YASKAWA ∑ - II Series SGMBH/SGDH AC Servo System

Yaskawa ∑ - II Series SGMBH/SGDH Servo Drive System: Technical Explanation and Application Guide

System Overview and Core Components

The ∑ - II series servo drive system mainly consists of two parts: SGMBH servo motor and SGDH servo driver (SERVOPACK), forming a high-performance closed-loop control system. This system is designed specifically for high-power applications ranging from 22kW to 55kW at a voltage level of 400V, meeting the stringent requirements for high dynamic response and stability in industrial sites.

1. SGMBH servo motor

SGMBH motor is a synchronous (permanent magnet) servo motor in the ∑ - II series, which has the following significant characteristics:

High torque output: The rated speed is 1500 min ⁻¹, the maximum speed can reach 2000 min ⁻¹, and it provides up to 200% instantaneous peak torque, ensuring that the equipment has strong power during start-up and acceleration.

Multiple capacity options: Offering 10 specifications ranging from 22kW to 55kW (such as 22kW, 30kW, 37kW, 45kW, 55kW) to meet different load requirements.

High precision feedback: Equipped with a 17 bit incremental encoder as standard, and can choose between 17 bit or 20 bit absolute encoders to achieve high-precision position and velocity detection.

Durable and sturdy: Adopting a fully enclosed, self cooling (with fan) structure, with a protection level of IP44, suitable for harsh industrial environments such as dust and oil mist. The motor is equipped with a built-in thermal protector (Thermostat) to monitor the temperature of the motor and prevent overheating damage.

2. SGDH servo drive

The SGDH driver is a servo amplifier specifically designed for SGMBH motors. Its core function is to convert instructions (analog or pulse) from the upper controller into three-phase AC power to drive the motor and achieve high-precision closed-loop control.

Multi functional control: supports three basic modes: speed control (analog reference), position control (pulse train reference), and torque control (analog reference), and can flexibly switch multiple composite control modes through parameters.

Integrated operation and monitoring: Built in panel operator, can also be connected to handheld digital operator (JUSP-OP02A-2) for parameter setting, status monitoring, trial operation, and fault diagnosis.

Rich I/O interfaces: Provide all input and output signals required for interaction with the upper computer through the CN1 (50 pin) connector, including servo ON, alarm, pulse input, analog reference, encoder frequency division output, etc. The CN2 connector is used to connect the motor encoder.

System integration and installation wiring

Correct installation and wiring are the foundation for stable operation of servo systems. The ∑ - II series products have fully considered the installation convenience and anti-interference ability of industrial sites in their design.

1. Installation of servo motor

Installation environment: The motor should be installed indoors, without corrosive/flammable gases, with good ventilation, an ambient temperature of 0-40 ° C, and a relative humidity of 20% -80% (without condensation). For environments with oil mist or moisture, it is necessary to install protective covers and use motors with oil seals.

Mechanical connection: The motor shaft and load shaft need to be precisely aligned through a flexible coupling. Before installation, the anti rust paint on the shaft end should be removed to avoid direct impact on the shaft end and prevent damage to the internal encoder. The allowable radial and axial loads of the motor must strictly follow the manual regulations.

Electrical connection: Connect the motor power lines (U, V, W) to the corresponding terminals of the driver. The built-in fans (U (A), V (B), W (C)) of the motor need to be connected to a three-phase 380-480VAC power supply and ensure that the fan rotates correctly (the wind direction blows from the non load end of the motor to the load end). The built-in thermal protector (1, 1b) must be connected to the control circuit to cut off the power supply when the motor overheats.

2. Installation of servo drive

Installation method: The SGDH driver adopts a base installation method and must be vertically installed inside the control cabinet to ensure heat dissipation.

Heat dissipation requirements: The drive mainly relies on natural convection or forced air cooling for heat dissipation. When installing multiple drives side by side, a gap of at least 10mm should be left between the left and right sides, and a gap of at least 50mm should be left between the top and bottom. It is recommended to install a cooling fan at the top to ensure that the ambient temperature does not exceed 55 ° C.

Main circuit wiring: The input terminals (L1/R, L2/S, L3/T) of the driver main circuit are connected to a three-phase 380-480VAC power supply. The control circuit power supply (DC24P, DC24N) needs to be connected to 24VDC. The motor output terminals (U, V, W) are directly connected to the servo motor. The regeneration resistor terminals (B1, B2) can be connected to external regeneration resistor units as needed.

Grounding and anti-interference: The grounding terminal (⨁) of the driver and the grounding terminal (FG) of the motor must be reliably grounded with a grounding resistance of less than 100 Ω. The signal line and power line must be wired separately with a minimum interval of 30cm. It is recommended to install a noise filter on the input power side and surge suppressors on the relay and contactor coils to suppress electromagnetic interference.

