阅读说明：本技术 一种垃圾电厂引风机变频与工频切换控制方法 (Frequency conversion and power frequency switching control method for induced draft fan of garbage power plant ) 是由 方子朝 张乃元 何信林 张文斌 张钢 李洲 雷阳 张灏 于 2020-12-08 设计创作，主要内容包括：本发明公开了一种垃圾电厂引风机变频与工频切换控制方法,该方法基于的风机高压变频与工频切换系统包括包含五个模块,分别是工频电源进线模块、高压变频进线开关模块、高压变频模块、高压变频出线开关模块以及工频旁路开关模块；该方法包括：高压变频器严重故障工况变频切工频控制模式：高压变频器运行正常工况变频切工频控制模式：以及,高压变频器运行正常工况工频切变频控制模式。本发明在满足机组安全稳定运行同时,保证了垃圾能够及时得到处理的民生问题。(The invention discloses a frequency conversion and power frequency switching control method for a draught fan of a garbage power plant, wherein a high-voltage frequency conversion and power frequency switching system of the draught fan based on the method comprises five modules, namely a power frequency power supply incoming line module, a high-voltage frequency conversion incoming line switch module, a high-voltage frequency conversion outgoing line switch module and a power frequency bypass switch module; the method comprises the following steps: the working condition frequency conversion of the serious fault of the high-voltage frequency converter switches the power frequency control mode: the high-voltage frequency converter operates a normal working condition frequency conversion and power frequency switching control mode: and the high-voltage frequency converter operates a normal working condition power frequency switching frequency conversion control mode. The invention meets the requirement of safe and stable operation of the unit and simultaneously ensures the domestic problem that garbage can be treated in time.)

1. A frequency conversion and power frequency switching control method for a draught fan of a refuse power plant is characterized in that a high-voltage frequency conversion and power frequency switching system of the draught fan based on the method comprises five modules which are respectively a power frequency power supply inlet wire module, a high-voltage frequency conversion inlet wire switch module, a high-voltage frequency conversion outlet wire switch module and a power frequency bypass switch module, wherein one outlet wire of a power frequency power supply inlet wire module switch QF0 of the switching system is connected with an upper port of a high-voltage frequency conversion inlet wire switch module switch QF1, a lower port of the high-voltage frequency conversion inlet wire switch module switch QF1 is connected with an upper port of a high-voltage frequency conversion inlet wire switch module isolating switch QS1, a lower port of the high-voltage frequency conversion inlet wire switch module isolating switch QS1 is connected with an inlet wire end of the high-voltage frequency conversion module, an outlet wire end of the high-voltage frequency conversion module switch QF2, the lower port of a high-voltage frequency conversion outgoing switch module isolating switch QS1 is connected to an induced draft fan M; the other path of the outlet line of a power frequency power supply inlet module switch QF0 of the switching system is connected to the upper port of a power frequency bypass switch module QF3, and the lower port of the power frequency bypass switch module QF3 is connected to a draught fan M;

the method comprises the following steps:

the working condition frequency conversion of the serious fault of the high-voltage frequency converter switches the power frequency control mode:

the high-voltage frequency converter operates a normal working condition frequency conversion and power frequency switching control mode: and the number of the first and second groups,

and the high-voltage frequency converter operates in a normal working condition power frequency switching frequency conversion control mode.

2. The method for controlling the switching between the frequency conversion and the power frequency of the induced draft fan of the refuse power plant according to claim 1,

the method comprises the following steps that a high-voltage frequency converter is in operation and has serious faults under the condition of serious faults, the high-voltage frequency converter cannot be recovered after self-checking, and the DCS judges that the high-voltage frequency converter has the fault condition frequency conversion switching power frequency control mode, and on one hand, the DCS immediately sends a tripping instruction for tripping an incoming line switch QF1 and an outgoing line switch QF2 of the high-voltage frequency converter; on the other hand, a guide vane adjusting instruction is sent out at the same time, and after the DCS receives a feedback signal that the air door is adjusted to a proper position, the DCS immediately sends a power-on frequency bypass switch QF3 instruction; when the DCS sends a guide vane adjusting instruction T1 and delays, the DCS still does not receive a feedback signal of the air door adjusted to a proper position, the DCS still sends a power frequency bypass switch QF3 instruction, when the DCS sends instructions T2 of a trip high-voltage frequency converter incoming line switch QF1 and a trip high-voltage frequency converter outgoing line switch QF2, the DCS judges that the frequency conversion switching work of the serious fault working condition of the high-voltage frequency converter fails and sends a trip power frequency incoming line power module switch QF0 if the DCS does not detect the switching-on state of the power frequency bypass switch QF 3; if the power frequency bypass switch QF3 is detected to be in a closing state, the frequency conversion and frequency cutting of the high-voltage frequency converter are judged to be successful under the normal operating condition.

