The PCB circuit of the generator set automatic voltage regulator has the characteristics of good voltage regulation performance, strong adaptability and low cost. It can be used for automatic voltage regulation of various medium and small internal combustion generator sets and hydropower stations, and can also be used to retrofit old generator sets.
The working principle of the PCB circuit: The automatic voltage regulator PCB circuit of this generator set consists of a synchronous trigger power supply PCB circuit, a relaxation oscillation trigger, a voltage regulation control PCB circuit, a reactive current regulation PCB circuit, and an external power insufficient protection PCB circuit.
The synchronous trigger power supply PCB circuit consists of a power transformer T, rectifier diodes VD4~VD9, Zener diode VS1, and resistor R1.
The relaxation oscillation trigger PCB circuit consists of transistor V2, unijunction transistor VU, resistors R2~R5, and capacitors C2 and C3.
The voltage regulation control PCB circuit consists of a power transformer T, rectifier diodes VD10~VD15, resistors R6~R8, potentiometer RP2, capacitor C1, and Zener diodes VS2 and VS3.
The reactive current regulation PCB circuit consists of a current transformer TA, a potentiometer RP1, a switch S1, and rectifier diodes VD16~VD19.
The excitation PCB circuit consists of the equal excitation winding WE of the AC generator G; diodes VD1 and VD2; thyristor VT; normally closed contacts K1~1 of K1; fuse FU1, etc.
The PCB circuit for protection against insufficient external power consists of resistors R9~Rl2, diodes VD25~VD31, transistor V1, capacitors C4~C8, and relay K2.
The magnetization PCB circuit consists of magnetization button S2, diodes VD2O~VD24, normally closed contacts K1~2 of K1, fuse FU2, and winding W4 of T.
The three-phase AC voltage from generator G is stepped down by transformer T, generating a 30V three-phase sinusoidal AC voltage on windings W5-W7 and an 18V three-phase sinusoidal AC voltage on windings W8-W10. The voltage on windings W5-W7 is rectified by transformers VD4-VD9, current-limited by resistor R1, and regulated by transformer VS1 to generate a 15V trapezoidal DC voltage, which serves as the synchronous power supply for the relaxation oscillation trigger. The voltage on windings W8-W10 is rectified by transformers VD10-VD15, current-limited by resistors R6 and RP2, and filtered by transformer C1. This voltage is then applied to the relaxation oscillation trigger via a bridge measurement PCB circuit composed of resistors R7, R8, and transformers VS2 and VS3, serving as its control signal voltage.
When generator G first starts generating electricity, the voltage across C (the input voltage of the bridge measurement PCB circuit) is low, VS2 and VS3 are not conducting, and the relaxation oscillator trigger does not operate. When the terminal voltage of generator G rises to 200V, VS2 and VS3 break down and conduct, causing the relaxation oscillator trigger to operate. A pulse wave signal is output from the first base of VU, and this signal is applied to the gate of VT via VD3 as its trigger signal. In this way, the generator establishes no-load voltage in a short time.
The PCB circuit of the automatic voltage regulator for generator sets introduced in this example has the characteristics of good voltage regulation performance, strong adaptability and low cost. It can be used for automatic voltage regulation of various medium and small internal combustion generator sets and hydropower stations, and can also be used to retrofit old generator sets.
The working principle of the PCB circuit: The automatic voltage regulator PCB circuit of this generator set consists of a synchronous trigger power supply PCB circuit, a relaxation oscillation trigger, a voltage regulation control PCB circuit, a reactive current regulation PCB circuit, and an external power insufficient protection PCB circuit.
The synchronous trigger power supply PCB circuit consists of a power transformer T, rectifier diodes VD4~VD9, Zener diode VS1, and resistor R1.
The relaxation oscillation trigger PCB circuit consists of transistor V2, unijunction transistor VU, resistors R2~R5, and capacitors C2 and C3.
The voltage regulation control PCB circuit consists of a power transformer T, rectifier diodes VD10~VD15, resistors R6~R8, potentiometer RP2, capacitor C1, and Zener diodes VS2 and VS3.
The reactive current regulation PCB circuit consists of a current transformer TA, a potentiometer RP1, a switch S1, and rectifier diodes VD16~VD19.
The excitation PCB circuit consists of the equal excitation winding WE of the AC generator G; diodes VD1 and VD2; thyristor VT; normally closed contacts K1~1 of K1; fuse FU1, etc.
The PCB circuit for protection against insufficient external power consists of resistors R9~Rl2, diodes VD25~VD31, transistor V1, capacitors C4~C8, and relay K2.
The magnetization PCB circuit consists of magnetization button S2, diodes VD2O~VD24, normally closed contacts K1~2 of K1, fuse FU2, and winding W4 of T.
The three-phase AC voltage from generator G is stepped down by transformer T, generating a 30V three-phase sinusoidal AC voltage on windings W5-W7 and an 18V three-phase sinusoidal AC voltage on windings W8-W10. The voltage on windings W5-W7 is rectified by transformers VD4-VD9, current-limited by resistor R1, and regulated by transformer VS1 to generate a 15V trapezoidal DC voltage, which serves as the synchronous power supply for the relaxation oscillation trigger. The voltage on windings W8-W10 is rectified by transformers VD10-VD15, current-limited by resistors R6 and RP2, and filtered by transformer C1. This voltage is then applied to the relaxation oscillation trigger via a bridge measurement PCB circuit composed of resistors R7, R8, and transformers VS2 and VS3, serving as its control signal voltage.
When generator G first starts generating electricity, the voltage across C (the input voltage of the bridge measurement PCB circuit) is low, VS2 and VS3 are not conducting, and the relaxation oscillator trigger does not operate. When the terminal voltage of generator G rises to 200V, VS2 and VS3 break down and conduct, causing the relaxation oscillator trigger to operate. A pulse wave signal is output from the first base of VU, and this signal is applied to the gate of VT via VD3 as its trigger signal. In this way, the generator establishes no-load voltage in a short time.