Core functions and parameter configuration

The strength of SGDH drivers lies in their highly configurable internal control algorithms and rich I/O capabilities, which can adapt to diverse application scenarios by setting parameters.

1. Control mode selection

The control mode can be flexibly selected through parameter Pn000.1, mainly including:

Speed control (0): Receive ± 6V to ± 10V analog voltage from the upper computer as a speed reference. The internal speed loop of the drive is completed.

Position control (1): Receive pulse trains (direction+pulse, CW/CCW or 90 ° phase difference two-phase pulse) from the upper computer as position commands. The driver completes position and speed loops internally. The electronic gear function (Pn202, Pn203) can convert input pulses into any mechanical movement distance.

Torque control (2): Receive ± 1V to ± 10V analog voltage from the upper computer as a torque reference. In this mode, the motor output torque is proportional to the input voltage.

Composite mode (3-9, A, B): For example, switching between speed/position/torque modes through external contact signals, or using contact inputs to select preset internal speeds for control.

2. Input/output signal configuration

The input signals (such as servo ON/S-ON, forward/reverse overtravel prohibition P-OT/N-OT, alarm reset/ALM-RST, torque limit/P-CL//N-CL) and output signals (such as servo alarm ALM, positioning completion/COIN, speed consistency/V-CMP, rotation detection/TGON, servo preparation/S-RDY) of the driver CN1 connector can be redistributed and polarity set through parameters (Pn50A-Pn50D, Pn50E-Pn512), greatly improving compatibility with different upper computer systems.

3. Key Function Settings

Electronic gear: By setting Pn202 (numerator) and Pn203 (denominator), the input pulse number can be flexibly converted into the actual rotation angle of the motor, simplifying the calculation of mechanical transmission ratio.

Torque limitation: Internal torque limitation can be set through parameters Pn402/Pn403, or dynamic torque limitation can be achieved through external contacts (/P-CL//N-CL) and analog voltage input (T-REF) to effectively protect mechanical loads.

Overtravel protection (OT): When the P-OT or N-OT signal is triggered, the stop mode can be set through parameter Pn001.1 (such as dynamic braking stop, servo lock after deceleration stop, free sliding stop), and the emergency stop torque can be set through Pn406.

Absolute encoder function: When using a motor with an absolute value encoder, it is necessary to enable it through parameter Pn002.2 and connect the battery (BAT+, BAT -). The auxiliary function Fn008 allows for absolute encoder reset and setting, while Fn013 allows for modification of multi turn limit values.

Debugging and trial operation

To ensure the safe and reliable operation of the system, strict trial operation procedures must be followed.

1. Preparation before trial operation

Safety check: Confirm that all wiring is correct and error free, especially the power line, motor line, and encoder line.

Empty load trial operation (first step): key step. It is necessary to disconnect the motor from the mechanical load (disconnect the coupling) and only allow the motor to run idle. The purpose of this stage is to verify the basic functions of the motor, driver, and encoder.

Use a digital operator to drive the motor in JOG mode (Fn002) and check the rotation direction and smoothness.

Check the status of the input signal (through monitoring mode Un005) and confirm that signals such as servo ON and overtravel are valid.

Check if the motor operates normally without load, and if there are any abnormal noises or vibrations.

2. Load trial operation and automatic tuning (Step 2)

Connect the load: After confirming that the no-load operation is normal, connect the motor to the mechanical load.

Auto tuning (Fn001): The SGDH driver has built-in online auto tuning function. By setting Pn110.0 to "1" (continuous tuning), the driver will automatically recognize the load inertia during actual operation and adjust the speed loop gain (Pn100), integration time constant (Pn101), position loop gain (Pn102), and torque reference filter time constant (Pn401) accordingly to achieve optimal system response. Users only need to select the mechanical rigidity level (1-10 levels, the higher the value, the higher the rigidity) through Fn001, and the automatic tuning will automatically optimize the gain. For systems with minimal load changes, tuning can be set to only occur during the first run.

Save tuning result (Fn007): Save the load inertia ratio (Pn103) calculated by automatic tuning to EEPROM for direct use during the next power on, without the need for re tuning.

Advanced Adjustment and Optimization

For applications that pursue ultimate performance, the system response can be optimized by manually adjusting the servo gain.

Basic gain adjustment principle: The servo system consists of a current loop, a velocity loop, and a position loop in order from the inside out. The response speed of the inner loop must be higher than that of the outer loop. Therefore, to increase the position loop gain (Pn102), it is necessary to first increase the velocity loop gain (Pn100). If the position loop gain is set too high and the velocity loop cannot keep up, it will cause velocity reference oscillation and prolong the positioning time.

