Main winch generator grid-connected control device and method thereof

Abstract

The main winch generator grid-connected control device comprises an auxiliary control cabinet, a wire inlet cabinet is arranged on the right side of the auxiliary control cabinet, a power supply cabinet is arranged on the right side of the wire inlet cabinet, and an inverter cabinet is arranged on the right side of the power supply cabinet. DC loop pre-charging is carried out by disconnecting a grounding switch and switching on an auxiliary voltage switch and a charging switch, and a main isolation switch and a main contactor are switched on; speed control is selected on a generator control panel, the initial torque + / -2% is set, and a frequency converter is started at the background or locally in a control room; at the moment, in an umbrella ladder type novel power generation technology test project, an acting umbrella is opened, a generator brake is loosened, a friction drum drives a speed reducer to work, the speed reducer drives the generator to generate power, and torque parameters are adjusted to match the wind speed condition; a power supply with fluctuating frequency and voltage generated by the generator is converted into a direct current through the inverter module, then the direct current is output into a stable and constant-frequency alternating current through the LCL filter module, and finally the alternating current is connected with a 10KV external network through step-up transformation and grid connection.

Description

Technical Field

[0001] The invention relates to the technical field of grid-connected control, and in particular to a main winch generator grid-connected control device and method thereof. Background Art

[0002] With the continuous development of wind power technology, wind power generation needs to be connected to the grid. The existing technology has the following shortcomings: 1. Complexity and cost: The design of fuzzy controller is relatively complex, requiring a lot of debugging and experience accumulation, which increases the difficulty and cost of system implementation; 2. Limited adaptability: Although fuzzy control has certain adaptive capabilities, its adjustment effect may not be ideal when facing extreme working conditions or unknown disturbances, and it is difficult to ensure that the optimal control effect can be achieved under various circumstances; 3. Real-time problem: Although the online adjustment of PID parameters improves the flexibility of control, in situations with high real-time requirements, the rapid adjustment of parameters may be limited by the calculation speed, affecting the response speed of the system; 4. Integration and compatibility: With the development of smart grid technology, higher requirements are placed on the integration and compatibility of generator grid-connected control systems. Existing control strategies may have certain limitations in terms of integration with other smart devices or systems. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a main winch generator grid-connected control device and method thereof, which solves the problems raised by the above-mentioned background technology.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions: a main winch generator grid-connected control device, including an auxiliary control cabinet, a line incoming cabinet is provided on the right side of the auxiliary control cabinet, a power supply cabinet is provided on the right side of the line incoming cabinet, an inverter cabinet is provided on the right side of the power supply cabinet, and control electronic devices and customer I / O connections are provided inside the auxiliary control cabinet.

[0005] Preferably, an input cable lead-in hole is provided inside the incoming line cabinet, an input terminal is provided above the input cable lead-in hole, a main isolating switch is provided above the input terminal, a grounding switch is provided above the main isolating switch, an AC fuse is provided above the grounding switch, a charging resistor is provided above the AC fuse, a main contactor is provided above the charging resistor, an auxiliary voltage switch is provided above the main contactor, a charging switch is provided above the auxiliary voltage switch, a PE busbar is provided next to the input cable lead-in hole, and an auxiliary contactor is provided next to the charging resistor.

[0006] Preferably, two power supply modules are provided inside the power supply cabinet, a plurality of DC fuses are provided above the power supply modules, and an LCL filter module is provided between the two power supply modules.

[0007] Preferably, two inverter modules are provided inside the inverter cabinet, and a plurality of the DC fuses are provided above the inverter modules.

[0008] A method for a main winch generator grid-connected control device, characterized in that it comprises the following steps: Step 1: disconnect the grounding switch, close the auxiliary voltage switch and the charging switch to pre-charge the DC circuit, and close the main isolating switch and the main contactor; Step 2: Select "speed control" on the generator control panel, set the initial torque to "±2%", and start the inverter in the control room or locally; Step 3: At this time, the working parachute in the umbrella-ladder new power generation technology test project is opened, the working brake of the generator is released, the friction drum drives the reducer to work, the reducer drives the generator to generate electricity, and the torque parameters are adjusted to match the wind speed; Step 4: The power with frequency and voltage fluctuations generated by the generator is converted into direct current through the inverter module, and then output as stable constant frequency alternating current through the LCL filter module, and finally connected to the 10KV external network through the boost transformer.

