The A-phase low-voltage bus is connected to the first end of the first starting coil through the work start control module; the second end of the first starting coil is connected to the C-phase low-voltage bus; and the first starting switch is connected to the three-phase high-voltage bus.

[0010] Optionally, the capacitive power compensation starting module includes: a second starting switch, a second starting coil, a first delay coil and a first delay normally closed switch; the second starting switch is coupled to the second starting coil; the first delay coil and the first delay normally closed switch are coupled to each other;

[0011] The A-phase low-voltage bus is also connected to the first end of the first delay coil through the work start control module; the first end of the first delay coil is connected to the C-phase low-voltage bus;

[0012] The A-phase low-voltage bus is also connected to the first end of the first delayed normally closed switch through the working start control module; the second end of the first delayed normally closed switch is electrically connected to the first end of the second starting coil; the second end of the second starting coil is connected to the C-phase low-voltage bus; the second starting switch connects the three-phase high-voltage bus and the adjustable reactor.

[0013] Optionally, the compensation capacitor unit is an angular supplementary capacitor unit; the compensation capacitor unit includes a first capacitor, a second capacitor and a third capacitor; the adjustable reactor includes a first variable inductor, a second variable inductor and a third variable inductor;

[0014] The A-phase high-voltage bus is electrically connected to the first end of the first capacitor and the first end of the third capacitor through the first variable inductor; the B-phase high-voltage bus is electrically connected to the second end of the first capacitor through the second variable inductor; the second end of the first capacitor is electrically connected to the first end of the second capacitor; the C-phase high-voltage bus is electrically connected to the second end of the second capacitor through the third variable inductor; the second end of the second capacitor is electrically connected to the second end of the third capacitor; the sliding end of the first variable inductor, the sliding end of the second variable inductor and the sliding end of the third variable inductor are all electrically connected to the adjustable control switch.

[0015] Optionally, the compensation capacitor unit is a star-shaped compensation capacitor unit; the compensation capacitor unit includes a first capacitor, a second capacitor and a third capacitor;

[0016] The adjustable reactor includes a first variable inductor, a second variable inductor and a third variable inductor;

[0017] The A-phase high-voltage bus is electrically connected to the first end of the second capacitor through the first variable inductor; the B-phase high-voltage bus is electrically connected to the first end of the first capacitor through the second variable inductor; the C-phase high-voltage bus is electrically connected to the first end of the third capacitor through the third variable inductor; the second end of the first capacitor is electrically connected to the second end of the second capacitor and the second end of the third capacitor; the sliding end of the first variable inductor, the sliding end of the second variable inductor and the sliding end of the third variable inductor are all electrically connected to the adjustable control switch.

[0018] Optionally, the device further includes: a discharge module and a discharge control switch;

[0019] The adjustable reactor is electrically connected to the discharge module through the discharge control switch.

[0020] Optionally, the discharge control switch includes a discharge switch, a discharge control coil, a first time-delay normally open switch, a second time-delay normally closed switch and a second time-delay coil; the discharge switch is coupled to the discharge control coil; the second time-delay normally closed switch and the second time-delay coil are coupled to each other; the first time-delay normally open switch is coupled to the first time-delay coil;

[0021] The A-phase low-voltage bus is electrically connected to the first end of the second time-delay normally closed switch and the first end of the second time-delay coil through the first time-delay normally open switch;

[0022] The second end of the second delayed normally closed switch is electrically connected through the first end of the discharge control coil; the second end of the discharge control coil and the second end of the second delay coil are connected to the C-phase low-voltage bus; the discharge switch is electrically connected to the discharge module.

[0023] Optionally, the maximum allowable closing current of the first starting switch is:

[0024] Among them, I 0 is the rated current of the capacitive power compensation module, X c and X l It is the capacitive reactance and inductive reactance of the marine dynamic leading capacitive power compensation device.

