阅读说明：本技术 一种励磁系统的脉冲混合传输方法及系统 (Pulse mixed transmission method and system of excitation system ) 是由 顾建嵘 朱红伟 单华鹏 彭钢 王斌 张绍峰 刘玉林 宋文渊 于 2021-07-12 设计创作，主要内容包括：本发明公开了一种发电机励磁系统技术领域的励磁系统的脉冲混合传输方法及系统。系统包括励磁调节装置和功率柜控制器,励磁调节装置将对应单个整流支路的控制数据报文信号与触发脉冲信号先后结合设置,并将对应所有整流支路的结合后信号,按照功率柜整流桥触发脉冲时序通过串行控制总线进行传输；其中,对应单个整流支路的控制数据报文包括特征码,不同特征码表征与控制数据报文结合的触发脉冲信号所对应的整流支路；功率柜控制器解析报文脉冲序列中的各支路脉冲,根据特征码以及触发脉冲信号的接收时刻和脉宽,生成功率柜整流桥中相应整流支路的驱动脉冲。本发明能够简化调试步骤和工程成本,保证励磁系统的可靠性,进而提高发电机运行的稳定性。(The invention discloses a pulse mixed transmission method and a pulse mixed transmission system of an excitation system in the technical field of generator excitation systems. The system comprises an excitation adjusting device and a power cabinet controller, wherein the excitation adjusting device combines and sets a control data message signal corresponding to a single rectifying branch with a trigger pulse signal in sequence, and transmits the combined signals corresponding to all the rectifying branches through a serial control bus according to a power cabinet rectifying bridge trigger pulse time sequence; the control data message corresponding to a single rectification branch comprises feature codes, and different feature codes represent the rectification branches corresponding to the trigger pulse signals combined with the control data message; and the power cabinet controller analyzes each branch pulse in the message pulse sequence and generates a driving pulse of a corresponding rectifying branch in a rectifier bridge of the power cabinet according to the feature code and the receiving time and the pulse width of the trigger pulse signal. The invention can simplify the debugging step and the engineering cost, ensure the reliability of the excitation system and further improve the running stability of the generator.)

1. A pulse mixed transmission method suitable for an excitation system power cabinet is characterized by comprising the following steps:

combining and setting the control data message signal corresponding to a single rectifying branch with the trigger pulse signal in sequence;

transmitting the combined signals corresponding to all the rectification branches through a serial control bus according to a power cabinet rectifier bridge trigger pulse time sequence;

the control data message corresponding to a single rectification branch comprises feature codes, and different feature codes represent the rectification branches corresponding to the trigger pulse signals combined with the control data message.

2. The method of claim 1, further comprising transmitting a pulse blocking message or a pulse train trigger message over a serial control bus, the pulse blocking message including a feature code corresponding to a pulse blocking command; the pulse train trigger message includes a feature code corresponding to the pulse train trigger instruction.

3. The method of claim 1, wherein the signature bit width is set to 3 bits, 000 corresponding to pulse blocking; 100. 010, 001, 011, 101 and 110 respectively correspond to different rectifying branches of the rectifying bridge of the power cabinet; 111 corresponds to a burst firing command.

4. A control method for a rectifier bridge of an excitation system power cabinet is characterized by comprising the following steps:

receiving a message pulse sequence transmitted through a serial control bus, wherein the message pulse sequence comprises a plurality of branch pulses arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal corresponding to a single rectifier branch with a trigger pulse signal, the control data message corresponding to the single rectifier branch comprises feature codes, and different feature codes represent rectifier branches corresponding to the trigger pulse signals combined with the control data messages;

sequentially acquiring and analyzing each branch pulse in the message pulse sequence to obtain a feature code for controlling a data message signal in the branch pulse and a corresponding rectification branch;

and acquiring a trigger pulse signal in the branch pulse, and generating a driving pulse of a corresponding rectifying branch in the rectifier bridge of the power cabinet according to the rectifying branch corresponding to the feature code and the receiving time and the pulse width of the trigger pulse signal.

5. The method of claim 4, further comprising, in response to not receiving a message within a set time period, determining that communication of the serial control bus is interrupted, and outputting a communication failure signal.

6. The method of claim 4, wherein: further comprising: receiving a pulse blocking message or a pulse train triggering message transmitted through a serial control bus, analyzing to obtain a feature code, and according to the feature code: responding to the received pulse blocking message, executing a pulse blocking instruction, and stopping the output of the driving pulses of all the rectifying branches; and responding to the received pulse train trigger message, executing a pulse train sending instruction, and sending continuous trigger pulses to all the rectifying branches.