[0009] Preferably, the inverter module includes a three-phase bridge half-controlled rectifier circuit, a load unloading circuit, an inverter circuit and a grid-connected switch, and the control method of the inverter module when the generator brakes is as follows: Step 61, when the generator brakes, the inverter circuit of the control electronic device stops inversion; Step 62, controlling the electronic device to disconnect the grid-connected switch; Step 63: The control electronic device controls the unloading circuit to unload the load.

[0010] Preferably, when the DC voltage is higher than a preset unloading voltage, the control electronic device controls the unloading circuit to unload so as to suppress the rise of the DC voltage; specifically, the following steps are included: Step 1: Determine the initial duty cycle according to the following formula:

[0011] in, is the initial duty cycle, is the preset unloading voltage, is the preset full unloading voltage, It is a DC voltage, the preset full unloading voltage Greater than the preset unloading voltage ; Step 71, adjusting the duty cycle of the power switch device in the unloading circuit to the initial duty cycle; Step 72, controlling the duty cycle of the power switch device in the unloading circuit to increase from the initial duty cycle to 100%; Step 73, when the unloading duty cycle of the unloading circuit reaches 100% complete unloading state, if the DC voltage is still on an upward trend and reaches a preset maximum voltage threshold, the duty cycle of the power switch device in the three-phase bridge half-controlled rectifier circuit is controlled to increase from zero according to the preset value, and at the same time, the output current of the generator is limited; the DC voltage is detected in real time, and if the DC voltage is still on an upward trend and reaches the preset braking condition, the braking action is executed, and if the DC voltage drops to the preset maximum voltage threshold or below, the power switch device in the three-phase bridge half-controlled rectifier circuit is disconnected.

[0012] Beneficial Effects The present invention provides a main winch generator grid-connected control device and method thereof. Compared with the prior art, it has the following beneficial effects: 1. The main winch generator grid-connected control device and method thereof disconnect the grounding switch, close the auxiliary voltage switch and the charging switch to pre-charge the DC circuit, and close the main isolating switch and the main contactor; select "speed control" on the generator control panel, set the initial torque "±2%", and start the inverter in the control room background or locally; at this time, the working umbrella in the umbrella-ladder new power generation technology test project is opened, the generator working brake is released, the friction drum belt reducer works, the reducer drives the generator to generate electricity, and the torque parameters are adjusted to match the wind speed; the power supply with frequency and voltage fluctuations emitted by the generator is converted into direct current through the inverter module, and then output as stable constant frequency alternating current through the LCL filter module, and finally connected to the 10KV external network through the step-up transformer; in this way, the output frequency and voltage of the generator are not limited, and no matter how much the output frequency and voltage of the generator are, it can be connected to the grid through the converter.

[0013] 2. The main winch generator grid-connected control device and method thereof, when the generator brakes, first block the drive signal of the inverter circuit power switch device, stop the inverter output, and then disconnect the grid-connected switch, which can prevent the grid energy from flowing back to the unloading circuit and consuming the grid energy. Control the unloading circuit to unload until it is completely unloaded (the unloading resistor is fully connected), then control the power switch device of the lower bridge arm of the three-phase bridge-type semi-controlled rectifier to conduct, and at the same time, limit the output current of the generator to prevent the generator from being burned by excessive current; the unloading circuit cooperates with the three-phase bridge-type semi-controlled rectifier to achieve gradual unloading and ultimately achieve the purpose of safe braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a schematic diagram of the internal structure of the present invention.