[0025] In a second aspect, an embodiment of the present invention further provides a ship dynamic leading capacitive power compensation method, characterized in that it is applied to the ship dynamic leading capacitive power compensation device described in the first aspect above; the ship dynamic leading capacitive power compensation method comprises:

[0026] Determine the maximum static compensation capacitance of the compensation capacitance unit according to the initial power factor of the load inductive reactance module at the low-speed startup stage, the target required power factor of the load inductive reactance module at different stages, the active power of the load inductive reactance module at the startup completion stage, and the rated voltage of the load inductive reactance module;

[0027] Control the operation of the load inductive reactance module startup module and the capacitive power compensation startup module, and simultaneously receive the real-time power factor outputted at different stages of the load inductive reactance module detected by the power factor detection module;

[0028] The adjustable control switch is controlled to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value; wherein the capacitive power compensation amount of the capacitive power compensation module under different real-time power factors is determined by the adjustable inductance output by the adjustable reactor and the maximum static compensation capacitance of the compensation capacitor unit.

[0029] Optionally, controlling the adjustable control switch to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value includes:

[0030] During the low-speed startup phase of the load inductive reactance module, the real-time power factor detected by the power factor detection module is received as a first real-time power factor, and the adjustable control switch is controlled to output a first control state so that the adjustable reactor outputs a first inductance value;

[0031] When the load inductive reactance module is in the speed increasing stage, the real-time power factor detected by the power factor detection module is received as a second real-time power factor, and the adjustable control switch is controlled to output a second control state so that the adjustable reactor outputs a second inductance value;

[0032] Among them, the first inductance value is smaller than the second inductance value; and the second real-time power factor is larger than the first real-time power factor.

[0033] In the embodiment of the present invention, when the load inductive reactance starting module is working, the external load inductive reactance module starts working, and at this time the capacitive power compensation starting module is controlled to start working, and at the same time the power factor detection module detects the power factor of the external load inductive reactance module in different working stages; the adjustable control switch adjusts the inductive output value of the adjustable reactor according to the different power factors, so that the different inductive output values ​​of the adjustable reactor and the fixed output capacitance value of the compensation capacitor unit determine the different capacitive reactive powers of the capacitive power compensation module, so that the capacitive power compensation module provides different capacitive reactive powers in different starting working stages of the external load inductive reactance module, reduces the requirements for the reactive output of the power grid, reduces or eliminates the impact on the power grid in different starting stages, and also ensures the starting torque of the load at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention;

[0035] Figure 2 It is a specific structural schematic diagram of a marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention;

[0036] Figure 3 It is a specific structural schematic diagram of another marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention;

[0037] Figure 4 It is a specific structural schematic diagram of another marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention;

[0038] Figure 5 It is a flow chart of a method for dynamic leading capacitive power compensation for a ship provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0040] Figure 1 is a structural schematic diagram of a marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention, such as Figure 1 As shown, the device includes: a capacitive power compensation starting module 10, a capacitive power compensation module 20, a load inductive reactance starting module 30 and a power factor detection module 40; the capacitive power compensation module 20 includes an adjustable reactor 21, an adjustable control switch 22 and a compensation capacitor unit 23;

[0041] The load inductive reactance starting module 30 is connected to the three-phase high-voltage bus and the external load inductive reactance module M; the power factor detection module 40 is arranged at the output end of the external load inductive reactance module M; the power factor detection module 40 is electrically connected to the adjustable control switch 22;

[0042] The input end of the adjustable reactor 21 is electrically connected to the three-phase high-voltage bus through the capacitive power compensation starting module 10; the output end of the adjustable reactor 21 is electrically connected in series with the compensation capacitor unit 23; and the adjustable control switch 22 is electrically connected to the control end of the adjustable reactor 21.

