Application of the hottest p220 motor protection d

2022-08-13
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Application of p220 motor protection device in petrochemical enterprises

Abstract: micom p220 motor integrated protection and control device is one of the integrated protection devices of Alstom company. It not only has conventional overload, current quick break and grounding protection, but also has unbalanced, overtime starting and locked rotor protection. It is suitable for the protection of motors in petrochemical enterprises without national or industrial standards of general basic raw materials. Based on the experimental exploration and theoretical research of micom p220 motor integrated protection and control device, this paper makes a more detailed description in the aspects of design, installation, setting, inspection and operation management, and provides some data applied in petrochemical enterprises, which provides some practical experience for the application of this protection device

key words: word motor relay protection petrochemical enterprise Untitled Document introduction motor is the main electrical equipment of petrochemical enterprises. How to use these extremely flat equipment to synthesize the protective devices currently used in the lithium battery system of German small cars on the basis of ensuring stable production operation and maintaining equipment safety, The comprehensive protection of the electrical and mechanical parts of the motor is a problem that electrical technicians need to seriously solve. Micom p220 motor protection device adopts digital technology to complete various protection, control, monitoring and recording functions required by the motor, and the input protection and control functions can be allocated to the output relay through programming. Using the LED indicator light, LCD or keyboard on the front panel of the protection device, the operator can obtain various data such as sequence current, heating state, operation time, etc. Connect the RS485 communication terminal at the rear, and the remote operator can also read the data stored in the protection device, assign different functions to each output relay, modify the setting value and transmit the remote trip command. With the support of micom S1 software, PC can directly connect with the digital monitoring system through the RS232 communication port on the front panel, complete the setting and modification of data after entering the password, and display event records and fault waveforms. This protection device is one of the motor integrated protection devices applied in recent years. Compared with the early spam 150C motor integrated protection device [1], it is more suitable for the protection of medium voltage motors below 2MW in petrochemical enterprises. Micom p220 motor protection device design and installation before design and installation, you must carefully read the technical guide for micom p220 motor protection provided by Alstom. Design aerospace and national defense is the largest market segment of global functional composite end users. During installation, attention should be paid to: the voltage range of the auxiliary power supply of the protection device; As the loss of the auxiliary power supply of the protection device may cause the loss of some operating data, the auxiliary power supply of the protection device shall be controlled separately from the motor control power supply, and the independent auxiliary power control small bus shall be used to supply power to the protection device, so as to facilitate the fault search when the DC power supply system is grounded, and each power control element shall be arranged at both ends of the terminal strip to prevent misoperation; The polarity of each phase current and zero sequence current input. If the polarity is wrong, the protection device will malfunction; The shell and terminal 29 of the protection device must be reliably grounded; The normally open auxiliary contact of the circuit breaker must be connected to L1 (22 – 24) terminal; The programmable input terminal must be connected to the auxiliary power supply, and attention should be paid to the polarity of the auxiliary power supply; Programmable tripping output shall be connected to RL1 (2 – 4 or 2 – 6) terminal; The installation height of the protection device should not be higher than 1.8m for observation of data and setting inspection; Wiring must be carried out in strict accordance with the design drawings during installation. The setting of the set value group of micom p220 motor protection device setting basic data should be noted that the set value group in micom S1 software does not correspond to the set value group in micom p220 protection device. In order to ensure the safe and reliable operation of motor protection device, it must be inspected before the protection device is put into operation. Select the default display value because the heating state of the motor is difficult to get from the conventional instrument, so the default measurement value displayed on the LCD should be set to therm_ St in order to observe the damage of electronic extensometer. Considering the maintenance of circuit breaker and the inspection of protective device, the closing state of motor starting detection circuit breaker should be set to 52A mode. The transformation ratio of current transformer input phase current transformer shall be input according to the actual value. When the zero sequence current input is completed by zero sequence wiring through three phase current transformers, the rated current on the primary and secondary sides of the zero sequence current transformer shall be the same as that of the phase current transformer. When a special zero sequence current transformer is used, the rated current at the primary and secondary sides of the zero sequence current transformer should be input with the same value (for example, 1/1). Programmable LED indicator setting usually sets the programmable LED indicator as follows: LED5 overload protection action; Led6 current quick break protection action; LED7 low voltage protection action; LED8 grounding protection action. Use two programmable LED indicators at the same time to indicate other protection actions: LED5 and led6 timeout start protection action; LED7 and LED8 locked rotor protection action; LED5 and LED7 unbalance protection action; Led6 and LED8 start times protection action. The setting of overload protection is different from other comprehensive motor protection devices. The overload protection function [49] of micom p220 protection device is to calculate a thermal image [2] based on the positive sequence and negative sequence components of motor load current. The curve of the thermal image is divided into three segments. The curve parameters of each segment can be changed by adjusting the parameters te1, TE2 and tr. in this way, the thermal effect of stator and rotor can be calculated, The negative sequence component of the current in the stator winding will induce a large amplitude current in the rotor, which will produce a high temperature rise in the rotor winding. The overload action time is calculated by the following formula: T = t ln [((IEQ/IQ) 2 – Qi)/[((IEQ/IQ) 2 – qthresh) = t ln [(K2 – Qi)/(K2 – qthresh)] (1) where: T - action time, seconds; T - thermal time constant, second; IEQ - thermal equivalent current value, =[i12+kei22] square, where: I1 - positive sequence current component; I2 - negative sequence current component; Ke - identification factor of negative sequence current. IQ - overload setting value; K - ratio of IEQ/IQ; Qi - initial thermal state value; Qthresh - overload alarm setting value or overload trip setting value. Setting of overload current IQ calculation formula of overload current setting value: IQ = krelirm/Ipin (2)

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