[0015] In the figure: A, auxiliary control cabinet; B, incoming line cabinet; C, power supply cabinet; D, inverter cabinet; 1, input cable lead hole; 2, input terminal; 3, main isolating switch; 4, grounding switch; 5, AC fuse; 6, charging resistor; 7, main contactor; 8, auxiliary voltage switch; 9, charging switch; 10, DC fuse; 11, LCL filter module; 12, power supply module; 13, inverter module. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] See also Figure 1-2The present invention provides a technical solution: a main winch generator grid-connected control device, comprising an auxiliary control cabinet A, an incoming line cabinet B is arranged on the right side of the auxiliary control cabinet A, a power supply cabinet C is arranged on the right side of the incoming line cabinet B, an inverter cabinet D is arranged on the right side of the power supply cabinet C, a control electronic device and a customer I / O connection are arranged inside the auxiliary control cabinet A, an input cable lead hole 1 is arranged inside the incoming line cabinet B, an input terminal 2 is arranged above the input cable lead hole 1, a main isolating switch 3 is arranged above the input terminal 2, a grounding switch 4 is arranged above the main isolating switch 3, an AC fuse 5 is arranged above the grounding switch 4, a charging resistor 6 is arranged above the AC fuse 5, a main contactor 7 is arranged above the charging resistor 6, an auxiliary voltage switch 8 is arranged above the main contactor 7, a charging switch 9 is arranged above the auxiliary voltage switch 8, a PE busbar is arranged next to the input cable lead hole 1, a secondary contactor is arranged next to the charging resistor 6, two power supply modules 12 are arranged inside the power supply cabinet C, and a plurality of DC fuses 10 are arranged above the power supply module 12, An LCL filter module 11 is provided between the two power supply modules 12, two inverter modules 13 are provided inside the inverter cabinet D, and a plurality of DC fuses 10 are provided above the inverter module 13; the device disconnects the grounding switch 4, closes the auxiliary voltage switch 8 and the charging switch 9 to pre-charge the DC circuit, and closes the main isolating switch 3 and the main contactor 7; the generator control panel selects "speed control", sets the initial torque "±2%", and starts the inverter in the control room background or locally; at this time, the working umbrella in the umbrella-ladder new power generation technology test project is opened, the working brake of the generator is released, the friction drum belt reducer works, the reducer drives the generator to generate electricity, and the torque parameters are adjusted to match the wind speed; the power supply with frequency and voltage fluctuations emitted by the generator is converted into direct current through the inverter module 13, and then output as stable constant frequency alternating current through the LCL filter module 11, and finally connected to the 10KV external network through the step-up transformer, so that the output frequency and voltage of the generator are not limited, and no matter how much the output frequency and voltage of the generator are, it can be connected to the grid through the converter.

[0018] Furthermore, the inverter module 13 includes a three-phase bridge half-controlled rectifier circuit, a load unloading circuit, an inverter circuit and a grid-connected switch. The control method of the inverter module 13 during generator braking is as follows: Step 61, when the generator brakes, the inverter circuit of the control electronic device stops inversion; Step 62, controlling the electronic device to disconnect the grid-connected switch; Step 63, controlling the electronic device to control the unloading circuit to unload; When the DC voltage is higher than the preset unloading voltage, the control electronic device controls the unloading circuit to unload the load to suppress the rise of the DC voltage; specifically, the following steps are included: Step 1: Determine the initial duty cycle according to the following formula:

[0019] in, is the initial duty cycle, is the preset unloading voltage, is the preset full unloading voltage, It is a DC voltage, the preset full unloading voltage Greater than the preset unloading voltage ; Step 71, adjusting the duty cycle of the power switch device in the unloading circuit to the initial duty cycle; Step 72, controlling the duty cycle of the power switch device in the unloading circuit to increase from the initial duty cycle to 100% according to a preset value; Step 73, when the unloading duty cycle of the unloading circuit reaches 100% complete unloading state, if the DC voltage is still on an upward trend and reaches the preset maximum voltage threshold, the duty cycle of the power switch device in the three-phase bridge half-controlled rectifier circuit is controlled to increase from zero according to the preset fifth step length, and at the same time, the output current of the generator is limited; the DC voltage is detected in real time, and if the DC voltage is still on an upward trend and reaches the preset braking condition, the braking action is executed, and if the DC voltage drops to the preset maximum voltage threshold or below, the power switch device in the three-phase bridge half-controlled rectifier circuit is disconnected.

[0020] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0021] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions. The sentence "includes an element defined by ... does not exclude the existence of other identical elements in the process, method, article or device including the element".

[0022] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A main winch generator grid-connected control device, comprising an auxiliary control cabinet (A), characterized in that: A line incoming cabinet (B) is disposed on the right side of the auxiliary control cabinet (A), a power supply cabinet (C) is disposed on the right side of the line incoming cabinet (B), an inverter cabinet (D) is disposed on the right side of the power supply cabinet (C), and control electronic devices and customer I / O connections are disposed inside the auxiliary control cabinet (A).

