Control circuit for slaked lime variable-frequency feeding motor

Abstract

The control circuit comprises a power supply loop, a miniature circuit breaker, a frequency conversion control loop, a power frequency control loop, an alternating current contactor, an intermediate relay, a frequency conversion module, a frequency conversion feeding motor, a frequency conversion conversion control module and a conversion control switch. According to the utility model, on the premise of meeting all functions which can be realized by the original technical scheme, the shutdown risk caused by the fault of the frequency converter is greatly reduced, and the sulfur dioxide emission data is ensured to be stabilized within the national standard.

Description

[Technical field]

[0001] The utility model relates to the technical field of feeding motor control, in particular to the technical field of control circuits for slaked lime variable frequency feeding motors. [Background technology]

[0002] The slaked lime variable frequency feeding motor is an important part of the desulfurization system, mainly used to control the sulfur dioxide content in the flue gas. As the core equipment of dry desulfurization, the slaked lime variable frequency feeding motor mainly controls the feeding amount of slaked lime by controlling the frequency of the motor according to the sulfur dioxide emission data monitored by CEMS, and relies on the positive pressure of the Roots blower to transport it to the flue of the reaction tower to produce a chemical reaction with the sulfur dioxide in the flue gas, thereby achieving the purpose of desulfurization. As an effective way to solve the quantitative feeding of slaked lime, the slaked lime variable frequency feeding motor has been widely used.

[0003] The existing control method of the variable frequency feeding motor of slaked lime is to set a local control box next to the machine, and control the inverter to adjust the motor speed automatically through the DCS given frequency signal.

[0004] The control method of the above-mentioned feeding motor is single. When the frequency converter fails, the feeding motor automatically trips and the system stops running. When the fault problem is complicated and cannot be eliminated in a short time, it will affect the environmental protection data of sulfur dioxide emissions and cause serious consequences. [Contents of the utility model]

[0005] The purpose of the utility model is to solve the problems in the prior art and to propose a control circuit for a variable frequency feeding motor for slaked lime. On the premise of meeting all the functions that can be achieved by the original technical solution, the risk of downtime caused by frequency converter failure can be greatly reduced, and the sulfur dioxide emission data can be ensured to be stable within the national standard.

[0006] To achieve the above-mentioned purpose, the utility model proposes a control circuit for a variable frequency feeding motor of slaked lime, including a power supply circuit, a miniature circuit breaker, a variable frequency control circuit, an industrial frequency control circuit, an AC contactor, an intermediate relay, a variable frequency module, a variable frequency feeding motor, a variable frequency conversion control module and a conversion control switch, wherein the output end of the power supply circuit is respectively connected to the variable frequency control circuit and the industrial frequency control circuit through a miniature circuit breaker, the variable frequency control circuit includes an AC contactor, an intermediate relay, a variable frequency module and a variable frequency feeding motor, and the miniature circuit breaker is respectively connected to the intermediate relay through an AC contactor The intermediate relay and the frequency converter are respectively connected to the variable frequency feeding motor, the industrial frequency control circuit includes an AC contactor, an intermediate relay and a variable frequency feeding motor, the miniature circuit breaker is connected to the intermediate relay through the AC contactor, the intermediate relay is connected to the variable frequency feeding motor, the variable frequency control circuit and the industrial frequency control circuit are connected to the variable frequency conversion control module, a conversion control switch is connected in the variable frequency conversion control module, the conversion control switch is connected to the variable frequency feeding motor, and a fixed frequency regulation circuit and a variable frequency regulation circuit are arranged in the conversion control switch.

[0007] Preferably, a fuse is provided in series between the frequency conversion control circuit and the industrial frequency control circuit and the frequency conversion control module.

[0008] Preferably, the variable frequency control circuit and the industrial frequency control circuit are arranged in parallel, and the variable frequency conversion control module is connected to the variable frequency control circuit and the industrial frequency control circuit respectively through an AC contactor.

[0009] Preferably, a manual motor frequency adjustment module and an automatic motor frequency adjustment module are provided in the frequency conversion control module.

[0010] Preferably, the variable frequency conversion control module is provided with corresponding working indicator lights for the variable frequency control circuit and the industrial frequency control circuit.

