Inverter parameters set in the debugging process is very important. As the parameters set properly and can not meet the needs of production, leading to start, brake failure, or work often tripping, and in severe burning power module IGBT device or rectifier bridges. Inverter on the variety of parameters have different volume. General single-function control of inverter is about 50 to 60 parameters, multi-function control of the converter has more than 200 parameters. However, more or less regardless of parameters, whether in the debugging parameters must all re-align it? No, most of the changes from time, as long as you can by default setting, as long as the use value of the original factory settings can be re inappropriate, such as an external terminal operations, analog operation, base frequency, maximum frequency, maximum frequency, lower frequency, start time, braking time (and mode), hot electron protection, overcurrent protection, the carrier frequency, stall protection and overvoltage protection must be adjusted so that positive. When the operation does not fit, then adjust the other parameters.
Some common problems on site commissioning treatment
Starting time setting principle is not appropriate short length, the specific values see below. Over-current setting value is too small OC, and increase can be increased to maximum 150%. Experience the value of 1.5 ~ 2s/kW, low-power take bigger; greater than 30kW, taking> 2s/kW. Press the Start button * RUN, motor locked rotor. Shows the load torque is too large, starting torque is too small (to improve). Then press STOP to stop immediately, otherwise, over time, the motor should be burned. Is blocked due to motor does not change state, anti-electric E = 0, then, impedance value Z = 0, only the DC resistance is small, then the current lot is very dangerous, we should trip OC action.
Braking time setting principle is the appropriate length should not be short, easy to produce over-voltage trip OE. Table 1, the specific value of deceleration time. Free brake fans on the pumps suitable, easy to implement quickly a strong brake severe "water hammer" effect.
Starting frequency setting conducive to accelerating the start, especially more suitable for light loads, heavy load starting frequency value on big, resulting in increased starting current, easier to skip the current in the low frequency band OC, usually starting from 0 the right frequency.
Starting torque setting conducive to accelerating the start, especially in light load is more suitable for heavy load starting torque value is large, resulting in increased starting current, easier to skip the current in the low frequency band OC, usually starting torque starting from 0 appropriate.
Base frequency setting
Base frequency of 50Hz, the standard is 380V, the V / F = 380/50 = 7.6. But the heavy load (such as extrusion machine, washing machine, drying machine, mixing machine, mixer, dryer, etc.) often can not start, but adjust the other parameters are of no avail, then the base frequency adjustment is effective. 50Hz setting will decrease, can be reduced to 30Hz or below. At this time, V / F> 7.6, which is particularly low in the same frequency band increased when the output voltage (ie, torque U2). It can be a good general starting heavy loads.
Braking voltage handling
Braking voltage is due to the short braking time, braking resistor value is too small which caused growth through appropriate time to increase the resistance can be avoided.
Braking the choice of methods
(1) braking. Use of general braking, the energy consumption of the resistor to the form of heat loss. At lower frequency, braking torque is too small, to produce crawling behavior.
(2) DC braking. Parking or stopping place for accurate, non-crawling phenomenon, combined with dynamic braking, when the general 20Hz DC braking,> 20Hz when braking with energy.
(3) regenerative braking. For 100kW, speed than D 10, alternately or Reversible alternating high and low speed, cycle time is short, this case, the application of regenerative braking, energy back up to 20% of the motor power. More specific details of the analysis and parameter selection.
No load (or light load) jump OC
Actually, the no-load (or light loads), the current is small and should not jump OC, but the actual occurrence of such a phenomenon, often because of compensation voltage is too high starting torque is too large, so that excitation saturation is so severe excitation current is serious, resulting in large peak-current trip OC, the appropriate value to decrease or restore the factory or put 0.
Starting time jump in the low-frequency 20Hz OC
Is due to excessive compensation, high starting torque, starting time is short, protect the value is too small (including over-current value and over-current stall value), can reduce the base frequency.
Difficult start, not start
General equipment, GD2 moment of inertia is too large, resistance torque is too large, but also heavy start, large fans and pumps often similar situation, the solution: reduce the base frequency; appropriately increasing the starting frequency; appropriate increase starting torque; reduce the value of the carrier frequency 2.5 ~ 4kHz, increase the value of the effective torque; reduce start-up time; promoting the conservation of value; set the load from the start with no load or light load into that of the fan small inlet valve may be relevant.
After the motor using the inverter temperature increase, increased vibration, increased noise
Our carrier frequency setting is 2.5kHz, are lower than the usual purpose of focus from the use of security, but more generally reflects the existence of these three problems, by increasing the carrier frequency value, the problem is solved. Transmission and press start button did not respond after RUN
(1) The panel did not set the frequency;
(2) motor fixed, this situation must immediately press "stop STOP" and check the following articles: reaffirmed the correctness of circuits; reaffirmed the code set (especially the part related with the start); whether the operation mode setting on; measuring input voltage, R, S, T three-phase voltage; PN DC voltage measurement; measuring voltage switching power supply in each group; Check drive circuit plug contacts; inspection panel circuit plug exposure; be re-energized after a comprehensive examination.