2. A main winch generator grid-connected control device according to claim 1, characterized in that: An input cable lead hole (1) is provided inside the incoming cable cabinet (B), an input terminal (2) is provided above the input cable lead hole (1), a main isolating switch (3) is provided above the input terminal (2), an earthing switch (4) is provided above the main isolating switch (3), an AC fuse (5) is provided above the earthing switch (4), a charging resistor (6) is provided above the AC fuse (5), a main contactor (7) is provided above the charging resistor (6), an auxiliary voltage switch (8) is provided above the main contactor (7), a charging switch (9) is provided above the auxiliary voltage switch (8), a PE busbar is provided next to the input cable lead hole (1), and an auxiliary contactor is provided next to the charging resistor (6).

3. A main winch generator grid-connected control device according to claim 2, characterized in that: Two power supply modules (12) are arranged inside the power supply cabinet (C), a plurality of DC fuses (10) are arranged above the power supply modules (12), and an LCL filter module (11) is arranged between the two power supply modules (12).

4. A main winch generator grid-connected control device according to claim 3, characterized in that: Two inverter modules (13) are arranged inside the inverter cabinet (D), and a plurality of DC fuses (10) are arranged above the inverter modules (13).

5. A method for controlling a main winch generator grid connection according to claim 4, characterized in that: The following steps are involved: Step 1: disconnect the grounding switch, close the auxiliary voltage switch and the charging switch to pre-charge the DC circuit, and close the main isolating switch and the main contactor; Step 2: Select "speed control" on the generator control panel, set the initial torque to "±2%", and start the inverter in the control room background or locally; Step 3: At this time, the working parachute in the umbrella-ladder new power generation technology test project is opened, the working brake of the generator is released, the friction drum drives the reducer to work, the reducer drives the generator to generate electricity, and the torque parameters are adjusted to match the wind speed; Step 4: The power with frequency and voltage fluctuations generated by the generator is converted into direct current through the inverter module, and then output as stable constant frequency alternating current through the LCL filter module, and finally connected to the 10KV external network through the boost transformer.

6. A main winch generator grid-connected control device according to claim 5, characterized in that: The inverter module (13) comprises an electronic brake switch, a three-phase bridge half-controlled rectifier circuit, a load unloading circuit, an inverter circuit and a grid-connected switch. The control method of the inverter module (13) during generator braking is the following steps: Step 61, when the generator brakes, the inverter circuit of the control electronic device stops inversion; Step 62, controlling the electronic device to disconnect the grid-connected switch; Step 63, controlling the electronic device to control the unloading circuit to unload; Step 64: The control electronic device controls the electronic brake switch to close.

7. A main winch generator grid-connected control device and method according to claim 6, characterized in that: When the DC voltage is higher than the preset unloading voltage, the control electronic device controls the unloading circuit to unload the load, so as to suppress the rise of the DC voltage; specifically, the following steps are included: Step 1: Determine the initial duty cycle according to the following formula: Wherein, D1 is the initial duty cycle, U3 is the preset unloading voltage, U4 is the preset full unloading voltage, Udc is the DC voltage, and the preset full unloading voltage U4 is greater than the preset unloading voltage U3; Step 71, adjusting the duty cycle of the power switch device in the unloading circuit to the initial duty cycle; Step 72, controlling the duty cycle of the power switch device in the unloading circuit to increase from the initial duty cycle to 100% according to a preset value; Step 73, when the unloading duty cycle of the unloading circuit reaches 100% complete unloading state, if the DC voltage is still on an upward trend and reaches the preset maximum voltage threshold, the duty cycle of the power switch device in the three-phase bridge half-controlled rectifier circuit is controlled to increase from zero according to the preset fifth step length, and at the same time, the output current of the generator is limited; the DC voltage is detected in real time, and if the DC voltage is still on an upward trend and reaches the preset braking condition, the braking action is executed, and if the DC voltage drops to the preset maximum voltage threshold or below, the power switch device in the three-phase bridge half-controlled rectifier circuit is disconnected.

Images