Power generating arrangement employing synchronous dynamoelectric machine having improved dynamic and transient stability

Claim 2

A power generating arrangement having an improved dynamic and transient stability characteristic comprising: a dynamoelectric machine; an excitation source to provide excitation for the field winding of said dynamoelectric machine, the terminal voltage of said dynamoelectric machine varying with the field voltage of the field winding in a manner that may be approximately represented by a constant, a real root function and a complex root function; compensating means for controlling said excitation source, saiD compensating means producing an effect on the relationship between the field voltage and the terminal voltage that approximates the inverse of said complex root function over a desired operating range and comprising means for developing an input reference signal; a first summing node having the input reference signal and also an output signal representing the terminal voltage applied thereto to produce a signal based upon a comparison thereof; a first integrator circuit connected to the output of said first summing node; a second summing node having means for modifying the input reference signal by a first constant; the first modified reference signal and the output of said first integrator circuit applied thereto; a second integrator circuit having the output of said second summing node applied thereto; means for modifying the input reference signal by a second constant; a third summing node having the outbut of said second integrator circuit and the second modified input reference signal applied thereto; means for modifying the output of said third summing node by a third constant and supplying the modified output of said third summing node back to said second summing node; and means for modifying the output of said third summing node by a third constant and supplying the modified output of said third summing node back to said second summing node; and means for modifying the output of said third summing node by a fourth constant to provide the output signal.

Claim 3

A power generating arrangement as claimed in claim 1 wherein: said excitation source for the field winding is a rotary exciter; and said compensating means controls the output of said rotary exciter.

Claim 4

A power generating arrangement as claimed in claim 1 and further comprising supplementary feedback means to supply a supplementary signal indicative of a machine parameter to said first summing node.

Claim 5

A power generating arrangement as claimed in claim 1 wherein said first and second integrator circuits comprise time delay circuits.

Claim 6

A power generating arrangement as claimed in claim 1 wherein said first second, third and fourth constants may be adjusted to provide the desired modification of the compensating network for the purpose of controlling field winding excitation.

Claim 7

A power generating arrangement having an improved dynamic and transient stability characteristic comprising: a synchronous dynamoelectric machine; a rotary exciter to provide excitation for the field winding of said dynamoelectric machine, the terminal voltage of said dynamoelectric machine varying with the field voltage of the field winding in a manner that may be approximately represented by a constant, a real root function and a complex root function; a voltage regulator to regulate the excitation voltage produced by said rotary exciter; a reference source to provide a reference signal indicative of a desired excitation to be applied to the field winding; feedback means to provide a feedback signal indicative of the terminal voltage of said dynamoelectric machine; a first summing node to produce a control signal for said rotary exciter based upon a comparison of said reference signal and said feedback signal; and compensating means for controlling said rotary exciter to cause the excitation of the field winding to be modified to minimize the effects of said complex root function on the relationship between the field voltage and terminal voltage, said compensation means being a compensating network having means for an input signal and an output signal and comprising: a second summing node having the input signal and the output signal applied thereto to produce a signal based upon a comparison thereof; a first integrator circuit connected to the output of said second summing node; a third summing node having the input signal altered by a first constant altering means and the output of said first integraTor circuit applied thereto; a second integrator circuit having the output of said third summing node applied thereto; and a fourth summing node having the output of said second integrator circuit and the input signal altered by a second constant altering means applied thereto, the output of said fourth summing node being altered by a thrid constant altering means and connected back to said third summing node and being altered by a fourth constant altering means to provide the output signal to said exciter.

Claim 8

A power generating arrangement having an improved dynamic and transient stability characteristic comprising: a synchronous dynamoelectric machine; a rotary exciter to provide excitation for the field winding of said dynamoelectric machine, the terminal voltage of said dynamoelectric machine varying with the field voltage of the field winding in a manner that may be approximately represented by a constant, a real root function and a complex root function; a voltage regulator to regulate the excitation voltage produced by said rotary exciter; a reference source to provide a reference signal indicative of a desired excitation to be applied to the field winding; feedback means to provide a feedback signal indicative of the terminal voltage of said dynamoelectric machine; a first summing node to produce a control signal for said rotary exciter based upon a comparison of said reference signal and said feedback signal; and compensating means for controlling said rotary exciter to cause the excitation of the field winding to be modified to minimize the effects of said complex root function on the relationship between the field voltage and terminal voltage, said compensation means being a compensating network having means for an input signal and an output signal and comprising: a second summing node having the input signal and the output signal applied thereto to produce a signal based upon a comparison thereof; a first integrator circuit connected to the output of said second summing node; a third summing node having the input signal altered by a first constant altering means and the output of said first integraTor circuit applied thereto; a second integrator circuit having the output of said third summing node applied thereto; and a fourth summing node having the output of said second integrator circuit and the input signal altered by a second constant altering means applied thereto, the output of said fourth summing node being altered by a thrid constant altering means and connected back to said third summing node and being altered by a fourth constant altering means to provide the output signal to said exciter.