[0011] Preferably, the frequency conversion control module is provided with an audible and visual alarm.

[0012] Beneficial effects of the utility model: the utility model combines a power supply circuit, a miniature circuit breaker, a frequency conversion control circuit, an industrial frequency control circuit, an AC contactor, an intermediate relay, a frequency conversion module, a frequency conversion feeding motor, a frequency conversion conversion control module and a conversion control switch, and after experimental optimization, adopts the principle that one frequency converter corresponds to one frequency conversion feeding motor. The control of the frequency conversion feeding motor is divided into two modes: local and remote. The first local mode: switch the conversion control switch to the fixed frequency adjustment circuit, start the manual motor frequency adjustment module in the frequency conversion control module, and adjust the frequency by the + and - buttons on the control panel to control the frequency of the frequency conversion motor; the second remote mode: switch the conversion control switch to the fixed frequency adjustment circuit, start the manual motor frequency adjustment module in the frequency conversion control module, and control the frequency of the frequency conversion motor by adjusting the frequency by the + and - buttons on the control panel; the second remote mode: switch the conversion control switch to the variable The frequency regulation loop, the automatic motor frequency regulation module in the frequency conversion control module is started, and the frequency of the frequency conversion motor is adjusted by the 4-20ma frequency signal given by the DCS. When the frequency converter sends a fault signal, the AC contactor of the frequency conversion control loop is automatically disconnected, and the AC contactor of the industrial frequency control loop is closed at the same time, and the industrial frequency operation mode is adopted; when the frequency converter fault is eliminated, the AC contactor of the industrial frequency control loop is automatically disconnected, and the AC contactor of the frequency conversion control loop is closed at the same time, and the frequency conversion operation mode is adopted. Under the premise of meeting all the functions that can be achieved by the original technical solution, the risk of shutdown caused by frequency converter fault can be reduced, and the sulfur dioxide emission data can be ensured to be stable within the national standard.

[0013] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0014] Figure 1 This is the principle of the control circuit of the utility model for the variable frequency feeding motor of slaked lime Figure 1 ;

[0015] Figure 2 This is the principle of the control circuit of the utility model for the variable frequency feeding motor of slaked lime Figure 2 ;

[0016] Figure 3 This is the principle of the control circuit of the utility model for the variable frequency feeding motor of slaked lime Figure 3 . [Specific implementation method]

[0017] See also Figure 1 , Figure 2 and Figure 3The utility model is used for the control circuit of the variable frequency feeding motor of slaked lime, including a power supply circuit, a miniature circuit breaker, a variable frequency control circuit, a power frequency control circuit, an AC contactor, an intermediate relay, a frequency conversion module, a variable frequency feeding motor, a frequency conversion control module and a conversion control switch. The output end of the power supply circuit is respectively connected to the variable frequency control circuit and the power frequency control circuit through a miniature circuit breaker. The variable frequency control circuit includes an AC contactor, an intermediate relay, a frequency conversion module and a variable frequency feeding motor. The miniature circuit breaker is respectively connected to the intermediate relay and the frequency converter through an AC contactor. The intermediate relay and the frequency converter are respectively connected to the variable frequency feeding motor, the industrial frequency control circuit includes an AC contactor, an intermediate relay and a variable frequency feeding motor, the miniature circuit breaker is connected to the intermediate relay through the AC contactor, the intermediate relay is connected to the variable frequency feeding motor, the variable frequency control circuit and the industrial frequency control circuit are connected to the variable frequency conversion control module, a conversion control switch is connected in the variable frequency conversion control module, the conversion control switch is connected to the variable frequency feeding motor, and a fixed frequency regulation circuit and a variable frequency regulation circuit are arranged in the conversion control switch.

[0018] Preferably, a fuse is provided in series between the frequency conversion control circuit and the industrial frequency control circuit and the frequency conversion control module.

[0019] Preferably, the variable frequency control circuit and the industrial frequency control circuit are arranged in parallel, and the variable frequency conversion control module is connected to the variable frequency control circuit and the industrial frequency control circuit respectively through an AC contactor.

[0020] Preferably, a manual motor frequency adjustment module and an automatic motor frequency adjustment module are provided in the frequency conversion control module.

