CN101615873A - Frequency relay - Google Patents

Frequency relay Download PDF

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CN101615873A
CN101615873A CN200910012713A CN200910012713A CN101615873A CN 101615873 A CN101615873 A CN 101615873A CN 200910012713 A CN200910012713 A CN 200910012713A CN 200910012713 A CN200910012713 A CN 200910012713A CN 101615873 A CN101615873 A CN 101615873A
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frequency
relay
yzr
unit
motor rotor
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滕波
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Dalian Mh Times Technology Co ltd
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Dalian Mh Times Technology Co ltd
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Abstract

The invention discloses a frequency relay, which is characterized by comprising: the device comprises a frequency measuring circuit, a setting input unit, a relay unit and a control unit; after receiving the frequency signal of the YZR motor rotor sent back by the frequency measuring circuit, the frequency signal is converted into a specific frequency value to be compared with a frequency set value of the YZR motor rotor which is input by a setting input unit and enables the relay to operate, and when the frequency of the YZR motor rotor sent back by the frequency measuring circuit reaches the frequency set value, a control signal is sent to the relay unit to enable the relay in the relay unit to operate. Compared with the traditional control mode of a YZR type three-phase asynchronous winding type motor, the switching device provided by the invention has the advantage that the frequency relay is more accurately controlled than the time relay. In addition, the motor rotor resistance switching device is simple in structure, convenient to produce, low in cost and suitable for wide popularization in the field of motor rotor resistance switching.

Description

频率继电器 frequency relay

技术领域 technical field

本发明涉及一种YZR电动机转子电阻切换装置,尤其涉及一种采用频率继电器控制YZR电动机转子电阻切换的频率继电器。The invention relates to a YZR motor rotor resistance switching device, in particular to a frequency relay which uses a frequency relay to control the YZR motor rotor resistance switching.

背景技术 Background technique

在冶金机械设备、起重机等工业设备中,经常采用YZR型三相异步绕线式电动机。YZR型三相异步绕线式电动机在控制中需要在转子回路串入电阻,控制它的启动转矩,降低它的启动电流。而YZR型三相异步绕线式电动机需要全速运行时,需要切除转子回路中串入电阻,为了使整个起动过程中尽量保持较大的起动转矩,同时保证电动机电流不超标,一般在转子电阻切除时需要逐级进行切换,目前传统控制YZR型三相异步绕线式电动机转子电阻分级切除的是采用时间继电器的延时功能来实现的。由于时间继电器的延时时间是人为根据经验进行设定的,如图1所示为传统档位控制电阻切换的原理示意图,当S1档的时间继电器达到闭合时间时,认为电机达到S1档控制速度,档位S1闭合(相当于将S1短路掉),这样在电动机达到额定速度过程中依次切换S1、S2、S3和S4档位,以达到限定电机电流不超标。这种控制往往伴随着,设定的时间太短,电阻过早切除,使电动机切换电流超过其允许的最大电流,使电动机发热严重,电动机力矩会超过起动转矩,给机械机构很大的冲击,缩短整个传动链的寿命。设定的时间太长,电阻过晚切除,会使起动时间过长,不利于设备的使用和控制,降低了设备效率等问题,如图3所示电机转子切电阻时间继电器控制方式的控制效果图,实际电机在切换转子电阻的同时,承受的切换力矩与电流冲击是极不规律的(见ab,cd,ef,gh段),大多数情况是远大于电机额定值的。这是因为切换的条件是靠时间继电器控制,而实际中,时间继电器的调节是完全靠经验值的(见bc,de,fg段),不是十分准确。另外,由于在不同的运行方向,负载的作用不同,时间的调整就更困难,在下降方向,由于负载为加速力矩,电动机减速度大,设定时间短,有利于电动机,但在上升方向,由于负载为阻力力矩,电动机减速度小,设定时间短存在与阻力负载相同的情况,甚至更差。反之设定时间长,在上升方向可能合适,在下降方向由于时间长,就会造成电动机超速运行,为设备运行带来不安全。YZR three-phase asynchronous wound motors are often used in industrial equipment such as metallurgical machinery and cranes. In the control of YZR three-phase asynchronous wound motor, resistors need to be connected in series in the rotor circuit to control its starting torque and reduce its starting current. However, when the YZR three-phase asynchronous wound motor needs to run at full speed, it is necessary to cut off the resistance connected in series in the rotor circuit. Cutting needs to be switched step by step. At present, the traditional control of YZR three-phase asynchronous wound motor rotor resistance is cut off step by step by using the delay function of the time relay. Since the delay time of the time relay is set artificially based on experience, as shown in Figure 1, it is a schematic diagram of the principle of traditional gear control resistance switching. When the time relay of the S1 gear reaches the closing time, it is considered that the motor reaches the S1 gear control speed. , the gear position S1 is closed (equivalent to short-circuiting S1), so that the gears S1, S2, S3 and S4 are switched sequentially when the motor reaches the rated speed, so as to limit the motor current to not exceed the standard. This kind of control is often accompanied by the fact that the set time is too short, and the resistance is cut off prematurely, so that the switching current of the motor exceeds its allowable maximum current, causing the motor to heat up seriously, and the torque of the motor will exceed the starting torque, which will give a great impact to the mechanical mechanism. , shorten the life of the entire transmission chain. If the set time is too long and the resistance is cut off too late, the starting time will be too long, which is not conducive to the use and control of the equipment, and reduces the efficiency of the equipment. As shown in Figure 3, the control effect of the motor rotor cut resistance time relay control mode As shown in the figure, when the actual motor switches the rotor resistance, the switching torque and current impact it bears are extremely irregular (see paragraphs ab, cd, ef, gh), and in most cases it is far greater than the rated value of the motor. This is because the switching condition is controlled by the time relay, but in practice, the adjustment of the time relay is completely based on empirical values (see bc, de, fg paragraphs), which is not very accurate. In addition, due to the different action of the load in different running directions, the adjustment of the time is more difficult. In the downward direction, because the load is the acceleration torque, the deceleration of the motor is large, and the setting time is short, which is beneficial to the motor. But in the upward direction, Since the load is a resistance torque, the deceleration of the motor is small, and the setting time is short, which is the same as the resistance load, or even worse. Conversely, if the setting time is long, it may be suitable in the upward direction, but in the downward direction, the long time will cause the motor to run at an overspeed, which will bring unsafe operation to the equipment.