3. The method for controlling switching between frequency conversion and power frequency of the induced draft fan of the refuse power plant according to claim 2, wherein T1 is a delay opening degree from the cold test guide vane running to the frequency converter running to 50 Hz.

4. The method for controlling switching between frequency conversion and power frequency of the induced draft fan of the refuse power plant according to claim 3, wherein T2> T1.

5. The method for controlling the switching between the frequency conversion and the power frequency of the induced draft fan of the refuse power plant according to claim 1,

the high-voltage frequency converter normal operation working condition frequency conversion switching power frequency control mode indicates that the high-voltage frequency converter normally operates, on one hand, a DCS sends a given frequency adjustment instruction, on the other hand, the DCS adjusts a guide vane instruction, when the operation frequency of the high-voltage frequency converter of the induced draft fan is increased to be close to power frequency and stably operates, the DCS judges as a high-voltage frequency converter normal working condition frequency conversion switching power frequency control mode, the high-voltage frequency converter normal working condition frequency conversion switching locking condition is increased, the DCS sends a high-voltage frequency converter normal working condition frequency conversion switching power frequency instruction, a switch QF3 of a power frequency bypass switch module is switched on, meanwhile, a high-voltage frequency converter incoming line switch module switch QF1 and a high-voltage frequency converter outgoing line switch module switch QF2 trip, the high-voltage frequency converter normal working condition frequency conversion switching frequency is judged to be successful, and if the switch QF3 state, and at the moment, the frequency conversion and frequency switching failure of the high-voltage frequency converter under the normal operation condition is judged, and a power frequency tripping incoming switch QF0 instruction is sent out.

6. The method for controlling switching between frequency conversion and power frequency of the induced draft fan of the refuse power plant according to claim 5, wherein the switching locking condition is that 51Hz is more than or equal to F is more than or equal to 49 Hz.

7. The method for controlling switching between frequency conversion and power frequency of the induced draft fan of the refuse power plant according to claim 1, wherein the power frequency switching and frequency conversion control mode under the normal operation condition of the high-voltage inverter means that the high-voltage inverter is recovered from a fault state to a normal operation, and the control method for switching between the power frequency of the high-voltage inverter and the frequency conversion is realized while the induced draft fan is not stopped; on one hand, the DCS sends out ' adjustment of the given frequency of the high-voltage frequency converter to be 50Hz ', on the other hand, the DCS sends out ' adjustment guide vane instruction ', when the operation frequency of the high-voltage frequency converter of the induced draft fan is increased to be close to power frequency and stably operates, the DCS judges that ' the normal working condition power frequency switching frequency conversion control mode of the high-voltage frequency converter ', the switching locking condition of the power frequency shear frequency control mode of the normal working condition of the operation of the high-voltage frequency converter is increased, the DCS sends out ' power frequency switching frequency conversion command of the normal working condition of the operation of the high-voltage frequency converter, a switch QF3 of a power frequency bypass switch module trips, meanwhile, a high-voltage frequency converter incoming line switch module switch QF1 and a high-voltage frequency converter outgoing line switch QF2 are switched; if the switching-off state of QF3 is detected, the power frequency shear frequency failure of the high-voltage frequency converter under the normal operation condition is judged at the moment, and a power frequency inlet switch QF0 jumping instruction is issued.

8. The method for controlling switching between frequency conversion and power frequency of the induced draft fan of the refuse power plant as claimed in claim 7, wherein the switching locking condition is 51 Hz-F-49 Hz.

Technical Field

The invention belongs to the technical field of power plant induced draft fans, and particularly relates to a frequency conversion and power frequency switching control method for an induced draft fan of a garbage power plant.

Background

At present, the power of an induced draft fan is mainly divided into two modes of motor driving and steam turbine driving. In order to reduce the plant power consumption, the garbage power plant generally adopts variable frequency operation to the induced draft fan driven by the motor so as to achieve the purposes of energy conservation and consumption reduction.

