SU1526833A1 - Method of controlling power supply unit for electric precipitator - Google Patents

Abstract

The invention relates to the electrical purification of gases, in particular, to a method for controlling the power supply unit of an electrostatic precipitator, can be used in various sectors of the national economy and allows an increase in the degree of gas purification. A method of controlling a power unit consisting of controllable gates and a booster rectifier unit connected to an electric filter consists in phase control of controllable gates using alternating gradual reduction of the control control phase angle until the spark discharge is fixed in the electrode spacing of the electrostatic precipitator and jumped incrementing it by the specified value after that. In this case, in the case of arcing of arcing, the controlled valve does not turn on the supply voltage for several half periods. During the operation of an electrostatic precipitator, the phase angle increment is set so that it is greater than the value leading to arcing by a predetermined value, the monitored parameter characterizing the compliance of the set phase angle value with the dust-gas flow parameters is reduced, and when it reaches a predetermined critical value, phase angle by a given value, and as the specified controlled parameter, the ratio of the number of spark bits detected in each m of equal successive time intervals, to the number of spark bits in the first time interval, counted after switching on of the specified control valve. 1 hp f-ly, 1 ill.

Description

one

(21) 4310465 / 23-26

(22) 09/30/87

(46) 12/07/89. Bul 45

(71) Specialized enterprise for the repair and modernization of gas cleaning and ash removal systems

(72) S.N. Nemirov and I.B.Popov

(53) 68.052-12 (088.8)

(56) USSR Copyright Certificate No. 1225099, cl. In 03 C 3/68, 1980.

U.S. Patent No. 4,390,831, Cl. At 03 On 3/68, 1983.

(54) METHOD OF MANAGING AGTEGATPM ELECTRICAL POWER SUPPLY (ISRAET

(57) The invention relates to the electrical cleaning of gases, in particular, to a method for controlling an electrostatic precipitator power supply unit, can be used in various parts of the national health system and makes it possible to increase the degree of gas purification. The method of controlling a power unit consisting of controllable gates and a booster rectifier unit connected to an electrostatic precipitator consists in phase control of the controllable valves using alternating gradual reduction of the phase angle of the controllable valve until the spark discharge in the electrode gap is fixed and the electrostatic precipitator and incrementing it by a predetermined value after that. In this case, in the case of arcing, the controlled valve is not switched on for several half-periods of the supply voltage. During the operation of an electrostatic precipitator, the value of the phase phase angle is established so that it is greater than the value leading to the arc, by a specified amount, a controlled parameter characterizing the compliance of the set phase angle value with the parameters of the dust-gas flow is measured, and when it reaches it in advance set critical value reduces the phase angle value by a specified amount, and the ratio of the number of spark discharges detected in to channels on each of successive time intervals equal to the number of spark discharges in the first time interval starting after the incorporation of said controlled valve. 1 .p. f-ly, 1 ill.

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The invention relates to the field of electrical gas cleaning, in particular, to methods for controlling the power supply units of electrostatic precipitators, and can be used in the power industry.

chemical, metallurgical and other sectors of the national economy.

The aim of the invention is to improve the degree of gas purification.

The drawing shows a block diagram of a device for implementing a method for controlling an electrostatic precipitator power unit.

A device for carrying out the method comprises a power unit consisting of controllable valves 1 and a booster unit 2 connected to the electrostatic precipitator 3. The voltage sensor 4 on the electrostatic precipitator 3 is connected to the input of the spark discharge detector 5, the output of which is connected to the first computing unit 6 and unit 7 for forming the magnitude of change in the phase angle of switching on controlled gates (uif the input of the arcing detector 8 is connected to the step-up rectifying unit 2, and the output is connected to the input of the pause unit 9, output with the second input of the computational unit 6 and the first input of the unit 10 pulsed-phase control, and to the third input of the unit 7 forming the value A Lfg, the second input of which is connected to the output of the computational unit 6 and the output -phase control, output connected to controllable gates 1.

YcTpoi icTBo works as follows.