发明内容 Contents of the invention

本发明针对以上问题的提出,而研制一种在电机传统切电阻控制方式基础上,以电机转子频率为切电阻条件的控制装置。具体技术手段如下:In view of the above problems, the present invention develops a control device based on the traditional resistance cutting control mode of the motor, and takes the motor rotor frequency as the resistance cutting condition. The specific technical means are as follows:

一种频率继电器,其特征在于包括:A frequency relay is characterized in that it comprises:

频率测量电路,用于将输入的YZR电动机转子的频率信号进行滤波处理,将谐波分量、直流分量和干扰信号滤掉,并对还原后的信号进行放大处理后进行模/数转换将转换后的数字信号传输到控制单元中;The frequency measurement circuit is used to filter the input frequency signal of the YZR motor rotor, filter out the harmonic component, DC component and interference signal, and perform analog/digital conversion after the restored signal is amplified. The digital signal is transmitted to the control unit;

设置输入单元,用于向控制单元输入设定信号,即使继电器动作的YZR电动机转子的频率设定值;Set the input unit, which is used to input the setting signal to the control unit, that is, the frequency setting value of the rotor of the YZR motor whose relay operates;

继电器单元,在接收控制信号后进行相应的开点的闭合或闭点的打开,以实现将转子电阻连接或切掉;The relay unit, after receiving the control signal, closes the corresponding open point or opens the closed point to realize the connection or cut-off of the rotor resistance;

控制单元,在接收到频率测量电路传回的YZR电动机转子的频率信号后,将其转化为具体的频率数值,使其同设置输入单元输入的使继电器动作的YZR电动机转子的频率设定值进行比较,当频率测量电路传回的YZR电动机转子的频率达到上述频率设定值后,向继电器单元发出控制信号,使继电器单元中的继电器动作。The control unit, after receiving the frequency signal of the YZR motor rotor returned by the frequency measurement circuit, converts it into a specific frequency value, making it the same as the frequency setting value of the YZR motor rotor input by the setting input unit to make the relay act. In comparison, when the frequency of the YZR motor rotor returned by the frequency measurement circuit reaches the above-mentioned frequency setting value, a control signal is sent to the relay unit to make the relay in the relay unit act.

所述继电器单元中包括一个以上的继电器,相应的设置输入单元能够向控制单元输入一个以上的使继电器动作的YZR电动机转子的频率设定值。The relay unit includes more than one relay, and the corresponding setting input unit can input more than one frequency setting value of the rotor of the YZR motor to activate the relay to the control unit.