Claim 9

A power generating arrangement as claimed in claim 6 and further comprising supplementary feedback means to supply a supplementary signal indicative of a machine parameter.

Claim 10

A control system for improving the dynamic and transient stability characteristic of a dynamoelectric machine comprising: an excitation source to provide excitation for the field winding of the dynamoelectric machine, the terminal voltage of the dynamoelectric machine varying with the field voltage of the field winding in a manner that may be approximately represented by a constant, a real root function and a complex root function; compensating means for controlling said excitation source to cause the excitation of the field winding to be modified by minimizing the effects of said complex root function on the relationship between the field voltage and the terminal voltage; a reference source to provide a reference signal indicative of a desired excitation to be applied to the field winding; feedback means to provide a feedback signal indicative of the terminal voltage of the dynamoelectric machine; supplementary feedback means to supply a supplementary signal indicative of a parameter of the dynamoelectric machine; a first summing node to produce a control signal for said excitation source based upon a comparison of said reference signal, said feedback signal and said supplementary signal; a second summing node having applied thereto said control signal and the output of said excitation source after passage through a damping module; a voltage regulator to convey the output of said second summing node to said excitation source and to regulate the excitation applied to the field winding; and said compensating means is a compensating network having an input signal and an output signal and comprises: a third summing node having the input signal and the output signal applied thereto to produce a signal based upon a comparison thereof; a first integrator circuit connected to the output of said third summing node; a fourth summing node having the input signal altered by a first constant and the output of said first integrator circuit applied thereto; a second integrator circuit having the output of said fourth summing node applied thereto; and a fifth summing node having the output of said second integrator circuit and the input signal altered by a second constant applied thereto, the output of said fifth summing node being altered by a third constant and connected back to said fourth summing node and being altered by a fourth constant to provide the output signal.

Claim 11

A control system for improving the dynamic and transient stability characteristic of a dynamoelectric machine comprising: an excitation source to provide excitation for the field winding of the dynamoelectric machine, the terminal voltage of the dynamoelectric machine varying with the field voltage of the field winding in a manner that may be approximately represented by a constant, a real root function and a complex root function; compensating means for controlling said excitation source to cause the excitation of the field winding to be modified by minimizing the effects of said complex root function on the relationship between the field voltage and the terminal voltage; a reference source to provide a reference signal indicative of a desired excitation to be applied to the field winding; feedback means to provide a feedback signal indicative of the terminal voltage of the dynamoelectric machine; supplementary feedback means to supply a supplementary signal indicative of a parameter of the dynamoelectric machine; a first summing node to produce a control signal for said excitation source based upon a comparison of said reference signal, said feedback signal and said supplementary signal; a second summing node having applied thereto said control signal and the output of said excitation source after passage through a damping module; a voltage regulator to convey the output of said second summing node to said excitation source and to regulate the excitation applied to the field winding; and said compensating means is a compensating network having an input signal and an output signal and comprises: a third summing node having the input signal and the output signal applied thereto to produce a signal based upon a comparison thereof; a first integrator circuit connected to the output of said third summing node; a fourth summing node having the input signal altered by a first constant and the output of said first integrator circuit applied thereto; a second integrator circuit having the output of said fourth summing node applied thereto; and a fifth summing node having the output of said second integrator circuit and the input signal altered by a second constant applied thereto, the output of said fifth summing node being altered by a third constant and connected back to said fourth summing node and being altered by a fourth constant to provide the output signal.

Claim 12

A control system as claimed in claim 8 wherein means for adjusting said first, second, third and fourth constants are provided for the desired modification of the field winding excitation.