Typical products of proportional amplifier
Typical products of proportional amplifier
1. Proportional amplifier for proportional pressure
The commonly used proportional amplifiers for proportional pressure valves are vt2000, vt2010 and vt2013. These proportional amplifiers have similar functions, but the difference is that the current situation in the initial section is different. They need to be selected according to the specific proportional pressure valve, and they are only applicable to proportional pressure valves with a proportional electromagnet impedance of 19.5 Ω. The proportional pressure valve with electromagnet impedance of 5.4 Ω needs to be controlled by vt-vspa1-1 proportional amplifier. At the same time, vt-vspa1-1 proportional amplifier can also realize vt2000, vt2010, vt2013 and other amplifier functions respectively through internal switch switching, which is used to control the proportional pressure valve with proportional electromagnet impedance of 19.5 Ω.
Figure 75 shows the structural block diagram of vt2000 proportional amplifier. It is mainly composed of differential amplifier ①, adder ②, internal command ③, ramp function generator ④, current regulator ⑤, output stage ⑥, pulse width modulation ⑦ and voltage divider ◎.
Vt-vspa1-1 proportional amplifier is more powerful than vt2000 in function. Its internal structure is different from vt2000, but its principle is similar. Figure 76 shows the structural block diagram of vt-vspa1-1, which is mainly composed of differential amplifier ①, adders ②, ⑤, ⑮, internal command ③, ramp generator ④, generators ⑥ and ⑦ of typical curves 1 and 2, current regulator ⑧, output stage ⑨, pulse width modulation ⑩, signal monitor ⑫, monitor ⑬ and power block ⑭. In Figure 76, ⑪ is proportional electromagnet.
2. Proportional amplifier for proportional direction
There are many forms of proportional directional valve, and the proportional amplifiers used are also different. Here we introduce the proportional amplifier used by the 4wrz pilot proportional directional valve without live feedback. The electromagnet impedance of 4wrz proportional directional valve can be divided into 19.5 Ω and 5.4 Ω. The proportional directional valves with these two impedances are controlled by vt3006 or vt3000 and vt-vspa250 respectively. In fact, the structure and function of these two amplifiers are similar, and the biggest difference is that the output current of the amplifier is different.
Figure 77 shows the structural block diagram of vt3006 proportional amplifier, which is mainly composed of command signal control device ①, differential amplifier ②, adders ③ and ⑥, ramp generator ④, step function generator ⑤, power amplification stage ⑦ and power supply ⑧.
Vt-vspa2-50 can be divided into T5 and T1, corresponding to vt3006 and vt3000 respectively. T5 can realize five slopes, while T1 can only realize one slope. Figure 78 shows the structural block diagram of vt-vspa250t5 proportional amplifier, which is mainly composed of command signal control device ①, differential amplifier ②, adders ③ and ⑥, ramp generator ④, step function generator ⑤, PI regulator, output stage ⑧, power supply ⑨, monitor ⑩, etc. Vt-vspa2-50 can be divided into T5 and T1, corresponding to vt3006 and vt3000 respectively. T5 can realize five slopes, while T1 can only realize one slope. Figure 78 shows the structural block diagram of vt-vspa250t5 proportional amplifier, which is mainly composed of command signal control device ①, differential amplifier ②, adders ③ and ⑥, ramp generator ④, step function generator ⑤, PI regulator, output stage ⑧, power supply ⑨, monitor ⑩, etc.
3. Rexrothvt-vrpd-1 digital two-way proportional amplifier with displacement electrical feedback 3 Rexrothvt-vrpd-1 digital dual channel proportional amplifier with displacement electrical feedback
The core part of the amplifier is a high-performance microcontroller, which realizes all the functions of the signal processing circuit in the analog proportional amplifier through the program, while the function of the closed-loop regulation of the current of the proportional electromagnet is still realized by the analog circuit. Figure 79 is its functional block diagram. The core part of the amplifier is a high-performance microcontroller, which realizes all the functions of the signal processing circuit in the analog proportional amplifier through the program, while the function of the closed-loop regulation of the current of the proportional electromagnet is still realized by the analog circuit. Figure 79 is its functional block diagram.
The basic characteristics of the proportional amplifier are: ① it is suitable for controlling the proportional valve with position electric feedback; ② Configure and set parameters of the amplifier through 485 serial interface; ③ A powerful micro controller is used to realize the task of signal processing; ④ The parameters of various applicable types of valves are preset in the program, and the model of the controlled valve is selected through the serial port interface; ⑤ The input of the set value can select the voltage or current according to the actual needs, and the voltage input is differential input; ⑥ Set value input can adjust gain and offset; ⑦ The internal power supply is switching power supply; ⑧ The input signal of four binary codes is used to start the parameter setting (set value) from the memory, which can store up to 16 sets of parameters. The basic characteristics of the proportional amplifier are: ① it is suitable for controlling the proportional valve with position electric feedback; ② Configure and set parameters of the amplifier through 485 serial interface; ③ A powerful micro controller is used to realize the task of signal processing; ④ The parameters of various applicable types of valves are preset in the program, and the model of the controlled valve is selected through the serial port interface; ⑤ The input of the set value can select the voltage or current according to the actual needs, and the voltage input is differential input; ⑥ Set value input can adjust gain and offset; ⑦ The internal power supply is switching power supply; ⑧ The input signal of four binary codes is used to start the parameter setting (set value) from the memory, which can store up to 16 sets of parameters.