[0021] Preferably, the variable frequency conversion control module is provided with corresponding working indicator lights for the variable frequency control circuit and the industrial frequency control circuit.

[0022] Preferably, the frequency conversion control module is provided with an audible and visual alarm.

[0023] The utility model combines a power supply circuit, a miniature circuit breaker, a frequency conversion control circuit, an industrial frequency control circuit, an AC contactor, an intermediate relay, a frequency conversion module, a frequency conversion feeding motor, a frequency conversion conversion control module and a conversion control switch together, and after experimental optimization, adopts the principle that one frequency converter corresponds to one frequency conversion feeding motor. The control of the frequency conversion feeding motor is divided into two modes: local and remote. The first local mode is to switch the conversion control switch to a fixed frequency regulation circuit, start the manual motor frequency regulation module in the frequency conversion control module, and adjust the frequency by the + and - buttons on the control panel to control the frequency of the frequency conversion motor; the second remote mode is to switch the conversion control switch to the frequency conversion regulation circuit. The automatic motor frequency adjustment module in the frequency conversion control module is started, and the frequency of the frequency conversion motor is adjusted by the 4-20ma frequency signal given by the DCS. When the frequency converter sends a fault signal, the AC contactor of the frequency conversion control circuit is automatically disconnected, and the AC contactor of the industrial frequency control circuit is closed at the same time, and the industrial frequency operation mode is adopted; when the frequency converter fault is eliminated, the AC contactor of the industrial frequency control circuit is automatically disconnected, and the AC contactor of the frequency conversion control circuit is closed at the same time, and the frequency conversion operation mode is adopted. On the premise of meeting all the functions that can be achieved by the original technical solution, the risk of shutdown caused by frequency converter failure can be reduced, ensuring that the sulfur dioxide emission data is stable within the national standard.

[0024] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention falls within the protection scope of the present invention.

Claims

1. The control circuit for the variable frequency feeding motor of slaked lime is characterized by: It includes a power supply circuit, a miniature circuit breaker, a frequency conversion control circuit, an industrial frequency control circuit, an AC contactor, an intermediate relay, a frequency conversion module, a frequency conversion feeding motor, a frequency conversion conversion control module and a conversion control switch. The output end of the power supply circuit is respectively connected to the frequency conversion control circuit and the industrial frequency control circuit through the miniature circuit breaker. The frequency conversion control circuit includes an AC contactor, an intermediate relay, a frequency conversion module and a frequency conversion feeding motor. The miniature circuit breaker is respectively connected to the intermediate relay and the frequency converter through the AC contactor. The intermediate relay and the frequency converter are respectively connected to the frequency conversion feeding motor. The industrial frequency control circuit includes an AC contactor, an intermediate relay and a frequency conversion feeding motor. The miniature circuit breaker is connected to the intermediate relay through the AC contactor. The intermediate relay is connected to the frequency conversion feeding motor. The frequency conversion control circuit and the industrial frequency control circuit are connected to the frequency conversion control module. The frequency conversion conversion control module is connected with a conversion control switch. The conversion control switch is connected to the frequency conversion feeding motor. The conversion control switch is provided with a fixed frequency regulation circuit and a frequency conversion regulation circuit.

2. The control circuit for the variable frequency feeding motor of slaked lime according to claim 1, characterized in that: A fuse is arranged in series between the frequency conversion control circuit, the industrial frequency control circuit and the frequency conversion control module.

3. The control circuit for the variable frequency feeding motor of slaked lime according to claim 1, characterized in that: The variable frequency control circuit and the industrial frequency control circuit are arranged in parallel, and the variable frequency conversion control module is connected to the variable frequency control circuit and the industrial frequency control circuit respectively through an AC contactor.

4. The control circuit for the variable frequency feeding motor of slaked lime according to claim 1, characterized in that: The frequency conversion control module is provided with a manual motor frequency adjustment module and an automatic motor frequency adjustment module.

5. The control circuit for the variable frequency feeding motor of slaked lime according to claim 1, characterized in that: The variable frequency conversion control module is provided with corresponding working indicator lights for the variable frequency control circuit and the industrial frequency control circuit.

6. The control circuit for the variable frequency feeding motor of slaked lime according to claim 1, characterized in that: The frequency conversion control module is provided with an audible and visual alarm.

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