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Working Principle of Polarization Power Supply
May 31, 2017

The circuits of this device can be divided into main circuit and control circuit.

1 Main circuit:

    As shown in the figure, the three-phase bridge rectifier circuit is used as the main circuit, the valve side of which is equipped with opening and closing surge absorber circuits and each arm is centrally provided with commutating overvoltage protection circuit. The three-phase AC voltage is reduced through a rectifier transformer and rectified by a thyristor before outputting the DC current 150A and voltage 150V.

2 Control circuit: (as shown in the figure)

    It is composed of the fault signal detection circuit and trigger circuit.

2.1 Fault signal detection circuit:

Current overload: in case of major loop circuit overload, the trigger pulse will be blocked until fault clearance.

2.2 Trigger circuit

1) Product outside view:


2) Basic technical parameters

l Nominal line voltage at the main circuit valve side: ≤600V(45∽55HZ)

l Controller working power supply: single-phase AC 220V±10%; current A≤0.0.12A or DC power supply DC24V/1A,DC5V/0.5A

l  Controller synchronizing signal: three-phase synchronous, AC24~380V, 45∽55HZ, current A≤5mA

l Voltage feedback signal: DC 0∽10V

l Current feedback signal: DC 0∽5V

l Analog quantity A/B spare channel: DC 0∽5V

l Analog potentiometer interface: self supplied power source, each interface can only connect a potentiometer with R≥10K.

l Digital potentiometer interface: switching value, self supplied power source, each interface can connect two passive buttons, one for increase and the other for decrease.

l 4-way switch input node: self supplied power source, not mixed with other power sources

l 4-way switch output node: passive relay output (normally open node) 24V/1A

l Pulse phase shift range: rectifier operation α=0~180°, inversion operation β=30~90°

l Pulse asymmetry degree of each phase: ≤0.3°

l Trigger pulse characteristics: voltage >6.5V, peak current >800mA

l Pulse signal width: 18° wide, double-narrow pulse train, interval 60°

l Number of output pulse ways: 12-way modulated trigger pulse isolated output

l Soft start/soft stop time: 0~120s adjustable

l Maximum boundary dimensions: 200㎜×180㎜×40㎜‘

3) Boundary dimensions and installation

Maximum boundary dimensions of XAZK-ST6M/12M digital trigger controller: 200mm (length) ×180mm (width) ×40mm (height)

Only four Ф4 bolts are required for installation, as shown in the outside and assembly drawing of XAZK-ST6M/12M intelligent digital controller.

l Boundary dimensions, as shown in Figure 1

l Terminal description:


Terminal Connection Diagram

4) Close-control digital panel:

l Embeddable in the cabinet surface, PCB material shell, 192*64 resolution, large screen, white light and black words, wide-temperature industrial LCD

l Directly take power from the controller without special power supply and directly connect the controller through the product connecting line

l Standard industrial handheld terminal keyboard with 17 keys, simpler and more humanized operation to set all parameters of the controller

l Boundary dimensions 160*90*40, solid snap joint. 

5) Option list of short-circuit terminal:


Short-circuit terminal

Functional description



Blocking pulse when grounded


Normal operation when disconnected


Controller reset when grounded


Normal operation when disconnected


Closed-loop working status when grounded

Open-loop working status when disconnected


Constant-voltage working status when grounded

Constant-current working status when disconnected


Digital given rise when grounded

No action when disconnected


Digital given drop when grounded

No action when disconnected


6) XAZK-ST6M/12M Digital trigger controller debugging

Digital panel: The digital trigger controller is directly equipped with a Chinese digital operation panel with a buzzer. When touch-button is pressed effectively, the buzzer issues the indication sound "DI". As shown below, each parameter name is attached with an indicator light. The corresponding indicator light is on when a parameter is set; the indicator light after overcurrent is on when the overcurrent value is set. LED digital tube window displays the current parameter value. Press [↑] and [↓] to increase or decrease the parameter value and then press [ENT] to save the modified data. Press [←] and [→] to select the parameter to be set.



Parameter page-up key


Parameter page-down key


Parameter value increase key


Parameter value decrease key



Enter key to save the modified data.

Note: A password set item on the panel can only display the feedback and set the set value when a wrong password is entered, and can set all parameters when the correct password is entered. The password is 0.

6.1) Connect dummy load: connect a section of electric stove wire to make the DC current at 10~20A when outputting the rated DC voltage. Set STM12 open loop working mode.

6.2) Preliminary pulse inspection: raise the given value and STM12 generates pulse after delivery of current to the controller. Check whether the pulse is to the element.

6.3) Choose the pulse clock count: the pulse clock count selection function of the handheld terminal can change the pulse clock count. Select the appropriate pulse clock count to make STM12 pulse adapt to the main circuit and achieve the given value from 0 to maximum and main circuit output voltage from 0 to maximum smoothly without out of control.

6.4) The user with pulse adaptive main circuit function can enable this function, so that STM12 pulse automatically adapts to the main circuit without manual setting. This function can only be used at small dummy load debugging.

6.5) Adjust the voltage feedback amplitude: guarantee the linear change of the feedback voltage with the main circuit voltage, 5V≤UF, amplitude ≤10V

6.6) Set the voltage rate: set the voltage rate to 1.00, then view the voltage feedback displayed value V and record the actual value V'' of the voltage. Voltage rate calculation formula: voltage rate = V'' (actual value) ÷V (voltage feedback displayed value), such as actual voltage value V'' = 17.0V, and current feedback displayed value V=340, and then the voltage rate = V'' (actual value) ÷V (voltage feedback displayed value) = 17. 0÷340=0.05, then set the voltage rate to 0.05.

6.7) Adjust the following parameters through the digital panel: ① overvoltage value, ② voltage limiting value, ③ minimum control angle α.

6.8) True load debugging: connect the true load to make the output current at about 10%~50% of the rated current and ensure normal current/voltage feedback collected by the digital controller.

6.9) Set the current rate: set the voltage rate to 1.00, then view the current feedback displayed value I and record the actual current I''. Current rate calculation formula: rate = I'' (actual value) ÷I (current feedback displayed value), such as actual current value I'' = 1200A, current feedback displayed value I=120 and current rate = I'' ÷I=1200÷120=10.0, then set the current rate to 10 times.

6.10) Through the digital panel manual, adjust: 1. Overcurrent value, 2. current limiting value, 3. soft start time, 4. soft stop time.

6.11) Select PID regulator: after manual setting of the basic parameters such as P and I, the system will start PID parameter self-tuning function and the controller automatically obtains the optimal parameter adapting to the load if the basic parameters cannot meet the system operation requirements. The basic parameters can be reset according to the self-tuned value of PI parameters.

7) Precautions

u Take down the digital controller when using the thyristor unit for insulation test; otherwise, the digital controller will be damaged permanently.

u Select the shielded twisted pairs as the communication line and trigger pulse line and note the wiring polarity without inverse connection.

u The company is not responsible for the damage to the components other than the digital controller during use. The machine shall not be removed and the warranty label and user parameter label shall not be damaged during warranty.

u To prevent closing impact of the main circuit, the control panel shall be powered on before the main circuit. The controller start end is closed during or after power-on of the main circuit.