[0043] Among them, the load inductive reactance starting module 30 can be used to control the external load inductive reactance module M to take power from the three-phase high-voltage bus on the grid side to start working; the load inductive reactance starting module 30 can include devices such as contactors and air switches; the external load inductive reactance module M can be a motor, and the starting working process of the motor generally includes a low-speed starting stage, a speed-up stage, and a stage where the speed remains constant; the power factor output is different in each stage due to different speed requirements;

[0044] The power factor detection module 40 can detect the power factor of each stage in the process of starting the external load inductive reactance module M; specifically, the power factor of different stages of the low-speed starting stage, the speed-up stage and the speed-keeping stage can be detected; usually the power factor of the low-speed starting stage is relatively low, generally 0.2-0.3; in the speed-up stage, the power factor is 0.7-0.75; the power factor of the speed-keeping stage (start-up completion stage) is the maximum power factor, which can be 0.8; usually in the low-speed starting stage and the speed-up stage, the power factor does not reach the maximum power factor, which will increase the requirements for the reactive power output of the power grid, which will cause an impact on the power grid;

[0045] The capacitive power compensation starting module 10 is used to start when the external load inductive reactance module M starts; thus, the capacitive power compensation module 20 can be used to compensate for reactive power during the low-speed starting stage and the speed-up stage, thereby reducing the requirements for reactive power output of the power grid and avoiding impact on the power grid; specifically, the capacitive power compensation module 20 includes an adjustable reactor 21, an adjustable control switch 22 and a compensation capacitor unit 23; the power factor detection module 40 detects the power factor of the external load inductive reactance module M at different working stages; the adjustable control switch 22 adjusts the inductance output value of the adjustable reactor 21 according to different power factors, and the different inductance output values ​​of the adjustable reactor 21 are related to the power factor. The fixed output capacitance value of the compensation capacitor unit 22 determines the different capacitive reactive powers of the capacitive power compensation module 20, and the adjustable control switch 22 adjusts the different capacitive reactive powers of the capacitive power compensation module 20 according to different power factors; it can be understood that when the power factor is small, the difference between the power factor and the maximum power factor is large, then the inductance output value of the adjustable reactor 21 is small, and the capacitive reactive power of the capacitive power compensation module 20 is large; when the power factor is large, the difference between the power factor and the maximum power factor is small, then the inductance output value of the adjustable reactor 21 is large, and the capacitive reactive power of the capacitive power compensation module 20 is small;

[0046] It should be noted that the fixed output capacitance value of the compensation capacitor unit 23 is the maximum compensation capacitance; the maximum static compensation capacitance of the compensation capacitor unit 23 can be determined by the initial power factor of the external load inductive reactance module M at the low-speed startup stage, the target power factor required at different stages of the load inductive reactance module (generally, the target power factor required at different stages is the maximum power factor, that is, the power factor at rated operation), the active power P at the startup completion stage of the load inductive reactance module, and the rated voltage U of the load inductive reactance module; specifically:

[0047]

[0048] in, The initial power factor of the load inductive reactance module M during the low-speed startup phase; It is the target required power factor at different stages of the load inductive reactance module.

[0049] In the embodiment of the present invention, when the load inductive reactance starting module 30 is working, the external load inductive reactance module M starts working, and at this time, the capacitive power compensation starting module 10 is controlled to start working, and the power factor detection module 40 detects the power factor of the external load inductive reactance module M at different working stages; the adjustable control switch 22 adjusts the inductive output value of the adjustable reactor 21 according to different power factors, so that the different inductive output values ​​of the adjustable reactor 21 and the fixed output capacitance value of the compensation capacitor unit 23 determine the different capacitive reactive powers of the capacitive power compensation module 20, so that the capacitive power compensation module 20 provides different capacitive reactive powers at different starting working stages of the external load inductive reactance module, reduces the requirements for reactive power output of the power grid, reduces or eliminates the impact on the power grid at different starting stages, and also ensures the starting torque of the load at the same time. In addition, the device structure in the embodiment of the present invention is simple, and the cost is lower than that of the frequency converter; at the same time, because the capacitive power compensation starting module 10 and the load inductive reactance starting module 30 start faster in the embodiment of the present invention, the starting speed of the external inductive reactance load module M is greatly improved compared with the frequency converter.

