MCAC808 all-digital AC servo drive system adopts high-performance digital signal processor (DSP) and integrated circuit, and come out to be a cost effective product with simple circuit, high integration, easy operation, and strong practicability. MCAC808 provide three feedback loops: position loop, velocity loop and current loop. Three work control mode: position, velocity and torque. MCAC808 matches with AC servo motor under 80V and 400W.

Features

Position control: light isolate input PULSE/DIRECTION or CW/CCW signal;

Speed control: input simulate 0-3.3V voltage signal (speed input by P1);

Torque control: input simulate 0-3.3V voltage signal (torque input by P1);

Light isolation servo reset input interface ERC;

Light isolation servo failure alarm output interface ALM;

Width of current loop (-3dB) 2KHz (standard);

Width of velocity loop: 500 Hz (standard);

Width of position loop: 200 Hz (standard);

Quadrature encoder input interface at motor side: differential input (26LS32);

Allow parameters download by pc or text displayer through interface RS232C;

Perfect protection against overload, I2T, over-voltage, over current, overheating, short circuit, circuit interruption, chip damage;

Green light for on, red light for protected mode or offline.

Specification

Input DC voltage range 30—80v(standard);

Continuous Output power:400W;

Continuous output current: 8A ,20KHz PWM;

Overload output current: 24A(3s);

Protection:

Over current initiated peak value: 50A±10%;

Overload I2T current initiated value: 300% 5s;

Overheating initiated value: 80℃;

Over voltage initiated value: 90V;

Under Voltage initiated value: 24V;

Maximum pulse input frequency:300K;

Maximum RS232C speed: 19.6Kbps (an extra transfer interface required);

Working environment:

No dust, no oil mist and no corrosive air;

Working temperature: 0-50℃;

Storage temperature: -20--+80℃;

Humidity:40-90RH;

Cooling method: natural air cooling and forced air cooling;

Dimension: 140 x 97 x 48 mm

Weight: about 500g

Parameter adjusting and setting

(potentiometer adjusting, CCW to minimize value, CW to maximize value)

A) Four pins on the Circuit Board for control mode setting, 1, 2, 3, 4 respectively from the outer side.

1.      no plug in, position mode is pulse/direction;

2.      plug in 1, speed control, speed input by P1;

3.      plug in 2, torque control, torque input by P1;

4.      plug in 1 and 2, position control for positive pulse/negative pulse input;

5.      plug in 3, position control pulse/direction, but converse running direction.

B) 11 scale on the potentiometer, CCW to minimize the value to 0, CW to maximize the value to 10, and 5 in the middle.

P1 : Position Feed-forward Control

P2: position proportional gain control

P3: position differential control

P4 : velocity proportional gain control

Servo system includes three feedback loop: position, velocity and torque(current). The inner loop responses with the fastest speed, and the middle loop must responses faster than the outer loop. A vibration will happen when the rule has not been followed. Customer need adjust the parameter of position loop and velocity loop only. Parameters of system would restrict each other, the output of position feedback would be unstable when just only the position feedback gains, which would lead to an unstable result of the whole servo system. Customer might take the following adjustment procedure as a reference:

1.      set P1 and P3 to (3) on the potentiometer, set the P2 and P4 to (3), and then increase the P4 slowly till a vibration happens, then return 0.5 to 1 scale.

2.      increase the P2 till a vibration happens, and then increase the P3 till the vibration disappears.

3.      increase the P1 to fulfill a minimum lag and overshoot.

4.      decrease the P4 properly when a vibration happens during the motor operation.

5.      decrease the P2 or increase the P3 properly when a vibration happens when the motor stop.

6.      decrease the current properly when a magnet noise happens.

Maximize the P2 under the condition of none overshoot and no vibration. And then minitrim the P4, P1 and P3 till a perfect setting.

Ports detail

X1: control signal input / output (D9 male)

X2: feedback signal input of encoder(D15 female)

X3: power