The defects and shortcomings of the prior art are as follows:

considering that a high-voltage frequency converter is a complex system composed of power electronic devices, the high-voltage frequency converter is environment-friendly. Various faults are inevitable to occur due to device aging and the like. After the converter breaks down, easily cause the draught fan tripping operation on the one hand, not only influence the load, cause huge economic loss, threaten the safety and stability operation of unit even under the severe condition, on the other hand easily causes because the boiler is flame out the civilian problem that leads to rubbish can not in time be handled.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a frequency conversion and power frequency switching control method for a draught fan of a garbage power plant, aiming at solving the problem that the operation mode of the draught fan is switched from a frequency conversion mode to a power frequency mode under the condition that a high-voltage frequency converter of the draught fan has a serious accident, and ensuring the civil problem that garbage can be timely treated while meeting the safe and stable operation of a unit.

In order to achieve the purpose, the invention adopts the following technical scheme:

a frequency conversion and power frequency switching control method for a draught fan of a refuse power plant is based on a high-voltage frequency conversion and power frequency switching system of the draught fan, and comprises five modules which are a power frequency power supply inlet wire module, a high-voltage frequency conversion inlet wire switch module, a high-voltage frequency conversion outlet wire switch module and a power frequency bypass switch module respectively, wherein one path of an outlet wire of a power frequency power supply inlet wire module switch QF0 of the switching system is connected with an upper port of a high-voltage frequency conversion inlet wire switch module switch QF1, a lower port of a high-voltage frequency conversion inlet wire switch module switch QF1 is connected with an upper port of a high-voltage frequency conversion inlet wire switch module isolating switch QS1, a lower port of a high-voltage frequency conversion inlet wire switch module isolating switch QS1 is connected to an inlet wire end of the high-voltage frequency conversion module, an outlet wire end of the high-voltage frequency conversion module switch QF2 is connected to an, the lower port of a high-voltage frequency conversion outgoing switch module isolating switch QS1 is connected to an induced draft fan M; the other path of the outlet line of a power frequency power supply inlet module switch QF0 of the switching system is connected to the upper port of a power frequency bypass switch module QF3, and the lower port of the power frequency bypass switch module QF3 is connected to a draught fan M;

the method comprises the following steps:

the working condition frequency conversion of the serious fault of the high-voltage frequency converter switches the power frequency control mode:

the high-voltage frequency converter operates a normal working condition frequency conversion and power frequency switching control mode: and the number of the first and second groups,

and the high-voltage frequency converter operates in a normal working condition power frequency switching frequency conversion control mode.

The invention has the further improvement that the frequency conversion switching power frequency control mode of the serious fault working condition of the high-voltage frequency converter means that the running high-voltage frequency converter has serious fault and cannot be recovered after self-checking of the high-voltage frequency converter, and the DCS judges that the frequency conversion switching power frequency control mode of the fault working condition of the high-voltage frequency converter is ' tripping command ' for tripping the inlet switch QF1 and the outlet switch QF2 of the high-voltage frequency converter ' is sent out immediately on one hand; on the other hand, a guide vane adjusting instruction is sent out at the same time, and after the DCS receives a feedback signal that the air door is adjusted to a proper position, the DCS immediately sends a power-on frequency bypass switch QF3 instruction; when the DCS sends a guide vane adjusting instruction T1 and delays, the DCS still does not receive a feedback signal of the air door adjusted to a proper position, the DCS still sends a power frequency bypass switch QF3 instruction, when the DCS sends instructions T2 of a trip high-voltage frequency converter incoming line switch QF1 and a trip high-voltage frequency converter outgoing line switch QF2, the DCS judges that the frequency conversion switching work of the serious fault working condition of the high-voltage frequency converter fails and sends a trip power frequency incoming line power module switch QF0 if the DCS does not detect the switching-on state of the power frequency bypass switch QF 3; if the power frequency bypass switch QF3 is detected to be in a closing state, the frequency conversion and frequency cutting of the high-voltage frequency converter are judged to be successful under the normal operating condition.

The invention is further improved in that T1 is a delay opening degree of cold state test guide vane running to the frequency converter running to 50 Hz.

A further improvement of the invention is that T2> T1.

