Sices HS 315, Техническое руководство

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Technical Handbook 137
3) Measure the period of oscillation (the time between two consecutive voltage peaks).
4) Set "P" to a slightly lower value than the one obtained by dividing the current value by 2.2.
5) Set the "I" to the calculated value by dividing 1.2 for the oscillation period measured before
(in seconds). It can be set a lower value degrading the performance but increasing stability
margin.
6) Some other fine tuning might be necessary. Verify how the system work with low, medium
and high load. In case there is still an instability of the system, reduce further the value of
"P".
To overcome the difficulties of measuring the period of oscillation, it is possible to go on,
referring to what said in the previous paragraph, from step 6 included, excluding points 3 and
5. Instead of step 5, increase/decrease "I" (after arranging "P" at step 4) to achieve the optimal
performance.
P factor is not able by itself to perform a good regulation. To reduce the error, P should be
increased, but after a threshold, the system becomes instable. Usually the P value set using
the explained method is the better compromise between performance and stability.
To get a good adjustment, it is necessary to set "I" factor. Even small values of the parameter
"I" increase the performance of the system. Value, obtained used the explained method,
usually give the better performance. However, it is not critical and can be set in a wide range
of values.
Remember that the factor "I" accumulates adjustment errors: delays in the recovery of the
error can cause over-elongations (over-shoots) or under-elongations (under-shoots).
Moreover, too high value of “I” lead to system instability.
Once the value that gives a good performance is found, try to decrease it until the performance
drops below the expected minimum. Then select the actual value in that range as compromise
In some cases, could be necessary to start the procedure with a minimum “I” value to allow
the controller a minimum regulation capability compatible with the system. A very small value
of "I" (0.01) can be used with minimal effect on the procedure.
To improve the efficiency of the generator, it should be used as little as possible; when used,
it should work at a sufficiently high power (the generators have the best efficiency around 80%
of rated power).
In practice, therefore, the generator should try to charge the batteries with the maximum
possible current, thus reducing the charging time (using only the BULK phase - see below). In
this way, however, the batteries do not charge 100% and it is therefore necessary, from time
to time, to carry out a complete charge cycle (full or equalization charge).
HS315 can perform both "standard" and "full" charge cycles. To allow the operator to
differentiate between the two charge cycles, HS315 provides two sets of parameters:
Cycle Standard Full
Menu 2.5.3 2.5.2
Charge current in BULK mode. P.9682 P.9675
End charge voltage for BULK mode. P.9683 P.9676
End charge current for ABSORBTION mode. P.9684 P.9677
Maximum charge duration in ABSORBTION mode. P.9685 P.9678
Charge voltage in FLOAT mode. P.9686 P.9679