Manual gain adjustment steps:

Firstly, set the load inertia ratio (Pn103) correctly. This is a prerequisite for accurately setting the speed loop gain.

Gradually increase the speed loop gain (Pn100) until the mechanical system begins to produce slight vibrations or noise, and then slightly decrease. Set the integration time constant of the speed loop (Pn101), and the empirical formula is Pn101 ≈ 4/(2 π× Pn100).

Gradually increase the position loop gain (Pn102) and observe the positioning time until the positioning response is satisfactory and there is no overshoot or oscillation.

If there is mechanical resonance, the torque reference filter time constant (Pn401) can be adjusted or notch filters (Pn408, Pn409) can be enabled to eliminate vibrations at specific frequencies.

Auxiliary optimization function:

Feedforward control: By setting position loop feedforward (Pn109) or velocity feedforward (Pn207.1), tracking error can be reduced and positioning time can be shortened. However, excessively high feedforward values may lead to overshoot.

Mode Switch: By setting Pn10B, the speed loop can be switched from PI control to P control during acceleration or deceleration when torque, speed, or acceleration exceeds a threshold, in order to suppress overshoot and oscillation and shorten the setting time.

Speed bias: Set through Pn107 and Pn108, when the error pulse accumulates to a certain degree during position control, an automatic speed bias is added to quickly eliminate errors and shorten positioning time.

Operation and monitoring

SGDH drivers provide multiple ways to operate and monitor, facilitating on-site debugging and maintenance.

Digital Operator:

Built in panel operator: located on the front panel of the driver, it can perform basic operations such as status display, parameter setting, monitoring, alarm reset, etc. through buttons and 7-segment LED digital tubes.

Handheld digital operator (JUSP-OP02A-2): Connected through the CN3 interface, it provides richer functions and a more user-friendly interface. In addition to basic functions, it can also perform JOG operation, zero point search, alarm tracking, parameter initialization, and other operations.

Main modes: status display mode (Un000, etc.), parameter setting mode (Pn000, etc.), monitoring mode (displaying speed, torque, input/output signal status), auxiliary function mode (Fn000, etc., used for JOG, automatic tuning, alarm tracking, absolute encoder settings, etc.).

Monitoring function:

Real time monitoring: The monitoring mode (Un000-Un00D) can display key parameters such as the actual motor speed, input speed reference, internal torque reference, input/output signal status, and error pulse number in real time.

Alarm Traceback: The driver can record the last 10 alarms (Fn000) that have occurred, facilitating troubleshooting.

Analog Monitor: Through the CN5 interface, two analog signals (such as speed, torque, and position error) can be output for connecting oscilloscopes and other instruments for waveform analysis, facilitating advanced debugging.

Maintenance and fault diagnosis

Regular maintenance and effective fault diagnosis are key to ensuring the long-term stable operation of the system.

Regular maintenance and inspection:

Servo motor: Daily inspection for vibration, noise, and appearance. Regularly (at least once a year) check the insulation resistance (should be greater than 10M Ω). For motors with oil seals, it is recommended to replace the oil seal every 5000 hours of operation.

Servo drive: Regularly (at least once a year) check for dust and loose screws inside. According to the operating environment, replace vulnerable parts at predetermined intervals (such as 4-5 years for cooling fans and 7-8 years for electrolytic capacitors).

Fault diagnosis:

Alarm code: When the system malfunctions, the front panel of the drive will display an alarm code in the format of "A.xx". The manual provides a detailed list of the meanings, possible causes, and countermeasures for all alarm codes (such as A.10 overcurrent, A.30 regeneration error, A.51 overspeed, A.71/A.72 overload, A.81 encoder backup error, etc.).

No alarm display fault: If the motor does not rotate, vibrates abnormally, or has unstable speed but no alarm display, it is necessary to check the power supply, wiring, input signal status, parameter settings, etc. The manual provides a detailed troubleshooting table, indexed by symptoms, causes, and solutions.

Technical data summary

Project SGMBH servo motor SGDH servo driver

Rated output 22 kW -55 kW 22 kW -55 kW (matched with motor)

Rated speed 1500 min ⁻¹-

Maximum speed 2000 min ⁻¹-

Rated torque 140-350 N · m-

Main circuit of power supply voltage: three-phase 380-480VAC, ± 10% Main circuit: three-phase 380-480VAC, ± 10%

Control power supply -24 VDC ± 15%

Feedback method: 17 bit incremental/absolute encoder (optional 20 bit) supports incremental/absolute encoder

Control modes - speed/position/torque control and multiple composite modes

Environmental temperature 0~40 ° C 0~55 ° C

Protection level IP44 (fully enclosed, self cooling) base installation, IP20