[0050] Optionally, based on the above embodiment, the above embodiment is further refined and optimized as follows: Figure 2 is a schematic diagram of a specific structure of a marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention, such as Figure 2 As shown, the device also includes: a work start control module STT and a transformer TR; the first end of the primary coil of the transformer TR is connected to the A-phase high-voltage bus; the second end of the primary coil of the transformer TR is connected to the C-phase high-voltage bus; the first end of the secondary coil of the transformer TR is connected to the A-phase low-voltage bus; the second end of the secondary coil of the transformer TR is connected to the C-phase low-voltage bus;

[0051] The load inductive reactance module starting module 30 includes a first starting switch ML' and a first starting coil ML; the first starting switch ML' is coupled to the first starting coil ML;

[0052] The A-phase low-voltage bus is connected to the first end of the first starting coil ML through the working start control module STT; the second end of the first starting coil ML is connected to the C-phase low-voltage bus; the first starting switch ML' is connected to the three-phase high-voltage bus.

[0053] Optional, continue to refer to Figure 2 The capacitive power compensation starting module 10 includes: a second starting switch CL', a second starting coil CL, a first delay coil T1 and a first delay normally closed switch T1'; the second starting switch CL' is coupled to the second starting coil CL; the first delay coil T1 and the first delay normally closed switch T1' are coupled to each other;

[0054] The A-phase low-voltage bus is also connected to the first end of the first delay coil T1 through the work start control module STT; the first end of the first delay coil T1 is connected to the C-phase low-voltage bus;

[0055] The A-phase low-voltage bus is also connected to the first end of the first delayed normally closed switch T1' through the working start control module STT; the second end of the first delayed normally closed switch T1' is electrically connected to the first end of the second starting coil CL; the second end of the second starting coil CL is connected to the C-phase low-voltage bus; the second starting switch CL' connects the three-phase high-voltage bus and the adjustable reactor 21.

[0056] Among them, the starting principle of the load inductive reactance module starting module 30 and the capacitive power compensation starting module 10 is: when the working starting control module STT is closed, the first starting coil ML is energized, and the corresponding first starting switch ML' is closed, then the external load inductive reactance module M is started; at the same time, the first delay coil T1 is energized, and since the first delay normally closed switch T1' is in a normally closed state, the second starting coil CL is energized at the same time, and the second starting switch CL' is closed, and the capacitive power compensation module 20 is put into operation; after the first delay coil T1 is energized for a preset time, the preset time is the compensation time length, and the first delay normally closed switch T1' changes from a normally closed state to an open state; then the second starting coil CL is not energized, and the second starting switch CL' is disconnected, and the capacitive power compensation module 20 is not put into operation.

[0057] Optional, continue to refer to Figure 2 , the compensation capacitor unit 23 is an angular supplementary capacitor unit; the compensation capacitor unit includes a first capacitor C1, a second capacitor C2 and a third capacitor C3; the adjustable reactor 21 includes a first variable inductor L1, a second variable inductor L2 and a third variable inductor L3;

[0058] The A-phase high-voltage bus is electrically connected to the first end of the first capacitor C1 and the first end of the third capacitor C3 through the first variable inductor L1; the B-phase high-voltage bus is electrically connected to the second end of the first capacitor C1 through the second variable inductor L2; the second end of the first capacitor C1 is electrically connected to the first end of the second capacitor C2; the C-phase high-voltage bus is electrically connected to the second end of the second capacitor C2 through the third variable inductor C3; the second end of the second capacitor C2 is electrically connected to the second end of the third capacitor C3; the sliding end of the first variable inductor L1, the sliding end of the second variable inductor L2 and the sliding end of the third variable inductor L3 are all electrically connected to the adjustable control switch 22.

[0059] The sliding end of the first variable inductor L1, the sliding end of the second variable inductor L2 and the sliding end of the third variable inductor L3 are all electrically connected to the adjustable control switch 22, so that the adjustable control switch 22 can simultaneously control the inductance values ​​of the first variable inductor L1, the second variable inductor L2 and the third variable inductor L3; the type of the adjustable control switch 22 can include multiple types, which are not limited here;

[0060] When the compensation capacitor unit 23 is a corner-shaped supplementary capacitor unit, the maximum static compensation capacitance of each of the first capacitor L1 , the second capacitor L2 , and the third capacitor L3 is 1 / 3C.