7. A pulse mixed transmission system of an excitation system is characterized by comprising an excitation adjusting device and a power cabinet, wherein the excitation adjusting device is connected with the power cabinet through a serial control bus; the power cabinet comprises a power cabinet controller and a power cabinet rectifier bridge;

the excitation adjusting device transmits a message pulse sequence to the power cabinet controller through the serial control bus; the message pulse sequence comprises a plurality of branch pulses which are arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal and a trigger pulse signal of a corresponding single rectifying branch, the control data message corresponding to the single rectifying branch comprises feature codes, and different feature codes represent rectifying branches corresponding to the trigger pulse signals combined with the control data message;

and the power cabinet controller receives the message pulse sequence, acquires the branch pulse, the feature code for controlling the data message signal in the branch pulse, the corresponding rectification branch and the trigger pulse signal in the branch pulse, and generates the driving pulse of the corresponding rectification branch in the power cabinet rectifier bridge according to the receiving time and the pulse width of the rectification branch corresponding to the feature code and the trigger pulse signal.

8. The pulse hybrid transmission system of the excitation system according to claim 7, wherein the pulse train of the message transmitted from the excitation adjusting device to the power cabinet controller further includes a pulse blocking message or a pulse train trigger message, and the pulse blocking message includes a feature code corresponding to a pulse blocking command; the pulse train trigger message comprises a feature code corresponding to the pulse train trigger instruction;

the power cabinet controller stops the output of the driving pulses of all the rectifying branches in response to the received pulse blocking message; and the power cabinet controller responds to the received pulse train trigger message, executes the pulse train to send out an instruction and sends out continuous trigger pulses to all the rectifying branches.

9. The pulse mixing transmission system of an excitation system according to claim 7, wherein said serial control bus is a high-speed optical fiber line.

Technical Field

The invention relates to a pulse mixed transmission method and a pulse mixed transmission system of an excitation system, and belongs to the technical field of generator excitation systems.

Background

In a common generator excitation system, an excitation adjusting device controls a silicon controlled rectifier bridge in a power cabinet to work, and alternating current of an excitation power supply is rectified into direct current to be output to an excitation winding of a generator rotor so as to provide excitation current required by the operation of a generator. At present, an excitation adjusting device mainly has two technical schemes for controlling a rectifier bridge of a power cabinet:

1. the pulse signal cable is connected, a synchronous signal is acquired by an excitation adjusting device, a pulse amplification module in the device generates a pulse signal after conditioning and phase shifting and transmits the pulse signal to a power cabinet through a multi-core shielded cable, the specification of the pulse signal is generally DC 24V pulse, and the pulse signal can directly drive a pulse transformer in the power cabinet to generate trigger pulse required by the operation of a silicon controlled rectifier bridge;

2. the field communication bus is connected, a local controller is installed on each power cabinet, a special communication module is configured, and control instructions such as a trigger angle, a pulse on-off state and the like sent by the excitation adjusting device are received through the field communication bus. Meanwhile, a local controller of the power cabinet is required to acquire a synchronous signal, and a corresponding phase-shifting trigger pulse is generated according to the synchronous signal and the trigger angle to drive the silicon controlled rectifier bridge to work.

However, the field environment of the power cabinet is often severe when the excitation system operates, and the power cabinet is easily affected by vibration, noise and dust, and the electromagnetic environment is complex. If the excitation adjusting device and the power cabinet rectifier bridge are connected by adopting a pulse signal cable, signal attenuation and electromagnetic interference of a field environment are easily generated, the trigger work of the silicon controlled rectifier bridge is influenced, and the reliability of an excitation system is reduced; if the field communication bus is adopted for connection, a local controller is required to be installed on each power cabinet to take charge of communication and synchronous signal acquisition, so that the device cost and debugging difficulty of the power cabinet are increased, and the engineering application cost is increased.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and provides a pulse mixed transmission method and a pulse mixed transmission system for an excitation system, which effectively reduce the signal attenuation and electromagnetic interference influence brought by the field environment and improve the running stability of a generator.

