Semiconductor integrated circuit, pwm signal output device, and power conversion control apparatus

Abstract

Provided is a control technique of a PWM conversion type power converter capable of compensating for a voltage error due to voltage drop mainly at a switching element and managing a switching time of a PWM signal at the same time, and capable of suppressing increase/decrease of software operation load and addition of a hardware circuit to the minimum. A semiconductor integrated circuit having a PWM signal generating unit which generates a PWM signal is provided with a PWM timer unit including a counter counting a pulse width of a pulse signal inputted from the outside with delay from a PWM signal, a register loading a counter value of the counter in synchronization with the PWM signal, and an A/D converting unit converting an analog signal serving as a source signal of the pulse signal inputted from the outside to a digital signal.

1 - 14 . (canceled) 
     
     
         15 . A semiconductor integrated circuit comprising:
 a PWM signal generator that generates a PWM signal;   a register that loads a value of a pulse width of a pulse signal inputted from an outside of the semiconductor integrated circuit with delay from the PWM signal in synchronization with the PWM signal; and   an A/D converter that converts an analog signal serving as a source signal of a pulse signal inputted from outside of the semiconductor integrated circuit to a digital signal.   
     
     
         16 . The semiconductor integrated circuit according to  claim 15 ,
 wherein the register and the A/D converter configure at least one of the register and the A/D converter.   
     
     
         17 . The semiconductor integrated circuit according to  claim 15 ,
 wherein the pulse width is counted using a level selector that selects a level of a pulse signal to be counted.   
     
     
         18 . The semiconductor integrated circuit according to  claim 15 ,
 wherein the A/D converter amplifies an inputted analog signal in the A/D converter and comprises an amplification gain selector.   
     
     
         19 . The semiconductor integrated circuit according to  claim 18 ,
 wherein the amplification gain selector sets an amplification gain to even multiple or 1/even-number multiple.   
     
     
         20 . The semiconductor integrated circuit according to  claim 15 ,
 wherein the register loads a value of the pulse width in synchronization with a carrier signal of the PWM signal generator, and   wherein the A/D converter starts A/D conversion in synchronization with a PWM signal of the PWM signal generator.   
     
     
         21 . A PWM signal output device comprising:
 a PWM signal generator that generates a PWM signal according to set time data;   a register that loads a value of a pulse width of a pulse signal inputted from an outside of the device with delay from the PWM signal in synchronization with the PWM signal;   an A/D converter that converts an analog signal serving as a source signal of a pulse signal inputted from outside of the device to a digital signal; and   a storage system that stores therein a PWM voltage command time value obtained by converting a voltage command value to time data, a PWM setting time value set in the PWM signal generator, a register value of the register, and an A/D conversion result value of the A/D converter,   wherein, in a cyclic processing performed for each predetermined cycle, a next PWM setting time value is calculated and set using the register value, the A/D conversion result value, the PWM voltage command time value, and the PWM setting time value.   
     
     
         22 . The PWM signal output device according to  claim 21 ,
 wherein an error voltage between the A/D conversion result value and the reference DC voltage value is obtained and a voltage command value is obtained by compensating for the error voltage, and   wherein an error time between a pulse width time of the pulse signal obtained from the register value and the PWM setting time value is obtained and the next PWM setting time value is calculated and set from the error time and the PWM voltage command time value.   
     
     
         23 . The PWM signal output device according to  claim 21 ,
 wherein an error voltage between the A/D conversion result value and the reference DC voltage value is obtained and a voltage command value is obtained by compensating for the error voltage, and   wherein an error time between a pulse width time of the pulse signal obtained from the register value and the PWM voltage command time value is obtained so that the next PWM setting time value is calculated and set from the error time and the PWM setting time value.   
     
     
         24 . The PWM signal output device according to  claim 21 ,
 wherein the A/D converter starts A/D conversion at a timing where a level of a PWM signal of the PWM signal generator is changed, and   wherein an error voltage is obtained from differences of respective A/D conversion result values and the voltage command value.   
     
     
         25 . The PWM signal output device according to  claim 21 ,
 wherein the A/D converter performs A/D conversion continuously to obtain an error voltage from an average value of the A/D conversion result values while the pulse signals are in the same level and the voltage command value.   
     
     
         26 . The PWM signal output device according to  claim 21 ,
 wherein the A/D converter performs A/D conversion continuously to obtain a minimal area based on a product A/D conversion result values and an A/D conversion time for each A/D conversion result and calculates the PWM voltage command time value from the minimal area.   
     
     
         27 . A power conversion control device comprising:
 a semiconductor integrated circuit; and   a power converting circuit having at least two switching elements that convert DC power to AC power,   wherein the semiconductor integrated circuit comprises
 a PWM signal generator that generates a PWM signal; 
 a register that loads a value of a pulse width of a pulse signal inputted from an outside of the semiconductor integrated circuit with delay from the PWM signal in synchronization with the PWM signal; 
 an A/D converter that converts an analog signal serving as a source signal of a pulse signal inputted from outside of the semiconductor integrated circuit to a digital signal; and 
 a storage system that outputs a signal of a predetermined pattern as the PWM signal, obtains an error time between a pulse width time of the pulse signal at the outputting time and a PWM setting time value or a PWM voltage command time value, and stores the error time as a delay time value of the at least two switching elements. 
   
     
     
         28 . The power conversion control device according to  claim 27 ,
 wherein abnormality of the switching element is determined from the delay time value stored in the storage system.