[0061] Optionally, in some other embodiments, Figure 3 FIG. 1 is a schematic diagram of a specific structure of another marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention. Figure 3 As shown, the compensation capacitor unit 23 is a star-shaped supplementary capacitor unit; the compensation capacitor unit 23 includes a first capacitor C1, a second capacitor C2 and a third capacitor C3; the adjustable reactor 21 includes a first variable inductor L1, a second variable inductor L2 and a third variable inductor L3;

[0062] The A-phase high-voltage bus is electrically connected to the first end of the second capacitor C2 through the first variable inductor L1; the B-phase high-voltage bus is electrically connected to the first end of the first capacitor C1 through the second variable inductor L2; the C-phase high-voltage bus is electrically connected to the first end of the third capacitor C3 through the third variable inductor L3; the second end of the first capacitor C1 is electrically connected to the second end of the second capacitor C2 and the second end of the third capacitor C3; the sliding end of the first variable inductor L1, the sliding end of the second variable inductor L2 and the sliding end of the third variable inductor L3 are all electrically connected to the adjustable control switch 22.

[0063] When the compensation capacitor unit 23 is a star-shaped supplementary capacitor unit, the maximum static compensation capacitance of the first capacitor C1, the second capacitor C2 and the third capacitor C3 is 1 / 3 C. The adjustable control switch 22 in this embodiment may include multiple types, which are not limited here.

[0064] Optional, Figure 4 FIG. 1 is a schematic diagram of a specific structure of another marine dynamic leading capacitive power compensation device provided by an embodiment of the present invention. Figure 4 As shown, the device further includes: a discharge module 50 and a discharge control switch 60; the adjustable reactor 21 is electrically connected to the discharge module 50 through the discharge control switch 60. When the second start switch CL' is disconnected and the capacitive power compensation module 20 quits compensating the external inductive load module M, the discharge control switch 60 is closed, so that the capacitive power compensation module 20 and the discharge module 70 form a closed loop, and the remaining charge in the capacitive power compensation module 20 will be quickly discharged through the discharge module 70; the discharge module 50 includes a discharge resistor; when the discharge resistor reaches a certain temperature, the discharge stops, so as to achieve discharge protection for the capacitive power compensation module 20.

[0065] Optionally, the discharge control switch is further refined below, and further reference is made to Figure 4 The discharge control switch 60 includes a discharge switch RL', a discharge control coil RL, a first time-delay normally open switch T1", a second time-delay normally closed switch T2' and a second time-delay coil T2; the discharge switch RL' is coupled to the discharge control coil RL; the second time-delay normally closed switch T2' and the second time-delay coil T2 are coupled; the first time-delay normally open switch T1' is coupled to the first time-delay coil T1;

[0066] The A-phase low-voltage busbar is electrically connected to the first end of the second delayed normally closed switch T2' and the first end of the second delay coil T2 through the first delayed normally open switch T1'';

[0067] The second end of the second time-delay normally closed switch T2' is electrically connected through the first end of the discharge control coil RL; the second end of the discharge control coil RL and the second end of the second time-delay coil T2 are connected to the C-phase low-voltage bus;

[0068] The discharge switch RL′ is electrically connected to the discharge module 50 .

[0069] Among them, after the first delay coil T1 is energized for a preset time, the preset time is the compensation time, and the first delay normally closed switch T1' changes from a normally closed state to an open state; then the second starting coil CL is not energized, and the second starting switch CL' is disconnected, and the capacitive power compensation module 20 is not put into operation; at the same time, the first delay normally open switch T1" changes from a normally open state to a closed state, and the second delay coil T2 is energized, and the corresponding second delay normally closed switch T2' is in a closed state, then the discharge control coil RL is energized, and the discharge switch RL' is correspondingly closed, and the discharge module 50 works; and after the preset time, the preset time is the discharge time, and the second delay normally closed switch T2' changes from a closed state to an open state, and the discharge control coil RL is not energized, and the discharge switch RL' is turned off, and the discharge module 50 ends the discharge.

