英文原文The mine pit elevator measured precisely the fast microcomputer realizesThe mine pit elevator is the mine pit production important equipment, the load mineral, the material, the equipment and the personnel moves back and forth transportations duty in the well chamber, holds the extremely important position in the mine pit regular production. Moves reliably safely for the guarantee lift technique, the request control systems performance is good, must have the high velocity modulation performance and the position control.Along with the computer applied sciences swift development, uses the computer control system substitution original electrically controlled system is one tendency. As a result of the mine pit elevator control system highly complexity and to the security reliable strict request, domestic has not developed at present is more ideal, is suitable for the industry scene request the computer control system. This article introduced the author is engaged in a piece which this aspect works.1 To the microcomputer measured that the fast installment request To the microcomputer measured the fast installment the general request is: Resolution is strong, the precision is high, as far as possible short examination time. 1.1 resolution When carries on the rotational speed examination with the microcomputer, the resolution with changes was measured that the rotational speed which a survey meter digit corresponds the change quantity expressed. Supposes the rotational speed when become n2 by n1 causes the survey meter value to change a character, represents the resolution with Q:The resolution size and systems control precision relations are really big, the Q value is smaller, resolution is stronger, systems control precision is higher, it is measures the fast installment an important target.1.2 measured that fast precision Measured the fast precision is refers to measures the fast installment to the actual tachometric survey precise degree. If with n represents the observed value and the actual value difference, n represents the actual rotational speed, % represent the measuring error which expressed with the relative value, thenObviously, % is smaller, measured that the fast precision is higher; systems control precision will be also higher. The measuring error % sizes decided that in measured the fast parts manufacture precision, and with measured the fast method concerns.1.3 examination time The examination time is refers to between two time rotational speed sampling the time-gap. The examination times length the control performance influence is very big to the system, if the examination time is very long, then the system will realize the stable fast response with difficulty. The examination time is shorter, is more advantageous regarding systems control performances improvement.2 The microcomputer measured that fast general method By the electro-optical type revolving encoder and elevators axis solid joint, the elevator retransmits the certain amount every time (1080) the signal impulse, takes down the pulse number by the counter, and gives computer processing to realize the microcomputer to measure fast. Commonly used measured that the fast method mainly has the following two kinds.2.1 The M law measures fastThe M law measured that fast is reads the pulse integer which in the equal time-gap the revolving encoder sends out to figure out the rotational speed. The pulse number which sends out in the same time internal rotation encoder is different; the observed value is not same. The M law measured that fast schematic diagram as shown in Figure 1.By the counter the pulse counting which transmits to the revolving encoder, timer every other time T sends out an interrupt request to CPU, extracts corresponding according to the counting values size the rotational speed. The revolving encoder retransmits pulse 1080 every time, altogether has m pulse in the T time, then the rotational speed is:This kind measured that the fast method is by the counting value m size reflection rotational speed height, thus is called the M law to measure fast.(1) ResolutionMay result in according to the resolution definition by type (3):Obviously, the M law measured fast when the resolution has nothing to do with the speed size, concerns with rotational speed sampling period T.(2) measured that fast precision When measures using the revolving encoder fast, its measuring error decided that concerns in encoders manufacture precision and with the rotational speed size. Supposes between the revolving encoder two neighboring pulses the angular deviations are. p%, an examination cycles counting value is m, then the measuring error is:The rotational speed is lower, m is smaller, the measuring error is bigger, measured that the fast precision is lower. Along with the RPM drop measured that the fast precision reduces is the M law measures a fast shortco