In order to achieve the purpose, the invention is realized by adopting the following technical scheme:

in a first aspect, the present invention provides a pulse hybrid transmission method suitable for an excitation system power cabinet, including:

combining and setting the control data message signal corresponding to a single rectifying branch with the trigger pulse signal in sequence;

transmitting the combined signals corresponding to all the rectification branches through a serial control bus according to a power cabinet rectifier bridge trigger pulse time sequence;

the control data message corresponding to a single rectification branch comprises feature codes, and different feature codes represent the rectification branches corresponding to the trigger pulse signals combined with the control data message.

The pulse mixed transmission method can be suitable for being executed by an excitation adjusting device, and the other end of the serial control bus is used for receiving a corresponding serial message by a power cabinet controller so as to execute the driving control of a rectifier bridge of the power cabinet.

Further, the method also comprises the steps of transmitting a pulse blocking message or a pulse train triggering message through a serial control bus, wherein the pulse blocking message comprises a feature code corresponding to a pulse blocking instruction; the pulse train trigger message includes a feature code corresponding to the pulse train trigger instruction.

Further, the bit width of the characteristic code is set to be 3 bits, and 000 bits correspond to a pulse blocking instruction; 100. 010, 001, 011, 101 and 110 respectively correspond to different rectifying branches of the rectifying bridge of the power cabinet; 111 corresponds to a burst firing command.

Optionally, in the combined signal, the trigger pulse width is 1/32 periods of the excitation power signal period. For example, for an excitation power frequency of 50Hz, a period of 20ms, a trigger pulse width of 625us, corresponding to 11.25 ° for 1 period of 360 °. If a common optical fiber line with 100M transmission rate is adopted, the time occupied by the added serial data message and the hardware analysis message can be controlled within 1us (0.018 degrees) at most, and the influence on the pulse angle and the pulse width is in a reasonable range.

In a second aspect, the present invention provides a method for controlling a rectifier bridge of an excitation system power cabinet, including:

receiving a message pulse sequence transmitted through a serial control bus, wherein the message pulse sequence comprises a plurality of branch pulses arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal corresponding to a single rectifier branch with a trigger pulse signal, the control data message corresponding to the single rectifier branch comprises feature codes, and different feature codes represent rectifier branches corresponding to the trigger pulse signals combined with the control data messages;

sequentially acquiring and analyzing each branch pulse in the message pulse sequence to obtain a feature code for controlling a data message signal in the branch pulse and a corresponding rectification branch;

and acquiring a trigger pulse signal in the branch pulse, and generating a driving pulse of a corresponding rectifying branch in the rectifier bridge of the power cabinet according to the rectifying branch corresponding to the feature code and the receiving time and the pulse width of the trigger pulse signal.

The rectifier bridge control method can be suitable for being executed by a power cabinet controller, and a message pulse sequence obtained from a serial communication bus comes from an excitation adjusting device.

Further, the method also comprises the step of judging that the communication of the serial control bus is interrupted and outputting a communication fault signal in response to the fact that the message is not received within the set time length.

Further, the method further comprises: receiving a pulse blocking message or a pulse train triggering message transmitted through a serial control bus, analyzing to obtain a feature code, and according to the feature code: responding to the received pulse blocking message, executing a pulse blocking instruction, and stopping the output of the driving pulses of all the rectifying branches; and responding to the received pulse train trigger message, executing a pulse train sending instruction, and sending continuous trigger pulses to all the rectifying branches.

In a third aspect, the invention provides a pulse hybrid transmission system of an excitation system, which comprises an excitation adjusting device and a power cabinet, wherein the excitation adjusting device and the power cabinet are connected through a serial control bus; the power cabinet comprises a power cabinet controller and a power cabinet rectifier bridge;

the excitation adjusting device transmits a message pulse sequence to the power cabinet controller through the serial control bus; the message pulse sequence comprises a plurality of branch pulses which are arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal and a trigger pulse signal of a corresponding single rectifying branch, the control data message corresponding to the single rectifying branch comprises feature codes, and different feature codes represent rectifying branches corresponding to the trigger pulse signals combined with the control data message;

and the power cabinet controller receives the message pulse sequence, acquires the branch pulse, the feature code for controlling the data message signal in the branch pulse, the corresponding rectification branch and the trigger pulse signal in the branch pulse, and generates the driving pulse of the corresponding rectification branch in the power cabinet rectifier bridge according to the receiving time and the pulse width of the rectification branch corresponding to the feature code and the trigger pulse signal.