[0070] Optional, see Figure 2-4 , the maximum allowable closing current of the second starting switch CL' is Among them I 0 is the rated current of the capacitive power compensation module 20, X c and X l is the capacitive reactance and inductive reactance of the device. Specifically, the maximum allowable closing current of the second starting switch CL' is determined by the rated current of the capacitive power compensation module 20 and the capacitive reactance and inductive reactance in the capacitive power compensation module 20, the capacitive reactance and inductive reactance in the capacitive power compensation starting module 10, the capacitive reactance and inductive reactance in the load inductive reactance starting module 30, and the capacitive reactance and inductive reactance in the power factor detection module 40 of the device; in this embodiment, the maximum allowable closing current of the second starting switch CL' satisfies: Therefore, the capacitive power compensation module 20 is protected, and the capacitive power compensation module 20 is not tripped or burned due to a short circuit caused by a closing surge current.

[0071] Based on the same inventive concept, an embodiment of the present invention further provides a marine dynamic leading capacitive power compensation method, which is applied to the marine dynamic leading capacitive power compensation device of the above embodiment; Figure 5 FIG. 1 is a flow chart of a method for dynamic leading capacitive power compensation for a ship provided by an embodiment of the present invention, such as Figure 5 As shown, the method comprises the following steps:

[0072] S110, determining the maximum static compensation capacitance of the compensation capacitance unit according to the initial power factor of the load inductive reactance module at the low-speed startup stage, the target required power factor of the load inductive reactance module at different stages, the active power of the load inductive reactance module at the startup completion stage, and the rated voltage of the load inductive reactance module;

[0073] Among them, the maximum static compensation capacitance C of the compensation capacitance unit is:

[0074]

[0075] in, is the initial power factor of the external load inductive reactance module M at the low-speed starting stage; is the target required power factor of the load inductive reactance module at different stages (generally, the target required power factor at different stages is the maximum power factor); P is the active power of the load inductive reactance module at the start-up completion stage; U is the rated voltage of the load inductive reactance module.

[0076] S120, controlling the load inductive reactance module startup module and the capacitive power compensation startup module to work, and simultaneously receiving the real-time power factor outputted at different stages of the load inductive reactance module detected by the power factor detection module;

[0077] S130, controlling the adjustable control switch to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value; wherein the capacitive power compensation amount of the capacitive power compensation module under different real-time power factors is determined by the adjustable inductance output by the adjustable reactor and the maximum static compensation capacitance of the compensation capacitor unit.

[0078] In this embodiment, the power factor detection module detects the power factor of the external load inductive reactance module M in different working stages; the adjustable control switch adjusts the inductive output value of the adjustable reactor according to different power factors, so that the different inductive output values ​​of the adjustable reactor and the fixed output capacitance value of the compensation capacitor unit determine the different capacitive reactive powers of the capacitive power compensation module, so that the capacitive power compensation module provides different capacitive reactive powers in different startup working stages of the external load inductive reactance module, reduces the requirements for the reactive output of the power grid, reduces or eliminates the impact on the power grid in different startup stages, and also ensures the starting torque of the load at the same time.

[0079] Optionally, based on the above embodiment, step S120 is further refined, and the adjustable control switch is controlled to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value, including:

[0080] During the low-speed startup phase of the load inductive reactance module, the real-time power factor detected by the receiving power factor detection module is a first real-time power factor, and the adjustable control switch is controlled to output a first control state so that the adjustable reactor outputs a first inductance value;

[0081] During the speed increase stage of the load inductive reactance module, the real-time power factor detected by the receiving power factor detection module is a second real-time power factor, and the adjustable control switch is controlled to output a second control state so that the adjustable inductor outputs a second inductance value; wherein the first inductance value is less than the second inductance value; and the second real-time power factor is greater than the first real-time power factor.