The invention is further improved in that the frequency conversion switching power frequency control mode of the normal operation condition of the high-voltage frequency converter means that the high-voltage frequency converter normally operates, on one hand, the DCS sends a command for adjusting the given frequency to be 50Hz, on the other hand, when the operation frequency of the high-voltage frequency converter of the induced draft fan is increased to be close to the power frequency and stably operates, the DCS judges that the frequency conversion switching power frequency control mode of the normal operation condition of the high-voltage frequency converter is' normal operation condition, the locking condition of the frequency conversion switching power frequency control mode switching of the normal operation condition of the high-voltage frequency converter is increased, the DCS sends a frequency conversion switching power frequency command of the normal operation condition of the high-voltage frequency converter, the switch QF3 of the power frequency bypass switch module is switched on, meanwhile, the switch QF1 of the high-voltage frequency converter and the switch QF2 of the high-voltage frequency converter trip, at the moment, the frequency converter, and at the moment, the frequency conversion and frequency switching failure of the high-voltage frequency converter under the normal operation condition is judged, and a power frequency tripping incoming switch QF0 instruction is sent out.

The invention has the further improvement that the switching locking condition is that 51Hz is more than or equal to F is more than or equal to 49 Hz.

The invention has the further improvement that the power frequency switching and frequency conversion control mode under the normal operating condition of the high-voltage frequency converter refers to a control method for switching the power frequency of the high-voltage frequency converter to frequency conversion without stopping the induced draft fan when the high-voltage frequency converter is recovered from a fault state to a normal operation; on one hand, the DCS sends out ' adjustment of the given frequency of the high-voltage frequency converter to be 50Hz ', on the other hand, the DCS sends out ' adjustment guide vane instruction ', when the operation frequency of the high-voltage frequency converter of the induced draft fan is increased to be close to power frequency and stably operates, the DCS judges that ' the normal working condition power frequency switching frequency conversion control mode of the high-voltage frequency converter ', the switching locking condition of the power frequency shear frequency control mode of the normal working condition of the operation of the high-voltage frequency converter is increased, the DCS sends out ' power frequency switching frequency conversion command of the normal working condition of the operation of the high-voltage frequency converter, a switch QF3 of a power frequency bypass switch module trips, meanwhile, a high-voltage frequency converter incoming line switch module switch QF1 and a high-voltage frequency converter outgoing line switch QF2 are switched; if the switching-off state of QF3 is detected, the power frequency shear frequency failure of the high-voltage frequency converter under the normal operation condition is judged at the moment, and a power frequency inlet switch QF0 jumping instruction is issued.

The invention has the further improvement that the switching locking condition is that 51Hz is more than or equal to F is more than or equal to 49 Hz.

The invention has at least the following beneficial technical effects:

the method for controlling the frequency conversion and power frequency switching of the induced draft fan of the garbage power plant solves the problem that the operation mode of the induced draft fan is switched from a frequency conversion mode to a power frequency mode when a serious accident happens to the high-voltage frequency converter of the induced draft fan, and solves the civil problem that garbage can be timely treated while the safe and stable operation of the unit is met.

Drawings

Fig. 1 is a topological structure diagram of the frequency conversion and power frequency switching system of the induced draft fan, and the high-voltage frequency conversion and power frequency switching system of the induced draft fan comprises five modules, namely a power frequency power supply incoming line module, a high-voltage frequency conversion incoming line switch module, a high-voltage frequency conversion outgoing line switch module and a power frequency bypass switch module.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. A

Referring to fig. 1, the method for controlling switching between frequency conversion and power frequency of an induced draft fan of a refuse power plant provided by the invention comprises the following steps: mode 1, a high-voltage frequency converter serious fault working condition frequency conversion power frequency switching control mode; in the mode 2, the high-voltage frequency converter operates a normal working condition frequency conversion power frequency switching control mode; and in the mode 3, the high-voltage frequency converter operates in a normal working condition power frequency switching frequency conversion control mode.

The control method of the normal operation mode of the high-voltage frequency converter refers to a) a manual switching frequency conversion incoming line module isolating switch QS1 and a frequency conversion outgoing line module isolating switch QS 2; b) a high-voltage variable-frequency outgoing switch QF2 and a high-voltage variable-frequency incoming switch QF1 are closed; c) a combined power frequency power supply incoming line module switch QF 0; d) and giving the corresponding frequency of the frequency converter.

Mode 1 high-voltage inverter serious fault working condition frequency conversion power frequency switching control mode.