The voltage on the electrostatic precipitator 3 is increased by gradually decreasing from 180 the phase angle cfg of switching on controllable gates 1 produced by the unit 10 of the impul1 snc-phase: o th control. Each time a spark is detected in the electrostatic precipitator 3, the detector 5 generates a pulse by triggering a trigger that triggers the ds formation unit 7 on the first input. . The output signal of the unit 7 for generating the quantity ZI (5) is fed to the second input of the unit 10 of the pulse-phase control, which causes abrupt increases in the current value (jf by the initial angle of the cell equal to ft in block 7, In the electrostatic precipitator 3, a signal appears at the output of the arcing detector 8 that triggers the pause unit 9, the output of which is fed to the first input of the pulse control unit 10 of the open control, thereby stopping the reduction and blocking the start of control 1X b 1l she is 1 for several

half periods of supply voltage. In addition, the indicated signal of the arcing detector 8 is supplied to the third input of the B-7RUP1Y u formation unit 7 (ff,, causing an increase in / (f on the ve: 1 ichi 1y g /. But the end of the output signal from the 9-pause block is started on the second input computing unit 6, as well as with: interlocking the activation of controlled valves (-Rd again

five

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but decrease. After that, when there is no signal on:: the input terminal, the computing unit 6 counts the number of pulses arriving at its first input from the spark discharge detector 5 at equal time intervals T. The number of pulses in the first interval T is fixed-memorized by the computing unit 6, then calculating the ratio of the number of pulses in each of the subsequent intervals to the fixed-memorized value. When this ratio is reduced less than the critical one, the computing unit 6 generates an output signal arriving at the second input of the value generation unit 7, thereby causing a decrease. (, by the value of - in the case of P 1; .pl; 11 sigapal output of the detector. Signalization of the signal deducted 11: the logical block 6 is zeroed. Thus,) M searches for the minimum duality of the Beliche lffg at variable dust flow parameters. When the breakdown level is reached, the voltage on the electrostatic precipitator abruptly decreases by an amount determined by the phase angle Iq. Suppose that for the parameters of a dust-gas flow, the value of q is b

elk inadequate. This leads to the start of arcing. After turning off the controlled valve 1, the new value Jcpg is set for the pause time of the deionization of the interelectrode strip. If the specified new value is optimal for 1-meter gas and gas flow, then the penetration level is monitored with high accuracy. If the ibix parameter is changed in such a way that the value of ucfg becomes excessive, the frequency of the spark bits is reduced, and the computing unit 6 issues a command to decrease the number of Lfj.

Obviously, the effect of cleanness will be - the gas will be the Bimie, the less

value of. But the minimum reliable value is limited by the synchronization error of the 10-unit pulse-phase control with the supply network, and taking into account the distortion of the shape and frequency of the supply industrial network, it can not be set to less than 0.001 even when using precision synchronization. On the other hand, it was experimentally established that at d 0.05, the average corona discharge current, and hence the gas cleaning efficiency, is lowered. Thus, depending on the type of synchronization used, s are chosen as small as possible in the range of 0.03-0, OOH.

Claims (2)

1. A method for controlling an electrical power supply unit consisting of five 0 five 0 five five switching on controlled valves are in the range of 0.01-0.05 and 0 of controlled and enhanced-rectifying unit, which consists in measuring the voltage on the electrostatic precipitator electrodes and decreasing the phase angle of the controlled valves, fixing the spark discharge in the electrostatic precipitator, followed by a stepwise increase in the phase angle of the controlled valves and fixing the arc formation in an electrostatic precipitator, with a subsequent removal of the voltage applied to the electrostatic precipitator electrodes, for a predetermined number of half-cycle supply voltage, characterized in that, in order to nsheni walls of the gas cleaning hopping phase value yi-la produce it by this value every time the arcing is fixed in the electrostatic precipitator, the value of the control parameter is determined by calculating the ratio of the total number of detectable spark discharges in the electrostatic precipitator at equal successive time intervals to the number of fixed spark discharges in the first time interval after applying voltage electrodes of the electrostatic precipitator, compare the value of the control parameter with the specified critical value, and when the control parameter reaches the critical value, decrease The value of the phase angle of switching on the control 1 of the gates for the value of its selected jump change is applied. 2. The method of clause 1, which differs u and l so that equal time intervals for determining the value of the control parameter are chosen in the range of 2-10 s, and the value of the critical value of the control parameter is set equal to 0.7. Editor E. Papp Compiled by B. Dolotin Tehred M. Khodanich Proofreader N. Korol Order 7442/13 Circulation 498 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk-nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Subscription