Further, the pulse sequence of the message transmitted to the power cabinet controller by the excitation regulating device further comprises a pulse blocking message or a pulse sequence triggering message, wherein the pulse blocking message comprises a feature code corresponding to a pulse blocking instruction; the pulse train trigger message comprises a feature code corresponding to the pulse train trigger instruction;

the power cabinet controller stops the output of the driving pulses of all the rectifying branches in response to the received pulse blocking message; and the power cabinet controller responds to the received pulse train trigger message, executes the pulse train to send out an instruction and sends out continuous trigger pulses to all the rectifying branches. Each power cabinet configuration only needs to be configured with one serial control line, the excitation regulating device sends out a mixed transmission message, and the control of 6 branch circuit controllable silicon of the rectifier bridge of the power cabinet is combined into one string of messages.

Further, the serial control bus is a high-speed optical fiber line.

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

according to the invention, each power cabinet is provided with a serial control line, and the control data message is matched with the trigger pulse time sequence for hybrid transmission, so that the working control of the silicon controlled rectifier bridge of the power cabinet is realized, the signal attenuation and electromagnetic interference influence caused by the field environment can be effectively reduced, and meanwhile, a local controller acquisition synchronous signal module is not required to be installed on each power cabinet, so that the debugging step and the engineering cost are simplified, the reliability of an excitation system is ensured, and the running stability of the generator is further improved.

Drawings

FIG. 1 is a work flow of a power cabinet controller;

FIG. 2 is a pulse mixing transmission device of an excitation system;

FIG. 3 is a schematic diagram of adding a serial data message;

fig. 4 is a schematic diagram of a three-phase fully controlled rectifier bridge.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Example 1

As shown in fig. 4, most of the existing conventional rectifier bridges of the power cabinet of the excitation system are three-phase fully-controlled rectifier bridges, that is, the rectifier bridges of the power cabinet are composed of 6 controllable silicon, and are respectively six branches of + a, -a, + B, -B, + C, and-C, and rectify a three-phase ac excitation power supply into a dc, and apply the dc to a rotor excitation winding of a generator.

In this embodiment, a pulse hybrid transmission system of an excitation system is described, as shown in fig. 2, the system includes an excitation adjusting device and a power cabinet, and the excitation adjusting device and the power cabinet are connected by a serial control bus; the power cabinet comprises a power cabinet controller and a power cabinet rectifier bridge; the serial control bus is preferably a high speed fiber optic line.

The excitation adjusting device transmits a message pulse sequence to the power cabinet controller through the serial control bus; the message pulse sequence comprises a plurality of branch pulses which are arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal corresponding to a single rectifier branch with a trigger pulse signal, the control data message corresponding to the single rectifier branch comprises feature codes, and different feature codes represent rectifier branches corresponding to the trigger pulse signals combined with the control data messages;

the power cabinet controller receives the message pulse sequence, obtains the branch pulse, the feature code of the control data message signal in the branch pulse, the corresponding rectification branch and the trigger pulse signal in the branch pulse, and generates the driving pulse of the corresponding rectification branch in the power cabinet rectifier bridge according to the receiving time and the pulse width of the rectification branch corresponding to the feature code and the trigger pulse signal.

Further, the pulse sequence of the message transmitted to the power cabinet controller by the excitation regulating device further comprises a pulse blocking message or a pulse sequence triggering message, and the pulse blocking message comprises a feature code corresponding to a pulse blocking instruction; the pulse train trigger message includes a feature code corresponding to the pulse train trigger instruction.

In this embodiment, the bit width of the feature code in the control data packet is set to 3 bits, 000 corresponding to the pulse blocking; 100. 010, 001, 011, 101 and 110 respectively correspond to different rectifying branches of the rectifying bridge of the power cabinet; 111 corresponds to a burst firing command. And certainly not limited to other distinguishing forms of feature codes.

Specifically, when the feature code received by the power controller is 000, a pulse blocking function is executed, the emission of trigger pulses of all current branches is stopped subsequently, and the output of a rectifier bridge of the power cabinet is stopped; when the feature code is 100, 010, 001, 011, 101, 110, the power controller correspondingly sends out trigger pulses of a corresponding branch in "+ A, + B, + C, -A, -B, -C"; when the feature code is 111, the power controller executes a pulse train sending function, and then sends continuous trigger pulses to all the branches at the same time, so that the output of the rectifier bridge of the power cabinet when the voltage of the alternating current side is lower is realized.