所述控制单元还通过检测YZR电动机转子的频率,以判断电动机的运行状态,当在相应档位,检测频率与实际设定值相差较远通过显示单元提示报警,并控制电源开关进行断电保护。The control unit also detects the frequency of the rotor of the YZR motor to judge the running state of the motor. When it is in the corresponding gear position, the detected frequency is far from the actual set value, and the display unit prompts an alarm, and controls the power switch for power-off protection .

本发明提供的频率继电器相对于YZR型三相异步绕线式电动机传统控制方式,频率继电器比时间继电器有更精确的控制,它通过对电动机转子频率(速度)进行检测,按照设定的频率进行相应的控制,这样无论何种情况,电阻切换点均为固定切换点。设定合适的切换点,即可加快电动机的速度响应时间,又不会使电动机承受过载和过流,极大的提高电动机的运行安全。频率继电器还可用于对电动机运行状态的保护,电动机在某种状态运行时,可以通过检测电动机转子频率来判断是否处于控制状态,当失控时可以提示报警,进行断电保护。另外,其结构简单、便于生产而且成本低廉适于在电动机转子电阻切换领域内广泛推广。Compared with the traditional control method of YZR type three-phase asynchronous winding motor, the frequency relay provided by the present invention has more precise control than the time relay. Corresponding control, so that no matter what the situation, the resistance switching point is a fixed switching point. Setting an appropriate switching point can speed up the speed response time of the motor without causing the motor to suffer from overload and overcurrent, which greatly improves the operation safety of the motor. The frequency relay can also be used to protect the running state of the motor. When the motor is running in a certain state, it can be judged whether it is in a controlled state by detecting the rotor frequency of the motor. When it is out of control, it can prompt an alarm and perform power-off protection. In addition, the structure is simple, easy to produce and low in cost, and is suitable for wide popularization in the field of motor rotor resistance switching.

附图说明 Description of drawings

图1为传统档位控制电阻切换的原理示意图;Figure 1 is a schematic diagram of the principle of traditional gear position control resistor switching;

图2为本发明所述切换装置的结构示意图;Fig. 2 is a schematic structural view of the switching device of the present invention;

图3为电机转子切电阻采用时间继电器控制方式的实现过程示意图;Fig. 3 is a schematic diagram of the implementation process of the motor rotor cutting resistance adopting the time relay control mode;

图4为本发明切换电阻为单电阻实施例的频率设定值的示意图;Fig. 4 is a schematic diagram of the frequency setting value of the embodiment of the switching resistance of the present invention being a single resistance;

图5为本发明切换电阻为单电阻切换装置实施例的结构示意图;Fig. 5 is a schematic structural diagram of an embodiment of a single-resistor switching device according to the present invention;

图6为本发明切换电阻为四个电阻实施例的频率设定值的示意图;Fig. 6 is a schematic diagram of the frequency setting value of the embodiment of the present invention where the switching resistance is four resistances;

图7为本发明切换电阻为四个电阻切换装置实施例的结构示意图;Fig. 7 is a schematic structural diagram of an embodiment of the switching resistance of the present invention with four resistance switching devices;

图8为电机转子切电阻采用时间继电器控制方式的实现过程示意图。Fig. 8 is a schematic diagram of the implementation process of using the time relay control method to cut the resistance of the motor rotor.

