Since the 1970s till now, the number of industrial robots in our country has been quite large, and reached the world advanced level in some robot technologies. However, industrial robotics in developed countries in the West still lead China many years . The reason is not difficult to find: China's study of industrial robots to take the approach is mainly the first introduction of foreign advanced technology, and then its secondary development, which resulted in our own relatively few innovative technologies, has seriously hampered China's industrial robotics industry Development. In order to break the technological monopoly of foreign industrial robots in China, we must rely on our own efforts to master the key technologies of high-performance industrial robots and make innovations on the basis of the original ones. Since the actuator of the industrial robot joint is a motor, it is very important to obtain good control of the motor. In order to obtain excellent motor control performance, a high-performance AC servo drive system is required. Therefore, a high-performance AC servo drive system Is one of the key technologies of industrial robots. AC servo drive system hardware is the basis of software design, so the main task of this paper is based on the characteristics of industrial robot servo drive system, the system's hardware design. 1, hardware design 1.1DSP selection DSP system hardware design, including the choice of control chip, the main circuit drive and protection, peripherals, logic circuits, which is the basis of the entire control system design, DSP chip is the top priority. TMS320C5000 Series DSP features the lowest power consumption is designed specifically for consumer digital market, the lowest power consumption of only 0.33mA / MHz, so more used in everyday consumer products such as cameras, cell phones and so on. TI's TMS320C6000 family has the highest processing power and is a digital processor suitable for programming in high-level languages ​​such as C ++ / C, primarily for use in advanced areas such as military defense. Compared with C5000 and C6000 series DSP, TMS320C2000 series DSP because of its speed, high precision, high integration and other advantages, is currently the highest performance control processor. Among them, C28 series DSP is a new member of TMS320C2000 platform, which is improved by C24 series DSP. It is a chip that supports C / C ++ language design. C28 series DSP is very suitable for industrial control and unique in algorithm control Advantages, is a rare microprocessor, its efficiency can make it replace any other processor. C2000 series DSP does not contain Flash memory, ROM only; only F2000 series DSP contains ROM ROM, but also includes Flash memory, you can repeatedly erase, suitable for use in the initial stage of product development. If the TMS320C281x, you need to deliver the code to the manufacturer, the program is solidified to the TMS320C281x ROM, an increase of costs, so choose to use TMS320F281xDSP chip. Among them, TMS320F2812 TI company as the most important chip, with a high cost. In summary, the final choice of DSP model TMS320F2812. 1.2 position detection circuit design In this paper, the encoder used in the AC servo motor is a 17-bit absolute encoder manufactured by Tamagawa Co., Ltd., model TS5668N21. The general practice is to use the dedicated chip provided by the manufacturer for data processing. However, this method has a disadvantage that the dedicated The cost of the chip is very expensive, contrary to the purpose of developing an economical industrial robot in this paper. In order to reduce the cost, this paper designs a serial signal circuit that converts the absolute encoder signal into DSP. Inductance and optocoupler filter and surge can play a function, the absolute encoder output is a differential signal, so the need to chip SN65176BD (BDR) G4 absolute encoder differential signal can be converted to DSP Recognition of the serial signal, that is, TTL signal, in addition to the chip supply voltage DC 5V, so the drive system should also provide 5V DC power supply, because the industrial robot servo drive system uses a DSP to control two permanent magnet synchronous The idea of ​​the motor, the advantage is to reduce costs, give full play to the TMS320F2812 computing speed and rich peripheral resources, so the two motor encoder signals through the serial port SCIA and SCIB input to the same DSPTMS320F2812. 1.3 low-speed external input signal conversion circuit design Since external input signals such as parameter setting buttons need to be collected into the DSP, only the TTL level of 3.3V can be recognized by the DSPTMS320F2812, so a signal conversion circuit is needed. The circuit uses a bidirectional optocoupler, Very good play the role of isolation and protection, once the voltage is too large and other accidents, only need to replace the optocoupler to prevent the DSP interface has also been burned. Bidirectional optocoupler used in the circuit model for the Toshiba TLP280-4 / SOP-16, which SOP-16 in its package, the bi-directional optocoupler common either can be connected to 24V can also be connected to 0V, the use of very Convenient, through the circuit will be able to convert low-speed signals into TTL 3.3V signal to complete the signal conversion, in which the circuit capacitor from the filter effect. After the conversion of the TTL signal and the output between the need for an isolation circuit, the circuit mainly from the role of isolation protection, the circuit uses a one-way optocouplers, the model for the Toshiba TLP181 / SOP-4, in which SOP-4 for its package. 1.4 intelligent power module and isolated drive circuit design Intelligent Power Module IPM module for short, is an inverter DC to AC inverter is the key components of the system [3], the system uses MITSUBISHISEMICONDUCTOR company's fourth-generation IPM module, model PS21767, the module's The maximum output voltage of 600V, the maximum output current of 20A, the output range, the module also has a short circuit protection and undervoltage protection, when detected undervoltage or short circuit, the module stops working at the same time, but also through the FO pin Fault signal to the DSP, DSP immediately stop sending PWM signal, to achieve self-protection. IPM module uses POWEREX company's PS21767 module, its peripheral interface circuits include power supply circuit, fault signal output circuit. IPM input signal voltage of 15V, and PWM signal output voltage of 5V, in order to isolate the different voltage signals to suppress interference, the system makes the TMS320F2812 The PWM signal is first passed through the photocoupler and then into the IPM module. The optocoupler model is ACPL-P480. The chip has the advantages of short propagation delay and high common-mode rejection (CMR) capability, and is suitable for IPM interface isolation. IPM module