In the combined signal, the trigger pulse width is 1/32 cycles of the excitation power supply signal cycle. For example, for an excitation power frequency of 50Hz, a period of 20ms, a trigger pulse width of 625us, corresponding to 11.25 ° for 1 period of 360 °. If a common optical fiber line with 100M transmission rate is adopted, the time occupied by the added serial data message and the hardware analysis message can be controlled within 1us (0.018 degrees) at most, and the influence on the pulse angle and the pulse width is in a reasonable range.

Example 2

Based on the same inventive concept as embodiment 1, this embodiment introduces a pulse mixing transmission method suitable for an excitation system power cabinet, which can be executed by an excitation adjusting device in embodiment 1, and the method includes:

combining and setting the control data message signal corresponding to a single rectifying branch with the trigger pulse signal in sequence;

transmitting the combined signals corresponding to all the rectification branches through a serial control bus according to a power cabinet rectifier bridge trigger pulse time sequence;

the control data message corresponding to a single rectification branch comprises feature codes, and different feature codes represent the rectification branches corresponding to the trigger pulse signals combined with the control data message.

As shown in fig. 3, in the hybrid transmission, taking the + a pulse as an example, a control data packet is added before the + a pulse.

The method also comprises the steps of transmitting a pulse blocking message or a pulse train triggering message through the serial control bus, wherein the pulse blocking message comprises a feature code corresponding to a pulse blocking instruction; the pulse train trigger message includes a feature code corresponding to the pulse train trigger instruction.

The bit width of the feature code is set to be 3 bits, and 000 bits correspond to pulse blocking; 100. 010, 001, 011, 101 and 110 respectively correspond to different rectifying branches of the rectifying bridge of the power cabinet; 111 corresponds to a burst firing command.

In the combined signal, the trigger pulse width is 1/32 cycles of the excitation power supply signal cycle. For example, for an excitation power frequency of 50Hz, a period of 20ms, a trigger pulse width of 625us, corresponding to 11.25 ° for 1 period of 360 °.

Example 3

Based on the same inventive concept as embodiments 1 and 2, this embodiment introduces a rectifier bridge control method for an excitation system power cabinet, which is suitable for being executed by a power controller in embodiment 1, and as shown in fig. 1, the method includes:

receiving a message pulse sequence transmitted through a serial control bus, wherein the message pulse sequence comprises a plurality of branch pulses arranged according to a power cabinet rectifier bridge trigger pulse time sequence, each branch pulse is formed by sequentially combining a control data message signal corresponding to a single rectifier branch and a trigger pulse signal, the control data message corresponding to the single rectifier branch comprises feature codes, and different feature codes represent rectifier branches corresponding to the trigger pulse signals combined with the control data messages;

sequentially acquiring and analyzing each branch pulse in the message pulse sequence to obtain a feature code for controlling a data message signal in the branch pulse and a corresponding rectification branch;

and acquiring a trigger pulse signal in the branch pulse, and generating a driving pulse of a corresponding rectifying branch in the rectifier bridge of the power cabinet according to the rectifying branch corresponding to the feature code and the receiving time and the pulse width of the trigger pulse signal.

Specifically, if the feature code of the received data message is analyzed to be 000, the pulse blocking function is executed, the sending of the trigger pulses of all the branches is stopped, and the output of the rectifier bridge of the power cabinet is stopped; if the feature code is 100, 010, 001, 011, 101, 110, the trigger pulse of the corresponding branch in "+ A, + B, + C, -A, -B, -C" is correspondingly sent out; if the feature code is 111, executing a pulse train sending function, and subsequently sending continuous trigger pulses to all the branches at the same time to realize the output of the rectifier bridge of the power cabinet when the voltage at the alternating current side is lower.

In this embodiment, the method further includes: judging whether the communication state is normal or not in the process of receiving the message pulse sequence; the judgment basis is that whether message data transmitted by the serial communication bus is not received within a set time length, if so, the communication of the rectifier bridge of the power cabinet is considered to be interrupted, and at the moment, a communication fault signal can be output to exit the operation.

The invention provides a pulse hybrid transmission method and a pulse hybrid transmission system for an excitation system.

By using the method, signal attenuation and electromagnetic interference brought by the field environment can be effectively avoided, a local controller acquisition synchronous signal module does not need to be installed on each power cabinet, the debugging step and the engineering cost are simplified, the reliability of an excitation system is ensured, and the running stability of the generator is further improved.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.