The invention relates to a three-phase
harmonic wave source, which comprises a
single chip microcomputer and a double-port parallel-port RAM (
Random Access Memory), and further comprises a hardware
clock, a phase-locked loop module, a 16-bit parallel-port CPLD (
Complex Programmable Logic Device) counting and scanning module, a first 8-bit parallel-port D / A (Digital-to-Analog) converter, a second 8-bit parallel-port D / A converter, a third 8-bit parallel-port D / A converter and a fourth 8-bit parallel-port D / A converter, wherein the
single chip microcomputer is used for writing in waveform data;the double-port parallel-port RAM is connected with the
single chip microcomputer; the hardware
clock is used for frequency control; the 16-bit parallel-port CPLD counting and scanning module is usedfor scanning the double-port parallel-port RAM in real time; both the first 8-bit parallel-port D / A converter and the second 8-bit parallel-port D / A converter are used for formulating an amplitude value and connected with the high-speed single
chip microcomputer; and both the third 8-bit parallel-port D / A converter and the fourth 8-bit parallel-port D / A converter are used for controlling output waveforms and connected with the double-port parallel-port RAM. The output ports of the first 8-bit parallel-port D / A converter and the second 8-bit parallel-port D / A converter are connected with a first
operational amplifier array; the output end of the first
operational amplifier array is connected with REF (Reference) ports of the third 8-bit parallel-port D / A converter and the fourth 8-bit parallel-port D / A converter; the output ends of the third 8-bit parallel-port D / A converter and the fourth 8-bit parallel-port D / A converter are connected with a second
operational amplifier array; and the second operational
amplifier array is provided with a
harmonic wave output end. The three-phase
harmonic wave source provided by the invention has the advantages of high reliability, lower hardware cost and higher working efficiency.