Background technology
Switch mode power supply apparatus (the SwitchedModePowerSupply be widely used as DC stabilization power supply, SMPS) utilize the switch process device of semiconductor element and control flow of power, therefore, compared with stabilized power supply in the past, be a kind of stabilized power supply with high efficiency, small-sized and light-weighted advantage.
But, along with supply unit becomes maximization, being restricted when improving the switching frequency of large electrical power switching element, being therefore difficult to realize miniaturized and lightweight.
In order to solve the problem a little, import and Large Copacity has been divided into low capacity module, having embodied the mode of jumbo supply unit by being run by the modular concurrent of low capacity.
But, in the existing supply unit run by the modular concurrent of low capacity, if a module breaks down, then can not control electric current, thus the module of remaining normal condition also cannot drive.
Summary of the invention
The present invention researches and develops to solve the problem a little, the object of the present invention is to provide a kind of such switch mode power supply apparatus: embodying in the supply unit of large capacity power device by the running of the modular concurrent of low capacity, even if at least one module in described low capacity module breaks down, also can be continued to load supply power by the residue module except the module broken down.
In order to achieve the above object, supply unit according to the present invention is parallel-connected on master controller by multiple power supply supplying module, each power supply supplying module parallel running and to the supply unit of load supply power, this power supply supplying module comprises blocks current control part, and the blocks current output valve of the output of this power supply supplying module and the secondary voltage that produces from described master controller Vcont input voltage are applied to PWM controller by this blocks current control part.
Described blocks current control part comprises blocks current control circuit, this blocks current control circuit comprises: input, this input possesses (+) input terminal and (-) input terminal, from the detection current splitter of the output of described power supply supplying module by channel amplifier to this (+) input terminal input module current output value, the Vcont voltage transmitted by control line from described master controller inputs to this (-) input terminal; And output, the secondary voltage that its output is inputted by described input is also applied to described PWM controller.
Further, described blocks current control part regulates the OFFSET of described channel amplifier (being biased) and I/MAX (maximum current) amount, makes the current deviation of each power supply supplying module be zero.
As mentioned above, according to supply unit of the present invention, even if at least one module in described low capacity module breaks down, also can be continued to load supply power by the residue module except the module broken down.
Further, the control object due to blocks current control circuit is electric current, therefore composition module Current Control, thus improves the overload characteristic of transducer.
Embodiment
Below, specific embodiments of the invention are described in detail with reference to accompanying drawing.
Fig. 1 is the block diagram of the switch mode power supply apparatus diagrammatically shown according to a preferred embodiment of the invention.
With reference to Fig. 1, supply unit according to the present invention comprises the master controller 20 being connected in parallel by the power supply supplying module 10 of the module composition being divided into multiple low capacity and described each power supply supplying module and control line and being controlled described each power supply supplying module.
At this, in described power supply supplying module 10, described master controller 20 is connected in parallel with control line, therefore in theory, a master controller can connect numerous (N+1).
Such as, when the capacity of supply unit is 100kW, is connected in parallel the power supply supplying module of 5 20kW and runs, thus the capacity process of 100kW can be carried out.
Described power supply supplying module 10 comprises: input rectifying portion 110, and it carries out rectification to input voltage; Output translator 120, the voltage transitions after described rectification is the voltage being supplied to load by it, and the stable electric current supply in control module.
It is the effect of DC voltage that described input rectifying portion 110 plays input AC voltage commutation, and described output translator 120 plays the effect DC voltage of rectification being converted to the voltage being supplied to load.
Described output translator 120 comprises: PWM controller (inverter) 121, and it is control impuls width in order to the stabilisation of output voltage; Blocks current control part 123, the stable Current Control in its control module; Rectifier 122, it carries out rectification to the voltage of described stabilisation.
Described output translator 120 is by by described PWM controller 121, stabilized voltage outputs to load through described rectifier 122.
At this, described blocks current control part 123 applies to be adjusted to make the current deviation of each power supply supplying module be the voltage of zero to described PWM controller 121, and described PWM controller 121 forms drive pulse waveform and finally adjusts output voltage and electric current.
Described master controller 20 comprises microcontroller for controlling supply unit total system and voltage control circuit and current control circuit.
Fig. 2 is the circuit diagram of the master controller diagrammatically shown according to a preferred embodiment of the invention.
Voltage, electric current runtime value, while the various alarm of process, are supplied to control circuit by described microcontroller.
Described voltage control circuit compares the output voltage detected and voltage runtime value and produces error voltage, described current control circuit adds up to amplifier by electric current, current value from each power supply supplying module is all added up to, the current value added up to becomes whole electric currents of system, and compares with Current Control value and produce error voltage.
The signal produced by described voltage control circuit and current control circuit by forming Vcont while diode D1, D2, and as each module control signal and send.
At this, described Vcont is subject to the restriction of the voltage level limiter of VcLimiter, and this confined value determines the maximum current of each module.
Fig. 3 is the circuit diagram of blocks current control part according to a preferred embodiment of the invention.
With reference to Fig. 3, module output current value through channel amplifier in the current detecting splitter of output is applied to (+) input terminal of the input of blocks current control circuit by described blocks current control part 123, meanwhile module output current value is sent in master controller by control line through resistance (R-CURR).
Further, the Vcont voltage carrying out autonomous controller 20 is applied to (-) input terminal of the input of blocks current control part and becomes the output of circuit by buffer.
At this, the secondary voltage exported by the output of described blocks current control circuit is imported into PWM controller 121 and forms the drive pulse waveform of output translator, final adjustment output voltage and electric current.
Each voltage supplying module 10 according to the present invention receives all identical Vcont from master controller, and the electric current flow through in each power supply supplying module 10 and described Vcont voltage matches, as long as accurately regulate OFFSET and the I/MAX amount of channel amplifier, then the current deviation of each power supply supplying module 10 is zero.Therefore, it is possible to stably control electric current, even if the part in power supply supplying module breaks down, also can be come to load supply power by remaining power supply supplying module.
Further, the control object due to blocks current control circuit is electric current, therefore composition module Current Control, thus improves the overload characteristic of transducer.
Above, be illustrated according to a preferred embodiment of the invention, but protection scope of the present invention is not limited to above-described embodiment, those skilled in the art can carry out various correction and change in the scope not departing from thought of the present invention and technical field.