具体实施方式 Detailed ways

如图2所示为该频率继电器,包括:用于将输入的YZR电动机转子的频率信号进行滤波处理,将谐波分量、直流分量和干扰信号滤掉,并对还原后的信号进行放大处理后进行模/数转换将转换后的数字信号传输到控制单元中的频率测量电路;用于向控制单元输入设定信号,即使继电器动作的YZR电动机转子的频率设定值的设置输入单元;用于在接收控制信号后进行相应的开点的闭合或闭点的打开,以实现将转子电阻连接或切掉的继电器单元;以及在接收到频率测量电路传回的YZR电动机转子的频率信号后,将其转化为具体的频率数值,使其同设置输入单元输入的使继电器动作的YZR电动机转子的频率设定值进行比较,当频率测量电路传回的YZR电动机转子的频率达到上述频率设定值后,向继电器单元发出控制信号,使继电器单元中的继电器动作的控制单元。其中频率测量电路为隔离电路、滤波器和模/数转换器的集成电路;设置输入单元为外部输入装置,这里可以采用显示单元和设置输入单元一体的触摸屏来实现;继电器单元可以采用一个以上的继电器组,相应的设置输入单元也能够向控制单元输入一个以上的使继电器动作的YZR电动机转子的频率设定值,以控制电机电阻的不同档位的切换;控制单元为主控装置,可以是单片机和PLC等处理设备,以下实施例采用单片机来实现。As shown in Figure 2, the frequency relay includes: it is used to filter the input frequency signal of the YZR motor rotor, filter out the harmonic component, DC component and interference signal, and amplify the restored signal Carry out analog/digital conversion and transmit the converted digital signal to the frequency measurement circuit in the control unit; it is used to input the setting signal to the control unit, even if the relay operates the setting input unit of the frequency setting value of the YZR motor rotor; it is used for After receiving the control signal, the corresponding open point is closed or the closed point is opened to realize the relay unit that connects or cuts off the rotor resistance; and after receiving the frequency signal of the YZR motor rotor returned by the frequency measurement circuit, the It is converted into a specific frequency value, and compared with the frequency setting value of the YZR motor rotor input by the setting input unit to make the relay operate, when the frequency of the YZR motor rotor returned by the frequency measurement circuit reaches the above frequency setting value , A control unit that sends a control signal to the relay unit to make the relay in the relay unit act. The frequency measurement circuit is an integrated circuit of an isolation circuit, a filter and an analog/digital converter; the input unit is set as an external input device, which can be realized by using a touch screen integrated with a display unit and an input unit; the relay unit can use more than one For the relay group, the corresponding setting input unit can also input more than one frequency setting value of the YZR motor rotor that makes the relay act to the control unit to control the switching of different gears of the motor resistance; the control unit is the main control device, which can be Processing equipment such as single-chip microcomputer and PLC, the following embodiments adopt single-chip microcomputer to realize.

实施例1:如图4、图5所示,为电动机单档控制,进行测量时将频率测量电路的检测输入端连接到YZR型三相异步绕线式电动机转子端子上,通过频率测量电路中的滤波器滤掉输入电压信号中的谐波分量、直流分量和干扰信号,以还原出被测电源频率,在经过运放器和模/数转换处理后,交于单片机进行处理运算,最后计算出电源的频率同单片机根据设置输入单元输入的切换频率数值进行比对,当测得的频率到达设定值时,单片机会控制相应的继电器动作,完成档位切换的控制(如图4中所示,当频率达到a点时,控制器给继电器控制信号,相应继电器完成电阻的切换)。Embodiment 1: As shown in Figure 4 and Figure 5, it is a single-speed control of the motor. When measuring, connect the detection input end of the frequency measurement circuit to the rotor terminal of the YZR three-phase asynchronous wound motor, and pass through the frequency measurement circuit. The filter filters out the harmonic component, DC component and interference signal in the input voltage signal to restore the frequency of the power supply under test. After being processed by the op amp and analog/digital conversion, it is handed over to the single chip microcomputer for processing and calculation, and finally calculates The frequency of the power supply is compared with the switching frequency value input by the single-chip microcomputer according to the setting input unit. When the measured frequency reaches the set value, the single-chip computer controls the corresponding relay action to complete the control of gear switching (as shown in Figure 4 Indicates that when the frequency reaches point a, the controller sends a control signal to the relay, and the corresponding relay completes the switching of the resistance).

实施例2:如图6、图7和图8所示,其接线方式上和装置的设置上同实施例1相同,不同的是这里采用的是4个档位的切换控制,也就是继电器单元需要4个继电器完成4个档位的切换任务,相应的设置输入单元输入4个合适的切换点的频率值。如图6所示,这里通过设置输入单元向控制器输入了a、b、c和d 4个切换点,在使用该装置对YZR型三相异步绕线式电动机完成电阻切换是自动过程,如图8所示的切换转子电阻的情况,可以看出实际电机在切换转子电阻的同时,切换力矩与承受的电流是极其规律的(见ab,cd,ef,gh段)。通过参数设置,可以满足您的电机在转子电阻切换的时候,具有足够的力矩,同时电机转子电流也控制在适当的范围。Embodiment 2: As shown in Fig. 6, Fig. 7 and Fig. 8, its wiring mode and device setting are the same as those of Embodiment 1, the difference is that the switching control of 4 gears is used here, that is, the relay unit 4 relays are required to complete the switching tasks of 4 gears, and the input unit is set accordingly to input the frequency values of 4 suitable switching points. As shown in Figure 6, four switching points a, b, c and d are input to the controller by setting the input unit. It is an automatic process to complete the resistance switching of the YZR three-phase asynchronous wound motor with this device, as shown in In the case of switching rotor resistance shown in Figure 8, it can be seen that when the actual motor switches rotor resistance, the switching torque and the current it bears are extremely regular (see paragraphs ab, cd, ef, and gh). Through parameter setting, your motor can have sufficient torque when the rotor resistance is switched, and the motor rotor current can also be controlled within an appropriate range.

