MCAC808 Full Digital AC Servo Driver

Summary

MCAC808 is a fully closed-loop digital AC servo driver designed and manufactured by our company with DSP. It consists of three feedback loops (position loop, speed loop and current loop). It can work in position, speed and torque mode. It is suitable for AC servo motors with driving voltage of 80V and power of less than 400W.

Characteristic

1) Position Control: Input Optically Isolated Pulse and Direction (PULSE/DIR) or Double Pulse (CW/CCW) Signals

2) Speed control: input is analog 0V-+3.3V voltage signal (input by P1)

3) Torque control: input is analog 0V-+3.3V voltage signal (input by P1)

4) Optical Isolation Servo Reset Input Interface ERC

5) Optical Isolation Fault Alarm Output Interface ALM

6) Optically isolated in-place output signal interface INPOS

7) Current Loop Bandwidth: (-3dB) 2KHz (Typical Value)

8) Speed Ring Bandwidth: 500Hz (Typical Value) Location Ring Bandwidth: 200Hz (Typical Value)

9) Input Interface of Orthogonal Encoder at Motor End: Differential Input (26LS32)

10) RS232C interface downloads parameters via PC or text display

11) Overcurrent and I2T; Overvoltage, Undervoltage, Overheat, Overspeed, Overdifferential Protection

12) Green light means operation, red light means protection or offline.

Technical index

1) Input DC Voltage Model Figure 30-80V (Typical Value)

2) 400W Continuous Output Power

3) Continuous output current 8A 20KHz PWM

4) Overload output current 20A (3 seconds).

5) protection

The peak value of overload output current is 40 A soil 10%.

Overvoltage Voltage Action Value 90V

Undervoltage Voltage Action Value 24V

6) Maximum Pulse Input Frequency 300K

7) Maximum RS232C speed 19.6Kbps (additional conversion interface required)

8) Use environment

Occasion: avoid dust, oil mist and corrosive gas as far as possible

Working temperature: 0~+50C

Storage temperature: -20C~+80CHumidity: 40-90% RH

Cooling mode: natural cooling or forced air cooling

9) Shape size 140x97x48

10) Weight about 500 grams

Servo system parameter adjustment and setting potentiometer (counterclockwise timing value decreases, clockwise timing value increases)

A: On the driver circuit board - a 7-bit DIP switch, where the position 1-3 is used to set the maximum current. For 2.5 times the rated current, the working mode is set at position 4-7.

4.1 Current Settings

5.3 Mode Settings

Speed and force distance are controlled, and analog input is made by P1. 0 is the largest negative, 3.3/2V is 0, 3.3V is the largest positive. B: The potentiometer has 11 scales which are turned counterclockwise to zero, clockwise to 10 and 5 in the middle.

P1: Position Feedforward Regulation P2: Position Proportional Gain Regulation P3: Position Differential Regulation P4: Speed Proportional Gain Regulation

The servo system consists of three feedback loops (position loop, speed loop and torque (current) loop). The reaction speed of the inner loop current loop is the fastest, and that of the middle loop must be higher than that of the outer loop position loop. Failure to comply with this principle will cause shock or poor reaction. The design of servo driver can ensure that the current loop has good response efficiency. Users only need to adjust the parameters of position loop and speed loop. The parameters of the system always restrict each other. If only the gain of the position loop increases, the output instructions of the position loop may become unstable, so that the response of the whole servo system may become unstable. Usually the following steps can be taken to adjust the system:

1) The position feed-forward and position differential are set as potentiometer scale (3), and the position gain and velocity gain are set at a lower scale (3), then the scale (0.5-1) lattice is reduced by increasing the velocity gain at least with vibration step by step without producing abnormal sound and vibration.

2) Increasing the position gain has at least vibration. Add position differential to no vibration.

3) Increase position feed-forward to minimize delay and overshoot.

4) If the motor has vibration during operation, the speed gain should be reduced appropriately.

5) If there is vibration when the motor stops, the position gain can be reduced or the position differential can be increased appropriately.

On the premise of no overshoot and no vibration in the whole response, the position gain should be set to the maximum. Then the velocity gain, position feed-forward and position differential are fine-tuned to find the best

value.

Port specification

Control signal input/output port X1 (D9 head)

Encoder feedback signal input port X2 (D15 header)

Power port X3

Control signal wiring

When the control signal is connected by a single terminal, the wiring diagram is as follows:

When the control signal is connected differently, the wiring diagram is as follows:

Note: When Vcc is 5V, R = 0

When Vcc is 12V, R = 1K, greater than 1/8W, 

when Vcc is 24V, R = 2K, greater than 1/8W resistance must be connected to the control signal terminal.

Wiring diagram

The typical wiring diagram of the servo system is as follows:

The driver can provide a +5V, maximum power supply of 80mA to the encoder. By using the four-fold frequency counting method, the resolution of the encoder multiplied by four is the number of pulses per turn of the servo motor.

Installation dimension