The high-voltage frequency converter serious fault working condition frequency conversion switching power frequency control mode indicates that the running high-voltage frequency converter has serious fault and cannot be recovered after self-checking of the high-voltage frequency converter, and the DCS judges that the high-voltage frequency converter fault working condition frequency conversion switching power frequency control mode is ' on one hand, the DCS immediately sends ' tripping instructions for tripping on the high-voltage frequency converter incoming line switch module switch QF1 and tripping on the high-voltage frequency converter outgoing line switch module switch QF2 '; and on the other hand, a guide vane adjusting instruction is sent out simultaneously, and after the DCS receives a feedback signal that the air door is adjusted to a proper position, the DCS immediately sends an on-line frequency bypass switch module switch QF3 instruction. When the DCS sends a 'guide vane adjusting instruction' T1 (when a cold test guide vane runs to a frequency converter and runs to 50Hz delay opening degree), the DCS still sends a 'combined power frequency bypass switch module switch QF 3' instruction without receiving a feedback signal that the air door is adjusted to a proper position, and when the DCS sends a 'tripping high-voltage frequency converter incoming line switch module switch QF1 and tripping high-voltage frequency converter outgoing line switch module switch QF 2' instruction T2(T2> T1) delay, if the DCS does not detect the switching-on state of the power frequency bypass switch QF3, the frequency conversion switching operation failure of the serious fault working condition of the high-voltage frequency converter is judged at the moment, and the switching operation of the power frequency tripping incoming line power module switch QF0 is sent; if the power frequency bypass switch module switch QF3 switching-on state is detected, the frequency conversion and the frequency switching success of the high-voltage frequency converter under the normal operation condition are judged at the moment.

Mode 2 the high voltage inverter operates a normal operating mode frequency conversion power frequency switching control mode.

The high-voltage frequency converter normal operation working condition frequency conversion switching power frequency control mode indicates that the high-voltage frequency converter normally operates, on one hand, a DCS sends a given frequency regulation instruction, on the other hand, the DCS regulates a guide vane, when the operation frequency of the high-voltage frequency converter of a draught fan is increased to be close to power frequency and stably operates, the DCS judges as a high-voltage frequency converter normal working condition frequency conversion switching power frequency control mode, the switching locking condition of the high-voltage frequency converter normal working condition frequency conversion switching power frequency control mode is increased (51Hz is more than or equal to F is more than or equal to 49Hz), the DCS sends a high-voltage frequency converter normal working condition frequency conversion switching power frequency instruction, a switch QF3 of a power frequency bypass switch module, and simultaneously, a high-voltage incoming line switch module switch QF1 and a high-voltage frequency converter outgoing line switch module switch QF2 trip, at the moment, the high-voltage frequency converter normal working condition frequency converter operation frequency, and at the moment, the frequency conversion and frequency switching failure of the high-voltage frequency converter under the normal operation condition is judged, and a power frequency tripping incoming switch QF0 instruction is sent out. Mode 3 high-voltage frequency converter normal operation working condition power frequency shear frequency control mode

Mode 3 Power frequency shear frequency control mode for normal operating condition of high-voltage frequency converter

The power frequency switching and frequency conversion control mode of the high-voltage frequency converter under the normal operation condition refers to a control method for switching the power frequency of the high-voltage frequency converter to frequency conversion when the high-voltage frequency converter is recovered to normal operation from a fault state and a draught fan is not stopped. The method comprises the steps that on one hand, a DCS sends out ' adjustment of the given frequency of a high-voltage frequency converter to be 50Hz ', on the other hand, the DCS sends out ' adjustment of a guide vane instruction ', when the operation frequency of the high-voltage frequency converter of a draught fan is increased to be close to power frequency and stably operates, the DCS judges that ' normal working condition power frequency switching frequency conversion control mode of the high-voltage frequency converter ', the switching locking condition of the normal working condition power frequency switching frequency conversion control mode of the operation of the high-voltage frequency converter is increased (51Hz is larger than or equal to F is larger than or equal to 49Hz), the DCS sends out ' power frequency switching frequency conversion command of the normal working condition power frequency of the operation of the high-voltage frequency converter, a switch QF3 of a power frequency bypass switch module trips, meanwhile, a switch on a high-voltage frequency converter incoming line switch module switch. If the switching-off state of QF3 is detected, the power frequency shear frequency failure of the high-voltage frequency converter under the normal operation condition is judged at the moment, and a power frequency inlet switch QF0 jumping instruction is issued.