另外,控制单元还通过检测YZR电动机转子的频率,以判断电动机的运行状态,当在相应档位,检测频率与实际设定值相差较远通过显示单元提示报警,并控制电源开关进行断电保护。In addition, the control unit also detects the frequency of the rotor of the YZR motor to judge the running state of the motor. When it is in the corresponding gear, the detected frequency is far from the actual set value, and the display unit prompts an alarm, and controls the power switch for power-off protection. .

以上所述,仅为本发明较佳的具体实施方式,但本发明的保护范围并不局限于此,任何熟悉本技术领域的技术人员在本发明揭露的技术范围内,根据本发明的技术方案及其发明构思加以等同替换或改变,都应涵盖在本发明的保护范围之内。The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.

Claims (3)

1, a kind of frequency relay is characterized in that comprising:
Frequency measurement circuit, be used for will input the frequency signal of YZR motor rotor carry out Filtering Processing, harmonic component, DC component and interference signal are filtered, and the signal after the reduction is carried out carrying out after the processing and amplifying digital data transmission after mould/number conversion will be changed in control unit;
Input unit is set, is used for to control unit input setting signal, even the frequency setting value of the YZR motor rotor of the actuating of relay;
Relay unit is receiving opening of the closure of making war accordingly after the control signal or close point, rotor resistance is connected or cut away realizing;
Control unit, behind the frequency signal that receives the YZR motor rotor that frequency measurement circuit passes back, be translated into concrete frequency numerical value, its frequency setting value with the YZR motor rotor that makes the actuating of relay that the input unit input is set is compared, after the frequency of the YZR motor rotor that frequency measurement circuit is passed back reaches the said frequencies set point, send control signal to relay unit, make the actuating of relay in the relay unit.
2, a kind of frequency relay according to claim 1, it is characterized in that comprising in the described relay unit more than one relay, the corresponding setting input unit can be imported the more than one frequency setting value that makes the YZR motor rotor of the actuating of relay to control unit.
3, a kind of frequency relay according to claim 1; it is characterized in that described control unit is also by detecting the frequency of YZR motor rotor; to judge the running status of motor; when at corresponding gear; detection frequency and actual set value differ far and report to the police by the display unit prompting, and the control mains switch carries out power-off protection.
CN200910012713A 2009-07-24 2009-07-24 Frequency relay Pending CN101615873A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105915120A (en) * 2016-06-30 2016-08-31 苏州英威腾电力电子有限公司 Buffer control circuit and buffer control method of motor device
CN106200544A (en) * 2016-08-30 2016-12-07 大连国通电气有限公司 A kind of protection system and method preventing PLC from crashing
CN107565874A (en) * 2017-09-28 2018-01-09 包头钢铁(集团)有限责任公司 A kind of control device for full digital contactless hoisting equipment and control method
CN113141128A (en) * 2021-03-31 2021-07-20 首钢京唐钢铁联合有限责任公司 Wound motor rotor series resistance starting fault detection method, device and system

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105915120A (en) * 2016-06-30 2016-08-31 苏州英威腾电力电子有限公司 Buffer control circuit and buffer control method of motor device
CN106200544A (en) * 2016-08-30 2016-12-07 大连国通电气有限公司 A kind of protection system and method preventing PLC from crashing
CN106200544B (en) * 2016-08-30 2019-03-29 大连国通电气有限公司 A kind of protection system and method for preventing PLC controller from crashing
CN107565874A (en) * 2017-09-28 2018-01-09 包头钢铁(集团)有限责任公司 A kind of control device for full digital contactless hoisting equipment and control method
CN113141128A (en) * 2021-03-31 2021-07-20 首钢京唐钢铁联合有限责任公司 Wound motor rotor series resistance starting fault detection method, device and system
CN113141128B (en) * 2021-03-31 2022-07-15 首钢京唐钢铁联合有限责任公司 Wound motor rotor series resistance starting fault detection method, device and system

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