[0082] Specifically, when the power factor is the first power factor (the first power factor is greater than or equal to the initial power factor), the difference between the first power factor and the maximum power factor is large, and the inductance output value of the adjustable reactor 21 is small (it can be understood that when the first power factor is equal to the initial power factor, the inductance output value of the adjustable reactor 21 is adjusted to 0; when the first power factor is greater than the initial power factor, the inductance output value of the adjustable reactor 21 can be adjusted to 1 / 2 of the inductance value of the adjustable reactor 21), the capacitance of the capacitive power compensation module 20 is The reactive power of the capacitive power compensation module 20 is relatively large; when the power factor is the second power factor, the difference between the second power factor and the maximum power factor is relatively small, and the inductance output value of the adjustable reactor 21 is relatively large (such as: when the second power factor is around 0.7, the inductance output value of the adjustable reactor 21 can be the inductance of all adjustable reactors 21), and the capacitive reactive power of the capacitive power compensation module 20 is relatively small, ensuring that the line will not be over-compensated; when the motor is started and runs normally, the power factor is the maximum, and the capacitive power compensation module 20 exits compensation.

[0083] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A marine dynamic leading capacitive power compensation device, characterized in that: include: Capacitive power compensation starting module, capacitive power compensation module, load inductive reactance starting module and power factor detection module; the capacitive power compensation module includes an adjustable reactor, an adjustable control switch and a compensation capacitor unit; The load inductive reactance starting module is connected to the three-phase high-voltage bus and the external load inductive reactance module; the power factor detection module is arranged at the output end of the external load inductive reactance module; the power factor detection module is electrically connected to the adjustable control switch; The input end of the adjustable reactor is electrically connected to the three-phase high-voltage bus through the capacitive power compensation starting module; the output end of the adjustable reactor is electrically connected in series with the compensation capacitor unit; and the adjustable control switch is electrically connected to the control end of the adjustable reactor.

2. The marine dynamic leading capacitive power compensation device according to claim 1 is characterized in that: Also includes: A work start control module and a transformer; the first end of the primary coil of the transformer is connected to the A-phase high-voltage bus; the second end of the primary coil of the transformer is connected to the C-phase high-voltage bus; the first end of the secondary coil of the transformer is connected to the A-phase low-voltage bus; the second end of the secondary coil of the transformer is connected to the C-phase low-voltage bus; The load inductive reactance module starting module includes a first starting switch and a first starting coil; the first starting switch is coupled to the first starting coil; The A-phase low-voltage bus is connected to the first end of the first starting coil through the work start control module; the second end of the first starting coil is connected to the C-phase low-voltage bus; and the first starting switch is connected to the three-phase high-voltage bus.

3. The marine dynamic leading capacitive power compensation device according to claim 2 is characterized in that: The capacitive power compensation starting module includes: a second starting switch, a second starting coil, a first delay coil and a first delay normally closed switch; the second starting switch is coupled and connected with the second starting coil; the first delay coil and the first delay normally closed switch are coupled and connected; The A-phase low-voltage bus is also connected to the first end of the first delay coil through the work start control module; the first end of the first delay coil is connected to the C-phase low-voltage bus; The A-phase low-voltage bus is also connected to the first end of the first delayed normally closed switch through the working start control module; the second end of the first delayed normally closed switch is electrically connected to the first end of the second starting coil; the second end of the second starting coil is connected to the C-phase low-voltage bus; the second starting switch connects the three-phase high-voltage bus and the adjustable reactor.

4. The marine dynamic leading capacitive power compensation device according to claim 1, characterized in that: The compensation capacitor unit is an angular supplementary capacitor unit; the compensation capacitor unit includes a first capacitor, a second capacitor and a third capacitor; the adjustable reactor includes a first variable inductor, a second variable inductor and a third variable inductor; The A-phase high-voltage bus is electrically connected to the first end of the first capacitor and the first end of the third capacitor through the first variable inductor; the B-phase high-voltage bus is electrically connected to the second end of the first capacitor through the second variable inductor; the second end of the first capacitor is electrically connected to the first end of the second capacitor; the C-phase high-voltage bus is electrically connected to the second end of the second capacitor through the third variable inductor; the second end of the second capacitor is electrically connected to the second end of the third capacitor; the sliding end of the first variable inductor, the sliding end of the second variable inductor and the sliding end of the third variable inductor are all electrically connected to the adjustable control switch.

