SU442584A1 - Charging method of charging device - Google Patents

Description

one

This invention relates to methods for charging and measuring aerosol parameters.

In order to achieve the required accuracy of measurements when charging particles, two conditions must be fulfilled: identical particles must acquire equal charges in the charging device; the particles should not settle in the charge device.

The known method for feeding a three-section charging device is explained in the circuit shown in FIG. one.

The circuit contains electrodes 1-4, a high-voltage source of constant voltage 5, a high-voltage source of alternating voltage 6. The system of electrodes 1, 2 forms the first section of the corona discharge (CKR-1), the system of electrodes 2, 3 - the charging section of the ES and the system of electrodes 3, 4 - the second section of the corona discharge (SCR-2). When a constant high voltage is applied from the high-voltage source 5 to the electrodes 1-4 in the CRP-1 and CKR-2, a corona discharge occurs. In both sections, the like ions move from the corona electrodes 1 and 4 to the grid electrodes 2 and 3. On The electrodes 2, 3 are supplied with an alternating high voltage from source 6. As a result, the electric field in the ES for one half-period favors the penetration of ions from CKR-1, and during the second half-period -

from TFR-2. The particles are charged as they move through the CS. In a charging device of this type, a constant intensity and concentration of ions over the entire CS cross section is achieved. Therefore, regardless of the trajectory, the same particles in the CS acquire equal charges. Since the field in the ES is alternating, the particles, when moving through the ES, oscillate one-way through the line of translational motion, but do not drift to the walls under the action of an electric force and therefore do not settle.

The disadvantages of the known method of nutrition

are excessive current consumption due to the large amount of voltage in the TFR during non-working periods and a large amount of the required source voltage 5. To eliminate the noted deficiencies,

According to the proposed method, alternating voltage is applied to the corona-carrying electrodes 1 and 4 of the charging device along with a constant voltage, which changes synchronously with the voltage in the charging section in such a way that the working voltage between the electrodes of the TFR reaches the required half-period Up, and during the non-working half-period, is reduced to a level at which the crown is impossible (for example, to

zero). The essence of the proposed method is explained in FIG. 2, which shows the enuras of stresses. Here Uio, Uw, Uzu, Ui, u, t / i2, / 43 are the potentials of the electrodes relative to the base with zero potential; io (Uw) is a constant voltage applied to corona electrodes 1 and 4; io () is the amplitude of the alternating voltage applied to the corona electrodes. In the working half-period, the voltage amplitude between the corona electrode 1 and the grid electrode 2 is:. + lf ao | -l o |, In the non-working half-period: / 12 | ь, „| - | o;„ | - у, о |. Let, for example, -4 kV, the voltage amplitude in the ES be L2o 5 kV. Suppose that with the selected design of the charging device, the corona in the TFR is absent if the voltage between electrodes 1 and 2 is less than 2 kv in modulus. Then the limiting modes of nutrition, in which the crown is absent in the TFR during the non-working half-period, are the following: 1. UIQ - 1 KB, apt. working half-period f / i2 -4 sq. non-working half-period sq. 2. KB, sq. working half-period -4 square non-working half-period t / i2 -2 square. The mode in which the voltage f / ia is zero during the non-working half period is set at KB and q. With the above method of feeding the charging device electrodes, the breakdown in the TFR during the non-operating half-period is completely eliminated, the current in the TFR in the non-operating half-period ceases, the voltage of the power supply sources is minimal. Finally, the electric wind is completely eliminated in the TFR during the non-working half period, and this stabilizes the flow of air in the charging device. The proposed method of feeding the charging device is implemented by the circuit shown in FIG. The circuit contains electrodes 1–4, voltage generators 5 and 5 of BbicoKoro, synchronization unit 6. A constant voltage is removed from the output of each generator (/ o from generator 5 and / 40 from generator 5) and the bipolar voltage (/ o from generator 5 and / 40 from generator 5) —Sync block 6 provides a time shift between voltages / W and / 4 ° for half a period. In order to ensure the operating mode of the charging device, in which 5 kV, / 12 (/ 4z) is equal to -4kV in the working period, and zero to non-working one, each of the generators 5 and 5 must produce a constant voltage kV and a variable voltage amplitude and 10 and 40 7 square meters. AC voltage through a divider RiRziRsRi) with a transfer ratio of 5/7 goes to the AP electrodes and provides the desired operation mode of the ES, and through the capacitance Ci (C2) this voltage goes to the corona electrodes of the RMS, where it is summed with a constant voltage / io ( / 4o), which achieves the optimum mode of operation of the SCR and the entire charging device. Since the current in the ES does not exceed 10% of the current in the TFR, the divider RiRziRsR-i) is chosen sufficiently high-resistance and practically does not increase the current consumption from the high-voltage source. The subject of the invention is a method of feeding a charging device comprising two corona electrodes between which there are two electrodes — grids of a charging section fed by alternating bipolar voltage, characterized in that, in order to reduce the magnitude of the voltages used in the device and the magnitude of the consumed AC power is applied to the corona electrodes in synchronism with the alternating bipolar voltage. An alternating bipolar voltage with a constant component is applied.

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