Stepper motor in the use of two phase stepping motor, it found that the stepper motor torque is small, or short of additional torque of nominal value, so we have to increase the scale of the stepper motor and the nominal current, in order to meet the power demand. Sometimes it is not actually motor problem, but in choosing or stepper motor drives, improper setting of operating current, there are, no show the maximum power of the stepper motor. First of all, from the drive into consideration, now most of the two phase stepper motor driver is to choose the output of the whole bridge connection of four lines, if two phase stepper motor is also four wire, according to the setting of the nominal current of motor drive should be correct, and the highest power, maximum output torque can reach. Now, most new produce of stepper motor is this way. Now Internet users are mostly bought secondhand early yield of stepper motor, more is two phase six wire (Four groups of two to coil in series, each with the center tap)And a small amount of eight wire (Four groups of two independent coil)。 Is two phase six wire stepper motor has two kinds of connection, the first is to give up two center tap, the actual is to each group together using two phase coil, motor torque and high power, but the function is poor. The second is to center tap and end, the high speed connection motor function better, but each phase has a set of leisure, coil wall small torque and power is lower. Now Internet users are mostly wiring way to choose the first one. This presents a problem, two phase drive current how old should be set right, are generally according to the motor nominal current value to set, it is presented in front of the said power to the motor. General stepping motor phase current is the current (Or resistance), is the current value of the coil in each group (Or resistance), if two phase six wire stepper motor to choose the first connection, equivalent to two sets of coil together, then the resistance increase, each phase current reduce extra homework, even if the drive is set to the nominal current also can not meet the additional output value of every phase. So when choosing drive and stepper motor current matching problem. The correct way is to drive output current Settings should be for stepper motor extra zero phase current. 7 times (Is not generally thought together current binary)。 For example, for example, a two phase stepper motor with a center tap, nominal current is 3 a, drive current should be set to 3 * 0. 7 = 2. 1A。 So I present you although chose 3 a stepper motor, it actually power is equivalent to 2 of two phase four wire system. 1 a stepper motor. Talk about eight stepping motor of wire connection, there are two kinds, the first is to apply every two coil series, so the drive current is also set to 0 of the motor phase current. 7 times, this kind of connection motor calorific value is small, but high speed function. The second kind of connection is applied every two coil in parallel, the current drive is set to 1 of motor phase current. Four times, its advantage is high speed function better, but the motor calorific value is big, but stepping motor is a little temperature is normal, just below the degaussing temperature of the motor, general stepping motor demagnetization temperature around 105 degrees. So you have a stepper motor output current can not be adjusted of the drive (Refers to two phase full bridge output drive, such as net friend common TA8435, TB6560 and A3977 driver chip)After, how to choose stepper motors is very important, if your drive is 2 a, try choosing two phase four wire electric motor (2 aSuch as second-hand Japanese Oriental motor are mostly the)If you choose, the six wire motor will have to choose a nominal phase current is 2/0. 7 = 2. 9 (About)The motor. In order to better play to the role of the drive. But if you choose the drive is half bridge output (Such as SLA7062M, SLA7026 driver chip), it can only meet, the six wire motor drive current and motor nominal current is common. But this drive is now rarely and low power. Lines to for six or eight stepping motor phase coil in parallel operation, can play a maximum output torque and showed very good dynamic function, six line motor is unable to connect in parallel, the actual is now in the internal together, the public end of the series is the center tap. As long as eight lines of the motor coil can be used in parallel. If can turn the motor back cover, take a look at the inside of the connection structure, is the ability to change, make six line motor into eight line, so that it can be used in parallel, but not all six lines of motor can be changed, as long as seen from behind the motor may change the way of connection joint, and some motor is solder joint, the restructuring requires sophisticated technology. I has now gone for stepper motor, the series can also be used in parallel, the parallel use of phase current is 1. 4 times, greatly improve the working function, high-speed torque is increased, too.