5. The marine dynamic leading capacitive power compensation device according to claim 1, characterized in that: The compensation capacitor unit is a star-shaped compensation capacitor unit; the compensation capacitor unit includes a first capacitor, a second capacitor and a third capacitor; The adjustable reactor includes a first variable inductor, a second variable inductor and a third variable inductor; The A-phase high-voltage bus is electrically connected to the first end of the second capacitor through the first variable inductor; the B-phase high-voltage bus is electrically connected to the first end of the first capacitor through the second variable inductor; the C-phase high-voltage bus is electrically connected to the first end of the third capacitor through the third variable inductor; the second end of the first capacitor is electrically connected to the second end of the second capacitor and the second end of the third capacitor; the sliding end of the first variable inductor, the sliding end of the second variable inductor and the sliding end of the third variable inductor are all electrically connected to the adjustable control switch.

6. The marine dynamic leading capacitive power compensation device according to claim 3, characterized in that: Also includes: Discharge module and discharge control switch; The adjustable reactor is electrically connected to the discharge module through the discharge control switch.

7. The marine dynamic leading capacitive power compensation device according to claim 6, characterized in that: The discharge control switch includes a discharge switch, a discharge control coil, a first time-delay normally open switch, a second time-delay normally closed switch and a second time-delay coil; the discharge switch is coupled to the discharge control coil; the second time-delay normally closed switch is coupled to the second time-delay coil; the first time-delay normally open switch is coupled to the first time-delay coil; The A-phase low-voltage bus is electrically connected to the first end of the second time-delay normally closed switch and the first end of the second time-delay coil through the first time-delay normally open switch; The second end of the second delayed normally closed switch is electrically connected through the first end of the discharge control coil; the second end of the discharge control coil and the second end of the second delay coil are connected to the C-phase low-voltage bus; the discharge switch is electrically connected to the discharge module.

8. The marine dynamic leading capacitive power compensation device according to claim 2, characterized in that: The maximum allowable closing current of the first starting switch is: Where, I0 is the rated current of the capacitive power compensation module, X c and X l It is the capacitive reactance and inductive reactance of the marine dynamic leading capacitive power compensation device.

9. A method for dynamic leading capacitive power compensation for a ship, characterized in that: The marine dynamic leading capacitive power compensation device applied to any one of claims 1 to 8 above; the marine dynamic leading capacitive power compensation method comprises: Determine the maximum static compensation capacitance of the compensation capacitance unit according to the initial power factor of the load inductive reactance module at the low-speed startup stage, the target required power factor of the load inductive reactance module at different stages, the active power of the load inductive reactance module at the startup completion stage, and the rated voltage of the load inductive reactance module; Control the operation of the load inductive reactance module startup module and the capacitive power compensation startup module, and simultaneously receive the real-time power factor outputted at different stages of the load inductive reactance module detected by the power factor detection module; The adjustable control switch is controlled to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value; wherein the capacitive power compensation amount of the capacitive power compensation module under different real-time power factors is determined by the adjustable inductance output by the adjustable reactor and the maximum static compensation capacitance of the compensation capacitor unit.

10. The marine dynamic leading capacitive power compensation method according to claim 9, characterized in that: Controlling the adjustable control switch to output different control states according to the real-time power factor so that the adjustable reactor outputs an adjustable inductance value includes: During the low-speed startup phase of the load inductive reactance module, the real-time power factor detected by the power factor detection module is received as a first real-time power factor, and the adjustable control switch is controlled to output a first control state so that the adjustable reactor outputs a first inductance value; When the load inductive reactance module is in the speed increasing stage, the real-time power factor detected by the power factor detection module is received as a second real-time power factor, and the adjustable control switch is controlled to output a second control state so that the adjustable reactor outputs a second inductance value; Among them, the first inductance value is smaller than the second inductance value; and the second real-time power factor is larger than the first real-time power factor.

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