JPH0459063A - System for controlling electrification of electrical dust collector - Google Patents

Abstract

PURPOSE:To always control electrification voltage to the optimum value by storing the electrification voltage V of an electrical dust collector and the frequency F of generation of sparks at the voltage, calculating electrification voltage maximizing electrifying effect from stored past values V, F and carrying out control. CONSTITUTION:When sparks are generated, electrification voltage V and the frequency F of sparks at the voltage are stored. Electrification voltage maximizing electrifying effect (V=V-aF) is calculated from stored values V, F and outputted. In order to renew the stored values V, F, electrification voltage is raised at prescribed time intervals by a fixed quantity. The latest values V, F stored within several to several ten min are used and irrational data such as data giving a smaller number of sparks at higher voltage are erased. Electrification voltage is stably controlled to the optimum value in accordance with the characteristics of a dust collector to be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a charge control method applied to a control device for a high-voltage charging device of an electrostatic precipitator.

[Prior Art] FIG. 3 shows a flow sheet of a conventional charge control method for an electrostatic precipitator. The control device increases the charging voltage at a predetermined speed up to the rated upper limit of the charging device while no spark is generated within the electrostatic precipitator. When a spark is detected in the dust collector, the control device lowers the charging voltage by a predetermined amount, and controls the charging voltage in accordance with the number of spark occurrences.

[Problem to be solved by the invention] As mentioned above, in the conventional control method, the charging voltage is always reduced when a spark occurs, but if you take into account the performance deterioration of the dust collector due to the reduction in the charging voltage, it will be slightly reduced. It is preferable to maintain the charging voltage at the number of sparks. On the other hand, in dust collectors where sparks are always generated when the voltage exceeds a certain level, the conventional method constantly increases the charging voltage until a spark is detected, resulting in performance deterioration due to frequent sparks. In such cases, operators had to occasionally lower the upper limit setting of the charging voltage.

The present invention aims to provide a method for calculating and controlling the above-mentioned charging voltage to always keep it at an optimum point.

[Means to solve the problem] The present invention takes advanced means to solve the above problems.

That is, the charging voltage V (or charging current) of the dust collector and the frequency F of the number of sparks generated at that voltage are stored in the control device, and the charging effect P (for example, V
-aF l-a is a constant) is calculated and a charging voltage that maximizes the P value is output to the dust collector.

[Function] In general, the charging effect of a dust collector is considered to be proportional to the value obtained by subtracting the uncharged state ratio at the time of spark generation from the voltage, for example, the above-mentioned V-aF. If a charging voltage that maximizes this value is output, this is the optimal charging state.

FIG. 2 shows two examples of characteristics of dust collectors.

(a) is an example in which the number of spark occurrences increases rapidly when the voltage exceeds a certain value v1, and in this case, the optimum voltage is clearly just below v1. The calculated value of P=V-aF is as shown in figure (e), and the charging voltage is at the 72 points where it is maximized, which is v
A value just below 1 matches the optimal point.

(b) is an example in which the number of sparks is not very related to the voltage, and P-V
-aF calculation, the charging voltage is the rated (maximum) value of the device v
It is held at 3 and does not drop every time a spark occurs.

[Embodiment] FIG. 1 shows a control flow diagram according to the method of the present invention. In this flow, when a spark occurs, the household appliance voltage V and the spark frequency F at that voltage are stored.

As described above, the charging voltage is determined by determining the point at which the charging effect PV-aF is maximum from the stored V and F values and output. V,F
In order to update the stored value, the charging voltage is increased by a certain amount at predetermined time intervals.

As the stored values of V and F, the latest values within several minutes to several tens of minutes are used, and unreasonable data (for example, data such that the higher the voltage, the fewer the number of sparks) is deleted.

Further, in this embodiment, a charging voltage is used as the value to be controlled, but a physical value correlated thereto, such as a charging current, may also be used.

[Effects of the Invention] With the above means, the charging voltage does not change each time a spark is detected, and is stably controlled to the optimum voltage according to the relationship between the charging voltage and the frequency of sparks at that voltage, that is, the characteristics of the dust collector to be controlled. be done.

[Brief explanation of the drawing]

FIG. 1 is a flowchart of a control method according to an embodiment of the present invention, FIG. 2 shows an example of characteristics of a dust collector, and FIG. 3 is a flowchart of a conventional control method. Applicant's representative Patent attorney Fuse 1) Katsumasa (a) (Spark frequency) ■ (Charging effect) ■2 ■ (C) Figure (b) ■3 ■ ■3 ■ (d)

Claims (1)

[Claims] Electricity characterized by storing the charging voltage V of the electrostatic precipitator and the frequency of spark occurrence F at that voltage, and calculating and controlling the charging voltage at which the charging effect is maximized from the stored past V and F values. Charge control method for dust collector.